2021-03-07 02:30:31

by Guo Ren

[permalink] [raw]
Subject: [PATCH 1/2] csky: Enable generic clockevent broadcast

From: Guo Ren <[email protected]>

When percpu-timers are stopped by deep power saving mode, we need
system timer help to broadcast IPI_TIMER.

This is first introduced by broken x86 hardware, where the local apic
timer stops in C3 state. But many other architectures(powerpc, mips,
arm, hexagon, openrisc, sh) have supported the infrastructure to
deal with Power Management issues.

Signed-off-by: Guo Ren <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Daniel Lezcano <[email protected]>
---
arch/csky/Kconfig | 2 ++
arch/csky/kernel/smp.c | 17 +++++++++++++++++
2 files changed, 19 insertions(+)

diff --git a/arch/csky/Kconfig b/arch/csky/Kconfig
index 34e91224adc3..4328511ac050 100644
--- a/arch/csky/Kconfig
+++ b/arch/csky/Kconfig
@@ -6,6 +6,7 @@ config CSKY
select ARCH_HAS_GCOV_PROFILE_ALL
select ARCH_HAS_SYNC_DMA_FOR_CPU
select ARCH_HAS_SYNC_DMA_FOR_DEVICE
+ select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
select ARCH_USE_BUILTIN_BSWAP
select ARCH_USE_QUEUED_RWLOCKS
select ARCH_WANT_FRAME_POINTERS if !CPU_CK610
@@ -19,6 +20,7 @@ config CSKY
select IRQ_DOMAIN
select HANDLE_DOMAIN_IRQ
select DW_APB_TIMER_OF
+ select GENERIC_CLOCKEVENTS_BROADCAST if SMP
select GENERIC_IOREMAP
select GENERIC_LIB_ASHLDI3
select GENERIC_LIB_ASHRDI3
diff --git a/arch/csky/kernel/smp.c b/arch/csky/kernel/smp.c
index 0f9f5eef9338..76d38d84da70 100644
--- a/arch/csky/kernel/smp.c
+++ b/arch/csky/kernel/smp.c
@@ -8,6 +8,7 @@
#include <linux/kernel_stat.h>
#include <linux/notifier.h>
#include <linux/cpu.h>
+#include <linux/clockchips.h>
#include <linux/percpu.h>
#include <linux/delay.h>
#include <linux/err.h>
@@ -32,6 +33,7 @@ enum ipi_message_type {
IPI_RESCHEDULE,
IPI_CALL_FUNC,
IPI_IRQ_WORK,
+ IPI_TIMER,
IPI_MAX
};

@@ -67,6 +69,13 @@ static irqreturn_t handle_ipi(int irq, void *dev)
irq_work_run();
}

+#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
+ if (ops & (1 << IPI_TIMER)) {
+ stats[IPI_TIMER]++;
+ tick_receive_broadcast();
+ }
+#endif
+
BUG_ON((ops >> IPI_MAX) != 0);
}

@@ -102,6 +111,7 @@ static const char * const ipi_names[] = {
[IPI_RESCHEDULE] = "Rescheduling interrupts",
[IPI_CALL_FUNC] = "Function call interrupts",
[IPI_IRQ_WORK] = "Irq work interrupts",
+ [IPI_TIMER] = "Timer broadcast interrupts",
};

int arch_show_interrupts(struct seq_file *p, int prec)
@@ -130,6 +140,13 @@ void arch_send_call_function_single_ipi(int cpu)
send_ipi_message(cpumask_of(cpu), IPI_CALL_FUNC);
}

+#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
+void tick_broadcast(const struct cpumask *mask)
+{
+ send_ipi_message(mask, IPI_TIMER);
+}
+#endif
+
static void ipi_stop(void *unused)
{
while (1);
--
2.25.1


2021-03-07 02:30:42

by Guo Ren

[permalink] [raw]
Subject: [PATCH 2/2] riscv: Enable generic clockevent broadcast

From: Guo Ren <[email protected]>

When percpu-timers are stopped by deep power saving mode, we
need system timer help to broadcast IPI_TIMER.

This is first introduced by broken x86 hardware, where the local apic
timer stops in C3 state. But many other architectures(powerpc, mips,
arm, hexagon, openrisc, sh) have supported the infrastructure to
deal with Power Management issues.

Signed-off-by: Guo Ren <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Daniel Lezcano <[email protected]>
Cc: Anup Patel <[email protected]>
Cc: Atish Patra <[email protected]>
Cc: Palmer Dabbelt <[email protected]>
Cc: Greentime Hu <[email protected]>
---
arch/riscv/Kconfig | 2 ++
arch/riscv/kernel/smp.c | 16 ++++++++++++++++
2 files changed, 18 insertions(+)

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index 85d626b8ce5e..8637e7344abe 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -28,6 +28,7 @@ config RISCV
select ARCH_HAS_SET_DIRECT_MAP
select ARCH_HAS_SET_MEMORY
select ARCH_HAS_STRICT_KERNEL_RWX if MMU
+ select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT
select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
@@ -39,6 +40,7 @@ config RISCV
select EDAC_SUPPORT
select GENERIC_ARCH_TOPOLOGY if SMP
select GENERIC_ATOMIC64 if !64BIT
+ select GENERIC_CLOCKEVENTS_BROADCAST if SMP
select GENERIC_EARLY_IOREMAP
select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO
select GENERIC_IOREMAP
diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c
index ea028d9e0d24..8325d33411d8 100644
--- a/arch/riscv/kernel/smp.c
+++ b/arch/riscv/kernel/smp.c
@@ -9,6 +9,7 @@
*/

#include <linux/cpu.h>
+#include <linux/clockchips.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/profile.h>
@@ -27,6 +28,7 @@ enum ipi_message_type {
IPI_CALL_FUNC,
IPI_CPU_STOP,
IPI_IRQ_WORK,
+ IPI_TIMER,
IPI_MAX
};

@@ -176,6 +178,12 @@ void handle_IPI(struct pt_regs *regs)
irq_work_run();
}

+#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
+ if (ops & (1 << IPI_TIMER)) {
+ stats[IPI_TIMER]++;
+ tick_receive_broadcast();
+ }
+#endif
BUG_ON((ops >> IPI_MAX) != 0);

/* Order data access and bit testing. */
@@ -192,6 +200,7 @@ static const char * const ipi_names[] = {
[IPI_CALL_FUNC] = "Function call interrupts",
[IPI_CPU_STOP] = "CPU stop interrupts",
[IPI_IRQ_WORK] = "IRQ work interrupts",
+ [IPI_TIMER] = "Timer broadcast interrupts",
};

void show_ipi_stats(struct seq_file *p, int prec)
@@ -217,6 +226,13 @@ void arch_send_call_function_single_ipi(int cpu)
send_ipi_single(cpu, IPI_CALL_FUNC);
}

+#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
+void tick_broadcast(const struct cpumask *mask)
+{
+ send_ipi_mask(mask, IPI_TIMER);
+}
+#endif
+
void smp_send_stop(void)
{
unsigned long timeout;
--
2.25.1

2021-03-07 03:52:38

by Anup Patel

[permalink] [raw]
Subject: Re: [PATCH 2/2] riscv: Enable generic clockevent broadcast

On Sun, Mar 7, 2021 at 7:55 AM <[email protected]> wrote:
>
> From: Guo Ren <[email protected]>
>
> When percpu-timers are stopped by deep power saving mode, we
> need system timer help to broadcast IPI_TIMER.
>
> This is first introduced by broken x86 hardware, where the local apic
> timer stops in C3 state. But many other architectures(powerpc, mips,
> arm, hexagon, openrisc, sh) have supported the infrastructure to
> deal with Power Management issues.
>
> Signed-off-by: Guo Ren <[email protected]>
> Cc: Arnd Bergmann <[email protected]>
> Cc: Thomas Gleixner <[email protected]>
> Cc: Daniel Lezcano <[email protected]>
> Cc: Anup Patel <[email protected]>
> Cc: Atish Patra <[email protected]>
> Cc: Palmer Dabbelt <[email protected]>
> Cc: Greentime Hu <[email protected]>

Looks good to me.

Reviewed-by: Anup Patel <[email protected]>

Regards,
Anup

> ---
> arch/riscv/Kconfig | 2 ++
> arch/riscv/kernel/smp.c | 16 ++++++++++++++++
> 2 files changed, 18 insertions(+)
>
> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> index 85d626b8ce5e..8637e7344abe 100644
> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -28,6 +28,7 @@ config RISCV
> select ARCH_HAS_SET_DIRECT_MAP
> select ARCH_HAS_SET_MEMORY
> select ARCH_HAS_STRICT_KERNEL_RWX if MMU
> + select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
> select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
> select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT
> select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
> @@ -39,6 +40,7 @@ config RISCV
> select EDAC_SUPPORT
> select GENERIC_ARCH_TOPOLOGY if SMP
> select GENERIC_ATOMIC64 if !64BIT
> + select GENERIC_CLOCKEVENTS_BROADCAST if SMP
> select GENERIC_EARLY_IOREMAP
> select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO
> select GENERIC_IOREMAP
> diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c
> index ea028d9e0d24..8325d33411d8 100644
> --- a/arch/riscv/kernel/smp.c
> +++ b/arch/riscv/kernel/smp.c
> @@ -9,6 +9,7 @@
> */
>
> #include <linux/cpu.h>
> +#include <linux/clockchips.h>
> #include <linux/interrupt.h>
> #include <linux/module.h>
> #include <linux/profile.h>
> @@ -27,6 +28,7 @@ enum ipi_message_type {
> IPI_CALL_FUNC,
> IPI_CPU_STOP,
> IPI_IRQ_WORK,
> + IPI_TIMER,
> IPI_MAX
> };
>
> @@ -176,6 +178,12 @@ void handle_IPI(struct pt_regs *regs)
> irq_work_run();
> }
>
> +#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
> + if (ops & (1 << IPI_TIMER)) {
> + stats[IPI_TIMER]++;
> + tick_receive_broadcast();
> + }
> +#endif
> BUG_ON((ops >> IPI_MAX) != 0);
>
> /* Order data access and bit testing. */
> @@ -192,6 +200,7 @@ static const char * const ipi_names[] = {
> [IPI_CALL_FUNC] = "Function call interrupts",
> [IPI_CPU_STOP] = "CPU stop interrupts",
> [IPI_IRQ_WORK] = "IRQ work interrupts",
> + [IPI_TIMER] = "Timer broadcast interrupts",
> };
>
> void show_ipi_stats(struct seq_file *p, int prec)
> @@ -217,6 +226,13 @@ void arch_send_call_function_single_ipi(int cpu)
> send_ipi_single(cpu, IPI_CALL_FUNC);
> }
>
> +#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
> +void tick_broadcast(const struct cpumask *mask)
> +{
> + send_ipi_mask(mask, IPI_TIMER);
> +}
> +#endif
> +
> void smp_send_stop(void)
> {
> unsigned long timeout;
> --
> 2.25.1
>
>
> _______________________________________________
> linux-riscv mailing list
> [email protected]
> http://lists.infradead.org/mailman/listinfo/linux-riscv

2021-03-17 03:42:35

by Palmer Dabbelt

[permalink] [raw]
Subject: Re: [PATCH 2/2] riscv: Enable generic clockevent broadcast

On Sat, 06 Mar 2021 18:24:46 PST (-0800), [email protected] wrote:
> From: Guo Ren <[email protected]>
>
> When percpu-timers are stopped by deep power saving mode, we
> need system timer help to broadcast IPI_TIMER.
>
> This is first introduced by broken x86 hardware, where the local apic
> timer stops in C3 state. But many other architectures(powerpc, mips,
> arm, hexagon, openrisc, sh) have supported the infrastructure to
> deal with Power Management issues.
>
> Signed-off-by: Guo Ren <[email protected]>
> Cc: Arnd Bergmann <[email protected]>
> Cc: Thomas Gleixner <[email protected]>
> Cc: Daniel Lezcano <[email protected]>
> Cc: Anup Patel <[email protected]>
> Cc: Atish Patra <[email protected]>
> Cc: Palmer Dabbelt <[email protected]>
> Cc: Greentime Hu <[email protected]>
> ---
> arch/riscv/Kconfig | 2 ++
> arch/riscv/kernel/smp.c | 16 ++++++++++++++++
> 2 files changed, 18 insertions(+)
>
> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> index 85d626b8ce5e..8637e7344abe 100644
> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -28,6 +28,7 @@ config RISCV
> select ARCH_HAS_SET_DIRECT_MAP
> select ARCH_HAS_SET_MEMORY
> select ARCH_HAS_STRICT_KERNEL_RWX if MMU
> + select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
> select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
> select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT
> select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
> @@ -39,6 +40,7 @@ config RISCV
> select EDAC_SUPPORT
> select GENERIC_ARCH_TOPOLOGY if SMP
> select GENERIC_ATOMIC64 if !64BIT
> + select GENERIC_CLOCKEVENTS_BROADCAST if SMP
> select GENERIC_EARLY_IOREMAP
> select GENERIC_GETTIMEOFDAY if HAVE_GENERIC_VDSO
> select GENERIC_IOREMAP
> diff --git a/arch/riscv/kernel/smp.c b/arch/riscv/kernel/smp.c
> index ea028d9e0d24..8325d33411d8 100644
> --- a/arch/riscv/kernel/smp.c
> +++ b/arch/riscv/kernel/smp.c
> @@ -9,6 +9,7 @@
> */
>
> #include <linux/cpu.h>
> +#include <linux/clockchips.h>
> #include <linux/interrupt.h>
> #include <linux/module.h>
> #include <linux/profile.h>
> @@ -27,6 +28,7 @@ enum ipi_message_type {
> IPI_CALL_FUNC,
> IPI_CPU_STOP,
> IPI_IRQ_WORK,
> + IPI_TIMER,
> IPI_MAX
> };
>
> @@ -176,6 +178,12 @@ void handle_IPI(struct pt_regs *regs)
> irq_work_run();
> }
>
> +#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
> + if (ops & (1 << IPI_TIMER)) {
> + stats[IPI_TIMER]++;
> + tick_receive_broadcast();
> + }
> +#endif
> BUG_ON((ops >> IPI_MAX) != 0);
>
> /* Order data access and bit testing. */
> @@ -192,6 +200,7 @@ static const char * const ipi_names[] = {
> [IPI_CALL_FUNC] = "Function call interrupts",
> [IPI_CPU_STOP] = "CPU stop interrupts",
> [IPI_IRQ_WORK] = "IRQ work interrupts",
> + [IPI_TIMER] = "Timer broadcast interrupts",
> };
>
> void show_ipi_stats(struct seq_file *p, int prec)
> @@ -217,6 +226,13 @@ void arch_send_call_function_single_ipi(int cpu)
> send_ipi_single(cpu, IPI_CALL_FUNC);
> }
>
> +#ifdef CONFIG_GENERIC_CLOCKEVENTS_BROADCAST
> +void tick_broadcast(const struct cpumask *mask)
> +{
> + send_ipi_mask(mask, IPI_TIMER);
> +}
> +#endif
> +
> void smp_send_stop(void)
> {
> unsigned long timeout;

Thanks, this is on for-next.

2021-03-17 09:18:16

by Daniel Lezcano

[permalink] [raw]
Subject: Re: [PATCH 1/2] csky: Enable generic clockevent broadcast

On 07/03/2021 03:24, [email protected] wrote:
> From: Guo Ren <[email protected]>
>
> When percpu-timers are stopped by deep power saving mode, we need
> system timer help to broadcast IPI_TIMER.
>
> This is first introduced by broken x86 hardware, where the local apic
> timer stops in C3 state. But many other architectures(powerpc, mips,
> arm, hexagon, openrisc, sh) have supported the infrastructure to
> deal with Power Management issues.
>
> Signed-off-by: Guo Ren <[email protected]>
> Cc: Arnd Bergmann <[email protected]>
> Cc: Thomas Gleixner <[email protected]>
> Cc: Daniel Lezcano <[email protected]>
> ---

Acked-by: Daniel Lezcano <[email protected]>


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