From: Felix Beck <[email protected]>
When the machine supports AP adapter interrupts polling will be
switched off at module initialization and the driver will work in
interrupt mode.
Signed-off-by: Felix Beck <[email protected]>
Signed-off-by: Martin Schwidefsky <[email protected]>
---
arch/s390/include/asm/isc.h | 1
drivers/s390/crypto/ap_bus.c | 174 ++++++++++++++++++++++++++++++++++++++++++-
drivers/s390/crypto/ap_bus.h | 6 +
3 files changed, 177 insertions(+), 4 deletions(-)
Index: quilt-2.6/arch/s390/include/asm/isc.h
===================================================================
--- quilt-2.6.orig/arch/s390/include/asm/isc.h
+++ quilt-2.6/arch/s390/include/asm/isc.h
@@ -17,6 +17,7 @@
#define CHSC_SCH_ISC 7 /* CHSC subchannels */
/* Adapter interrupts. */
#define QDIO_AIRQ_ISC IO_SCH_ISC /* I/O subchannel in qdio mode */
+#define AP_ISC 6 /* adjunct processor (crypto) devices */
/* Functions for registration of I/O interruption subclasses */
void isc_register(unsigned int isc);
Index: quilt-2.6/drivers/s390/crypto/ap_bus.c
===================================================================
--- quilt-2.6.orig/drivers/s390/crypto/ap_bus.c
+++ quilt-2.6/drivers/s390/crypto/ap_bus.c
@@ -5,6 +5,7 @@
* Author(s): Cornelia Huck <[email protected]>
* Martin Schwidefsky <[email protected]>
* Ralph Wuerthner <[email protected]>
+ * Felix Beck <[email protected]>
*
* Adjunct processor bus.
*
@@ -34,6 +35,10 @@
#include <linux/mutex.h>
#include <asm/s390_rdev.h>
#include <asm/reset.h>
+#include <asm/airq.h>
+#include <asm/atomic.h>
+#include <asm/system.h>
+#include <asm/isc.h>
#include <linux/hrtimer.h>
#include <linux/ktime.h>
@@ -46,6 +51,7 @@ static enum hrtimer_restart ap_poll_time
static int ap_poll_thread_start(void);
static void ap_poll_thread_stop(void);
static void ap_request_timeout(unsigned long);
+static inline void ap_schedule_poll_timer(void);
/*
* Module description.
@@ -80,19 +86,29 @@ static int ap_config_time = AP_CONFIG_TI
static DECLARE_WORK(ap_config_work, ap_scan_bus);
/*
- * Tasklet & timer for AP request polling.
+ * Tasklet & timer for AP request polling and interrupts
*/
static DECLARE_TASKLET(ap_tasklet, ap_poll_all, 0);
static atomic_t ap_poll_requests = ATOMIC_INIT(0);
static DECLARE_WAIT_QUEUE_HEAD(ap_poll_wait);
static struct task_struct *ap_poll_kthread = NULL;
static DEFINE_MUTEX(ap_poll_thread_mutex);
+static void *ap_interrupt_indicator;
static struct hrtimer ap_poll_timer;
/* In LPAR poll with 4kHz frequency. Poll every 250000 nanoseconds.
* If z/VM change to 1500000 nanoseconds to adjust to z/VM polling.*/
static unsigned long long poll_timeout = 250000;
/**
+ * ap_using_interrupts() - Returns non-zero if interrupt support is
+ * available.
+ */
+static inline int ap_using_interrupts(void)
+{
+ return ap_interrupt_indicator != NULL;
+}
+
+/**
* ap_intructions_available() - Test if AP instructions are available.
*
* Returns 0 if the AP instructions are installed.
@@ -113,6 +129,23 @@ static inline int ap_instructions_availa
}
/**
+ * ap_interrupts_available(): Test if AP interrupts are available.
+ *
+ * Returns 1 if AP interrupts are available.
+ */
+static int ap_interrupts_available(void)
+{
+ unsigned long long facility_bits[2];
+
+ if (stfle(facility_bits, 2) <= 1)
+ return 0;
+ if (!(facility_bits[0] & (1ULL << 61)) ||
+ !(facility_bits[1] & (1ULL << 62)))
+ return 0;
+ return 1;
+}
+
+/**
* ap_test_queue(): Test adjunct processor queue.
* @qid: The AP queue number
* @queue_depth: Pointer to queue depth value
@@ -152,6 +185,80 @@ static inline struct ap_queue_status ap_
return reg1;
}
+#ifdef CONFIG_64BIT
+/**
+ * ap_queue_interruption_control(): Enable interruption for a specific AP.
+ * @qid: The AP queue number
+ * @ind: The notification indicator byte
+ *
+ * Returns AP queue status.
+ */
+static inline struct ap_queue_status
+ap_queue_interruption_control(ap_qid_t qid, void *ind)
+{
+ register unsigned long reg0 asm ("0") = qid | 0x03000000UL;
+ register unsigned long reg1_in asm ("1") = 0x0000800000000000UL | AP_ISC;
+ register struct ap_queue_status reg1_out asm ("1");
+ register void *reg2 asm ("2") = ind;
+ asm volatile(
+ ".long 0xb2af0000" /* PQAP(RAPQ) */
+ : "+d" (reg0), "+d" (reg1_in), "=d" (reg1_out), "+d" (reg2)
+ :
+ : "cc" );
+ return reg1_out;
+}
+#endif
+
+/**
+ * ap_queue_enable_interruption(): Enable interruption on an AP.
+ * @qid: The AP queue number
+ * @ind: the notification indicator byte
+ *
+ * Enables interruption on AP queue via ap_queue_interruption_control(). Based
+ * on the return value it waits a while and tests the AP queue if interrupts
+ * have been switched on using ap_test_queue().
+ */
+static int ap_queue_enable_interruption(ap_qid_t qid, void *ind)
+{
+#ifdef CONFIG_64BIT
+ struct ap_queue_status status;
+ int t_depth, t_device_type, rc, i;
+
+ rc = -EBUSY;
+ status = ap_queue_interruption_control(qid, ind);
+
+ for (i = 0; i < AP_MAX_RESET; i++) {
+ switch (status.response_code) {
+ case AP_RESPONSE_NORMAL:
+ if (status.int_enabled)
+ return 0;
+ break;
+ case AP_RESPONSE_RESET_IN_PROGRESS:
+ case AP_RESPONSE_BUSY:
+ break;
+ case AP_RESPONSE_Q_NOT_AVAIL:
+ case AP_RESPONSE_DECONFIGURED:
+ case AP_RESPONSE_CHECKSTOPPED:
+ case AP_RESPONSE_INVALID_ADDRESS:
+ return -ENODEV;
+ case AP_RESPONSE_OTHERWISE_CHANGED:
+ if (status.int_enabled)
+ return 0;
+ break;
+ default:
+ break;
+ }
+ if (i < AP_MAX_RESET - 1) {
+ udelay(5);
+ status = ap_test_queue(qid, &t_depth, &t_device_type);
+ }
+ }
+ return rc;
+#else
+ return -EINVAL;
+#endif
+}
+
/**
* __ap_send(): Send message to adjunct processor queue.
* @qid: The AP queue number
@@ -295,6 +402,11 @@ static int ap_query_queue(ap_qid_t qid,
case AP_RESPONSE_CHECKSTOPPED:
rc = -ENODEV;
break;
+ case AP_RESPONSE_INVALID_ADDRESS:
+ rc = -ENODEV;
+ break;
+ case AP_RESPONSE_OTHERWISE_CHANGED:
+ break;
case AP_RESPONSE_BUSY:
break;
default:
@@ -345,6 +457,15 @@ static int ap_init_queue(ap_qid_t qid)
status = ap_test_queue(qid, &dummy, &dummy);
}
}
+ if (rc == 0 && ap_using_interrupts()) {
+ rc = ap_queue_enable_interruption(qid, ap_interrupt_indicator);
+ /* If interruption mode is supported by the machine,
+ * but an AP can not be enabled for interruption then
+ * the AP will be discarded. */
+ if (rc)
+ pr_err("Registering adapter interrupts for "
+ "AP %d failed\n", AP_QID_DEVICE(qid));
+ }
return rc;
}
@@ -599,6 +720,14 @@ static ssize_t ap_config_time_show(struc
return snprintf(buf, PAGE_SIZE, "%d\n", ap_config_time);
}
+static ssize_t ap_interrupts_show(struct bus_type *bus, char *buf)
+{
+ return snprintf(buf, PAGE_SIZE, "%d\n",
+ ap_using_interrupts() ? 1 : 0);
+}
+
+static BUS_ATTR(ap_interrupts, 0444, ap_interrupts_show, NULL);
+
static ssize_t ap_config_time_store(struct bus_type *bus,
const char *buf, size_t count)
{
@@ -653,7 +782,8 @@ static ssize_t poll_timeout_store(struct
ktime_t hr_time;
/* 120 seconds = maximum poll interval */
- if (sscanf(buf, "%llu\n", &time) != 1 || time < 1 || time > 120000000000)
+ if (sscanf(buf, "%llu\n", &time) != 1 || time < 1 ||
+ time > 120000000000ULL)
return -EINVAL;
poll_timeout = time;
hr_time = ktime_set(0, poll_timeout);
@@ -672,6 +802,7 @@ static struct bus_attribute *const ap_bu
&bus_attr_ap_domain,
&bus_attr_config_time,
&bus_attr_poll_thread,
+ &bus_attr_ap_interrupts,
&bus_attr_poll_timeout,
NULL,
};
@@ -814,6 +945,11 @@ out:
return rc;
}
+static void ap_interrupt_handler(void *unused1, void *unused2)
+{
+ tasklet_schedule(&ap_tasklet);
+}
+
/**
* __ap_scan_bus(): Scan the AP bus.
* @dev: Pointer to device
@@ -928,6 +1064,8 @@ ap_config_timeout(unsigned long ptr)
*/
static inline void ap_schedule_poll_timer(void)
{
+ if (ap_using_interrupts())
+ return;
if (hrtimer_is_queued(&ap_poll_timer))
return;
hrtimer_start(&ap_poll_timer, ktime_set(0, poll_timeout),
@@ -1207,6 +1345,12 @@ static void ap_poll_all(unsigned long du
unsigned long flags;
struct ap_device *ap_dev;
+ /* Reset the indicator if interrupts are used. Thus new interrupts can
+ * be received. Doing it in the beginning of the tasklet is therefor
+ * important that no requests on any AP get lost.
+ */
+ if (ap_using_interrupts())
+ xchg((u8 *)ap_interrupt_indicator, 0);
do {
flags = 0;
spin_lock(&ap_device_lock);
@@ -1268,6 +1412,8 @@ static int ap_poll_thread_start(void)
{
int rc;
+ if (ap_using_interrupts())
+ return 0;
mutex_lock(&ap_poll_thread_mutex);
if (!ap_poll_kthread) {
ap_poll_kthread = kthread_run(ap_poll_thread, NULL, "appoll");
@@ -1301,8 +1447,12 @@ static void ap_request_timeout(unsigned
{
struct ap_device *ap_dev = (struct ap_device *) data;
- if (ap_dev->reset == AP_RESET_ARMED)
+ if (ap_dev->reset == AP_RESET_ARMED) {
ap_dev->reset = AP_RESET_DO;
+
+ if (ap_using_interrupts())
+ tasklet_schedule(&ap_tasklet);
+ }
}
static void ap_reset_domain(void)
@@ -1345,6 +1495,16 @@ int __init ap_module_init(void)
printk(KERN_WARNING "AP instructions not installed.\n");
return -ENODEV;
}
+ if (ap_interrupts_available()) {
+ isc_register(AP_ISC);
+ ap_interrupt_indicator = s390_register_adapter_interrupt(
+ &ap_interrupt_handler, NULL, AP_ISC);
+ if (IS_ERR(ap_interrupt_indicator)) {
+ ap_interrupt_indicator = NULL;
+ isc_unregister(AP_ISC);
+ }
+ }
+
register_reset_call(&ap_reset_call);
/* Create /sys/bus/ap. */
@@ -1408,6 +1568,10 @@ out_bus:
bus_unregister(&ap_bus_type);
out:
unregister_reset_call(&ap_reset_call);
+ if (ap_using_interrupts()) {
+ s390_unregister_adapter_interrupt(ap_interrupt_indicator, AP_ISC);
+ isc_unregister(AP_ISC);
+ }
return rc;
}
@@ -1443,6 +1607,10 @@ void ap_module_exit(void)
bus_remove_file(&ap_bus_type, ap_bus_attrs[i]);
bus_unregister(&ap_bus_type);
unregister_reset_call(&ap_reset_call);
+ if (ap_using_interrupts()) {
+ s390_unregister_adapter_interrupt(ap_interrupt_indicator, AP_ISC);
+ isc_unregister(AP_ISC);
+ }
}
#ifndef CONFIG_ZCRYPT_MONOLITHIC
Index: quilt-2.6/drivers/s390/crypto/ap_bus.h
===================================================================
--- quilt-2.6.orig/drivers/s390/crypto/ap_bus.h
+++ quilt-2.6/drivers/s390/crypto/ap_bus.h
@@ -5,6 +5,7 @@
* Author(s): Cornelia Huck <[email protected]>
* Martin Schwidefsky <[email protected]>
* Ralph Wuerthner <[email protected]>
+ * Felix Beck <[email protected]>
*
* Adjunct processor bus header file.
*
@@ -67,7 +68,8 @@ struct ap_queue_status {
unsigned int queue_empty : 1;
unsigned int replies_waiting : 1;
unsigned int queue_full : 1;
- unsigned int pad1 : 5;
+ unsigned int pad1 : 4;
+ unsigned int int_enabled : 1;
unsigned int response_code : 8;
unsigned int pad2 : 16;
};
@@ -78,6 +80,8 @@ struct ap_queue_status {
#define AP_RESPONSE_DECONFIGURED 0x03
#define AP_RESPONSE_CHECKSTOPPED 0x04
#define AP_RESPONSE_BUSY 0x05
+#define AP_RESPONSE_INVALID_ADDRESS 0x06
+#define AP_RESPONSE_OTHERWISE_CHANGED 0x07
#define AP_RESPONSE_Q_FULL 0x10
#define AP_RESPONSE_NO_PENDING_REPLY 0x10
#define AP_RESPONSE_INDEX_TOO_BIG 0x11
--
blue skies,
Martin.
"Reality continues to ruin my life." - Calvin.