2006-11-18 02:00:24

by Karsten Wiese

[permalink] [raw]
Subject: [PATCH] Regard MSRs in lapic_suspend()/lapic_resume()


Read/Write APIC_LVTPC and APIC_LVTTHMR only,
if get_maxlvt() returns certain values.
This is done like everywhere else in i386/kernel/apic.c,
so I guess its correct.
Suspends/Resumes to disk fine and eleminates an smp_error_interrupt()
here on a K8.

Signed-off-by: Karsten Wiese <[email protected]>
---
arch/i386/kernel/apic.c | 22 ++++++++++++++++++----
1 files changed, 18 insertions(+), 4 deletions(-)

diff --git a/arch/i386/kernel/apic.c b/arch/i386/kernel/apic.c
index 2fd4b7d..776d9be 100644
--- a/arch/i386/kernel/apic.c
+++ b/arch/i386/kernel/apic.c
@@ -647,23 +647,30 @@ static struct {
static int lapic_suspend(struct sys_device *dev, pm_message_t state)
{
unsigned long flags;
+ int maxlvt;

if (!apic_pm_state.active)
return 0;

+ maxlvt = get_maxlvt();
+
apic_pm_state.apic_id = apic_read(APIC_ID);
apic_pm_state.apic_taskpri = apic_read(APIC_TASKPRI);
apic_pm_state.apic_ldr = apic_read(APIC_LDR);
apic_pm_state.apic_dfr = apic_read(APIC_DFR);
apic_pm_state.apic_spiv = apic_read(APIC_SPIV);
apic_pm_state.apic_lvtt = apic_read(APIC_LVTT);
- apic_pm_state.apic_lvtpc = apic_read(APIC_LVTPC);
+ if (maxlvt >= 4)
+ apic_pm_state.apic_lvtpc = apic_read(APIC_LVTPC);
apic_pm_state.apic_lvt0 = apic_read(APIC_LVT0);
apic_pm_state.apic_lvt1 = apic_read(APIC_LVT1);
apic_pm_state.apic_lvterr = apic_read(APIC_LVTERR);
apic_pm_state.apic_tmict = apic_read(APIC_TMICT);
apic_pm_state.apic_tdcr = apic_read(APIC_TDCR);
- apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
+#ifdef CONFIG_X86_MCE_P4THERMAL
+ if (maxlvt >= 5)
+ apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
+#endif

local_irq_save(flags);
disable_local_APIC();
@@ -675,10 +682,13 @@ static int lapic_resume(struct sys_devic
{
unsigned int l, h;
unsigned long flags;
+ int maxlvt;

if (!apic_pm_state.active)
return 0;

+ maxlvt = get_maxlvt();
+
local_irq_save(flags);

/*
@@ -700,8 +710,12 @@ static int lapic_resume(struct sys_devic
apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
- apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
- apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
+#ifdef CONFIG_X86_MCE_P4THERMAL
+ if (maxlvt >= 5)
+ apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
+#endif
+ if (maxlvt >= 4)
+ apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
apic_write(APIC_TDCR, apic_pm_state.apic_tdcr);
apic_write(APIC_TMICT, apic_pm_state.apic_tmict);
--
1.4.2.4


2006-11-18 07:04:35

by Ingo Molnar

[permalink] [raw]
Subject: Re: [PATCH] Regard MSRs in lapic_suspend()/lapic_resume()


* Karsten Wiese <[email protected]> wrote:

> Read/Write APIC_LVTPC and APIC_LVTTHMR only, if get_maxlvt() returns
> certain values. This is done like everywhere else in
> i386/kernel/apic.c, so I guess its correct. Suspends/Resumes to disk
> fine and eleminates an smp_error_interrupt() here on a K8.
>
> Signed-off-by: Karsten Wiese <[email protected]>

nice one! I'm tempted to suggest this for 2.6.19 merge because it causes
the kernel to do less (so it has little risk of breaking something that
is working) ... who knows what happens on certain (older?) APICs when we
try to write back those bogus values.

Acked-by: Ingo Molnar <[email protected]>

Ingo

2006-11-18 07:23:07

by Ingo Molnar

[permalink] [raw]
Subject: Re: [PATCH] Regard MSRs in lapic_suspend()/lapic_resume()


* Ingo Molnar <[email protected]> wrote:

> > Signed-off-by: Karsten Wiese <[email protected]>
>
> nice one! I'm tempted to suggest this for 2.6.19 merge because it
> causes the kernel to do less (so it has little risk of breaking
> something that is working) ... who knows what happens on certain
> (older?) APICs when we try to write back those bogus values.
>
> Acked-by: Ingo Molnar <[email protected]>

Andrew, find below updated-i386-cleanup-apic-code.patch updated to come
after Karsten's patch.

Ingo

-------------------->
From: Thomas Gleixner <[email protected]>

The apic code is quite unstructured and missing a lot of comments.

- Restructure the code into helper functions, timer, setup/shutdown,
interrupt and power management blocks.
- Fixup comments.
- Namespace fixups
- Inline helpers for version and is_integrated
- Combine the ack_bad_irq functions

No functional changes.

Signed-off-by: Thomas Gleixner <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: Zachary Amsden <[email protected]>
Cc: "Eric W. Biederman" <[email protected]>
Cc: Rohit Seth <[email protected]>
Cc: Andi Kleen <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
---
arch/i386/kernel/apic.c | 2071 ++++++++++++++++++++++-----------------------
arch/i386/kernel/io_apic.c | 2
arch/i386/kernel/irq.c | 22
arch/i386/kernel/smpboot.c | 4
include/asm-i386/apic.h | 2
5 files changed, 1075 insertions(+), 1026 deletions(-)

Index: linux/arch/i386/kernel/apic.c
===================================================================
--- linux.orig/arch/i386/kernel/apic.c
+++ linux/arch/i386/kernel/apic.c
@@ -44,6 +44,13 @@
#include "io_ports.h"

/*
+ * Sanity check
+ */
+#if (SPURIOUS_APIC_VECTOR & 0x0F) != 0x0F
+# error SPURIOUS_APIC_VECTOR definition error
+#endif
+
+/*
* cpu_mask that denotes the CPUs that needs timer interrupt coming in as
* IPIs in place of local APIC timers
*/
@@ -51,561 +58,559 @@ static cpumask_t timer_bcast_ipi;

/*
* Knob to control our willingness to enable the local APIC.
+ *
+ * -1=force-disable, +1=force-enable
*/
-static int enable_local_apic __initdata = 0; /* -1=force-disable, +1=force-enable */
-
-static inline void lapic_disable(void)
-{
- enable_local_apic = -1;
- clear_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);
-}
-
-static inline void lapic_enable(void)
-{
- enable_local_apic = 1;
-}
+static int enable_local_apic __initdata = 0;

/*
- * Debug level
+ * Debug level, exported for io_apic.c
*/
int apic_verbosity;

-
static void apic_pm_activate(void);

-static int modern_apic(void)
+
+/* Using APIC to generate smp_local_timer_interrupt? */
+int using_apic_timer __read_mostly = 0;
+
+/* Local APIC was disabled by the BIOS and enabled by the kernel */
+static int enabled_via_apicbase;
+
+/*
+ * Get the LAPIC version
+ */
+static inline int lapic_get_version(void)
{
- unsigned int lvr, version;
- /* AMD systems use old APIC versions, so check the CPU */
- if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
- boot_cpu_data.x86 >= 0xf)
- return 1;
- lvr = apic_read(APIC_LVR);
- version = GET_APIC_VERSION(lvr);
- return version >= 0x14;
+ return GET_APIC_VERSION(apic_read(APIC_LVR));
}

/*
- * 'what should we do if we get a hw irq event on an illegal vector'.
- * each architecture has to answer this themselves.
+ * Check, if the APIC is integrated or a seperate chip
*/
-void ack_bad_irq(unsigned int irq)
+static inline int lapic_is_integrated(void)
{
- printk("unexpected IRQ trap at vector %02x\n", irq);
- /*
- * Currently unexpected vectors happen only on SMP and APIC.
- * We _must_ ack these because every local APIC has only N
- * irq slots per priority level, and a 'hanging, unacked' IRQ
- * holds up an irq slot - in excessive cases (when multiple
- * unexpected vectors occur) that might lock up the APIC
- * completely.
- * But only ack when the APIC is enabled -AK
- */
- if (cpu_has_apic)
- ack_APIC_irq();
+ return APIC_INTEGRATED(lapic_get_version());
}

-void __init apic_intr_init(void)
+/*
+ * Check, whether this is a modern or a first generation APIC
+ */
+static int modern_apic(void)
{
-#ifdef CONFIG_SMP
- smp_intr_init();
-#endif
- /* self generated IPI for local APIC timer */
- set_intr_gate(LOCAL_TIMER_VECTOR, apic_timer_interrupt);
-
- /* IPI vectors for APIC spurious and error interrupts */
- set_intr_gate(SPURIOUS_APIC_VECTOR, spurious_interrupt);
- set_intr_gate(ERROR_APIC_VECTOR, error_interrupt);
-
- /* thermal monitor LVT interrupt */
-#ifdef CONFIG_X86_MCE_P4THERMAL
- set_intr_gate(THERMAL_APIC_VECTOR, thermal_interrupt);
-#endif
+ /* AMD systems use old APIC versions, so check the CPU */
+ if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
+ boot_cpu_data.x86 >= 0xf)
+ return 1;
+ return lapic_get_version() >= 0x14;
}

-/* Using APIC to generate smp_local_timer_interrupt? */
-int using_apic_timer __read_mostly = 0;
-
-static int enabled_via_apicbase;
-
+/**
+ * enable_NMI_through_LVT0 - enable NMI through local vector table 0
+ */
void enable_NMI_through_LVT0 (void * dummy)
{
- unsigned int v, ver;
+ unsigned int v = APIC_DM_NMI;

- ver = apic_read(APIC_LVR);
- ver = GET_APIC_VERSION(ver);
- v = APIC_DM_NMI; /* unmask and set to NMI */
- if (!APIC_INTEGRATED(ver)) /* 82489DX */
+ /* Level triggered for 82489DX */
+ if (!lapic_is_integrated())
v |= APIC_LVT_LEVEL_TRIGGER;
apic_write_around(APIC_LVT0, v);
}

+/**
+ * get_physical_broadcast - Get number of physical broadcast IDs
+ */
int get_physical_broadcast(void)
{
- if (modern_apic())
- return 0xff;
- else
- return 0xf;
+ return modern_apic() ? 0xff : 0xf;
}

-int get_maxlvt(void)
+/**
+ * lapic_get_maxlvt - get the maximum number of local vector table entries
+ */
+int lapic_get_maxlvt(void)
{
- unsigned int v, ver, maxlvt;
+ unsigned int v = apic_read(APIC_LVR);

- v = apic_read(APIC_LVR);
- ver = GET_APIC_VERSION(v);
/* 82489DXs do not report # of LVT entries. */
- maxlvt = APIC_INTEGRATED(ver) ? GET_APIC_MAXLVT(v) : 2;
- return maxlvt;
+ return APIC_INTEGRATED(GET_APIC_VERSION(v)) ? GET_APIC_MAXLVT(v) : 2;
}

-void clear_local_APIC(void)
+/*
+ * Local APIC timer
+ */
+
+/*
+ * This part sets up the APIC 32 bit clock in LVTT1, with HZ interrupts
+ * per second. We assume that the caller has already set up the local
+ * APIC.
+ *
+ * The APIC timer is not exactly sync with the external timer chip, it
+ * closely follows bus clocks.
+ */
+
+/*
+ * The timer chip is already set up at HZ interrupts per second here,
+ * but we do not accept timer interrupts yet. We only allow the BP
+ * to calibrate.
+ */
+static unsigned int __devinit get_8254_timer_count(void)
{
- int maxlvt;
- unsigned long v;
+ unsigned long flags;

- maxlvt = get_maxlvt();
+ unsigned int count;

- /*
- * Masking an LVT entry can trigger a local APIC error
- * if the vector is zero. Mask LVTERR first to prevent this.
- */
- if (maxlvt >= 3) {
- v = ERROR_APIC_VECTOR; /* any non-zero vector will do */
- apic_write_around(APIC_LVTERR, v | APIC_LVT_MASKED);
- }
- /*
- * Careful: we have to set masks only first to deassert
- * any level-triggered sources.
- */
- v = apic_read(APIC_LVTT);
- apic_write_around(APIC_LVTT, v | APIC_LVT_MASKED);
- v = apic_read(APIC_LVT0);
- apic_write_around(APIC_LVT0, v | APIC_LVT_MASKED);
- v = apic_read(APIC_LVT1);
- apic_write_around(APIC_LVT1, v | APIC_LVT_MASKED);
- if (maxlvt >= 4) {
- v = apic_read(APIC_LVTPC);
- apic_write_around(APIC_LVTPC, v | APIC_LVT_MASKED);
- }
+ spin_lock_irqsave(&i8253_lock, flags);

-/* lets not touch this if we didn't frob it */
-#ifdef CONFIG_X86_MCE_P4THERMAL
- if (maxlvt >= 5) {
- v = apic_read(APIC_LVTTHMR);
- apic_write_around(APIC_LVTTHMR, v | APIC_LVT_MASKED);
- }
-#endif
- /*
- * Clean APIC state for other OSs:
- */
- apic_write_around(APIC_LVTT, APIC_LVT_MASKED);
- apic_write_around(APIC_LVT0, APIC_LVT_MASKED);
- apic_write_around(APIC_LVT1, APIC_LVT_MASKED);
- if (maxlvt >= 3)
- apic_write_around(APIC_LVTERR, APIC_LVT_MASKED);
- if (maxlvt >= 4)
- apic_write_around(APIC_LVTPC, APIC_LVT_MASKED);
+ outb_p(0x00, PIT_MODE);
+ count = inb_p(PIT_CH0);
+ count |= inb_p(PIT_CH0) << 8;

-#ifdef CONFIG_X86_MCE_P4THERMAL
- if (maxlvt >= 5)
- apic_write_around(APIC_LVTTHMR, APIC_LVT_MASKED);
-#endif
- v = GET_APIC_VERSION(apic_read(APIC_LVR));
- if (APIC_INTEGRATED(v)) { /* !82489DX */
- if (maxlvt > 3) /* Due to Pentium errata 3AP and 11AP. */
- apic_write(APIC_ESR, 0);
- apic_read(APIC_ESR);
- }
-}
+ spin_unlock_irqrestore(&i8253_lock, flags);

-void __init connect_bsp_APIC(void)
-{
- if (pic_mode) {
- /*
- * Do not trust the local APIC being empty at bootup.
- */
- clear_local_APIC();
- /*
- * PIC mode, enable APIC mode in the IMCR, i.e.
- * connect BSP's local APIC to INT and NMI lines.
- */
- apic_printk(APIC_VERBOSE, "leaving PIC mode, "
- "enabling APIC mode.\n");
- outb(0x70, 0x22);
- outb(0x01, 0x23);
- }
- enable_apic_mode();
+ return count;
}

-void disconnect_bsp_APIC(int virt_wire_setup)
+/* next tick in 8254 can be caught by catching timer wraparound */
+static void __devinit wait_8254_wraparound(void)
{
- if (pic_mode) {
- /*
- * Put the board back into PIC mode (has an effect
- * only on certain older boards). Note that APIC
- * interrupts, including IPIs, won't work beyond
- * this point! The only exception are INIT IPIs.
- */
- apic_printk(APIC_VERBOSE, "disabling APIC mode, "
- "entering PIC mode.\n");
- outb(0x70, 0x22);
- outb(0x00, 0x23);
- }
- else {
- /* Go back to Virtual Wire compatibility mode */
- unsigned long value;
+ unsigned int curr_count, prev_count;

- /* For the spurious interrupt use vector F, and enable it */
- value = apic_read(APIC_SPIV);
- value &= ~APIC_VECTOR_MASK;
- value |= APIC_SPIV_APIC_ENABLED;
- value |= 0xf;
- apic_write_around(APIC_SPIV, value);
+ curr_count = get_8254_timer_count();
+ do {
+ prev_count = curr_count;
+ curr_count = get_8254_timer_count();

- if (!virt_wire_setup) {
- /* For LVT0 make it edge triggered, active high, external and enabled */
- value = apic_read(APIC_LVT0);
- value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
- APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
- APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED );
- value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
- value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_EXTINT);
- apic_write_around(APIC_LVT0, value);
- }
- else {
- /* Disable LVT0 */
- apic_write_around(APIC_LVT0, APIC_LVT_MASKED);
- }
+ /* workaround for broken Mercury/Neptune */
+ if (prev_count >= curr_count + 0x100)
+ curr_count = get_8254_timer_count();

- /* For LVT1 make it edge triggered, active high, nmi and enabled */
- value = apic_read(APIC_LVT1);
- value &= ~(
- APIC_MODE_MASK | APIC_SEND_PENDING |
- APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
- APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
- value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
- value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_NMI);
- apic_write_around(APIC_LVT1, value);
- }
+ } while (prev_count >= curr_count);
}

-void disable_local_APIC(void)
+/*
+ * Default initialization for 8254 timers. If we use other timers like HPET,
+ * we override this later
+ */
+void (*wait_timer_tick)(void) __devinitdata = wait_8254_wraparound;
+
+/*
+ * This function sets up the local APIC timer, with a timeout of
+ * 'clocks' APIC bus clock. During calibration we actually call
+ * this function twice on the boot CPU, once with a bogus timeout
+ * value, second time for real. The other (noncalibrating) CPUs
+ * call this function only once, with the real, calibrated value.
+ *
+ * We do reads before writes even if unnecessary, to get around the
+ * P5 APIC double write bug.
+ */
+
+#define APIC_DIVISOR 16
+
+static void __setup_APIC_LVTT(unsigned int clocks)
{
- unsigned long value;
+ unsigned int lvtt_value, tmp_value;
+ int cpu = smp_processor_id();

- clear_local_APIC();
+ lvtt_value = APIC_LVT_TIMER_PERIODIC | LOCAL_TIMER_VECTOR;
+ if (!lapic_is_integrated())
+ lvtt_value |= SET_APIC_TIMER_BASE(APIC_TIMER_BASE_DIV);
+
+ if (cpu_isset(cpu, timer_bcast_ipi))
+ lvtt_value |= APIC_LVT_MASKED;
+
+ apic_write_around(APIC_LVTT, lvtt_value);

/*
- * Disable APIC (implies clearing of registers
- * for 82489DX!).
+ * Divide PICLK by 16
*/
- value = apic_read(APIC_SPIV);
- value &= ~APIC_SPIV_APIC_ENABLED;
- apic_write_around(APIC_SPIV, value);
+ tmp_value = apic_read(APIC_TDCR);
+ apic_write_around(APIC_TDCR, (tmp_value
+ & ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE))
+ | APIC_TDR_DIV_16);

- if (enabled_via_apicbase) {
- unsigned int l, h;
- rdmsr(MSR_IA32_APICBASE, l, h);
- l &= ~MSR_IA32_APICBASE_ENABLE;
- wrmsr(MSR_IA32_APICBASE, l, h);
- }
+ apic_write_around(APIC_TMICT, clocks/APIC_DIVISOR);
}

-/*
- * This is to verify that we're looking at a real local APIC.
- * Check these against your board if the CPUs aren't getting
- * started for no apparent reason.
- */
-int __init verify_local_APIC(void)
+static void __devinit setup_APIC_timer(unsigned int clocks)
{
- unsigned int reg0, reg1;
+ unsigned long flags;
+
+ local_irq_save(flags);

/*
- * The version register is read-only in a real APIC.
+ * Wait for IRQ0's slice:
*/
- reg0 = apic_read(APIC_LVR);
- apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg0);
- apic_write(APIC_LVR, reg0 ^ APIC_LVR_MASK);
- reg1 = apic_read(APIC_LVR);
- apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg1);
+ wait_timer_tick();
+
+ __setup_APIC_LVTT(clocks);
+
+ local_irq_restore(flags);
+}
+
+/*
+ * In this function we calibrate APIC bus clocks to the external
+ * timer. Unfortunately we cannot use jiffies and the timer irq
+ * to calibrate, since some later bootup code depends on getting
+ * the first irq? Ugh.
+ *
+ * We want to do the calibration only once since we
+ * want to have local timer irqs syncron. CPUs connected
+ * by the same APIC bus have the very same bus frequency.
+ * And we want to have irqs off anyways, no accidental
+ * APIC irq that way.
+ */
+
+static int __init calibrate_APIC_clock(void)
+{
+ unsigned long long t1 = 0, t2 = 0;
+ long tt1, tt2;
+ long result;
+ int i;
+ const int LOOPS = HZ/10;
+
+ apic_printk(APIC_VERBOSE, "calibrating APIC timer ...\n");

/*
- * The two version reads above should print the same
- * numbers. If the second one is different, then we
- * poke at a non-APIC.
+ * Put whatever arbitrary (but long enough) timeout
+ * value into the APIC clock, we just want to get the
+ * counter running for calibration.
*/
- if (reg1 != reg0)
- return 0;
+ __setup_APIC_LVTT(1000000000);

/*
- * Check if the version looks reasonably.
+ * The timer chip counts down to zero. Let's wait
+ * for a wraparound to start exact measurement:
+ * (the current tick might have been already half done)
*/
- reg1 = GET_APIC_VERSION(reg0);
- if (reg1 == 0x00 || reg1 == 0xff)
- return 0;
- reg1 = get_maxlvt();
- if (reg1 < 0x02 || reg1 == 0xff)
- return 0;
+
+ wait_timer_tick();

/*
- * The ID register is read/write in a real APIC.
+ * We wrapped around just now. Let's start:
*/
- reg0 = apic_read(APIC_ID);
- apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg0);
+ if (cpu_has_tsc)
+ rdtscll(t1);
+ tt1 = apic_read(APIC_TMCCT);

/*
- * The next two are just to see if we have sane values.
- * They're only really relevant if we're in Virtual Wire
- * compatibility mode, but most boxes are anymore.
+ * Let's wait LOOPS wraprounds:
*/
- reg0 = apic_read(APIC_LVT0);
- apic_printk(APIC_DEBUG, "Getting LVT0: %x\n", reg0);
- reg1 = apic_read(APIC_LVT1);
- apic_printk(APIC_DEBUG, "Getting LVT1: %x\n", reg1);
+ for (i = 0; i < LOOPS; i++)
+ wait_timer_tick();

- return 1;
-}
+ tt2 = apic_read(APIC_TMCCT);
+ if (cpu_has_tsc)
+ rdtscll(t2);

-void __init sync_Arb_IDs(void)
-{
- /* Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1
- And not needed on AMD */
- if (modern_apic())
- return;
/*
- * Wait for idle.
+ * The APIC bus clock counter is 32 bits only, it
+ * might have overflown, but note that we use signed
+ * longs, thus no extra care needed.
+ *
+ * underflown to be exact, as the timer counts down ;)
*/
- apic_wait_icr_idle();

- apic_printk(APIC_DEBUG, "Synchronizing Arb IDs.\n");
- apic_write_around(APIC_ICR, APIC_DEST_ALLINC | APIC_INT_LEVELTRIG
- | APIC_DM_INIT);
+ result = (tt1-tt2)*APIC_DIVISOR/LOOPS;
+
+ if (cpu_has_tsc)
+ apic_printk(APIC_VERBOSE, "..... CPU clock speed is "
+ "%ld.%04ld MHz.\n",
+ ((long)(t2-t1)/LOOPS)/(1000000/HZ),
+ ((long)(t2-t1)/LOOPS)%(1000000/HZ));
+
+ apic_printk(APIC_VERBOSE, "..... host bus clock speed is "
+ "%ld.%04ld MHz.\n",
+ result/(1000000/HZ),
+ result%(1000000/HZ));
+
+ return result;
}

-extern void __error_in_apic_c (void);
+static unsigned int calibration_result;

-/*
- * An initial setup of the virtual wire mode.
- */
-void __init init_bsp_APIC(void)
+void __init setup_boot_APIC_clock(void)
{
- unsigned long value, ver;
+ unsigned long flags;
+ apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n");
+ using_apic_timer = 1;
+
+ local_irq_save(flags);

+ calibration_result = calibrate_APIC_clock();
/*
- * Don't do the setup now if we have a SMP BIOS as the
- * through-I/O-APIC virtual wire mode might be active.
+ * Now set up the timer for real.
*/
- if (smp_found_config || !cpu_has_apic)
- return;
+ setup_APIC_timer(calibration_result);

- value = apic_read(APIC_LVR);
- ver = GET_APIC_VERSION(value);
+ local_irq_restore(flags);
+}

- /*
- * Do not trust the local APIC being empty at bootup.
- */
- clear_local_APIC();
+void __devinit setup_secondary_APIC_clock(void)
+{
+ setup_APIC_timer(calibration_result);
+}

- /*
- * Enable APIC.
- */
- value = apic_read(APIC_SPIV);
- value &= ~APIC_VECTOR_MASK;
- value |= APIC_SPIV_APIC_ENABLED;
-
- /* This bit is reserved on P4/Xeon and should be cleared */
- if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) && (boot_cpu_data.x86 == 15))
- value &= ~APIC_SPIV_FOCUS_DISABLED;
- else
- value |= APIC_SPIV_FOCUS_DISABLED;
- value |= SPURIOUS_APIC_VECTOR;
- apic_write_around(APIC_SPIV, value);
+void disable_APIC_timer(void)
+{
+ if (using_apic_timer) {
+ unsigned long v;

- /*
- * Set up the virtual wire mode.
- */
- apic_write_around(APIC_LVT0, APIC_DM_EXTINT);
- value = APIC_DM_NMI;
- if (!APIC_INTEGRATED(ver)) /* 82489DX */
- value |= APIC_LVT_LEVEL_TRIGGER;
- apic_write_around(APIC_LVT1, value);
+ v = apic_read(APIC_LVTT);
+ /*
+ * When an illegal vector value (0-15) is written to an LVT
+ * entry and delivery mode is Fixed, the APIC may signal an
+ * illegal vector error, with out regard to whether the mask
+ * bit is set or whether an interrupt is actually seen on
+ * input.
+ *
+ * Boot sequence might call this function when the LVTT has
+ * '0' vector value. So make sure vector field is set to
+ * valid value.
+ */
+ v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
+ apic_write_around(APIC_LVTT, v);
+ }
}

-void __devinit setup_local_APIC(void)
+void enable_APIC_timer(void)
{
- unsigned long oldvalue, value, ver, maxlvt;
- int i, j;
+ int cpu = smp_processor_id();

- /* Pound the ESR really hard over the head with a big hammer - mbligh */
- if (esr_disable) {
- apic_write(APIC_ESR, 0);
- apic_write(APIC_ESR, 0);
- apic_write(APIC_ESR, 0);
- apic_write(APIC_ESR, 0);
+ if (using_apic_timer && !cpu_isset(cpu, timer_bcast_ipi)) {
+ unsigned long v;
+
+ v = apic_read(APIC_LVTT);
+ apic_write_around(APIC_LVTT, v & ~APIC_LVT_MASKED);
+ }
+}
+
+void switch_APIC_timer_to_ipi(void *cpumask)
+{
+ cpumask_t mask = *(cpumask_t *)cpumask;
+ int cpu = smp_processor_id();
+
+ if (cpu_isset(cpu, mask) &&
+ !cpu_isset(cpu, timer_bcast_ipi)) {
+ disable_APIC_timer();
+ cpu_set(cpu, timer_bcast_ipi);
}
+}
+EXPORT_SYMBOL(switch_APIC_timer_to_ipi);
+
+void switch_ipi_to_APIC_timer(void *cpumask)
+{
+ cpumask_t mask = *(cpumask_t *)cpumask;
+ int cpu = smp_processor_id();

- value = apic_read(APIC_LVR);
- ver = GET_APIC_VERSION(value);
+ if (cpu_isset(cpu, mask) &&
+ cpu_isset(cpu, timer_bcast_ipi)) {
+ cpu_clear(cpu, timer_bcast_ipi);
+ enable_APIC_timer();
+ }
+}
+EXPORT_SYMBOL(switch_ipi_to_APIC_timer);

- if ((SPURIOUS_APIC_VECTOR & 0x0f) != 0x0f)
- __error_in_apic_c();
+/*
+ * Local timer interrupt handler. It does both profiling and
+ * process statistics/rescheduling.
+ */
+inline void smp_local_timer_interrupt(void)
+{
+ profile_tick(CPU_PROFILING);
+#ifdef CONFIG_SMP
+ update_process_times(user_mode_vm(get_irq_regs()));
+#endif

/*
- * Double-check whether this APIC is really registered.
+ * We take the 'long' return path, and there every subsystem
+ * grabs the apropriate locks (kernel lock/ irq lock).
+ *
+ * we might want to decouple profiling from the 'long path',
+ * and do the profiling totally in assembly.
+ *
+ * Currently this isn't too much of an issue (performance wise),
+ * we can take more than 100K local irqs per second on a 100 MHz P5.
*/
- if (!apic_id_registered())
- BUG();
+}
+
+/*
+ * Local APIC timer interrupt. This is the most natural way for doing
+ * local interrupts, but local timer interrupts can be emulated by
+ * broadcast interrupts too. [in case the hw doesn't support APIC timers]
+ *
+ * [ if a single-CPU system runs an SMP kernel then we call the local
+ * interrupt as well. Thus we cannot inline the local irq ... ]
+ */
+
+fastcall void smp_apic_timer_interrupt(struct pt_regs *regs)
+{
+ struct pt_regs *old_regs = set_irq_regs(regs);
+ int cpu = smp_processor_id();

/*
- * Intel recommends to set DFR, LDR and TPR before enabling
- * an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel
- * document number 292116). So here it goes...
+ * the NMI deadlock-detector uses this.
*/
- init_apic_ldr();
+ per_cpu(irq_stat, cpu).apic_timer_irqs++;

/*
- * Set Task Priority to 'accept all'. We never change this
- * later on.
+ * NOTE! We'd better ACK the irq immediately,
+ * because timer handling can be slow.
*/
- value = apic_read(APIC_TASKPRI);
- value &= ~APIC_TPRI_MASK;
- apic_write_around(APIC_TASKPRI, value);
-
+ ack_APIC_irq();
/*
- * After a crash, we no longer service the interrupts and a pending
- * interrupt from previous kernel might still have ISR bit set.
- *
- * Most probably by now CPU has serviced that pending interrupt and
- * it might not have done the ack_APIC_irq() because it thought,
- * interrupt came from i8259 as ExtInt. LAPIC did not get EOI so it
- * does not clear the ISR bit and cpu thinks it has already serivced
- * the interrupt. Hence a vector might get locked. It was noticed
- * for timer irq (vector 0x31). Issue an extra EOI to clear ISR.
+ * update_process_times() expects us to have done irq_enter().
+ * Besides, if we don't timer interrupts ignore the global
+ * interrupt lock, which is the WrongThing (tm) to do.
*/
- for (i = APIC_ISR_NR - 1; i >= 0; i--) {
- value = apic_read(APIC_ISR + i*0x10);
- for (j = 31; j >= 0; j--) {
- if (value & (1<<j))
- ack_APIC_irq();
- }
- }
+ irq_enter();
+ smp_local_timer_interrupt();
+ irq_exit();
+ set_irq_regs(old_regs);
+}

- /*
- * Now that we are all set up, enable the APIC
- */
- value = apic_read(APIC_SPIV);
- value &= ~APIC_VECTOR_MASK;
- /*
- * Enable APIC
- */
- value |= APIC_SPIV_APIC_ENABLED;
+#ifndef CONFIG_SMP
+static void up_apic_timer_interrupt_call(void)
+{
+ int cpu = smp_processor_id();

/*
- * Some unknown Intel IO/APIC (or APIC) errata is biting us with
- * certain networking cards. If high frequency interrupts are
- * happening on a particular IOAPIC pin, plus the IOAPIC routing
- * entry is masked/unmasked at a high rate as well then sooner or
- * later IOAPIC line gets 'stuck', no more interrupts are received
- * from the device. If focus CPU is disabled then the hang goes
- * away, oh well :-(
- *
- * [ This bug can be reproduced easily with a level-triggered
- * PCI Ne2000 networking cards and PII/PIII processors, dual
- * BX chipset. ]
- */
- /*
- * Actually disabling the focus CPU check just makes the hang less
- * frequent as it makes the interrupt distributon model be more
- * like LRU than MRU (the short-term load is more even across CPUs).
- * See also the comment in end_level_ioapic_irq(). --macro
+ * the NMI deadlock-detector uses this.
*/
-#if 1
- /* Enable focus processor (bit==0) */
- value &= ~APIC_SPIV_FOCUS_DISABLED;
+ per_cpu(irq_stat, cpu).apic_timer_irqs++;
+
+ smp_local_timer_interrupt();
+}
+#endif
+
+void smp_send_timer_broadcast_ipi(void)
+{
+ cpumask_t mask;
+
+ cpus_and(mask, cpu_online_map, timer_bcast_ipi);
+ if (!cpus_empty(mask)) {
+#ifdef CONFIG_SMP
+ send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
#else
- /* Disable focus processor (bit==1) */
- value |= APIC_SPIV_FOCUS_DISABLED;
+ /*
+ * We can directly call the apic timer interrupt handler
+ * in UP case. Minus all irq related functions
+ */
+ up_apic_timer_interrupt_call();
#endif
- /*
- * Set spurious IRQ vector
- */
- value |= SPURIOUS_APIC_VECTOR;
- apic_write_around(APIC_SPIV, value);
+ }
+}
+
+int setup_profiling_timer(unsigned int multiplier)
+{
+ return -EINVAL;
+}
+
+/*
+ * Local APIC start and shutdown
+ */
+
+/**
+ * clear_local_APIC - shutdown the local APIC
+ *
+ * This is called, when a CPU is disabled and before rebooting, so the state of
+ * the local APIC has no dangling leftovers. Also used to cleanout any BIOS
+ * leftovers during boot.
+ */
+void clear_local_APIC(void)
+{
+ int maxlvt = lapic_get_maxlvt();
+ unsigned long v;

/*
- * Set up LVT0, LVT1:
- *
- * set up through-local-APIC on the BP's LINT0. This is not
- * strictly necessery in pure symmetric-IO mode, but sometimes
- * we delegate interrupts to the 8259A.
+ * Masking an LVT entry can trigger a local APIC error
+ * if the vector is zero. Mask LVTERR first to prevent this.
*/
+ if (maxlvt >= 3) {
+ v = ERROR_APIC_VECTOR; /* any non-zero vector will do */
+ apic_write_around(APIC_LVTERR, v | APIC_LVT_MASKED);
+ }
/*
- * TODO: set up through-local-APIC from through-I/O-APIC? --macro
+ * Careful: we have to set masks only first to deassert
+ * any level-triggered sources.
*/
- value = apic_read(APIC_LVT0) & APIC_LVT_MASKED;
- if (!smp_processor_id() && (pic_mode || !value)) {
- value = APIC_DM_EXTINT;
- apic_printk(APIC_VERBOSE, "enabled ExtINT on CPU#%d\n",
- smp_processor_id());
- } else {
- value = APIC_DM_EXTINT | APIC_LVT_MASKED;
- apic_printk(APIC_VERBOSE, "masked ExtINT on CPU#%d\n",
- smp_processor_id());
+ v = apic_read(APIC_LVTT);
+ apic_write_around(APIC_LVTT, v | APIC_LVT_MASKED);
+ v = apic_read(APIC_LVT0);
+ apic_write_around(APIC_LVT0, v | APIC_LVT_MASKED);
+ v = apic_read(APIC_LVT1);
+ apic_write_around(APIC_LVT1, v | APIC_LVT_MASKED);
+ if (maxlvt >= 4) {
+ v = apic_read(APIC_LVTPC);
+ apic_write_around(APIC_LVTPC, v | APIC_LVT_MASKED);
}
- apic_write_around(APIC_LVT0, value);

+ /* lets not touch this if we didn't frob it */
+#ifdef CONFIG_X86_MCE_P4THERMAL
+ if (maxlvt >= 5) {
+ v = apic_read(APIC_LVTTHMR);
+ apic_write_around(APIC_LVTTHMR, v | APIC_LVT_MASKED);
+ }
+#endif
/*
- * only the BP should see the LINT1 NMI signal, obviously.
+ * Clean APIC state for other OSs:
*/
- if (!smp_processor_id())
- value = APIC_DM_NMI;
- else
- value = APIC_DM_NMI | APIC_LVT_MASKED;
- if (!APIC_INTEGRATED(ver)) /* 82489DX */
- value |= APIC_LVT_LEVEL_TRIGGER;
- apic_write_around(APIC_LVT1, value);
-
- if (APIC_INTEGRATED(ver) && !esr_disable) { /* !82489DX */
- maxlvt = get_maxlvt();
- if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
- apic_write(APIC_ESR, 0);
- oldvalue = apic_read(APIC_ESR);
+ apic_write_around(APIC_LVTT, APIC_LVT_MASKED);
+ apic_write_around(APIC_LVT0, APIC_LVT_MASKED);
+ apic_write_around(APIC_LVT1, APIC_LVT_MASKED);
+ if (maxlvt >= 3)
+ apic_write_around(APIC_LVTERR, APIC_LVT_MASKED);
+ if (maxlvt >= 4)
+ apic_write_around(APIC_LVTPC, APIC_LVT_MASKED);

- value = ERROR_APIC_VECTOR; // enables sending errors
- apic_write_around(APIC_LVTERR, value);
- /*
- * spec says clear errors after enabling vector.
- */
+#ifdef CONFIG_X86_MCE_P4THERMAL
+ if (maxlvt >= 5)
+ apic_write_around(APIC_LVTTHMR, APIC_LVT_MASKED);
+#endif
+ /* Integrated APIC (!82489DX) ? */
+ if (lapic_is_integrated()) {
if (maxlvt > 3)
+ /* Clear ESR due to Pentium errata 3AP and 11AP */
apic_write(APIC_ESR, 0);
- value = apic_read(APIC_ESR);
- if (value != oldvalue)
- apic_printk(APIC_VERBOSE, "ESR value before enabling "
- "vector: 0x%08lx after: 0x%08lx\n",
- oldvalue, value);
- } else {
- if (esr_disable)
- /*
- * Something untraceble is creating bad interrupts on
- * secondary quads ... for the moment, just leave the
- * ESR disabled - we can't do anything useful with the
- * errors anyway - mbligh
- */
- printk("Leaving ESR disabled.\n");
- else
- printk("No ESR for 82489DX.\n");
+ apic_read(APIC_ESR);
}
+}

- setup_apic_nmi_watchdog(NULL);
- apic_pm_activate();
+/**
+ * disable_local_APIC - clear and disable the local APIC
+ */
+void disable_local_APIC(void)
+{
+ unsigned long value;
+
+ clear_local_APIC();
+
+ /*
+ * Disable APIC (implies clearing of registers
+ * for 82489DX!).
+ */
+ value = apic_read(APIC_SPIV);
+ value &= ~APIC_SPIV_APIC_ENABLED;
+ apic_write_around(APIC_SPIV, value);
+
+ /*
+ * When LAPIC was disabled by the BIOS and enabled by the kernel,
+ * restore the disabled state.
+ */
+ if (enabled_via_apicbase) {
+ unsigned int l, h;
+
+ rdmsr(MSR_IA32_APICBASE, l, h);
+ l &= ~MSR_IA32_APICBASE_ENABLE;
+ wrmsr(MSR_IA32_APICBASE, l, h);
+ }
}

/*
- * If Linux enabled the LAPIC against the BIOS default
- * disable it down before re-entering the BIOS on shutdown.
- * Otherwise the BIOS may get confused and not power-off.
- * Additionally clear all LVT entries before disable_local_APIC
+ * If Linux enabled the LAPIC against the BIOS default disable it down before
+ * re-entering the BIOS on shutdown. Otherwise the BIOS may get confused and
+ * not power-off. Additionally clear all LVT entries before disable_local_APIC
* for the case where Linux didn't enable the LAPIC.
*/
void lapic_shutdown(void)
@@ -624,168 +629,296 @@ void lapic_shutdown(void)
local_irq_restore(flags);
}

-#ifdef CONFIG_PM
-
-static struct {
- int active;
- /* r/w apic fields */
- unsigned int apic_id;
- unsigned int apic_taskpri;
- unsigned int apic_ldr;
- unsigned int apic_dfr;
- unsigned int apic_spiv;
- unsigned int apic_lvtt;
- unsigned int apic_lvtpc;
- unsigned int apic_lvt0;
- unsigned int apic_lvt1;
- unsigned int apic_lvterr;
- unsigned int apic_tmict;
- unsigned int apic_tdcr;
- unsigned int apic_thmr;
-} apic_pm_state;
-
-static int lapic_suspend(struct sys_device *dev, pm_message_t state)
+/*
+ * This is to verify that we're looking at a real local APIC.
+ * Check these against your board if the CPUs aren't getting
+ * started for no apparent reason.
+ */
+int __init verify_local_APIC(void)
{
- unsigned long flags;
- int maxlvt;
+ unsigned int reg0, reg1;

- if (!apic_pm_state.active)
+ /*
+ * The version register is read-only in a real APIC.
+ */
+ reg0 = apic_read(APIC_LVR);
+ apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg0);
+ apic_write(APIC_LVR, reg0 ^ APIC_LVR_MASK);
+ reg1 = apic_read(APIC_LVR);
+ apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg1);
+
+ /*
+ * The two version reads above should print the same
+ * numbers. If the second one is different, then we
+ * poke at a non-APIC.
+ */
+ if (reg1 != reg0)
return 0;

- maxlvt = get_maxlvt();
+ /*
+ * Check if the version looks reasonably.
+ */
+ reg1 = GET_APIC_VERSION(reg0);
+ if (reg1 == 0x00 || reg1 == 0xff)
+ return 0;
+ reg1 = lapic_get_maxlvt();
+ if (reg1 < 0x02 || reg1 == 0xff)
+ return 0;

- apic_pm_state.apic_id = apic_read(APIC_ID);
- apic_pm_state.apic_taskpri = apic_read(APIC_TASKPRI);
- apic_pm_state.apic_ldr = apic_read(APIC_LDR);
- apic_pm_state.apic_dfr = apic_read(APIC_DFR);
- apic_pm_state.apic_spiv = apic_read(APIC_SPIV);
- apic_pm_state.apic_lvtt = apic_read(APIC_LVTT);
- if (maxlvt >= 4)
- apic_pm_state.apic_lvtpc = apic_read(APIC_LVTPC);
- apic_pm_state.apic_lvt0 = apic_read(APIC_LVT0);
- apic_pm_state.apic_lvt1 = apic_read(APIC_LVT1);
- apic_pm_state.apic_lvterr = apic_read(APIC_LVTERR);
- apic_pm_state.apic_tmict = apic_read(APIC_TMICT);
- apic_pm_state.apic_tdcr = apic_read(APIC_TDCR);
-#ifdef CONFIG_X86_MCE_P4THERMAL
- if (maxlvt >= 5)
- apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
-#endif
-
- local_irq_save(flags);
- disable_local_APIC();
- local_irq_restore(flags);
- return 0;
+ /*
+ * The ID register is read/write in a real APIC.
+ */
+ reg0 = apic_read(APIC_ID);
+ apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg0);
+
+ /*
+ * The next two are just to see if we have sane values.
+ * They're only really relevant if we're in Virtual Wire
+ * compatibility mode, but most boxes are anymore.
+ */
+ reg0 = apic_read(APIC_LVT0);
+ apic_printk(APIC_DEBUG, "Getting LVT0: %x\n", reg0);
+ reg1 = apic_read(APIC_LVT1);
+ apic_printk(APIC_DEBUG, "Getting LVT1: %x\n", reg1);
+
+ return 1;
}

-static int lapic_resume(struct sys_device *dev)
+/**
+ * sync_Arb_IDs - synchronize APIC bus arbitration IDs
+ */
+void __init sync_Arb_IDs(void)
{
- unsigned int l, h;
- unsigned long flags;
- int maxlvt;
+ /*
+ * Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1 And not
+ * needed on AMD.
+ */
+ if (modern_apic())
+ return;
+ /*
+ * Wait for idle.
+ */
+ apic_wait_icr_idle();

- if (!apic_pm_state.active)
- return 0;
+ apic_printk(APIC_DEBUG, "Synchronizing Arb IDs.\n");
+ apic_write_around(APIC_ICR, APIC_DEST_ALLINC | APIC_INT_LEVELTRIG
+ | APIC_DM_INIT);
+}

- maxlvt = get_maxlvt();
+/*
+ * An initial setup of the virtual wire mode.
+ */
+void __init init_bsp_APIC(void)
+{
+ unsigned long value;

- local_irq_save(flags);
+ /*
+ * Don't do the setup now if we have a SMP BIOS as the
+ * through-I/O-APIC virtual wire mode might be active.
+ */
+ if (smp_found_config || !cpu_has_apic)
+ return;

/*
- * Make sure the APICBASE points to the right address
- *
- * FIXME! This will be wrong if we ever support suspend on
- * SMP! We'll need to do this as part of the CPU restore!
+ * Do not trust the local APIC being empty at bootup.
*/
- rdmsr(MSR_IA32_APICBASE, l, h);
- l &= ~MSR_IA32_APICBASE_BASE;
- l |= MSR_IA32_APICBASE_ENABLE | mp_lapic_addr;
- wrmsr(MSR_IA32_APICBASE, l, h);
+ clear_local_APIC();

- apic_write(APIC_LVTERR, ERROR_APIC_VECTOR | APIC_LVT_MASKED);
- apic_write(APIC_ID, apic_pm_state.apic_id);
- apic_write(APIC_DFR, apic_pm_state.apic_dfr);
- apic_write(APIC_LDR, apic_pm_state.apic_ldr);
- apic_write(APIC_TASKPRI, apic_pm_state.apic_taskpri);
- apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
- apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
- apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
-#ifdef CONFIG_X86_MCE_P4THERMAL
- if (maxlvt >= 5)
- apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
-#endif
- if (maxlvt >= 4)
- apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
- apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
- apic_write(APIC_TDCR, apic_pm_state.apic_tdcr);
- apic_write(APIC_TMICT, apic_pm_state.apic_tmict);
- apic_write(APIC_ESR, 0);
- apic_read(APIC_ESR);
- apic_write(APIC_LVTERR, apic_pm_state.apic_lvterr);
- apic_write(APIC_ESR, 0);
- apic_read(APIC_ESR);
- local_irq_restore(flags);
- return 0;
+ /*
+ * Enable APIC.
+ */
+ value = apic_read(APIC_SPIV);
+ value &= ~APIC_VECTOR_MASK;
+ value |= APIC_SPIV_APIC_ENABLED;
+
+ /* This bit is reserved on P4/Xeon and should be cleared */
+ if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
+ (boot_cpu_data.x86 == 15))
+ value &= ~APIC_SPIV_FOCUS_DISABLED;
+ else
+ value |= APIC_SPIV_FOCUS_DISABLED;
+ value |= SPURIOUS_APIC_VECTOR;
+ apic_write_around(APIC_SPIV, value);
+
+ /*
+ * Set up the virtual wire mode.
+ */
+ apic_write_around(APIC_LVT0, APIC_DM_EXTINT);
+ value = APIC_DM_NMI;
+ if (!lapic_is_integrated()) /* 82489DX */
+ value |= APIC_LVT_LEVEL_TRIGGER;
+ apic_write_around(APIC_LVT1, value);
}

-/*
- * This device has no shutdown method - fully functioning local APICs
- * are needed on every CPU up until machine_halt/restart/poweroff.
+/**
+ * setup_local_APIC - setup the local APIC
*/
+void __devinit setup_local_APIC(void)
+{
+ unsigned long oldvalue, value, maxlvt, integrated;
+ int i, j;

-static struct sysdev_class lapic_sysclass = {
- set_kset_name("lapic"),
- .resume = lapic_resume,
- .suspend = lapic_suspend,
-};
+ /* Pound the ESR really hard over the head with a big hammer - mbligh */
+ if (esr_disable) {
+ apic_write(APIC_ESR, 0);
+ apic_write(APIC_ESR, 0);
+ apic_write(APIC_ESR, 0);
+ apic_write(APIC_ESR, 0);
+ }

-static struct sys_device device_lapic = {
- .id = 0,
- .cls = &lapic_sysclass,
-};
+ integrated = lapic_is_integrated();

-static void __devinit apic_pm_activate(void)
-{
- apic_pm_state.active = 1;
-}
+ /*
+ * Double-check whether this APIC is really registered.
+ */
+ if (!apic_id_registered())
+ BUG();

-static int __init init_lapic_sysfs(void)
-{
- int error;
+ /*
+ * Intel recommends to set DFR, LDR and TPR before enabling
+ * an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel
+ * document number 292116). So here it goes...
+ */
+ init_apic_ldr();

- if (!cpu_has_apic)
- return 0;
- /* XXX: remove suspend/resume procs if !apic_pm_state.active? */
+ /*
+ * Set Task Priority to 'accept all'. We never change this
+ * later on.
+ */
+ value = apic_read(APIC_TASKPRI);
+ value &= ~APIC_TPRI_MASK;
+ apic_write_around(APIC_TASKPRI, value);

- error = sysdev_class_register(&lapic_sysclass);
- if (!error)
- error = sysdev_register(&device_lapic);
- return error;
-}
-device_initcall(init_lapic_sysfs);
+ /*
+ * After a crash, we no longer service the interrupts and a pending
+ * interrupt from previous kernel might still have ISR bit set.
+ *
+ * Most probably by now CPU has serviced that pending interrupt and
+ * it might not have done the ack_APIC_irq() because it thought,
+ * interrupt came from i8259 as ExtInt. LAPIC did not get EOI so it
+ * does not clear the ISR bit and cpu thinks it has already serivced
+ * the interrupt. Hence a vector might get locked. It was noticed
+ * for timer irq (vector 0x31). Issue an extra EOI to clear ISR.
+ */
+ for (i = APIC_ISR_NR - 1; i >= 0; i--) {
+ value = apic_read(APIC_ISR + i*0x10);
+ for (j = 31; j >= 0; j--) {
+ if (value & (1<<j))
+ ack_APIC_irq();
+ }
+ }

-#else /* CONFIG_PM */
+ /*
+ * Now that we are all set up, enable the APIC
+ */
+ value = apic_read(APIC_SPIV);
+ value &= ~APIC_VECTOR_MASK;
+ /*
+ * Enable APIC
+ */
+ value |= APIC_SPIV_APIC_ENABLED;

-static void apic_pm_activate(void) { }
+ /*
+ * Some unknown Intel IO/APIC (or APIC) errata is biting us with
+ * certain networking cards. If high frequency interrupts are
+ * happening on a particular IOAPIC pin, plus the IOAPIC routing
+ * entry is masked/unmasked at a high rate as well then sooner or
+ * later IOAPIC line gets 'stuck', no more interrupts are received
+ * from the device. If focus CPU is disabled then the hang goes
+ * away, oh well :-(
+ *
+ * [ This bug can be reproduced easily with a level-triggered
+ * PCI Ne2000 networking cards and PII/PIII processors, dual
+ * BX chipset. ]
+ */
+ /*
+ * Actually disabling the focus CPU check just makes the hang less
+ * frequent as it makes the interrupt distributon model be more
+ * like LRU than MRU (the short-term load is more even across CPUs).
+ * See also the comment in end_level_ioapic_irq(). --macro
+ */

-#endif /* CONFIG_PM */
+ /* Enable focus processor (bit==0) */
+ value &= ~APIC_SPIV_FOCUS_DISABLED;

-/*
- * Detect and enable local APICs on non-SMP boards.
- * Original code written by Keir Fraser.
- */
+ /*
+ * Set spurious IRQ vector
+ */
+ value |= SPURIOUS_APIC_VECTOR;
+ apic_write_around(APIC_SPIV, value);
+
+ /*
+ * Set up LVT0, LVT1:
+ *
+ * set up through-local-APIC on the BP's LINT0. This is not
+ * strictly necessery in pure symmetric-IO mode, but sometimes
+ * we delegate interrupts to the 8259A.
+ */
+ /*
+ * TODO: set up through-local-APIC from through-I/O-APIC? --macro
+ */
+ value = apic_read(APIC_LVT0) & APIC_LVT_MASKED;
+ if (!smp_processor_id() && (pic_mode || !value)) {
+ value = APIC_DM_EXTINT;
+ apic_printk(APIC_VERBOSE, "enabled ExtINT on CPU#%d\n",
+ smp_processor_id());
+ } else {
+ value = APIC_DM_EXTINT | APIC_LVT_MASKED;
+ apic_printk(APIC_VERBOSE, "masked ExtINT on CPU#%d\n",
+ smp_processor_id());
+ }
+ apic_write_around(APIC_LVT0, value);
+
+ /*
+ * only the BP should see the LINT1 NMI signal, obviously.
+ */
+ if (!smp_processor_id())
+ value = APIC_DM_NMI;
+ else
+ value = APIC_DM_NMI | APIC_LVT_MASKED;
+ if (!integrated) /* 82489DX */
+ value |= APIC_LVT_LEVEL_TRIGGER;
+ apic_write_around(APIC_LVT1, value);
+
+ if (integrated && !esr_disable) { /* !82489DX */
+ maxlvt = lapic_get_maxlvt();
+ if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
+ apic_write(APIC_ESR, 0);
+ oldvalue = apic_read(APIC_ESR);
+
+ /* enables sending errors */
+ value = ERROR_APIC_VECTOR;
+ apic_write_around(APIC_LVTERR, value);
+ /*
+ * spec says clear errors after enabling vector.
+ */
+ if (maxlvt > 3)
+ apic_write(APIC_ESR, 0);
+ value = apic_read(APIC_ESR);
+ if (value != oldvalue)
+ apic_printk(APIC_VERBOSE, "ESR value before enabling "
+ "vector: 0x%08lx after: 0x%08lx\n",
+ oldvalue, value);
+ } else {
+ if (esr_disable)
+ /*
+ * Something untraceble is creating bad interrupts on
+ * secondary quads ... for the moment, just leave the
+ * ESR disabled - we can't do anything useful with the
+ * errors anyway - mbligh
+ */
+ printk(KERN_INFO "Leaving ESR disabled.\n");
+ else
+ printk(KERN_INFO "No ESR for 82489DX.\n");
+ }

-static int __init apic_set_verbosity(char *str)
-{
- if (strcmp("debug", str) == 0)
- apic_verbosity = APIC_DEBUG;
- else if (strcmp("verbose", str) == 0)
- apic_verbosity = APIC_VERBOSE;
- return 1;
+ setup_apic_nmi_watchdog(NULL);
+ apic_pm_activate();
}

-__setup("apic=", apic_set_verbosity);
-
+/*
+ * Detect and initialize APIC
+ */
static int __init detect_init_APIC (void)
{
u32 h, l, features;
@@ -797,7 +930,7 @@ static int __init detect_init_APIC (void
switch (boot_cpu_data.x86_vendor) {
case X86_VENDOR_AMD:
if ((boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model > 1) ||
- (boot_cpu_data.x86 == 15))
+ (boot_cpu_data.x86 == 15))
break;
goto no_apic;
case X86_VENDOR_INTEL:
@@ -811,23 +944,23 @@ static int __init detect_init_APIC (void

if (!cpu_has_apic) {
/*
- * Over-ride BIOS and try to enable the local
- * APIC only if "lapic" specified.
+ * Over-ride BIOS and try to enable the local APIC only if
+ * "lapic" specified.
*/
if (enable_local_apic <= 0) {
- printk("Local APIC disabled by BIOS -- "
+ printk(KERN_INFO "Local APIC disabled by BIOS -- "
"you can enable it with \"lapic\"\n");
return -1;
}
/*
- * Some BIOSes disable the local APIC in the
- * APIC_BASE MSR. This can only be done in
- * software for Intel P6 or later and AMD K7
- * (Model > 1) or later.
+ * Some BIOSes disable the local APIC in the APIC_BASE
+ * MSR. This can only be done in software for Intel P6 or later
+ * and AMD K7 (Model > 1) or later.
*/
rdmsr(MSR_IA32_APICBASE, l, h);
if (!(l & MSR_IA32_APICBASE_ENABLE)) {
- printk("Local APIC disabled by BIOS -- reenabling.\n");
+ printk(KERN_INFO
+ "Local APIC disabled by BIOS -- reenabling.\n");
l &= ~MSR_IA32_APICBASE_BASE;
l |= MSR_IA32_APICBASE_ENABLE | APIC_DEFAULT_PHYS_BASE;
wrmsr(MSR_IA32_APICBASE, l, h);
@@ -840,463 +973,174 @@ static int __init detect_init_APIC (void
*/
features = cpuid_edx(1);
if (!(features & (1 << X86_FEATURE_APIC))) {
- printk("Could not enable APIC!\n");
+ printk(KERN_WARNING "Could not enable APIC!\n");
return -1;
}
set_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);
mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;

/* The BIOS may have set up the APIC at some other address */
- rdmsr(MSR_IA32_APICBASE, l, h);
- if (l & MSR_IA32_APICBASE_ENABLE)
- mp_lapic_addr = l & MSR_IA32_APICBASE_BASE;
-
- if (nmi_watchdog != NMI_NONE)
- nmi_watchdog = NMI_LOCAL_APIC;
-
- printk("Found and enabled local APIC!\n");
-
- apic_pm_activate();
-
- return 0;
-
-no_apic:
- printk("No local APIC present or hardware disabled\n");
- return -1;
-}
-
-void __init init_apic_mappings(void)
-{
- unsigned long apic_phys;
-
- /*
- * If no local APIC can be found then set up a fake all
- * zeroes page to simulate the local APIC and another
- * one for the IO-APIC.
- */
- if (!smp_found_config && detect_init_APIC()) {
- apic_phys = (unsigned long) alloc_bootmem_pages(PAGE_SIZE);
- apic_phys = __pa(apic_phys);
- } else
- apic_phys = mp_lapic_addr;
-
- set_fixmap_nocache(FIX_APIC_BASE, apic_phys);
- printk(KERN_DEBUG "mapped APIC to %08lx (%08lx)\n", APIC_BASE,
- apic_phys);
-
- /*
- * Fetch the APIC ID of the BSP in case we have a
- * default configuration (or the MP table is broken).
- */
- if (boot_cpu_physical_apicid == -1U)
- boot_cpu_physical_apicid = GET_APIC_ID(apic_read(APIC_ID));
-
-#ifdef CONFIG_X86_IO_APIC
- {
- unsigned long ioapic_phys, idx = FIX_IO_APIC_BASE_0;
- int i;
-
- for (i = 0; i < nr_ioapics; i++) {
- if (smp_found_config) {
- ioapic_phys = mp_ioapics[i].mpc_apicaddr;
- if (!ioapic_phys) {
- printk(KERN_ERR
- "WARNING: bogus zero IO-APIC "
- "address found in MPTABLE, "
- "disabling IO/APIC support!\n");
- smp_found_config = 0;
- skip_ioapic_setup = 1;
- goto fake_ioapic_page;
- }
- } else {
-fake_ioapic_page:
- ioapic_phys = (unsigned long)
- alloc_bootmem_pages(PAGE_SIZE);
- ioapic_phys = __pa(ioapic_phys);
- }
- set_fixmap_nocache(idx, ioapic_phys);
- printk(KERN_DEBUG "mapped IOAPIC to %08lx (%08lx)\n",
- __fix_to_virt(idx), ioapic_phys);
- idx++;
- }
- }
-#endif
-}
-
-/*
- * This part sets up the APIC 32 bit clock in LVTT1, with HZ interrupts
- * per second. We assume that the caller has already set up the local
- * APIC.
- *
- * The APIC timer is not exactly sync with the external timer chip, it
- * closely follows bus clocks.
- */
-
-/*
- * The timer chip is already set up at HZ interrupts per second here,
- * but we do not accept timer interrupts yet. We only allow the BP
- * to calibrate.
- */
-static unsigned int __devinit get_8254_timer_count(void)
-{
- unsigned long flags;
-
- unsigned int count;
-
- spin_lock_irqsave(&i8253_lock, flags);
-
- outb_p(0x00, PIT_MODE);
- count = inb_p(PIT_CH0);
- count |= inb_p(PIT_CH0) << 8;
-
- spin_unlock_irqrestore(&i8253_lock, flags);
-
- return count;
-}
-
-/* next tick in 8254 can be caught by catching timer wraparound */
-static void __devinit wait_8254_wraparound(void)
-{
- unsigned int curr_count, prev_count;
-
- curr_count = get_8254_timer_count();
- do {
- prev_count = curr_count;
- curr_count = get_8254_timer_count();
-
- /* workaround for broken Mercury/Neptune */
- if (prev_count >= curr_count + 0x100)
- curr_count = get_8254_timer_count();
-
- } while (prev_count >= curr_count);
-}
-
-/*
- * Default initialization for 8254 timers. If we use other timers like HPET,
- * we override this later
- */
-void (*wait_timer_tick)(void) __devinitdata = wait_8254_wraparound;
-
-/*
- * This function sets up the local APIC timer, with a timeout of
- * 'clocks' APIC bus clock. During calibration we actually call
- * this function twice on the boot CPU, once with a bogus timeout
- * value, second time for real. The other (noncalibrating) CPUs
- * call this function only once, with the real, calibrated value.
- *
- * We do reads before writes even if unnecessary, to get around the
- * P5 APIC double write bug.
- */
-
-#define APIC_DIVISOR 16
-
-static void __setup_APIC_LVTT(unsigned int clocks)
-{
- unsigned int lvtt_value, tmp_value, ver;
- int cpu = smp_processor_id();
-
- ver = GET_APIC_VERSION(apic_read(APIC_LVR));
- lvtt_value = APIC_LVT_TIMER_PERIODIC | LOCAL_TIMER_VECTOR;
- if (!APIC_INTEGRATED(ver))
- lvtt_value |= SET_APIC_TIMER_BASE(APIC_TIMER_BASE_DIV);
-
- if (cpu_isset(cpu, timer_bcast_ipi))
- lvtt_value |= APIC_LVT_MASKED;
-
- apic_write_around(APIC_LVTT, lvtt_value);
-
- /*
- * Divide PICLK by 16
- */
- tmp_value = apic_read(APIC_TDCR);
- apic_write_around(APIC_TDCR, (tmp_value
- & ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE))
- | APIC_TDR_DIV_16);
-
- apic_write_around(APIC_TMICT, clocks/APIC_DIVISOR);
-}
-
-static void __devinit setup_APIC_timer(unsigned int clocks)
-{
- unsigned long flags;
-
- local_irq_save(flags);
-
- /*
- * Wait for IRQ0's slice:
- */
- wait_timer_tick();
-
- __setup_APIC_LVTT(clocks);
-
- local_irq_restore(flags);
-}
-
-/*
- * In this function we calibrate APIC bus clocks to the external
- * timer. Unfortunately we cannot use jiffies and the timer irq
- * to calibrate, since some later bootup code depends on getting
- * the first irq? Ugh.
- *
- * We want to do the calibration only once since we
- * want to have local timer irqs syncron. CPUs connected
- * by the same APIC bus have the very same bus frequency.
- * And we want to have irqs off anyways, no accidental
- * APIC irq that way.
- */
-
-static int __init calibrate_APIC_clock(void)
-{
- unsigned long long t1 = 0, t2 = 0;
- long tt1, tt2;
- long result;
- int i;
- const int LOOPS = HZ/10;
-
- apic_printk(APIC_VERBOSE, "calibrating APIC timer ...\n");
-
- /*
- * Put whatever arbitrary (but long enough) timeout
- * value into the APIC clock, we just want to get the
- * counter running for calibration.
- */
- __setup_APIC_LVTT(1000000000);
-
- /*
- * The timer chip counts down to zero. Let's wait
- * for a wraparound to start exact measurement:
- * (the current tick might have been already half done)
- */
-
- wait_timer_tick();
-
- /*
- * We wrapped around just now. Let's start:
- */
- if (cpu_has_tsc)
- rdtscll(t1);
- tt1 = apic_read(APIC_TMCCT);
-
- /*
- * Let's wait LOOPS wraprounds:
- */
- for (i = 0; i < LOOPS; i++)
- wait_timer_tick();
-
- tt2 = apic_read(APIC_TMCCT);
- if (cpu_has_tsc)
- rdtscll(t2);
-
- /*
- * The APIC bus clock counter is 32 bits only, it
- * might have overflown, but note that we use signed
- * longs, thus no extra care needed.
- *
- * underflown to be exact, as the timer counts down ;)
- */
+ rdmsr(MSR_IA32_APICBASE, l, h);
+ if (l & MSR_IA32_APICBASE_ENABLE)
+ mp_lapic_addr = l & MSR_IA32_APICBASE_BASE;

- result = (tt1-tt2)*APIC_DIVISOR/LOOPS;
+ if (nmi_watchdog != NMI_NONE)
+ nmi_watchdog = NMI_LOCAL_APIC;

- if (cpu_has_tsc)
- apic_printk(APIC_VERBOSE, "..... CPU clock speed is "
- "%ld.%04ld MHz.\n",
- ((long)(t2-t1)/LOOPS)/(1000000/HZ),
- ((long)(t2-t1)/LOOPS)%(1000000/HZ));
+ printk(KERN_INFO "Found and enabled local APIC!\n");

- apic_printk(APIC_VERBOSE, "..... host bus clock speed is "
- "%ld.%04ld MHz.\n",
- result/(1000000/HZ),
- result%(1000000/HZ));
+ apic_pm_activate();

- return result;
-}
+ return 0;

-static unsigned int calibration_result;
+no_apic:
+ printk(KERN_INFO "No local APIC present or hardware disabled\n");
+ return -1;
+}

-void __init setup_boot_APIC_clock(void)
+/**
+ * init_apic_mappings - initialize APIC mappings
+ */
+void __init init_apic_mappings(void)
{
- unsigned long flags;
- apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n");
- using_apic_timer = 1;
-
- local_irq_save(flags);
+ unsigned long apic_phys;

- calibration_result = calibrate_APIC_clock();
/*
- * Now set up the timer for real.
+ * If no local APIC can be found then set up a fake all
+ * zeroes page to simulate the local APIC and another
+ * one for the IO-APIC.
*/
- setup_APIC_timer(calibration_result);
+ if (!smp_found_config && detect_init_APIC()) {
+ apic_phys = (unsigned long) alloc_bootmem_pages(PAGE_SIZE);
+ apic_phys = __pa(apic_phys);
+ } else
+ apic_phys = mp_lapic_addr;

- local_irq_restore(flags);
-}
+ set_fixmap_nocache(FIX_APIC_BASE, apic_phys);
+ printk(KERN_DEBUG "mapped APIC to %08lx (%08lx)\n", APIC_BASE,
+ apic_phys);

-void __devinit setup_secondary_APIC_clock(void)
-{
- setup_APIC_timer(calibration_result);
-}
+ /*
+ * Fetch the APIC ID of the BSP in case we have a
+ * default configuration (or the MP table is broken).
+ */
+ if (boot_cpu_physical_apicid == -1U)
+ boot_cpu_physical_apicid = GET_APIC_ID(apic_read(APIC_ID));

-void disable_APIC_timer(void)
-{
- if (using_apic_timer) {
- unsigned long v;
+#ifdef CONFIG_X86_IO_APIC
+ {
+ unsigned long ioapic_phys, idx = FIX_IO_APIC_BASE_0;
+ int i;

- v = apic_read(APIC_LVTT);
- /*
- * When an illegal vector value (0-15) is written to an LVT
- * entry and delivery mode is Fixed, the APIC may signal an
- * illegal vector error, with out regard to whether the mask
- * bit is set or whether an interrupt is actually seen on input.
- *
- * Boot sequence might call this function when the LVTT has
- * '0' vector value. So make sure vector field is set to
- * valid value.
- */
- v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
- apic_write_around(APIC_LVTT, v);
+ for (i = 0; i < nr_ioapics; i++) {
+ if (smp_found_config) {
+ ioapic_phys = mp_ioapics[i].mpc_apicaddr;
+ if (!ioapic_phys) {
+ printk(KERN_ERR
+ "WARNING: bogus zero IO-APIC "
+ "address found in MPTABLE, "
+ "disabling IO/APIC support!\n");
+ smp_found_config = 0;
+ skip_ioapic_setup = 1;
+ goto fake_ioapic_page;
+ }
+ } else {
+fake_ioapic_page:
+ ioapic_phys = (unsigned long)
+ alloc_bootmem_pages(PAGE_SIZE);
+ ioapic_phys = __pa(ioapic_phys);
+ }
+ set_fixmap_nocache(idx, ioapic_phys);
+ printk(KERN_DEBUG "mapped IOAPIC to %08lx (%08lx)\n",
+ __fix_to_virt(idx), ioapic_phys);
+ idx++;
+ }
}
+#endif
}

-void enable_APIC_timer(void)
+/*
+ * This initializes the IO-APIC and APIC hardware if this is
+ * a UP kernel.
+ */
+int __init APIC_init_uniprocessor (void)
{
- int cpu = smp_processor_id();
-
- if (using_apic_timer &&
- !cpu_isset(cpu, timer_bcast_ipi)) {
- unsigned long v;
-
- v = apic_read(APIC_LVTT);
- apic_write_around(APIC_LVTT, v & ~APIC_LVT_MASKED);
- }
-}
+ if (enable_local_apic < 0)
+ clear_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);

-void switch_APIC_timer_to_ipi(void *cpumask)
-{
- cpumask_t mask = *(cpumask_t *)cpumask;
- int cpu = smp_processor_id();
+ if (!smp_found_config && !cpu_has_apic)
+ return -1;

- if (cpu_isset(cpu, mask) &&
- !cpu_isset(cpu, timer_bcast_ipi)) {
- disable_APIC_timer();
- cpu_set(cpu, timer_bcast_ipi);
+ /*
+ * Complain if the BIOS pretends there is one.
+ */
+ if (!cpu_has_apic &&
+ APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid])) {
+ printk(KERN_ERR "BIOS bug, local APIC #%d not detected!...\n",
+ boot_cpu_physical_apicid);
+ clear_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);
+ return -1;
}
-}
-EXPORT_SYMBOL(switch_APIC_timer_to_ipi);

-void switch_ipi_to_APIC_timer(void *cpumask)
-{
- cpumask_t mask = *(cpumask_t *)cpumask;
- int cpu = smp_processor_id();
+ verify_local_APIC();

- if (cpu_isset(cpu, mask) &&
- cpu_isset(cpu, timer_bcast_ipi)) {
- cpu_clear(cpu, timer_bcast_ipi);
- enable_APIC_timer();
- }
-}
-EXPORT_SYMBOL(switch_ipi_to_APIC_timer);
+ connect_bsp_APIC();

-#undef APIC_DIVISOR
+ /*
+ * Hack: In case of kdump, after a crash, kernel might be booting
+ * on a cpu with non-zero lapic id. But boot_cpu_physical_apicid
+ * might be zero if read from MP tables. Get it from LAPIC.
+ */
+#ifdef CONFIG_CRASH_DUMP
+ boot_cpu_physical_apicid = GET_APIC_ID(apic_read(APIC_ID));
+#endif
+ phys_cpu_present_map = physid_mask_of_physid(boot_cpu_physical_apicid);

-/*
- * Local timer interrupt handler. It does both profiling and
- * process statistics/rescheduling.
- *
- * We do profiling in every local tick, statistics/rescheduling
- * happen only every 'profiling multiplier' ticks. The default
- * multiplier is 1 and it can be changed by writing the new multiplier
- * value into /proc/profile.
- */
+ setup_local_APIC();

-inline void smp_local_timer_interrupt(void)
-{
- profile_tick(CPU_PROFILING);
-#ifdef CONFIG_SMP
- update_process_times(user_mode_vm(get_irq_regs()));
+#ifdef CONFIG_X86_IO_APIC
+ if (smp_found_config)
+ if (!skip_ioapic_setup && nr_ioapics)
+ setup_IO_APIC();
#endif
+ setup_boot_APIC_clock();

- /*
- * We take the 'long' return path, and there every subsystem
- * grabs the apropriate locks (kernel lock/ irq lock).
- *
- * we might want to decouple profiling from the 'long path',
- * and do the profiling totally in assembly.
- *
- * Currently this isn't too much of an issue (performance wise),
- * we can take more than 100K local irqs per second on a 100 MHz P5.
- */
+ return 0;
}

/*
- * Local APIC timer interrupt. This is the most natural way for doing
- * local interrupts, but local timer interrupts can be emulated by
- * broadcast interrupts too. [in case the hw doesn't support APIC timers]
- *
- * [ if a single-CPU system runs an SMP kernel then we call the local
- * interrupt as well. Thus we cannot inline the local irq ... ]
+ * APIC command line parameters
*/
-
-fastcall void smp_apic_timer_interrupt(struct pt_regs *regs)
+static int __init parse_lapic(char *arg)
{
- struct pt_regs *old_regs = set_irq_regs(regs);
- int cpu = smp_processor_id();
-
- /*
- * the NMI deadlock-detector uses this.
- */
- per_cpu(irq_stat, cpu).apic_timer_irqs++;
-
- /*
- * NOTE! We'd better ACK the irq immediately,
- * because timer handling can be slow.
- */
- ack_APIC_irq();
- /*
- * update_process_times() expects us to have done irq_enter().
- * Besides, if we don't timer interrupts ignore the global
- * interrupt lock, which is the WrongThing (tm) to do.
- */
- irq_enter();
- smp_local_timer_interrupt();
- irq_exit();
- set_irq_regs(old_regs);
+ enable_local_apic = 1;
+ return 0;
}
+early_param("lapic", parse_lapic);

-#ifndef CONFIG_SMP
-static void up_apic_timer_interrupt_call(void)
+static int __init parse_nolapic(char *arg)
{
- int cpu = smp_processor_id();
-
- /*
- * the NMI deadlock-detector uses this.
- */
- per_cpu(irq_stat, cpu).apic_timer_irqs++;
-
- smp_local_timer_interrupt();
+ enable_local_apic = -1;
+ clear_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);
+ return 0;
}
-#endif
+early_param("nolapic", parse_nolapic);

-void smp_send_timer_broadcast_ipi(void)
+static int __init apic_set_verbosity(char *str)
{
- cpumask_t mask;
-
- cpus_and(mask, cpu_online_map, timer_bcast_ipi);
- if (!cpus_empty(mask)) {
-#ifdef CONFIG_SMP
- send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
-#else
- /*
- * We can directly call the apic timer interrupt handler
- * in UP case. Minus all irq related functions
- */
- up_apic_timer_interrupt_call();
-#endif
- }
+ if (strcmp("debug", str) == 0)
+ apic_verbosity = APIC_DEBUG;
+ else if (strcmp("verbose", str) == 0)
+ apic_verbosity = APIC_VERBOSE;
+ return 1;
}

-int setup_profiling_timer(unsigned int multiplier)
-{
- return -EINVAL;
-}
+__setup("apic=", apic_set_verbosity);
+
+
+/*
+ * Local APIC interrupts
+ */

/*
* This interrupt should _never_ happen with our APIC/SMP architecture
@@ -1316,15 +1160,14 @@ fastcall void smp_spurious_interrupt(str
ack_APIC_irq();

/* see sw-dev-man vol 3, chapter 7.4.13.5 */
- printk(KERN_INFO "spurious APIC interrupt on CPU#%d, should never happen.\n",
- smp_processor_id());
+ printk(KERN_INFO "spurious APIC interrupt on CPU#%d, "
+ "should never happen.\n", smp_processor_id());
irq_exit();
}

/*
* This interrupt should never happen with our APIC/SMP architecture
*/
-
fastcall void smp_error_interrupt(struct pt_regs *regs)
{
unsigned long v, v1;
@@ -1348,69 +1191,261 @@ fastcall void smp_error_interrupt(struct
7: Illegal register address
*/
printk (KERN_DEBUG "APIC error on CPU%d: %02lx(%02lx)\n",
- smp_processor_id(), v , v1);
+ smp_processor_id(), v , v1);
irq_exit();
}

/*
- * This initializes the IO-APIC and APIC hardware if this is
- * a UP kernel.
+ * Initialize APIC interrupts
*/
-int __init APIC_init_uniprocessor (void)
+void __init apic_intr_init(void)
{
- if (enable_local_apic < 0)
- clear_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);
+#ifdef CONFIG_SMP
+ smp_intr_init();
+#endif
+ /* self generated IPI for local APIC timer */
+ set_intr_gate(LOCAL_TIMER_VECTOR, apic_timer_interrupt);

- if (!smp_found_config && !cpu_has_apic)
- return -1;
+ /* IPI vectors for APIC spurious and error interrupts */
+ set_intr_gate(SPURIOUS_APIC_VECTOR, spurious_interrupt);
+ set_intr_gate(ERROR_APIC_VECTOR, error_interrupt);

- /*
- * Complain if the BIOS pretends there is one.
- */
- if (!cpu_has_apic && APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid])) {
- printk(KERN_ERR "BIOS bug, local APIC #%d not detected!...\n",
- boot_cpu_physical_apicid);
- clear_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);
- return -1;
+ /* thermal monitor LVT interrupt */
+#ifdef CONFIG_X86_MCE_P4THERMAL
+ set_intr_gate(THERMAL_APIC_VECTOR, thermal_interrupt);
+#endif
+}
+
+/**
+ * connect_bsp_APIC - attach the APIC to the interrupt system
+ */
+void __init connect_bsp_APIC(void)
+{
+ if (pic_mode) {
+ /*
+ * Do not trust the local APIC being empty at bootup.
+ */
+ clear_local_APIC();
+ /*
+ * PIC mode, enable APIC mode in the IMCR, i.e. connect BSP's
+ * local APIC to INT and NMI lines.
+ */
+ apic_printk(APIC_VERBOSE, "leaving PIC mode, "
+ "enabling APIC mode.\n");
+ outb(0x70, 0x22);
+ outb(0x01, 0x23);
}
+ enable_apic_mode();
+}

- verify_local_APIC();
+/**
+ * disconnect_bsp_APIC - detach the APIC from the interrupt system
+ * @virt_wire_setup: indicates, whether virtual wire mode is selected
+ *
+ * Virtual wire mode is necessary to deliver legacy interrupts even when the
+ * APIC is disabled.
+ */
+void disconnect_bsp_APIC(int virt_wire_setup)
+{
+ if (pic_mode) {
+ /*
+ * Put the board back into PIC mode (has an effect only on
+ * certain older boards). Note that APIC interrupts, including
+ * IPIs, won't work beyond this point! The only exception are
+ * INIT IPIs.
+ */
+ apic_printk(APIC_VERBOSE, "disabling APIC mode, "
+ "entering PIC mode.\n");
+ outb(0x70, 0x22);
+ outb(0x00, 0x23);
+ } else {
+ /* Go back to Virtual Wire compatibility mode */
+ unsigned long value;

- connect_bsp_APIC();
+ /* For the spurious interrupt use vector F, and enable it */
+ value = apic_read(APIC_SPIV);
+ value &= ~APIC_VECTOR_MASK;
+ value |= APIC_SPIV_APIC_ENABLED;
+ value |= 0xf;
+ apic_write_around(APIC_SPIV, value);

- /*
- * Hack: In case of kdump, after a crash, kernel might be booting
- * on a cpu with non-zero lapic id. But boot_cpu_physical_apicid
- * might be zero if read from MP tables. Get it from LAPIC.
- */
-#ifdef CONFIG_CRASH_DUMP
- boot_cpu_physical_apicid = GET_APIC_ID(apic_read(APIC_ID));
-#endif
- phys_cpu_present_map = physid_mask_of_physid(boot_cpu_physical_apicid);
+ if (!virt_wire_setup) {
+ /*
+ * For LVT0 make it edge triggered, active high,
+ * external and enabled
+ */
+ value = apic_read(APIC_LVT0);
+ value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
+ APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
+ APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED );
+ value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
+ value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_EXTINT);
+ apic_write_around(APIC_LVT0, value);
+ } else {
+ /* Disable LVT0 */
+ apic_write_around(APIC_LVT0, APIC_LVT_MASKED);
+ }

- setup_local_APIC();
+ /*
+ * For LVT1 make it edge triggered, active high, nmi and
+ * enabled
+ */
+ value = apic_read(APIC_LVT1);
+ value &= ~(
+ APIC_MODE_MASK | APIC_SEND_PENDING |
+ APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
+ APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
+ value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
+ value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_NMI);
+ apic_write_around(APIC_LVT1, value);
+ }
+}

-#ifdef CONFIG_X86_IO_APIC
- if (smp_found_config)
- if (!skip_ioapic_setup && nr_ioapics)
- setup_IO_APIC();
+/*
+ * Power management
+ */
+#ifdef CONFIG_PM
+
+static struct {
+ int active;
+ /* r/w apic fields */
+ unsigned int apic_id;
+ unsigned int apic_taskpri;
+ unsigned int apic_ldr;
+ unsigned int apic_dfr;
+ unsigned int apic_spiv;
+ unsigned int apic_lvtt;
+ unsigned int apic_lvtpc;
+ unsigned int apic_lvt0;
+ unsigned int apic_lvt1;
+ unsigned int apic_lvterr;
+ unsigned int apic_tmict;
+ unsigned int apic_tdcr;
+ unsigned int apic_thmr;
+} apic_pm_state;
+
+static int lapic_suspend(struct sys_device *dev, pm_message_t state)
+{
+ unsigned long flags;
+ int maxlvt;
+
+ if (!apic_pm_state.active)
+ return 0;
+
+ maxlvt = get_maxlvt();
+
+ apic_pm_state.apic_id = apic_read(APIC_ID);
+ apic_pm_state.apic_taskpri = apic_read(APIC_TASKPRI);
+ apic_pm_state.apic_ldr = apic_read(APIC_LDR);
+ apic_pm_state.apic_dfr = apic_read(APIC_DFR);
+ apic_pm_state.apic_spiv = apic_read(APIC_SPIV);
+ apic_pm_state.apic_lvtt = apic_read(APIC_LVTT);
+ if (maxlvt >= 4)
+ apic_pm_state.apic_lvtpc = apic_read(APIC_LVTPC);
+ apic_pm_state.apic_lvt0 = apic_read(APIC_LVT0);
+ apic_pm_state.apic_lvt1 = apic_read(APIC_LVT1);
+ apic_pm_state.apic_lvterr = apic_read(APIC_LVTERR);
+ apic_pm_state.apic_tmict = apic_read(APIC_TMICT);
+ apic_pm_state.apic_tdcr = apic_read(APIC_TDCR);
+#ifdef CONFIG_X86_MCE_P4THERMAL
+ if (maxlvt >= 5)
+ apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
#endif
- setup_boot_APIC_clock();

+ local_irq_save(flags);
+ disable_local_APIC();
+ local_irq_restore(flags);
return 0;
}

-static int __init parse_lapic(char *arg)
+static int lapic_resume(struct sys_device *dev)
{
- lapic_enable();
+ unsigned int l, h;
+ unsigned long flags;
+ int maxlvt;
+
+ if (!apic_pm_state.active)
+ return 0;
+
+ maxlvt = get_maxlvt();
+
+ local_irq_save(flags);
+
+ /*
+ * Make sure the APICBASE points to the right address
+ *
+ * FIXME! This will be wrong if we ever support suspend on
+ * SMP! We'll need to do this as part of the CPU restore!
+ */
+ rdmsr(MSR_IA32_APICBASE, l, h);
+ l &= ~MSR_IA32_APICBASE_BASE;
+ l |= MSR_IA32_APICBASE_ENABLE | mp_lapic_addr;
+ wrmsr(MSR_IA32_APICBASE, l, h);
+
+ apic_write(APIC_LVTERR, ERROR_APIC_VECTOR | APIC_LVT_MASKED);
+ apic_write(APIC_ID, apic_pm_state.apic_id);
+ apic_write(APIC_DFR, apic_pm_state.apic_dfr);
+ apic_write(APIC_LDR, apic_pm_state.apic_ldr);
+ apic_write(APIC_TASKPRI, apic_pm_state.apic_taskpri);
+ apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
+ apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
+ apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
+#ifdef CONFIG_X86_MCE_P4THERMAL
+ if (maxlvt >= 5)
+ apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
+#endif
+ if (maxlvt >= 4)
+ apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
+ apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
+ apic_write(APIC_TDCR, apic_pm_state.apic_tdcr);
+ apic_write(APIC_TMICT, apic_pm_state.apic_tmict);
+ apic_write(APIC_ESR, 0);
+ apic_read(APIC_ESR);
+ apic_write(APIC_LVTERR, apic_pm_state.apic_lvterr);
+ apic_write(APIC_ESR, 0);
+ apic_read(APIC_ESR);
+ local_irq_restore(flags);
return 0;
}
-early_param("lapic", parse_lapic);

-static int __init parse_nolapic(char *arg)
+/*
+ * This device has no shutdown method - fully functioning local APICs
+ * are needed on every CPU up until machine_halt/restart/poweroff.
+ */
+
+static struct sysdev_class lapic_sysclass = {
+ set_kset_name("lapic"),
+ .resume = lapic_resume,
+ .suspend = lapic_suspend,
+};
+
+static struct sys_device device_lapic = {
+ .id = 0,
+ .cls = &lapic_sysclass,
+};
+
+static void __devinit apic_pm_activate(void)
{
- lapic_disable();
- return 0;
+ apic_pm_state.active = 1;
}
-early_param("nolapic", parse_nolapic);

+static int __init init_lapic_sysfs(void)
+{
+ int error;
+
+ if (!cpu_has_apic)
+ return 0;
+ /* XXX: remove suspend/resume procs if !apic_pm_state.active? */
+
+ error = sysdev_class_register(&lapic_sysclass);
+ if (!error)
+ error = sysdev_register(&device_lapic);
+ return error;
+}
+device_initcall(init_lapic_sysfs);
+
+#else /* CONFIG_PM */
+
+static void apic_pm_activate(void) { }
+
+#endif /* CONFIG_PM */
Index: linux/arch/i386/kernel/io_apic.c
===================================================================
--- linux.orig/arch/i386/kernel/io_apic.c
+++ linux/arch/i386/kernel/io_apic.c
@@ -1592,7 +1592,7 @@ void /*__init*/ print_local_APIC(void *
v = apic_read(APIC_LVR);
printk(KERN_INFO "... APIC VERSION: %08x\n", v);
ver = GET_APIC_VERSION(v);
- maxlvt = get_maxlvt();
+ maxlvt = lapic_get_maxlvt();

v = apic_read(APIC_TASKPRI);
printk(KERN_DEBUG "... APIC TASKPRI: %08x (%02x)\n", v, v & APIC_TPRI_MASK);
Index: linux/arch/i386/kernel/irq.c
===================================================================
--- linux.orig/arch/i386/kernel/irq.c
+++ linux/arch/i386/kernel/irq.c
@@ -10,7 +10,6 @@
* io_apic.c.)
*/

-#include <asm/uaccess.h>
#include <linux/module.h>
#include <linux/seq_file.h>
#include <linux/interrupt.h>
@@ -19,19 +18,34 @@
#include <linux/cpu.h>
#include <linux/delay.h>

+#include <asm/apic.h>
+#include <asm/uaccess.h>
+
DEFINE_PER_CPU(irq_cpustat_t, irq_stat) ____cacheline_internodealigned_in_smp;
EXPORT_PER_CPU_SYMBOL(irq_stat);

-#ifndef CONFIG_X86_LOCAL_APIC
/*
* 'what should we do if we get a hw irq event on an illegal vector'.
* each architecture has to answer this themselves.
*/
void ack_bad_irq(unsigned int irq)
{
- printk("unexpected IRQ trap at vector %02x\n", irq);
-}
+ printk(KERN_ERR "unexpected IRQ trap at vector %02x\n", irq);
+
+#ifdef CONFIG_X86_LOCAL_APIC
+ /*
+ * Currently unexpected vectors happen only on SMP and APIC.
+ * We _must_ ack these because every local APIC has only N
+ * irq slots per priority level, and a 'hanging, unacked' IRQ
+ * holds up an irq slot - in excessive cases (when multiple
+ * unexpected vectors occur) that might lock up the APIC
+ * completely.
+ * But only ack when the APIC is enabled -AK
+ */
+ if (cpu_has_apic)
+ ack_APIC_irq();
#endif
+}

#ifdef CONFIG_4KSTACKS
/*
Index: linux/arch/i386/kernel/smpboot.c
===================================================================
--- linux.orig/arch/i386/kernel/smpboot.c
+++ linux/arch/i386/kernel/smpboot.c
@@ -735,7 +735,7 @@ wakeup_secondary_cpu(int logical_apicid,
/*
* Due to the Pentium erratum 3AP.
*/
- maxlvt = get_maxlvt();
+ maxlvt = lapic_get_maxlvt();
if (maxlvt > 3) {
apic_read_around(APIC_SPIV);
apic_write(APIC_ESR, 0);
@@ -825,7 +825,7 @@ wakeup_secondary_cpu(int phys_apicid, un
*/
Dprintk("#startup loops: %d.\n", num_starts);

- maxlvt = get_maxlvt();
+ maxlvt = lapic_get_maxlvt();

for (j = 1; j <= num_starts; j++) {
Dprintk("Sending STARTUP #%d.\n",j);
Index: linux/include/asm-i386/apic.h
===================================================================
--- linux.orig/include/asm-i386/apic.h
+++ linux/include/asm-i386/apic.h
@@ -86,7 +86,7 @@ static inline void ack_APIC_irq(void)

extern void (*wait_timer_tick)(void);

-extern int get_maxlvt(void);
+extern int lapic_get_maxlvt(void);
extern void clear_local_APIC(void);
extern void connect_bsp_APIC (void);
extern void disconnect_bsp_APIC (int virt_wire_setup);

2006-11-18 14:48:35

by Ingo Molnar

[permalink] [raw]
Subject: Re: [PATCH] Regard MSRs in lapic_suspend()/lapic_resume()


* Ingo Molnar <[email protected]> wrote:

> Andrew, find below updated-i386-cleanup-apic-code.patch updated to
> come after Karsten's patch.

forgot about the get_maxlvt() => lapic_get_maxlvt() rename - the updated
updated-i386-cleanup-apic-code.patch below does that correctly too.

Ingo

----------->
From: Thomas Gleixner <[email protected]>

The apic code is quite unstructured and missing a lot of comments.

- Restructure the code into helper functions, timer, setup/shutdown,
interrupt and power management blocks.
- Fixup comments.
- Namespace fixups
- Inline helpers for version and is_integrated
- Combine the ack_bad_irq functions

No functional changes.

Signed-off-by: Thomas Gleixner <[email protected]>
Signed-off-by: Ingo Molnar <[email protected]>
Cc: Zachary Amsden <[email protected]>
Cc: "Eric W. Biederman" <[email protected]>
Cc: Rohit Seth <[email protected]>
Cc: Andi Kleen <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
---
arch/i386/kernel/apic.c | 2075 ++++++++++++++++++++++-----------------------
arch/i386/kernel/io_apic.c | 2
arch/i386/kernel/irq.c | 22
arch/i386/kernel/smpboot.c | 4
include/asm-i386/apic.h | 2
5 files changed, 1077 insertions(+), 1028 deletions(-)

Index: linux/arch/i386/kernel/apic.c
===================================================================
--- linux.orig/arch/i386/kernel/apic.c
+++ linux/arch/i386/kernel/apic.c
@@ -44,6 +44,13 @@
#include "io_ports.h"

/*
+ * Sanity check
+ */
+#if (SPURIOUS_APIC_VECTOR & 0x0F) != 0x0F
+# error SPURIOUS_APIC_VECTOR definition error
+#endif
+
+/*
* cpu_mask that denotes the CPUs that needs timer interrupt coming in as
* IPIs in place of local APIC timers
*/
@@ -51,561 +58,559 @@ static cpumask_t timer_bcast_ipi;

/*
* Knob to control our willingness to enable the local APIC.
+ *
+ * -1=force-disable, +1=force-enable
*/
-static int enable_local_apic __initdata = 0; /* -1=force-disable, +1=force-enable */
-
-static inline void lapic_disable(void)
-{
- enable_local_apic = -1;
- clear_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);
-}
-
-static inline void lapic_enable(void)
-{
- enable_local_apic = 1;
-}
+static int enable_local_apic __initdata = 0;

/*
- * Debug level
+ * Debug level, exported for io_apic.c
*/
int apic_verbosity;

-
static void apic_pm_activate(void);

-static int modern_apic(void)
+
+/* Using APIC to generate smp_local_timer_interrupt? */
+int using_apic_timer __read_mostly = 0;
+
+/* Local APIC was disabled by the BIOS and enabled by the kernel */
+static int enabled_via_apicbase;
+
+/*
+ * Get the LAPIC version
+ */
+static inline int lapic_get_version(void)
{
- unsigned int lvr, version;
- /* AMD systems use old APIC versions, so check the CPU */
- if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
- boot_cpu_data.x86 >= 0xf)
- return 1;
- lvr = apic_read(APIC_LVR);
- version = GET_APIC_VERSION(lvr);
- return version >= 0x14;
+ return GET_APIC_VERSION(apic_read(APIC_LVR));
}

/*
- * 'what should we do if we get a hw irq event on an illegal vector'.
- * each architecture has to answer this themselves.
+ * Check, if the APIC is integrated or a seperate chip
*/
-void ack_bad_irq(unsigned int irq)
+static inline int lapic_is_integrated(void)
{
- printk("unexpected IRQ trap at vector %02x\n", irq);
- /*
- * Currently unexpected vectors happen only on SMP and APIC.
- * We _must_ ack these because every local APIC has only N
- * irq slots per priority level, and a 'hanging, unacked' IRQ
- * holds up an irq slot - in excessive cases (when multiple
- * unexpected vectors occur) that might lock up the APIC
- * completely.
- * But only ack when the APIC is enabled -AK
- */
- if (cpu_has_apic)
- ack_APIC_irq();
+ return APIC_INTEGRATED(lapic_get_version());
}

-void __init apic_intr_init(void)
+/*
+ * Check, whether this is a modern or a first generation APIC
+ */
+static int modern_apic(void)
{
-#ifdef CONFIG_SMP
- smp_intr_init();
-#endif
- /* self generated IPI for local APIC timer */
- set_intr_gate(LOCAL_TIMER_VECTOR, apic_timer_interrupt);
-
- /* IPI vectors for APIC spurious and error interrupts */
- set_intr_gate(SPURIOUS_APIC_VECTOR, spurious_interrupt);
- set_intr_gate(ERROR_APIC_VECTOR, error_interrupt);
-
- /* thermal monitor LVT interrupt */
-#ifdef CONFIG_X86_MCE_P4THERMAL
- set_intr_gate(THERMAL_APIC_VECTOR, thermal_interrupt);
-#endif
+ /* AMD systems use old APIC versions, so check the CPU */
+ if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
+ boot_cpu_data.x86 >= 0xf)
+ return 1;
+ return lapic_get_version() >= 0x14;
}

-/* Using APIC to generate smp_local_timer_interrupt? */
-int using_apic_timer __read_mostly = 0;
-
-static int enabled_via_apicbase;
-
+/**
+ * enable_NMI_through_LVT0 - enable NMI through local vector table 0
+ */
void enable_NMI_through_LVT0 (void * dummy)
{
- unsigned int v, ver;
+ unsigned int v = APIC_DM_NMI;

- ver = apic_read(APIC_LVR);
- ver = GET_APIC_VERSION(ver);
- v = APIC_DM_NMI; /* unmask and set to NMI */
- if (!APIC_INTEGRATED(ver)) /* 82489DX */
+ /* Level triggered for 82489DX */
+ if (!lapic_is_integrated())
v |= APIC_LVT_LEVEL_TRIGGER;
apic_write_around(APIC_LVT0, v);
}

+/**
+ * get_physical_broadcast - Get number of physical broadcast IDs
+ */
int get_physical_broadcast(void)
{
- if (modern_apic())
- return 0xff;
- else
- return 0xf;
+ return modern_apic() ? 0xff : 0xf;
}

-int get_maxlvt(void)
+/**
+ * lapic_get_maxlvt - get the maximum number of local vector table entries
+ */
+int lapic_get_maxlvt(void)
{
- unsigned int v, ver, maxlvt;
+ unsigned int v = apic_read(APIC_LVR);

- v = apic_read(APIC_LVR);
- ver = GET_APIC_VERSION(v);
/* 82489DXs do not report # of LVT entries. */
- maxlvt = APIC_INTEGRATED(ver) ? GET_APIC_MAXLVT(v) : 2;
- return maxlvt;
+ return APIC_INTEGRATED(GET_APIC_VERSION(v)) ? GET_APIC_MAXLVT(v) : 2;
}

-void clear_local_APIC(void)
+/*
+ * Local APIC timer
+ */
+
+/*
+ * This part sets up the APIC 32 bit clock in LVTT1, with HZ interrupts
+ * per second. We assume that the caller has already set up the local
+ * APIC.
+ *
+ * The APIC timer is not exactly sync with the external timer chip, it
+ * closely follows bus clocks.
+ */
+
+/*
+ * The timer chip is already set up at HZ interrupts per second here,
+ * but we do not accept timer interrupts yet. We only allow the BP
+ * to calibrate.
+ */
+static unsigned int __devinit get_8254_timer_count(void)
{
- int maxlvt;
- unsigned long v;
+ unsigned long flags;

- maxlvt = get_maxlvt();
+ unsigned int count;

- /*
- * Masking an LVT entry can trigger a local APIC error
- * if the vector is zero. Mask LVTERR first to prevent this.
- */
- if (maxlvt >= 3) {
- v = ERROR_APIC_VECTOR; /* any non-zero vector will do */
- apic_write_around(APIC_LVTERR, v | APIC_LVT_MASKED);
- }
- /*
- * Careful: we have to set masks only first to deassert
- * any level-triggered sources.
- */
- v = apic_read(APIC_LVTT);
- apic_write_around(APIC_LVTT, v | APIC_LVT_MASKED);
- v = apic_read(APIC_LVT0);
- apic_write_around(APIC_LVT0, v | APIC_LVT_MASKED);
- v = apic_read(APIC_LVT1);
- apic_write_around(APIC_LVT1, v | APIC_LVT_MASKED);
- if (maxlvt >= 4) {
- v = apic_read(APIC_LVTPC);
- apic_write_around(APIC_LVTPC, v | APIC_LVT_MASKED);
- }
+ spin_lock_irqsave(&i8253_lock, flags);

-/* lets not touch this if we didn't frob it */
-#ifdef CONFIG_X86_MCE_P4THERMAL
- if (maxlvt >= 5) {
- v = apic_read(APIC_LVTTHMR);
- apic_write_around(APIC_LVTTHMR, v | APIC_LVT_MASKED);
- }
-#endif
- /*
- * Clean APIC state for other OSs:
- */
- apic_write_around(APIC_LVTT, APIC_LVT_MASKED);
- apic_write_around(APIC_LVT0, APIC_LVT_MASKED);
- apic_write_around(APIC_LVT1, APIC_LVT_MASKED);
- if (maxlvt >= 3)
- apic_write_around(APIC_LVTERR, APIC_LVT_MASKED);
- if (maxlvt >= 4)
- apic_write_around(APIC_LVTPC, APIC_LVT_MASKED);
+ outb_p(0x00, PIT_MODE);
+ count = inb_p(PIT_CH0);
+ count |= inb_p(PIT_CH0) << 8;

-#ifdef CONFIG_X86_MCE_P4THERMAL
- if (maxlvt >= 5)
- apic_write_around(APIC_LVTTHMR, APIC_LVT_MASKED);
-#endif
- v = GET_APIC_VERSION(apic_read(APIC_LVR));
- if (APIC_INTEGRATED(v)) { /* !82489DX */
- if (maxlvt > 3) /* Due to Pentium errata 3AP and 11AP. */
- apic_write(APIC_ESR, 0);
- apic_read(APIC_ESR);
- }
-}
+ spin_unlock_irqrestore(&i8253_lock, flags);

-void __init connect_bsp_APIC(void)
-{
- if (pic_mode) {
- /*
- * Do not trust the local APIC being empty at bootup.
- */
- clear_local_APIC();
- /*
- * PIC mode, enable APIC mode in the IMCR, i.e.
- * connect BSP's local APIC to INT and NMI lines.
- */
- apic_printk(APIC_VERBOSE, "leaving PIC mode, "
- "enabling APIC mode.\n");
- outb(0x70, 0x22);
- outb(0x01, 0x23);
- }
- enable_apic_mode();
+ return count;
}

-void disconnect_bsp_APIC(int virt_wire_setup)
+/* next tick in 8254 can be caught by catching timer wraparound */
+static void __devinit wait_8254_wraparound(void)
{
- if (pic_mode) {
- /*
- * Put the board back into PIC mode (has an effect
- * only on certain older boards). Note that APIC
- * interrupts, including IPIs, won't work beyond
- * this point! The only exception are INIT IPIs.
- */
- apic_printk(APIC_VERBOSE, "disabling APIC mode, "
- "entering PIC mode.\n");
- outb(0x70, 0x22);
- outb(0x00, 0x23);
- }
- else {
- /* Go back to Virtual Wire compatibility mode */
- unsigned long value;
+ unsigned int curr_count, prev_count;

- /* For the spurious interrupt use vector F, and enable it */
- value = apic_read(APIC_SPIV);
- value &= ~APIC_VECTOR_MASK;
- value |= APIC_SPIV_APIC_ENABLED;
- value |= 0xf;
- apic_write_around(APIC_SPIV, value);
+ curr_count = get_8254_timer_count();
+ do {
+ prev_count = curr_count;
+ curr_count = get_8254_timer_count();

- if (!virt_wire_setup) {
- /* For LVT0 make it edge triggered, active high, external and enabled */
- value = apic_read(APIC_LVT0);
- value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
- APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
- APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED );
- value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
- value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_EXTINT);
- apic_write_around(APIC_LVT0, value);
- }
- else {
- /* Disable LVT0 */
- apic_write_around(APIC_LVT0, APIC_LVT_MASKED);
- }
+ /* workaround for broken Mercury/Neptune */
+ if (prev_count >= curr_count + 0x100)
+ curr_count = get_8254_timer_count();

- /* For LVT1 make it edge triggered, active high, nmi and enabled */
- value = apic_read(APIC_LVT1);
- value &= ~(
- APIC_MODE_MASK | APIC_SEND_PENDING |
- APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
- APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
- value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
- value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_NMI);
- apic_write_around(APIC_LVT1, value);
- }
+ } while (prev_count >= curr_count);
}

-void disable_local_APIC(void)
+/*
+ * Default initialization for 8254 timers. If we use other timers like HPET,
+ * we override this later
+ */
+void (*wait_timer_tick)(void) __devinitdata = wait_8254_wraparound;
+
+/*
+ * This function sets up the local APIC timer, with a timeout of
+ * 'clocks' APIC bus clock. During calibration we actually call
+ * this function twice on the boot CPU, once with a bogus timeout
+ * value, second time for real. The other (noncalibrating) CPUs
+ * call this function only once, with the real, calibrated value.
+ *
+ * We do reads before writes even if unnecessary, to get around the
+ * P5 APIC double write bug.
+ */
+
+#define APIC_DIVISOR 16
+
+static void __setup_APIC_LVTT(unsigned int clocks)
{
- unsigned long value;
+ unsigned int lvtt_value, tmp_value;
+ int cpu = smp_processor_id();

- clear_local_APIC();
+ lvtt_value = APIC_LVT_TIMER_PERIODIC | LOCAL_TIMER_VECTOR;
+ if (!lapic_is_integrated())
+ lvtt_value |= SET_APIC_TIMER_BASE(APIC_TIMER_BASE_DIV);
+
+ if (cpu_isset(cpu, timer_bcast_ipi))
+ lvtt_value |= APIC_LVT_MASKED;
+
+ apic_write_around(APIC_LVTT, lvtt_value);

/*
- * Disable APIC (implies clearing of registers
- * for 82489DX!).
+ * Divide PICLK by 16
*/
- value = apic_read(APIC_SPIV);
- value &= ~APIC_SPIV_APIC_ENABLED;
- apic_write_around(APIC_SPIV, value);
+ tmp_value = apic_read(APIC_TDCR);
+ apic_write_around(APIC_TDCR, (tmp_value
+ & ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE))
+ | APIC_TDR_DIV_16);

- if (enabled_via_apicbase) {
- unsigned int l, h;
- rdmsr(MSR_IA32_APICBASE, l, h);
- l &= ~MSR_IA32_APICBASE_ENABLE;
- wrmsr(MSR_IA32_APICBASE, l, h);
- }
+ apic_write_around(APIC_TMICT, clocks/APIC_DIVISOR);
}

-/*
- * This is to verify that we're looking at a real local APIC.
- * Check these against your board if the CPUs aren't getting
- * started for no apparent reason.
- */
-int __init verify_local_APIC(void)
+static void __devinit setup_APIC_timer(unsigned int clocks)
{
- unsigned int reg0, reg1;
+ unsigned long flags;
+
+ local_irq_save(flags);

/*
- * The version register is read-only in a real APIC.
+ * Wait for IRQ0's slice:
*/
- reg0 = apic_read(APIC_LVR);
- apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg0);
- apic_write(APIC_LVR, reg0 ^ APIC_LVR_MASK);
- reg1 = apic_read(APIC_LVR);
- apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg1);
+ wait_timer_tick();
+
+ __setup_APIC_LVTT(clocks);
+
+ local_irq_restore(flags);
+}
+
+/*
+ * In this function we calibrate APIC bus clocks to the external
+ * timer. Unfortunately we cannot use jiffies and the timer irq
+ * to calibrate, since some later bootup code depends on getting
+ * the first irq? Ugh.
+ *
+ * We want to do the calibration only once since we
+ * want to have local timer irqs syncron. CPUs connected
+ * by the same APIC bus have the very same bus frequency.
+ * And we want to have irqs off anyways, no accidental
+ * APIC irq that way.
+ */
+
+static int __init calibrate_APIC_clock(void)
+{
+ unsigned long long t1 = 0, t2 = 0;
+ long tt1, tt2;
+ long result;
+ int i;
+ const int LOOPS = HZ/10;
+
+ apic_printk(APIC_VERBOSE, "calibrating APIC timer ...\n");

/*
- * The two version reads above should print the same
- * numbers. If the second one is different, then we
- * poke at a non-APIC.
+ * Put whatever arbitrary (but long enough) timeout
+ * value into the APIC clock, we just want to get the
+ * counter running for calibration.
*/
- if (reg1 != reg0)
- return 0;
+ __setup_APIC_LVTT(1000000000);

/*
- * Check if the version looks reasonably.
+ * The timer chip counts down to zero. Let's wait
+ * for a wraparound to start exact measurement:
+ * (the current tick might have been already half done)
*/
- reg1 = GET_APIC_VERSION(reg0);
- if (reg1 == 0x00 || reg1 == 0xff)
- return 0;
- reg1 = get_maxlvt();
- if (reg1 < 0x02 || reg1 == 0xff)
- return 0;
+
+ wait_timer_tick();

/*
- * The ID register is read/write in a real APIC.
+ * We wrapped around just now. Let's start:
*/
- reg0 = apic_read(APIC_ID);
- apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg0);
+ if (cpu_has_tsc)
+ rdtscll(t1);
+ tt1 = apic_read(APIC_TMCCT);

/*
- * The next two are just to see if we have sane values.
- * They're only really relevant if we're in Virtual Wire
- * compatibility mode, but most boxes are anymore.
+ * Let's wait LOOPS wraprounds:
*/
- reg0 = apic_read(APIC_LVT0);
- apic_printk(APIC_DEBUG, "Getting LVT0: %x\n", reg0);
- reg1 = apic_read(APIC_LVT1);
- apic_printk(APIC_DEBUG, "Getting LVT1: %x\n", reg1);
+ for (i = 0; i < LOOPS; i++)
+ wait_timer_tick();

- return 1;
-}
+ tt2 = apic_read(APIC_TMCCT);
+ if (cpu_has_tsc)
+ rdtscll(t2);

-void __init sync_Arb_IDs(void)
-{
- /* Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1
- And not needed on AMD */
- if (modern_apic())
- return;
/*
- * Wait for idle.
+ * The APIC bus clock counter is 32 bits only, it
+ * might have overflown, but note that we use signed
+ * longs, thus no extra care needed.
+ *
+ * underflown to be exact, as the timer counts down ;)
*/
- apic_wait_icr_idle();

- apic_printk(APIC_DEBUG, "Synchronizing Arb IDs.\n");
- apic_write_around(APIC_ICR, APIC_DEST_ALLINC | APIC_INT_LEVELTRIG
- | APIC_DM_INIT);
+ result = (tt1-tt2)*APIC_DIVISOR/LOOPS;
+
+ if (cpu_has_tsc)
+ apic_printk(APIC_VERBOSE, "..... CPU clock speed is "
+ "%ld.%04ld MHz.\n",
+ ((long)(t2-t1)/LOOPS)/(1000000/HZ),
+ ((long)(t2-t1)/LOOPS)%(1000000/HZ));
+
+ apic_printk(APIC_VERBOSE, "..... host bus clock speed is "
+ "%ld.%04ld MHz.\n",
+ result/(1000000/HZ),
+ result%(1000000/HZ));
+
+ return result;
}

-extern void __error_in_apic_c (void);
+static unsigned int calibration_result;

-/*
- * An initial setup of the virtual wire mode.
- */
-void __init init_bsp_APIC(void)
+void __init setup_boot_APIC_clock(void)
{
- unsigned long value, ver;
+ unsigned long flags;
+ apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n");
+ using_apic_timer = 1;
+
+ local_irq_save(flags);

+ calibration_result = calibrate_APIC_clock();
/*
- * Don't do the setup now if we have a SMP BIOS as the
- * through-I/O-APIC virtual wire mode might be active.
+ * Now set up the timer for real.
*/
- if (smp_found_config || !cpu_has_apic)
- return;
+ setup_APIC_timer(calibration_result);
+
+ local_irq_restore(flags);
+}

- value = apic_read(APIC_LVR);
- ver = GET_APIC_VERSION(value);
+void __devinit setup_secondary_APIC_clock(void)
+{
+ setup_APIC_timer(calibration_result);
+}

- /*
- * Do not trust the local APIC being empty at bootup.
- */
- clear_local_APIC();
+void disable_APIC_timer(void)
+{
+ if (using_apic_timer) {
+ unsigned long v;

- /*
- * Enable APIC.
- */
- value = apic_read(APIC_SPIV);
- value &= ~APIC_VECTOR_MASK;
- value |= APIC_SPIV_APIC_ENABLED;
-
- /* This bit is reserved on P4/Xeon and should be cleared */
- if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) && (boot_cpu_data.x86 == 15))
- value &= ~APIC_SPIV_FOCUS_DISABLED;
- else
- value |= APIC_SPIV_FOCUS_DISABLED;
- value |= SPURIOUS_APIC_VECTOR;
- apic_write_around(APIC_SPIV, value);
+ v = apic_read(APIC_LVTT);
+ /*
+ * When an illegal vector value (0-15) is written to an LVT
+ * entry and delivery mode is Fixed, the APIC may signal an
+ * illegal vector error, with out regard to whether the mask
+ * bit is set or whether an interrupt is actually seen on
+ * input.
+ *
+ * Boot sequence might call this function when the LVTT has
+ * '0' vector value. So make sure vector field is set to
+ * valid value.
+ */
+ v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
+ apic_write_around(APIC_LVTT, v);
+ }
+}

- /*
- * Set up the virtual wire mode.
- */
- apic_write_around(APIC_LVT0, APIC_DM_EXTINT);
- value = APIC_DM_NMI;
- if (!APIC_INTEGRATED(ver)) /* 82489DX */
- value |= APIC_LVT_LEVEL_TRIGGER;
- apic_write_around(APIC_LVT1, value);
+void enable_APIC_timer(void)
+{
+ int cpu = smp_processor_id();
+
+ if (using_apic_timer && !cpu_isset(cpu, timer_bcast_ipi)) {
+ unsigned long v;
+
+ v = apic_read(APIC_LVTT);
+ apic_write_around(APIC_LVTT, v & ~APIC_LVT_MASKED);
+ }
}

-void __devinit setup_local_APIC(void)
+void switch_APIC_timer_to_ipi(void *cpumask)
{
- unsigned long oldvalue, value, ver, maxlvt;
- int i, j;
+ cpumask_t mask = *(cpumask_t *)cpumask;
+ int cpu = smp_processor_id();

- /* Pound the ESR really hard over the head with a big hammer - mbligh */
- if (esr_disable) {
- apic_write(APIC_ESR, 0);
- apic_write(APIC_ESR, 0);
- apic_write(APIC_ESR, 0);
- apic_write(APIC_ESR, 0);
+ if (cpu_isset(cpu, mask) &&
+ !cpu_isset(cpu, timer_bcast_ipi)) {
+ disable_APIC_timer();
+ cpu_set(cpu, timer_bcast_ipi);
}
+}
+EXPORT_SYMBOL(switch_APIC_timer_to_ipi);
+
+void switch_ipi_to_APIC_timer(void *cpumask)
+{
+ cpumask_t mask = *(cpumask_t *)cpumask;
+ int cpu = smp_processor_id();

- value = apic_read(APIC_LVR);
- ver = GET_APIC_VERSION(value);
+ if (cpu_isset(cpu, mask) &&
+ cpu_isset(cpu, timer_bcast_ipi)) {
+ cpu_clear(cpu, timer_bcast_ipi);
+ enable_APIC_timer();
+ }
+}
+EXPORT_SYMBOL(switch_ipi_to_APIC_timer);

- if ((SPURIOUS_APIC_VECTOR & 0x0f) != 0x0f)
- __error_in_apic_c();
+/*
+ * Local timer interrupt handler. It does both profiling and
+ * process statistics/rescheduling.
+ */
+inline void smp_local_timer_interrupt(void)
+{
+ profile_tick(CPU_PROFILING);
+#ifdef CONFIG_SMP
+ update_process_times(user_mode_vm(get_irq_regs()));
+#endif

/*
- * Double-check whether this APIC is really registered.
+ * We take the 'long' return path, and there every subsystem
+ * grabs the apropriate locks (kernel lock/ irq lock).
+ *
+ * we might want to decouple profiling from the 'long path',
+ * and do the profiling totally in assembly.
+ *
+ * Currently this isn't too much of an issue (performance wise),
+ * we can take more than 100K local irqs per second on a 100 MHz P5.
*/
- if (!apic_id_registered())
- BUG();
+}
+
+/*
+ * Local APIC timer interrupt. This is the most natural way for doing
+ * local interrupts, but local timer interrupts can be emulated by
+ * broadcast interrupts too. [in case the hw doesn't support APIC timers]
+ *
+ * [ if a single-CPU system runs an SMP kernel then we call the local
+ * interrupt as well. Thus we cannot inline the local irq ... ]
+ */
+
+fastcall void smp_apic_timer_interrupt(struct pt_regs *regs)
+{
+ struct pt_regs *old_regs = set_irq_regs(regs);
+ int cpu = smp_processor_id();

/*
- * Intel recommends to set DFR, LDR and TPR before enabling
- * an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel
- * document number 292116). So here it goes...
+ * the NMI deadlock-detector uses this.
*/
- init_apic_ldr();
+ per_cpu(irq_stat, cpu).apic_timer_irqs++;

/*
- * Set Task Priority to 'accept all'. We never change this
- * later on.
+ * NOTE! We'd better ACK the irq immediately,
+ * because timer handling can be slow.
*/
- value = apic_read(APIC_TASKPRI);
- value &= ~APIC_TPRI_MASK;
- apic_write_around(APIC_TASKPRI, value);
-
+ ack_APIC_irq();
/*
- * After a crash, we no longer service the interrupts and a pending
- * interrupt from previous kernel might still have ISR bit set.
- *
- * Most probably by now CPU has serviced that pending interrupt and
- * it might not have done the ack_APIC_irq() because it thought,
- * interrupt came from i8259 as ExtInt. LAPIC did not get EOI so it
- * does not clear the ISR bit and cpu thinks it has already serivced
- * the interrupt. Hence a vector might get locked. It was noticed
- * for timer irq (vector 0x31). Issue an extra EOI to clear ISR.
+ * update_process_times() expects us to have done irq_enter().
+ * Besides, if we don't timer interrupts ignore the global
+ * interrupt lock, which is the WrongThing (tm) to do.
*/
- for (i = APIC_ISR_NR - 1; i >= 0; i--) {
- value = apic_read(APIC_ISR + i*0x10);
- for (j = 31; j >= 0; j--) {
- if (value & (1<<j))
- ack_APIC_irq();
- }
- }
+ irq_enter();
+ smp_local_timer_interrupt();
+ irq_exit();
+ set_irq_regs(old_regs);
+}

- /*
- * Now that we are all set up, enable the APIC
- */
- value = apic_read(APIC_SPIV);
- value &= ~APIC_VECTOR_MASK;
- /*
- * Enable APIC
- */
- value |= APIC_SPIV_APIC_ENABLED;
+#ifndef CONFIG_SMP
+static void up_apic_timer_interrupt_call(void)
+{
+ int cpu = smp_processor_id();

/*
- * Some unknown Intel IO/APIC (or APIC) errata is biting us with
- * certain networking cards. If high frequency interrupts are
- * happening on a particular IOAPIC pin, plus the IOAPIC routing
- * entry is masked/unmasked at a high rate as well then sooner or
- * later IOAPIC line gets 'stuck', no more interrupts are received
- * from the device. If focus CPU is disabled then the hang goes
- * away, oh well :-(
- *
- * [ This bug can be reproduced easily with a level-triggered
- * PCI Ne2000 networking cards and PII/PIII processors, dual
- * BX chipset. ]
- */
- /*
- * Actually disabling the focus CPU check just makes the hang less
- * frequent as it makes the interrupt distributon model be more
- * like LRU than MRU (the short-term load is more even across CPUs).
- * See also the comment in end_level_ioapic_irq(). --macro
+ * the NMI deadlock-detector uses this.
*/
-#if 1
- /* Enable focus processor (bit==0) */
- value &= ~APIC_SPIV_FOCUS_DISABLED;
+ per_cpu(irq_stat, cpu).apic_timer_irqs++;
+
+ smp_local_timer_interrupt();
+}
+#endif
+
+void smp_send_timer_broadcast_ipi(void)
+{
+ cpumask_t mask;
+
+ cpus_and(mask, cpu_online_map, timer_bcast_ipi);
+ if (!cpus_empty(mask)) {
+#ifdef CONFIG_SMP
+ send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
#else
- /* Disable focus processor (bit==1) */
- value |= APIC_SPIV_FOCUS_DISABLED;
+ /*
+ * We can directly call the apic timer interrupt handler
+ * in UP case. Minus all irq related functions
+ */
+ up_apic_timer_interrupt_call();
#endif
- /*
- * Set spurious IRQ vector
- */
- value |= SPURIOUS_APIC_VECTOR;
- apic_write_around(APIC_SPIV, value);
+ }
+}
+
+int setup_profiling_timer(unsigned int multiplier)
+{
+ return -EINVAL;
+}
+
+/*
+ * Local APIC start and shutdown
+ */
+
+/**
+ * clear_local_APIC - shutdown the local APIC
+ *
+ * This is called, when a CPU is disabled and before rebooting, so the state of
+ * the local APIC has no dangling leftovers. Also used to cleanout any BIOS
+ * leftovers during boot.
+ */
+void clear_local_APIC(void)
+{
+ int maxlvt = lapic_get_maxlvt();
+ unsigned long v;

/*
- * Set up LVT0, LVT1:
- *
- * set up through-local-APIC on the BP's LINT0. This is not
- * strictly necessery in pure symmetric-IO mode, but sometimes
- * we delegate interrupts to the 8259A.
+ * Masking an LVT entry can trigger a local APIC error
+ * if the vector is zero. Mask LVTERR first to prevent this.
*/
+ if (maxlvt >= 3) {
+ v = ERROR_APIC_VECTOR; /* any non-zero vector will do */
+ apic_write_around(APIC_LVTERR, v | APIC_LVT_MASKED);
+ }
/*
- * TODO: set up through-local-APIC from through-I/O-APIC? --macro
+ * Careful: we have to set masks only first to deassert
+ * any level-triggered sources.
*/
- value = apic_read(APIC_LVT0) & APIC_LVT_MASKED;
- if (!smp_processor_id() && (pic_mode || !value)) {
- value = APIC_DM_EXTINT;
- apic_printk(APIC_VERBOSE, "enabled ExtINT on CPU#%d\n",
- smp_processor_id());
- } else {
- value = APIC_DM_EXTINT | APIC_LVT_MASKED;
- apic_printk(APIC_VERBOSE, "masked ExtINT on CPU#%d\n",
- smp_processor_id());
+ v = apic_read(APIC_LVTT);
+ apic_write_around(APIC_LVTT, v | APIC_LVT_MASKED);
+ v = apic_read(APIC_LVT0);
+ apic_write_around(APIC_LVT0, v | APIC_LVT_MASKED);
+ v = apic_read(APIC_LVT1);
+ apic_write_around(APIC_LVT1, v | APIC_LVT_MASKED);
+ if (maxlvt >= 4) {
+ v = apic_read(APIC_LVTPC);
+ apic_write_around(APIC_LVTPC, v | APIC_LVT_MASKED);
}
- apic_write_around(APIC_LVT0, value);

+ /* lets not touch this if we didn't frob it */
+#ifdef CONFIG_X86_MCE_P4THERMAL
+ if (maxlvt >= 5) {
+ v = apic_read(APIC_LVTTHMR);
+ apic_write_around(APIC_LVTTHMR, v | APIC_LVT_MASKED);
+ }
+#endif
/*
- * only the BP should see the LINT1 NMI signal, obviously.
+ * Clean APIC state for other OSs:
*/
- if (!smp_processor_id())
- value = APIC_DM_NMI;
- else
- value = APIC_DM_NMI | APIC_LVT_MASKED;
- if (!APIC_INTEGRATED(ver)) /* 82489DX */
- value |= APIC_LVT_LEVEL_TRIGGER;
- apic_write_around(APIC_LVT1, value);
-
- if (APIC_INTEGRATED(ver) && !esr_disable) { /* !82489DX */
- maxlvt = get_maxlvt();
- if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
- apic_write(APIC_ESR, 0);
- oldvalue = apic_read(APIC_ESR);
+ apic_write_around(APIC_LVTT, APIC_LVT_MASKED);
+ apic_write_around(APIC_LVT0, APIC_LVT_MASKED);
+ apic_write_around(APIC_LVT1, APIC_LVT_MASKED);
+ if (maxlvt >= 3)
+ apic_write_around(APIC_LVTERR, APIC_LVT_MASKED);
+ if (maxlvt >= 4)
+ apic_write_around(APIC_LVTPC, APIC_LVT_MASKED);

- value = ERROR_APIC_VECTOR; // enables sending errors
- apic_write_around(APIC_LVTERR, value);
- /*
- * spec says clear errors after enabling vector.
- */
+#ifdef CONFIG_X86_MCE_P4THERMAL
+ if (maxlvt >= 5)
+ apic_write_around(APIC_LVTTHMR, APIC_LVT_MASKED);
+#endif
+ /* Integrated APIC (!82489DX) ? */
+ if (lapic_is_integrated()) {
if (maxlvt > 3)
+ /* Clear ESR due to Pentium errata 3AP and 11AP */
apic_write(APIC_ESR, 0);
- value = apic_read(APIC_ESR);
- if (value != oldvalue)
- apic_printk(APIC_VERBOSE, "ESR value before enabling "
- "vector: 0x%08lx after: 0x%08lx\n",
- oldvalue, value);
- } else {
- if (esr_disable)
- /*
- * Something untraceble is creating bad interrupts on
- * secondary quads ... for the moment, just leave the
- * ESR disabled - we can't do anything useful with the
- * errors anyway - mbligh
- */
- printk("Leaving ESR disabled.\n");
- else
- printk("No ESR for 82489DX.\n");
+ apic_read(APIC_ESR);
}
+}

- setup_apic_nmi_watchdog(NULL);
- apic_pm_activate();
+/**
+ * disable_local_APIC - clear and disable the local APIC
+ */
+void disable_local_APIC(void)
+{
+ unsigned long value;
+
+ clear_local_APIC();
+
+ /*
+ * Disable APIC (implies clearing of registers
+ * for 82489DX!).
+ */
+ value = apic_read(APIC_SPIV);
+ value &= ~APIC_SPIV_APIC_ENABLED;
+ apic_write_around(APIC_SPIV, value);
+
+ /*
+ * When LAPIC was disabled by the BIOS and enabled by the kernel,
+ * restore the disabled state.
+ */
+ if (enabled_via_apicbase) {
+ unsigned int l, h;
+
+ rdmsr(MSR_IA32_APICBASE, l, h);
+ l &= ~MSR_IA32_APICBASE_ENABLE;
+ wrmsr(MSR_IA32_APICBASE, l, h);
+ }
}

/*
- * If Linux enabled the LAPIC against the BIOS default
- * disable it down before re-entering the BIOS on shutdown.
- * Otherwise the BIOS may get confused and not power-off.
- * Additionally clear all LVT entries before disable_local_APIC
+ * If Linux enabled the LAPIC against the BIOS default disable it down before
+ * re-entering the BIOS on shutdown. Otherwise the BIOS may get confused and
+ * not power-off. Additionally clear all LVT entries before disable_local_APIC
* for the case where Linux didn't enable the LAPIC.
*/
void lapic_shutdown(void)
@@ -624,168 +629,296 @@ void lapic_shutdown(void)
local_irq_restore(flags);
}

-#ifdef CONFIG_PM
-
-static struct {
- int active;
- /* r/w apic fields */
- unsigned int apic_id;
- unsigned int apic_taskpri;
- unsigned int apic_ldr;
- unsigned int apic_dfr;
- unsigned int apic_spiv;
- unsigned int apic_lvtt;
- unsigned int apic_lvtpc;
- unsigned int apic_lvt0;
- unsigned int apic_lvt1;
- unsigned int apic_lvterr;
- unsigned int apic_tmict;
- unsigned int apic_tdcr;
- unsigned int apic_thmr;
-} apic_pm_state;
-
-static int lapic_suspend(struct sys_device *dev, pm_message_t state)
+/*
+ * This is to verify that we're looking at a real local APIC.
+ * Check these against your board if the CPUs aren't getting
+ * started for no apparent reason.
+ */
+int __init verify_local_APIC(void)
{
- unsigned long flags;
- int maxlvt;
+ unsigned int reg0, reg1;

- if (!apic_pm_state.active)
- return 0;
+ /*
+ * The version register is read-only in a real APIC.
+ */
+ reg0 = apic_read(APIC_LVR);
+ apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg0);
+ apic_write(APIC_LVR, reg0 ^ APIC_LVR_MASK);
+ reg1 = apic_read(APIC_LVR);
+ apic_printk(APIC_DEBUG, "Getting VERSION: %x\n", reg1);

- maxlvt = get_maxlvt();
+ /*
+ * The two version reads above should print the same
+ * numbers. If the second one is different, then we
+ * poke at a non-APIC.
+ */
+ if (reg1 != reg0)
+ return 0;

- apic_pm_state.apic_id = apic_read(APIC_ID);
- apic_pm_state.apic_taskpri = apic_read(APIC_TASKPRI);
- apic_pm_state.apic_ldr = apic_read(APIC_LDR);
- apic_pm_state.apic_dfr = apic_read(APIC_DFR);
- apic_pm_state.apic_spiv = apic_read(APIC_SPIV);
- apic_pm_state.apic_lvtt = apic_read(APIC_LVTT);
- if (maxlvt >= 4)
- apic_pm_state.apic_lvtpc = apic_read(APIC_LVTPC);
- apic_pm_state.apic_lvt0 = apic_read(APIC_LVT0);
- apic_pm_state.apic_lvt1 = apic_read(APIC_LVT1);
- apic_pm_state.apic_lvterr = apic_read(APIC_LVTERR);
- apic_pm_state.apic_tmict = apic_read(APIC_TMICT);
- apic_pm_state.apic_tdcr = apic_read(APIC_TDCR);
-#ifdef CONFIG_X86_MCE_P4THERMAL
- if (maxlvt >= 5)
- apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
-#endif
-
- local_irq_save(flags);
- disable_local_APIC();
- local_irq_restore(flags);
- return 0;
-}
-
-static int lapic_resume(struct sys_device *dev)
-{
- unsigned int l, h;
- unsigned long flags;
- int maxlvt;
-
- if (!apic_pm_state.active)
+ /*
+ * Check if the version looks reasonably.
+ */
+ reg1 = GET_APIC_VERSION(reg0);
+ if (reg1 == 0x00 || reg1 == 0xff)
+ return 0;
+ reg1 = lapic_get_maxlvt();
+ if (reg1 < 0x02 || reg1 == 0xff)
return 0;

- maxlvt = get_maxlvt();
+ /*
+ * The ID register is read/write in a real APIC.
+ */
+ reg0 = apic_read(APIC_ID);
+ apic_printk(APIC_DEBUG, "Getting ID: %x\n", reg0);
+
+ /*
+ * The next two are just to see if we have sane values.
+ * They're only really relevant if we're in Virtual Wire
+ * compatibility mode, but most boxes are anymore.
+ */
+ reg0 = apic_read(APIC_LVT0);
+ apic_printk(APIC_DEBUG, "Getting LVT0: %x\n", reg0);
+ reg1 = apic_read(APIC_LVT1);
+ apic_printk(APIC_DEBUG, "Getting LVT1: %x\n", reg1);

- local_irq_save(flags);
+ return 1;
+}

+/**
+ * sync_Arb_IDs - synchronize APIC bus arbitration IDs
+ */
+void __init sync_Arb_IDs(void)
+{
/*
- * Make sure the APICBASE points to the right address
- *
- * FIXME! This will be wrong if we ever support suspend on
- * SMP! We'll need to do this as part of the CPU restore!
+ * Unsupported on P4 - see Intel Dev. Manual Vol. 3, Ch. 8.6.1 And not
+ * needed on AMD.
*/
- rdmsr(MSR_IA32_APICBASE, l, h);
- l &= ~MSR_IA32_APICBASE_BASE;
- l |= MSR_IA32_APICBASE_ENABLE | mp_lapic_addr;
- wrmsr(MSR_IA32_APICBASE, l, h);
+ if (modern_apic())
+ return;
+ /*
+ * Wait for idle.
+ */
+ apic_wait_icr_idle();

- apic_write(APIC_LVTERR, ERROR_APIC_VECTOR | APIC_LVT_MASKED);
- apic_write(APIC_ID, apic_pm_state.apic_id);
- apic_write(APIC_DFR, apic_pm_state.apic_dfr);
- apic_write(APIC_LDR, apic_pm_state.apic_ldr);
- apic_write(APIC_TASKPRI, apic_pm_state.apic_taskpri);
- apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
- apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
- apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
-#ifdef CONFIG_X86_MCE_P4THERMAL
- if (maxlvt >= 5)
- apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
-#endif
- if (maxlvt >= 4)
- apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
- apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
- apic_write(APIC_TDCR, apic_pm_state.apic_tdcr);
- apic_write(APIC_TMICT, apic_pm_state.apic_tmict);
- apic_write(APIC_ESR, 0);
- apic_read(APIC_ESR);
- apic_write(APIC_LVTERR, apic_pm_state.apic_lvterr);
- apic_write(APIC_ESR, 0);
- apic_read(APIC_ESR);
- local_irq_restore(flags);
- return 0;
+ apic_printk(APIC_DEBUG, "Synchronizing Arb IDs.\n");
+ apic_write_around(APIC_ICR, APIC_DEST_ALLINC | APIC_INT_LEVELTRIG
+ | APIC_DM_INIT);
}

/*
- * This device has no shutdown method - fully functioning local APICs
- * are needed on every CPU up until machine_halt/restart/poweroff.
+ * An initial setup of the virtual wire mode.
*/
+void __init init_bsp_APIC(void)
+{
+ unsigned long value;

-static struct sysdev_class lapic_sysclass = {
- set_kset_name("lapic"),
- .resume = lapic_resume,
- .suspend = lapic_suspend,
-};
+ /*
+ * Don't do the setup now if we have a SMP BIOS as the
+ * through-I/O-APIC virtual wire mode might be active.
+ */
+ if (smp_found_config || !cpu_has_apic)
+ return;

-static struct sys_device device_lapic = {
- .id = 0,
- .cls = &lapic_sysclass,
-};
+ /*
+ * Do not trust the local APIC being empty at bootup.
+ */
+ clear_local_APIC();

-static void __devinit apic_pm_activate(void)
-{
- apic_pm_state.active = 1;
+ /*
+ * Enable APIC.
+ */
+ value = apic_read(APIC_SPIV);
+ value &= ~APIC_VECTOR_MASK;
+ value |= APIC_SPIV_APIC_ENABLED;
+
+ /* This bit is reserved on P4/Xeon and should be cleared */
+ if ((boot_cpu_data.x86_vendor == X86_VENDOR_INTEL) &&
+ (boot_cpu_data.x86 == 15))
+ value &= ~APIC_SPIV_FOCUS_DISABLED;
+ else
+ value |= APIC_SPIV_FOCUS_DISABLED;
+ value |= SPURIOUS_APIC_VECTOR;
+ apic_write_around(APIC_SPIV, value);
+
+ /*
+ * Set up the virtual wire mode.
+ */
+ apic_write_around(APIC_LVT0, APIC_DM_EXTINT);
+ value = APIC_DM_NMI;
+ if (!lapic_is_integrated()) /* 82489DX */
+ value |= APIC_LVT_LEVEL_TRIGGER;
+ apic_write_around(APIC_LVT1, value);
}

-static int __init init_lapic_sysfs(void)
+/**
+ * setup_local_APIC - setup the local APIC
+ */
+void __devinit setup_local_APIC(void)
{
- int error;
+ unsigned long oldvalue, value, maxlvt, integrated;
+ int i, j;

- if (!cpu_has_apic)
- return 0;
- /* XXX: remove suspend/resume procs if !apic_pm_state.active? */
+ /* Pound the ESR really hard over the head with a big hammer - mbligh */
+ if (esr_disable) {
+ apic_write(APIC_ESR, 0);
+ apic_write(APIC_ESR, 0);
+ apic_write(APIC_ESR, 0);
+ apic_write(APIC_ESR, 0);
+ }

- error = sysdev_class_register(&lapic_sysclass);
- if (!error)
- error = sysdev_register(&device_lapic);
- return error;
-}
-device_initcall(init_lapic_sysfs);
+ integrated = lapic_is_integrated();

-#else /* CONFIG_PM */
+ /*
+ * Double-check whether this APIC is really registered.
+ */
+ if (!apic_id_registered())
+ BUG();

-static void apic_pm_activate(void) { }
+ /*
+ * Intel recommends to set DFR, LDR and TPR before enabling
+ * an APIC. See e.g. "AP-388 82489DX User's Manual" (Intel
+ * document number 292116). So here it goes...
+ */
+ init_apic_ldr();

-#endif /* CONFIG_PM */
+ /*
+ * Set Task Priority to 'accept all'. We never change this
+ * later on.
+ */
+ value = apic_read(APIC_TASKPRI);
+ value &= ~APIC_TPRI_MASK;
+ apic_write_around(APIC_TASKPRI, value);

-/*
- * Detect and enable local APICs on non-SMP boards.
- * Original code written by Keir Fraser.
- */
+ /*
+ * After a crash, we no longer service the interrupts and a pending
+ * interrupt from previous kernel might still have ISR bit set.
+ *
+ * Most probably by now CPU has serviced that pending interrupt and
+ * it might not have done the ack_APIC_irq() because it thought,
+ * interrupt came from i8259 as ExtInt. LAPIC did not get EOI so it
+ * does not clear the ISR bit and cpu thinks it has already serivced
+ * the interrupt. Hence a vector might get locked. It was noticed
+ * for timer irq (vector 0x31). Issue an extra EOI to clear ISR.
+ */
+ for (i = APIC_ISR_NR - 1; i >= 0; i--) {
+ value = apic_read(APIC_ISR + i*0x10);
+ for (j = 31; j >= 0; j--) {
+ if (value & (1<<j))
+ ack_APIC_irq();
+ }
+ }
+
+ /*
+ * Now that we are all set up, enable the APIC
+ */
+ value = apic_read(APIC_SPIV);
+ value &= ~APIC_VECTOR_MASK;
+ /*
+ * Enable APIC
+ */
+ value |= APIC_SPIV_APIC_ENABLED;
+
+ /*
+ * Some unknown Intel IO/APIC (or APIC) errata is biting us with
+ * certain networking cards. If high frequency interrupts are
+ * happening on a particular IOAPIC pin, plus the IOAPIC routing
+ * entry is masked/unmasked at a high rate as well then sooner or
+ * later IOAPIC line gets 'stuck', no more interrupts are received
+ * from the device. If focus CPU is disabled then the hang goes
+ * away, oh well :-(
+ *
+ * [ This bug can be reproduced easily with a level-triggered
+ * PCI Ne2000 networking cards and PII/PIII processors, dual
+ * BX chipset. ]
+ */
+ /*
+ * Actually disabling the focus CPU check just makes the hang less
+ * frequent as it makes the interrupt distributon model be more
+ * like LRU than MRU (the short-term load is more even across CPUs).
+ * See also the comment in end_level_ioapic_irq(). --macro
+ */
+
+ /* Enable focus processor (bit==0) */
+ value &= ~APIC_SPIV_FOCUS_DISABLED;
+
+ /*
+ * Set spurious IRQ vector
+ */
+ value |= SPURIOUS_APIC_VECTOR;
+ apic_write_around(APIC_SPIV, value);
+
+ /*
+ * Set up LVT0, LVT1:
+ *
+ * set up through-local-APIC on the BP's LINT0. This is not
+ * strictly necessery in pure symmetric-IO mode, but sometimes
+ * we delegate interrupts to the 8259A.
+ */
+ /*
+ * TODO: set up through-local-APIC from through-I/O-APIC? --macro
+ */
+ value = apic_read(APIC_LVT0) & APIC_LVT_MASKED;
+ if (!smp_processor_id() && (pic_mode || !value)) {
+ value = APIC_DM_EXTINT;
+ apic_printk(APIC_VERBOSE, "enabled ExtINT on CPU#%d\n",
+ smp_processor_id());
+ } else {
+ value = APIC_DM_EXTINT | APIC_LVT_MASKED;
+ apic_printk(APIC_VERBOSE, "masked ExtINT on CPU#%d\n",
+ smp_processor_id());
+ }
+ apic_write_around(APIC_LVT0, value);
+
+ /*
+ * only the BP should see the LINT1 NMI signal, obviously.
+ */
+ if (!smp_processor_id())
+ value = APIC_DM_NMI;
+ else
+ value = APIC_DM_NMI | APIC_LVT_MASKED;
+ if (!integrated) /* 82489DX */
+ value |= APIC_LVT_LEVEL_TRIGGER;
+ apic_write_around(APIC_LVT1, value);
+
+ if (integrated && !esr_disable) { /* !82489DX */
+ maxlvt = lapic_get_maxlvt();
+ if (maxlvt > 3) /* Due to the Pentium erratum 3AP. */
+ apic_write(APIC_ESR, 0);
+ oldvalue = apic_read(APIC_ESR);
+
+ /* enables sending errors */
+ value = ERROR_APIC_VECTOR;
+ apic_write_around(APIC_LVTERR, value);
+ /*
+ * spec says clear errors after enabling vector.
+ */
+ if (maxlvt > 3)
+ apic_write(APIC_ESR, 0);
+ value = apic_read(APIC_ESR);
+ if (value != oldvalue)
+ apic_printk(APIC_VERBOSE, "ESR value before enabling "
+ "vector: 0x%08lx after: 0x%08lx\n",
+ oldvalue, value);
+ } else {
+ if (esr_disable)
+ /*
+ * Something untraceble is creating bad interrupts on
+ * secondary quads ... for the moment, just leave the
+ * ESR disabled - we can't do anything useful with the
+ * errors anyway - mbligh
+ */
+ printk(KERN_INFO "Leaving ESR disabled.\n");
+ else
+ printk(KERN_INFO "No ESR for 82489DX.\n");
+ }

-static int __init apic_set_verbosity(char *str)
-{
- if (strcmp("debug", str) == 0)
- apic_verbosity = APIC_DEBUG;
- else if (strcmp("verbose", str) == 0)
- apic_verbosity = APIC_VERBOSE;
- return 1;
+ setup_apic_nmi_watchdog(NULL);
+ apic_pm_activate();
}

-__setup("apic=", apic_set_verbosity);
-
+/*
+ * Detect and initialize APIC
+ */
static int __init detect_init_APIC (void)
{
u32 h, l, features;
@@ -797,7 +930,7 @@ static int __init detect_init_APIC (void
switch (boot_cpu_data.x86_vendor) {
case X86_VENDOR_AMD:
if ((boot_cpu_data.x86 == 6 && boot_cpu_data.x86_model > 1) ||
- (boot_cpu_data.x86 == 15))
+ (boot_cpu_data.x86 == 15))
break;
goto no_apic;
case X86_VENDOR_INTEL:
@@ -811,23 +944,23 @@ static int __init detect_init_APIC (void

if (!cpu_has_apic) {
/*
- * Over-ride BIOS and try to enable the local
- * APIC only if "lapic" specified.
+ * Over-ride BIOS and try to enable the local APIC only if
+ * "lapic" specified.
*/
if (enable_local_apic <= 0) {
- printk("Local APIC disabled by BIOS -- "
+ printk(KERN_INFO "Local APIC disabled by BIOS -- "
"you can enable it with \"lapic\"\n");
return -1;
}
/*
- * Some BIOSes disable the local APIC in the
- * APIC_BASE MSR. This can only be done in
- * software for Intel P6 or later and AMD K7
- * (Model > 1) or later.
+ * Some BIOSes disable the local APIC in the APIC_BASE
+ * MSR. This can only be done in software for Intel P6 or later
+ * and AMD K7 (Model > 1) or later.
*/
rdmsr(MSR_IA32_APICBASE, l, h);
if (!(l & MSR_IA32_APICBASE_ENABLE)) {
- printk("Local APIC disabled by BIOS -- reenabling.\n");
+ printk(KERN_INFO
+ "Local APIC disabled by BIOS -- reenabling.\n");
l &= ~MSR_IA32_APICBASE_BASE;
l |= MSR_IA32_APICBASE_ENABLE | APIC_DEFAULT_PHYS_BASE;
wrmsr(MSR_IA32_APICBASE, l, h);
@@ -840,464 +973,175 @@ static int __init detect_init_APIC (void
*/
features = cpuid_edx(1);
if (!(features & (1 << X86_FEATURE_APIC))) {
- printk("Could not enable APIC!\n");
+ printk(KERN_WARNING "Could not enable APIC!\n");
return -1;
}
set_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);
mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;

/* The BIOS may have set up the APIC at some other address */
- rdmsr(MSR_IA32_APICBASE, l, h);
- if (l & MSR_IA32_APICBASE_ENABLE)
- mp_lapic_addr = l & MSR_IA32_APICBASE_BASE;
-
- if (nmi_watchdog != NMI_NONE)
- nmi_watchdog = NMI_LOCAL_APIC;
-
- printk("Found and enabled local APIC!\n");
-
- apic_pm_activate();
-
- return 0;
-
-no_apic:
- printk("No local APIC present or hardware disabled\n");
- return -1;
-}
-
-void __init init_apic_mappings(void)
-{
- unsigned long apic_phys;
-
- /*
- * If no local APIC can be found then set up a fake all
- * zeroes page to simulate the local APIC and another
- * one for the IO-APIC.
- */
- if (!smp_found_config && detect_init_APIC()) {
- apic_phys = (unsigned long) alloc_bootmem_pages(PAGE_SIZE);
- apic_phys = __pa(apic_phys);
- } else
- apic_phys = mp_lapic_addr;
-
- set_fixmap_nocache(FIX_APIC_BASE, apic_phys);
- printk(KERN_DEBUG "mapped APIC to %08lx (%08lx)\n", APIC_BASE,
- apic_phys);
-
- /*
- * Fetch the APIC ID of the BSP in case we have a
- * default configuration (or the MP table is broken).
- */
- if (boot_cpu_physical_apicid == -1U)
- boot_cpu_physical_apicid = GET_APIC_ID(apic_read(APIC_ID));
-
-#ifdef CONFIG_X86_IO_APIC
- {
- unsigned long ioapic_phys, idx = FIX_IO_APIC_BASE_0;
- int i;
-
- for (i = 0; i < nr_ioapics; i++) {
- if (smp_found_config) {
- ioapic_phys = mp_ioapics[i].mpc_apicaddr;
- if (!ioapic_phys) {
- printk(KERN_ERR
- "WARNING: bogus zero IO-APIC "
- "address found in MPTABLE, "
- "disabling IO/APIC support!\n");
- smp_found_config = 0;
- skip_ioapic_setup = 1;
- goto fake_ioapic_page;
- }
- } else {
-fake_ioapic_page:
- ioapic_phys = (unsigned long)
- alloc_bootmem_pages(PAGE_SIZE);
- ioapic_phys = __pa(ioapic_phys);
- }
- set_fixmap_nocache(idx, ioapic_phys);
- printk(KERN_DEBUG "mapped IOAPIC to %08lx (%08lx)\n",
- __fix_to_virt(idx), ioapic_phys);
- idx++;
- }
- }
-#endif
-}
-
-/*
- * This part sets up the APIC 32 bit clock in LVTT1, with HZ interrupts
- * per second. We assume that the caller has already set up the local
- * APIC.
- *
- * The APIC timer is not exactly sync with the external timer chip, it
- * closely follows bus clocks.
- */
-
-/*
- * The timer chip is already set up at HZ interrupts per second here,
- * but we do not accept timer interrupts yet. We only allow the BP
- * to calibrate.
- */
-static unsigned int __devinit get_8254_timer_count(void)
-{
- unsigned long flags;
-
- unsigned int count;
-
- spin_lock_irqsave(&i8253_lock, flags);
-
- outb_p(0x00, PIT_MODE);
- count = inb_p(PIT_CH0);
- count |= inb_p(PIT_CH0) << 8;
-
- spin_unlock_irqrestore(&i8253_lock, flags);
-
- return count;
-}
-
-/* next tick in 8254 can be caught by catching timer wraparound */
-static void __devinit wait_8254_wraparound(void)
-{
- unsigned int curr_count, prev_count;
-
- curr_count = get_8254_timer_count();
- do {
- prev_count = curr_count;
- curr_count = get_8254_timer_count();
-
- /* workaround for broken Mercury/Neptune */
- if (prev_count >= curr_count + 0x100)
- curr_count = get_8254_timer_count();
-
- } while (prev_count >= curr_count);
-}
-
-/*
- * Default initialization for 8254 timers. If we use other timers like HPET,
- * we override this later
- */
-void (*wait_timer_tick)(void) __devinitdata = wait_8254_wraparound;
-
-/*
- * This function sets up the local APIC timer, with a timeout of
- * 'clocks' APIC bus clock. During calibration we actually call
- * this function twice on the boot CPU, once with a bogus timeout
- * value, second time for real. The other (noncalibrating) CPUs
- * call this function only once, with the real, calibrated value.
- *
- * We do reads before writes even if unnecessary, to get around the
- * P5 APIC double write bug.
- */
-
-#define APIC_DIVISOR 16
-
-static void __setup_APIC_LVTT(unsigned int clocks)
-{
- unsigned int lvtt_value, tmp_value, ver;
- int cpu = smp_processor_id();
-
- ver = GET_APIC_VERSION(apic_read(APIC_LVR));
- lvtt_value = APIC_LVT_TIMER_PERIODIC | LOCAL_TIMER_VECTOR;
- if (!APIC_INTEGRATED(ver))
- lvtt_value |= SET_APIC_TIMER_BASE(APIC_TIMER_BASE_DIV);
-
- if (cpu_isset(cpu, timer_bcast_ipi))
- lvtt_value |= APIC_LVT_MASKED;
-
- apic_write_around(APIC_LVTT, lvtt_value);
-
- /*
- * Divide PICLK by 16
- */
- tmp_value = apic_read(APIC_TDCR);
- apic_write_around(APIC_TDCR, (tmp_value
- & ~(APIC_TDR_DIV_1 | APIC_TDR_DIV_TMBASE))
- | APIC_TDR_DIV_16);
-
- apic_write_around(APIC_TMICT, clocks/APIC_DIVISOR);
-}
-
-static void __devinit setup_APIC_timer(unsigned int clocks)
-{
- unsigned long flags;
-
- local_irq_save(flags);
-
- /*
- * Wait for IRQ0's slice:
- */
- wait_timer_tick();
-
- __setup_APIC_LVTT(clocks);
-
- local_irq_restore(flags);
-}
-
-/*
- * In this function we calibrate APIC bus clocks to the external
- * timer. Unfortunately we cannot use jiffies and the timer irq
- * to calibrate, since some later bootup code depends on getting
- * the first irq? Ugh.
- *
- * We want to do the calibration only once since we
- * want to have local timer irqs syncron. CPUs connected
- * by the same APIC bus have the very same bus frequency.
- * And we want to have irqs off anyways, no accidental
- * APIC irq that way.
- */
-
-static int __init calibrate_APIC_clock(void)
-{
- unsigned long long t1 = 0, t2 = 0;
- long tt1, tt2;
- long result;
- int i;
- const int LOOPS = HZ/10;
-
- apic_printk(APIC_VERBOSE, "calibrating APIC timer ...\n");
-
- /*
- * Put whatever arbitrary (but long enough) timeout
- * value into the APIC clock, we just want to get the
- * counter running for calibration.
- */
- __setup_APIC_LVTT(1000000000);
-
- /*
- * The timer chip counts down to zero. Let's wait
- * for a wraparound to start exact measurement:
- * (the current tick might have been already half done)
- */
-
- wait_timer_tick();
-
- /*
- * We wrapped around just now. Let's start:
- */
- if (cpu_has_tsc)
- rdtscll(t1);
- tt1 = apic_read(APIC_TMCCT);
-
- /*
- * Let's wait LOOPS wraprounds:
- */
- for (i = 0; i < LOOPS; i++)
- wait_timer_tick();
-
- tt2 = apic_read(APIC_TMCCT);
- if (cpu_has_tsc)
- rdtscll(t2);
-
- /*
- * The APIC bus clock counter is 32 bits only, it
- * might have overflown, but note that we use signed
- * longs, thus no extra care needed.
- *
- * underflown to be exact, as the timer counts down ;)
- */
+ rdmsr(MSR_IA32_APICBASE, l, h);
+ if (l & MSR_IA32_APICBASE_ENABLE)
+ mp_lapic_addr = l & MSR_IA32_APICBASE_BASE;

- result = (tt1-tt2)*APIC_DIVISOR/LOOPS;
+ if (nmi_watchdog != NMI_NONE)
+ nmi_watchdog = NMI_LOCAL_APIC;

- if (cpu_has_tsc)
- apic_printk(APIC_VERBOSE, "..... CPU clock speed is "
- "%ld.%04ld MHz.\n",
- ((long)(t2-t1)/LOOPS)/(1000000/HZ),
- ((long)(t2-t1)/LOOPS)%(1000000/HZ));
+ printk(KERN_INFO "Found and enabled local APIC!\n");

- apic_printk(APIC_VERBOSE, "..... host bus clock speed is "
- "%ld.%04ld MHz.\n",
- result/(1000000/HZ),
- result%(1000000/HZ));
+ apic_pm_activate();

- return result;
-}
+ return 0;

-static unsigned int calibration_result;
+no_apic:
+ printk(KERN_INFO "No local APIC present or hardware disabled\n");
+ return -1;
+}

-void __init setup_boot_APIC_clock(void)
+/**
+ * init_apic_mappings - initialize APIC mappings
+ */
+void __init init_apic_mappings(void)
{
- unsigned long flags;
- apic_printk(APIC_VERBOSE, "Using local APIC timer interrupts.\n");
- using_apic_timer = 1;
-
- local_irq_save(flags);
+ unsigned long apic_phys;

- calibration_result = calibrate_APIC_clock();
/*
- * Now set up the timer for real.
+ * If no local APIC can be found then set up a fake all
+ * zeroes page to simulate the local APIC and another
+ * one for the IO-APIC.
*/
- setup_APIC_timer(calibration_result);
+ if (!smp_found_config && detect_init_APIC()) {
+ apic_phys = (unsigned long) alloc_bootmem_pages(PAGE_SIZE);
+ apic_phys = __pa(apic_phys);
+ } else
+ apic_phys = mp_lapic_addr;

- local_irq_restore(flags);
-}
+ set_fixmap_nocache(FIX_APIC_BASE, apic_phys);
+ printk(KERN_DEBUG "mapped APIC to %08lx (%08lx)\n", APIC_BASE,
+ apic_phys);

-void __devinit setup_secondary_APIC_clock(void)
-{
- setup_APIC_timer(calibration_result);
-}
+ /*
+ * Fetch the APIC ID of the BSP in case we have a
+ * default configuration (or the MP table is broken).
+ */
+ if (boot_cpu_physical_apicid == -1U)
+ boot_cpu_physical_apicid = GET_APIC_ID(apic_read(APIC_ID));

-void disable_APIC_timer(void)
-{
- if (using_apic_timer) {
- unsigned long v;
+#ifdef CONFIG_X86_IO_APIC
+ {
+ unsigned long ioapic_phys, idx = FIX_IO_APIC_BASE_0;
+ int i;

- v = apic_read(APIC_LVTT);
- /*
- * When an illegal vector value (0-15) is written to an LVT
- * entry and delivery mode is Fixed, the APIC may signal an
- * illegal vector error, with out regard to whether the mask
- * bit is set or whether an interrupt is actually seen on input.
- *
- * Boot sequence might call this function when the LVTT has
- * '0' vector value. So make sure vector field is set to
- * valid value.
- */
- v |= (APIC_LVT_MASKED | LOCAL_TIMER_VECTOR);
- apic_write_around(APIC_LVTT, v);
+ for (i = 0; i < nr_ioapics; i++) {
+ if (smp_found_config) {
+ ioapic_phys = mp_ioapics[i].mpc_apicaddr;
+ if (!ioapic_phys) {
+ printk(KERN_ERR
+ "WARNING: bogus zero IO-APIC "
+ "address found in MPTABLE, "
+ "disabling IO/APIC support!\n");
+ smp_found_config = 0;
+ skip_ioapic_setup = 1;
+ goto fake_ioapic_page;
+ }
+ } else {
+fake_ioapic_page:
+ ioapic_phys = (unsigned long)
+ alloc_bootmem_pages(PAGE_SIZE);
+ ioapic_phys = __pa(ioapic_phys);
+ }
+ set_fixmap_nocache(idx, ioapic_phys);
+ printk(KERN_DEBUG "mapped IOAPIC to %08lx (%08lx)\n",
+ __fix_to_virt(idx), ioapic_phys);
+ idx++;
+ }
}
+#endif
}

-void enable_APIC_timer(void)
+/*
+ * This initializes the IO-APIC and APIC hardware if this is
+ * a UP kernel.
+ */
+int __init APIC_init_uniprocessor (void)
{
- int cpu = smp_processor_id();
-
- if (using_apic_timer &&
- !cpu_isset(cpu, timer_bcast_ipi)) {
- unsigned long v;
-
- v = apic_read(APIC_LVTT);
- apic_write_around(APIC_LVTT, v & ~APIC_LVT_MASKED);
- }
-}
+ if (enable_local_apic < 0)
+ clear_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);

-void switch_APIC_timer_to_ipi(void *cpumask)
-{
- cpumask_t mask = *(cpumask_t *)cpumask;
- int cpu = smp_processor_id();
+ if (!smp_found_config && !cpu_has_apic)
+ return -1;

- if (cpu_isset(cpu, mask) &&
- !cpu_isset(cpu, timer_bcast_ipi)) {
- disable_APIC_timer();
- cpu_set(cpu, timer_bcast_ipi);
+ /*
+ * Complain if the BIOS pretends there is one.
+ */
+ if (!cpu_has_apic &&
+ APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid])) {
+ printk(KERN_ERR "BIOS bug, local APIC #%d not detected!...\n",
+ boot_cpu_physical_apicid);
+ clear_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);
+ return -1;
}
-}
-EXPORT_SYMBOL(switch_APIC_timer_to_ipi);

-void switch_ipi_to_APIC_timer(void *cpumask)
-{
- cpumask_t mask = *(cpumask_t *)cpumask;
- int cpu = smp_processor_id();
+ verify_local_APIC();

- if (cpu_isset(cpu, mask) &&
- cpu_isset(cpu, timer_bcast_ipi)) {
- cpu_clear(cpu, timer_bcast_ipi);
- enable_APIC_timer();
- }
-}
-EXPORT_SYMBOL(switch_ipi_to_APIC_timer);
+ connect_bsp_APIC();

-#undef APIC_DIVISOR
+ /*
+ * Hack: In case of kdump, after a crash, kernel might be booting
+ * on a cpu with non-zero lapic id. But boot_cpu_physical_apicid
+ * might be zero if read from MP tables. Get it from LAPIC.
+ */
+#ifdef CONFIG_CRASH_DUMP
+ boot_cpu_physical_apicid = GET_APIC_ID(apic_read(APIC_ID));
+#endif
+ phys_cpu_present_map = physid_mask_of_physid(boot_cpu_physical_apicid);

-/*
- * Local timer interrupt handler. It does both profiling and
- * process statistics/rescheduling.
- *
- * We do profiling in every local tick, statistics/rescheduling
- * happen only every 'profiling multiplier' ticks. The default
- * multiplier is 1 and it can be changed by writing the new multiplier
- * value into /proc/profile.
- */
+ setup_local_APIC();

-inline void smp_local_timer_interrupt(void)
-{
- profile_tick(CPU_PROFILING);
-#ifdef CONFIG_SMP
- update_process_times(user_mode_vm(get_irq_regs()));
+#ifdef CONFIG_X86_IO_APIC
+ if (smp_found_config)
+ if (!skip_ioapic_setup && nr_ioapics)
+ setup_IO_APIC();
#endif
+ setup_boot_APIC_clock();

- /*
- * We take the 'long' return path, and there every subsystem
- * grabs the apropriate locks (kernel lock/ irq lock).
- *
- * we might want to decouple profiling from the 'long path',
- * and do the profiling totally in assembly.
- *
- * Currently this isn't too much of an issue (performance wise),
- * we can take more than 100K local irqs per second on a 100 MHz P5.
- */
+ return 0;
}

/*
- * Local APIC timer interrupt. This is the most natural way for doing
- * local interrupts, but local timer interrupts can be emulated by
- * broadcast interrupts too. [in case the hw doesn't support APIC timers]
- *
- * [ if a single-CPU system runs an SMP kernel then we call the local
- * interrupt as well. Thus we cannot inline the local irq ... ]
+ * APIC command line parameters
*/
-
-fastcall void smp_apic_timer_interrupt(struct pt_regs *regs)
-{
- struct pt_regs *old_regs = set_irq_regs(regs);
- int cpu = smp_processor_id();
-
- /*
- * the NMI deadlock-detector uses this.
- */
- per_cpu(irq_stat, cpu).apic_timer_irqs++;
-
- /*
- * NOTE! We'd better ACK the irq immediately,
- * because timer handling can be slow.
- */
- ack_APIC_irq();
- /*
- * update_process_times() expects us to have done irq_enter().
- * Besides, if we don't timer interrupts ignore the global
- * interrupt lock, which is the WrongThing (tm) to do.
- */
- irq_enter();
- smp_local_timer_interrupt();
- irq_exit();
- set_irq_regs(old_regs);
-}
-
-#ifndef CONFIG_SMP
-static void up_apic_timer_interrupt_call(void)
+static int __init parse_lapic(char *arg)
{
- int cpu = smp_processor_id();
-
- /*
- * the NMI deadlock-detector uses this.
- */
- per_cpu(irq_stat, cpu).apic_timer_irqs++;
-
- smp_local_timer_interrupt();
+ enable_local_apic = 1;
+ return 0;
}
-#endif
+early_param("lapic", parse_lapic);

-void smp_send_timer_broadcast_ipi(void)
+static int __init parse_nolapic(char *arg)
{
- cpumask_t mask;
-
- cpus_and(mask, cpu_online_map, timer_bcast_ipi);
- if (!cpus_empty(mask)) {
-#ifdef CONFIG_SMP
- send_IPI_mask(mask, LOCAL_TIMER_VECTOR);
-#else
- /*
- * We can directly call the apic timer interrupt handler
- * in UP case. Minus all irq related functions
- */
- up_apic_timer_interrupt_call();
-#endif
- }
+ enable_local_apic = -1;
+ clear_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);
+ return 0;
}
+early_param("nolapic", parse_nolapic);

-int setup_profiling_timer(unsigned int multiplier)
+static int __init apic_set_verbosity(char *str)
{
- return -EINVAL;
+ if (strcmp("debug", str) == 0)
+ apic_verbosity = APIC_DEBUG;
+ else if (strcmp("verbose", str) == 0)
+ apic_verbosity = APIC_VERBOSE;
+ return 1;
}

+__setup("apic=", apic_set_verbosity);
+
+
+/*
+ * Local APIC interrupts
+ */
+
/*
* This interrupt should _never_ happen with our APIC/SMP architecture
*/
@@ -1316,15 +1160,14 @@ fastcall void smp_spurious_interrupt(str
ack_APIC_irq();

/* see sw-dev-man vol 3, chapter 7.4.13.5 */
- printk(KERN_INFO "spurious APIC interrupt on CPU#%d, should never happen.\n",
- smp_processor_id());
+ printk(KERN_INFO "spurious APIC interrupt on CPU#%d, "
+ "should never happen.\n", smp_processor_id());
irq_exit();
}

/*
* This interrupt should never happen with our APIC/SMP architecture
*/
-
fastcall void smp_error_interrupt(struct pt_regs *regs)
{
unsigned long v, v1;
@@ -1348,69 +1191,261 @@ fastcall void smp_error_interrupt(struct
7: Illegal register address
*/
printk (KERN_DEBUG "APIC error on CPU%d: %02lx(%02lx)\n",
- smp_processor_id(), v , v1);
+ smp_processor_id(), v , v1);
irq_exit();
}

/*
- * This initializes the IO-APIC and APIC hardware if this is
- * a UP kernel.
+ * Initialize APIC interrupts
*/
-int __init APIC_init_uniprocessor (void)
+void __init apic_intr_init(void)
{
- if (enable_local_apic < 0)
- clear_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);
+#ifdef CONFIG_SMP
+ smp_intr_init();
+#endif
+ /* self generated IPI for local APIC timer */
+ set_intr_gate(LOCAL_TIMER_VECTOR, apic_timer_interrupt);

- if (!smp_found_config && !cpu_has_apic)
- return -1;
+ /* IPI vectors for APIC spurious and error interrupts */
+ set_intr_gate(SPURIOUS_APIC_VECTOR, spurious_interrupt);
+ set_intr_gate(ERROR_APIC_VECTOR, error_interrupt);

- /*
- * Complain if the BIOS pretends there is one.
- */
- if (!cpu_has_apic && APIC_INTEGRATED(apic_version[boot_cpu_physical_apicid])) {
- printk(KERN_ERR "BIOS bug, local APIC #%d not detected!...\n",
- boot_cpu_physical_apicid);
- clear_bit(X86_FEATURE_APIC, boot_cpu_data.x86_capability);
- return -1;
+ /* thermal monitor LVT interrupt */
+#ifdef CONFIG_X86_MCE_P4THERMAL
+ set_intr_gate(THERMAL_APIC_VECTOR, thermal_interrupt);
+#endif
+}
+
+/**
+ * connect_bsp_APIC - attach the APIC to the interrupt system
+ */
+void __init connect_bsp_APIC(void)
+{
+ if (pic_mode) {
+ /*
+ * Do not trust the local APIC being empty at bootup.
+ */
+ clear_local_APIC();
+ /*
+ * PIC mode, enable APIC mode in the IMCR, i.e. connect BSP's
+ * local APIC to INT and NMI lines.
+ */
+ apic_printk(APIC_VERBOSE, "leaving PIC mode, "
+ "enabling APIC mode.\n");
+ outb(0x70, 0x22);
+ outb(0x01, 0x23);
}
+ enable_apic_mode();
+}

- verify_local_APIC();
+/**
+ * disconnect_bsp_APIC - detach the APIC from the interrupt system
+ * @virt_wire_setup: indicates, whether virtual wire mode is selected
+ *
+ * Virtual wire mode is necessary to deliver legacy interrupts even when the
+ * APIC is disabled.
+ */
+void disconnect_bsp_APIC(int virt_wire_setup)
+{
+ if (pic_mode) {
+ /*
+ * Put the board back into PIC mode (has an effect only on
+ * certain older boards). Note that APIC interrupts, including
+ * IPIs, won't work beyond this point! The only exception are
+ * INIT IPIs.
+ */
+ apic_printk(APIC_VERBOSE, "disabling APIC mode, "
+ "entering PIC mode.\n");
+ outb(0x70, 0x22);
+ outb(0x00, 0x23);
+ } else {
+ /* Go back to Virtual Wire compatibility mode */
+ unsigned long value;

- connect_bsp_APIC();
+ /* For the spurious interrupt use vector F, and enable it */
+ value = apic_read(APIC_SPIV);
+ value &= ~APIC_VECTOR_MASK;
+ value |= APIC_SPIV_APIC_ENABLED;
+ value |= 0xf;
+ apic_write_around(APIC_SPIV, value);

- /*
- * Hack: In case of kdump, after a crash, kernel might be booting
- * on a cpu with non-zero lapic id. But boot_cpu_physical_apicid
- * might be zero if read from MP tables. Get it from LAPIC.
- */
-#ifdef CONFIG_CRASH_DUMP
- boot_cpu_physical_apicid = GET_APIC_ID(apic_read(APIC_ID));
-#endif
- phys_cpu_present_map = physid_mask_of_physid(boot_cpu_physical_apicid);
+ if (!virt_wire_setup) {
+ /*
+ * For LVT0 make it edge triggered, active high,
+ * external and enabled
+ */
+ value = apic_read(APIC_LVT0);
+ value &= ~(APIC_MODE_MASK | APIC_SEND_PENDING |
+ APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
+ APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED );
+ value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
+ value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_EXTINT);
+ apic_write_around(APIC_LVT0, value);
+ } else {
+ /* Disable LVT0 */
+ apic_write_around(APIC_LVT0, APIC_LVT_MASKED);
+ }

- setup_local_APIC();
+ /*
+ * For LVT1 make it edge triggered, active high, nmi and
+ * enabled
+ */
+ value = apic_read(APIC_LVT1);
+ value &= ~(
+ APIC_MODE_MASK | APIC_SEND_PENDING |
+ APIC_INPUT_POLARITY | APIC_LVT_REMOTE_IRR |
+ APIC_LVT_LEVEL_TRIGGER | APIC_LVT_MASKED);
+ value |= APIC_LVT_REMOTE_IRR | APIC_SEND_PENDING;
+ value = SET_APIC_DELIVERY_MODE(value, APIC_MODE_NMI);
+ apic_write_around(APIC_LVT1, value);
+ }
+}

-#ifdef CONFIG_X86_IO_APIC
- if (smp_found_config)
- if (!skip_ioapic_setup && nr_ioapics)
- setup_IO_APIC();
+/*
+ * Power management
+ */
+#ifdef CONFIG_PM
+
+static struct {
+ int active;
+ /* r/w apic fields */
+ unsigned int apic_id;
+ unsigned int apic_taskpri;
+ unsigned int apic_ldr;
+ unsigned int apic_dfr;
+ unsigned int apic_spiv;
+ unsigned int apic_lvtt;
+ unsigned int apic_lvtpc;
+ unsigned int apic_lvt0;
+ unsigned int apic_lvt1;
+ unsigned int apic_lvterr;
+ unsigned int apic_tmict;
+ unsigned int apic_tdcr;
+ unsigned int apic_thmr;
+} apic_pm_state;
+
+static int lapic_suspend(struct sys_device *dev, pm_message_t state)
+{
+ unsigned long flags;
+ int maxlvt;
+
+ if (!apic_pm_state.active)
+ return 0;
+
+ maxlvt = lapic_get_maxlvt();
+
+ apic_pm_state.apic_id = apic_read(APIC_ID);
+ apic_pm_state.apic_taskpri = apic_read(APIC_TASKPRI);
+ apic_pm_state.apic_ldr = apic_read(APIC_LDR);
+ apic_pm_state.apic_dfr = apic_read(APIC_DFR);
+ apic_pm_state.apic_spiv = apic_read(APIC_SPIV);
+ apic_pm_state.apic_lvtt = apic_read(APIC_LVTT);
+ if (maxlvt >= 4)
+ apic_pm_state.apic_lvtpc = apic_read(APIC_LVTPC);
+ apic_pm_state.apic_lvt0 = apic_read(APIC_LVT0);
+ apic_pm_state.apic_lvt1 = apic_read(APIC_LVT1);
+ apic_pm_state.apic_lvterr = apic_read(APIC_LVTERR);
+ apic_pm_state.apic_tmict = apic_read(APIC_TMICT);
+ apic_pm_state.apic_tdcr = apic_read(APIC_TDCR);
+#ifdef CONFIG_X86_MCE_P4THERMAL
+ if (maxlvt >= 5)
+ apic_pm_state.apic_thmr = apic_read(APIC_LVTTHMR);
#endif
- setup_boot_APIC_clock();

+ local_irq_save(flags);
+ disable_local_APIC();
+ local_irq_restore(flags);
return 0;
}

-static int __init parse_lapic(char *arg)
+static int lapic_resume(struct sys_device *dev)
{
- lapic_enable();
+ unsigned int l, h;
+ unsigned long flags;
+ int maxlvt;
+
+ if (!apic_pm_state.active)
+ return 0;
+
+ maxlvt = lapic_get_maxlvt();
+
+ local_irq_save(flags);
+
+ /*
+ * Make sure the APICBASE points to the right address
+ *
+ * FIXME! This will be wrong if we ever support suspend on
+ * SMP! We'll need to do this as part of the CPU restore!
+ */
+ rdmsr(MSR_IA32_APICBASE, l, h);
+ l &= ~MSR_IA32_APICBASE_BASE;
+ l |= MSR_IA32_APICBASE_ENABLE | mp_lapic_addr;
+ wrmsr(MSR_IA32_APICBASE, l, h);
+
+ apic_write(APIC_LVTERR, ERROR_APIC_VECTOR | APIC_LVT_MASKED);
+ apic_write(APIC_ID, apic_pm_state.apic_id);
+ apic_write(APIC_DFR, apic_pm_state.apic_dfr);
+ apic_write(APIC_LDR, apic_pm_state.apic_ldr);
+ apic_write(APIC_TASKPRI, apic_pm_state.apic_taskpri);
+ apic_write(APIC_SPIV, apic_pm_state.apic_spiv);
+ apic_write(APIC_LVT0, apic_pm_state.apic_lvt0);
+ apic_write(APIC_LVT1, apic_pm_state.apic_lvt1);
+#ifdef CONFIG_X86_MCE_P4THERMAL
+ if (maxlvt >= 5)
+ apic_write(APIC_LVTTHMR, apic_pm_state.apic_thmr);
+#endif
+ if (maxlvt >= 4)
+ apic_write(APIC_LVTPC, apic_pm_state.apic_lvtpc);
+ apic_write(APIC_LVTT, apic_pm_state.apic_lvtt);
+ apic_write(APIC_TDCR, apic_pm_state.apic_tdcr);
+ apic_write(APIC_TMICT, apic_pm_state.apic_tmict);
+ apic_write(APIC_ESR, 0);
+ apic_read(APIC_ESR);
+ apic_write(APIC_LVTERR, apic_pm_state.apic_lvterr);
+ apic_write(APIC_ESR, 0);
+ apic_read(APIC_ESR);
+ local_irq_restore(flags);
return 0;
}
-early_param("lapic", parse_lapic);

-static int __init parse_nolapic(char *arg)
+/*
+ * This device has no shutdown method - fully functioning local APICs
+ * are needed on every CPU up until machine_halt/restart/poweroff.
+ */
+
+static struct sysdev_class lapic_sysclass = {
+ set_kset_name("lapic"),
+ .resume = lapic_resume,
+ .suspend = lapic_suspend,
+};
+
+static struct sys_device device_lapic = {
+ .id = 0,
+ .cls = &lapic_sysclass,
+};
+
+static void __devinit apic_pm_activate(void)
{
- lapic_disable();
- return 0;
+ apic_pm_state.active = 1;
}
-early_param("nolapic", parse_nolapic);

+static int __init init_lapic_sysfs(void)
+{
+ int error;
+
+ if (!cpu_has_apic)
+ return 0;
+ /* XXX: remove suspend/resume procs if !apic_pm_state.active? */
+
+ error = sysdev_class_register(&lapic_sysclass);
+ if (!error)
+ error = sysdev_register(&device_lapic);
+ return error;
+}
+device_initcall(init_lapic_sysfs);
+
+#else /* CONFIG_PM */
+
+static void apic_pm_activate(void) { }
+
+#endif /* CONFIG_PM */
Index: linux/arch/i386/kernel/io_apic.c
===================================================================
--- linux.orig/arch/i386/kernel/io_apic.c
+++ linux/arch/i386/kernel/io_apic.c
@@ -1592,7 +1592,7 @@ void /*__init*/ print_local_APIC(void *
v = apic_read(APIC_LVR);
printk(KERN_INFO "... APIC VERSION: %08x\n", v);
ver = GET_APIC_VERSION(v);
- maxlvt = get_maxlvt();
+ maxlvt = lapic_get_maxlvt();

v = apic_read(APIC_TASKPRI);
printk(KERN_DEBUG "... APIC TASKPRI: %08x (%02x)\n", v, v & APIC_TPRI_MASK);
Index: linux/arch/i386/kernel/irq.c
===================================================================
--- linux.orig/arch/i386/kernel/irq.c
+++ linux/arch/i386/kernel/irq.c
@@ -10,7 +10,6 @@
* io_apic.c.)
*/

-#include <asm/uaccess.h>
#include <linux/module.h>
#include <linux/seq_file.h>
#include <linux/interrupt.h>
@@ -19,19 +18,34 @@
#include <linux/cpu.h>
#include <linux/delay.h>

+#include <asm/apic.h>
+#include <asm/uaccess.h>
+
DEFINE_PER_CPU(irq_cpustat_t, irq_stat) ____cacheline_internodealigned_in_smp;
EXPORT_PER_CPU_SYMBOL(irq_stat);

-#ifndef CONFIG_X86_LOCAL_APIC
/*
* 'what should we do if we get a hw irq event on an illegal vector'.
* each architecture has to answer this themselves.
*/
void ack_bad_irq(unsigned int irq)
{
- printk("unexpected IRQ trap at vector %02x\n", irq);
-}
+ printk(KERN_ERR "unexpected IRQ trap at vector %02x\n", irq);
+
+#ifdef CONFIG_X86_LOCAL_APIC
+ /*
+ * Currently unexpected vectors happen only on SMP and APIC.
+ * We _must_ ack these because every local APIC has only N
+ * irq slots per priority level, and a 'hanging, unacked' IRQ
+ * holds up an irq slot - in excessive cases (when multiple
+ * unexpected vectors occur) that might lock up the APIC
+ * completely.
+ * But only ack when the APIC is enabled -AK
+ */
+ if (cpu_has_apic)
+ ack_APIC_irq();
#endif
+}

#ifdef CONFIG_4KSTACKS
/*
Index: linux/arch/i386/kernel/smpboot.c
===================================================================
--- linux.orig/arch/i386/kernel/smpboot.c
+++ linux/arch/i386/kernel/smpboot.c
@@ -735,7 +735,7 @@ wakeup_secondary_cpu(int logical_apicid,
/*
* Due to the Pentium erratum 3AP.
*/
- maxlvt = get_maxlvt();
+ maxlvt = lapic_get_maxlvt();
if (maxlvt > 3) {
apic_read_around(APIC_SPIV);
apic_write(APIC_ESR, 0);
@@ -825,7 +825,7 @@ wakeup_secondary_cpu(int phys_apicid, un
*/
Dprintk("#startup loops: %d.\n", num_starts);

- maxlvt = get_maxlvt();
+ maxlvt = lapic_get_maxlvt();

for (j = 1; j <= num_starts; j++) {
Dprintk("Sending STARTUP #%d.\n",j);
Index: linux/include/asm-i386/apic.h
===================================================================
--- linux.orig/include/asm-i386/apic.h
+++ linux/include/asm-i386/apic.h
@@ -86,7 +86,7 @@ static inline void ack_APIC_irq(void)

extern void (*wait_timer_tick)(void);

-extern int get_maxlvt(void);
+extern int lapic_get_maxlvt(void);
extern void clear_local_APIC(void);
extern void connect_bsp_APIC (void);
extern void disconnect_bsp_APIC (int virt_wire_setup);

2006-11-19 08:00:06

by Andi Kleen

[permalink] [raw]
Subject: Re: [PATCH] Regard MSRs in lapic_suspend()/lapic_resume()

Karsten Wiese <[email protected]> writes:

> Read/Write APIC_LVTPC and APIC_LVTTHMR only,
> if get_maxlvt() returns certain values.
> This is done like everywhere else in i386/kernel/apic.c,
> so I guess its correct.
> Suspends/Resumes to disk fine and eleminates an smp_error_interrupt()
> here on a K8.

Added thanks.

I also ported it to x86-64

-Andi