[PATCH 2/4] Implement arch disable/enable irq hooks.
From: Scott Wood <hidden>
Date: 2007-07-12 19:13:05
Subsystem:
linux for powerpc (32-bit and 64-bit), the rest · Maintainers:
Madhavan Srinivasan, Linus Torvalds
These hooks ensure that a decrementer interrupt is not pending when suspending; otherwise, problems may occur. For example, with deep sleep on the 831x, a pending decrementer will cause a system freeze because the SoC thinks the decrementer interrupt would have woken the system, but the core must have interrupts disabled due to the setup required for deep sleep. Signed-off-by: Scott Wood <redacted> --- arch/powerpc/kernel/time.c | 41 +++++++++++++++++++++++++++++++++++++++++ include/asm-powerpc/machdep.h | 10 ++++++++++ 2 files changed, 51 insertions(+), 0 deletions(-)
diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c
index e5df167..253f46d 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c@@ -728,6 +728,47 @@ void wakeup_decrementer(void) set_dec(ticks); } +#ifdef CONFIG_PM +void generic_suspend_disable_irqs(void) +{ + preempt_disable(); + + /* Disable the decrementer, so that it doesn't interfere + * with suspending. + */ + + set_dec(0x7fffffff); + local_irq_disable(); + set_dec(0x7fffffff); +} + +void generic_suspend_enable_irqs(void) +{ + wakeup_decrementer(); + + local_irq_enable(); + preempt_enable(); +} + +/* Overrides the weak version in kernel/power/main.c */ +void arch_suspend_disable_irqs(void) +{ + if (ppc_md.suspend_disable_irqs) + ppc_md.suspend_disable_irqs(); + else + generic_suspend_disable_irqs(); +} + +/* Overrides the weak version in kernel/power/main.c */ +void arch_suspend_enable_irqs(void) +{ + if (ppc_md.suspend_enable_irqs) + ppc_md.suspend_enable_irqs(); + else + generic_suspend_enable_irqs(); +} +#endif + #ifdef CONFIG_SMP void __init smp_space_timers(unsigned int max_cpus) {
diff --git a/include/asm-powerpc/machdep.h b/include/asm-powerpc/machdep.h
index 71c6e7e..492ecf3 100644
--- a/include/asm-powerpc/machdep.h
+++ b/include/asm-powerpc/machdep.h@@ -253,6 +253,16 @@ struct machdep_calls { */ void (*machine_kexec)(struct kimage *image); #endif /* CONFIG_KEXEC */ + +#ifdef CONFIG_PM + /* These are called to disable and enable, respectively, IRQs when + * entering a suspend state. If NULL, then the generic versions + * will be called. The generic versions disable/enable the + * decrementer along with interrupts. + */ + void (*suspend_disable_irqs)(void); + void (*suspend_enable_irqs)(void); +#endif }; extern void power4_idle(void);
--
1.5.0.3