From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from az33egw02.freescale.net (az33egw02.freescale.net [192.88.158.103]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "az33egw02.freescale.net", Issuer "Thawte Premium Server CA" (verified OK)) by ozlabs.org (Postfix) with ESMTP id E35C3DDE17 for ; Wed, 24 Oct 2007 07:23:54 +1000 (EST) Date: Tue, 23 Oct 2007 16:24:04 -0500 From: Scott Wood To: paulus@samba.org Subject: [PATCH 1/7] Implement arch disable/enable irq hooks. Message-ID: <20071023212404.GA30942@loki.buserror.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: linuxppc-dev@ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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 --- Please queue these patches for 2.6.25 if they do not offend. arch/powerpc/kernel/time.c | 41 +++++++++++++++++++++++++++++++++++++++++ include/asm-powerpc/machdep.h | 13 +++++++++++++ 2 files changed, 54 insertions(+), 0 deletions(-) diff --git a/arch/powerpc/kernel/time.c b/arch/powerpc/kernel/time.c index 9eb3284..5e2a39b 100644 --- a/arch/powerpc/kernel/time.c +++ b/arch/powerpc/kernel/time.c @@ -647,6 +647,47 @@ void wakeup_decrementer(void) set_dec(ticks); } +#ifdef CONFIG_SUSPEND +void generic_suspend_disable_irqs(void) +{ + preempt_disable(); + + /* Disable the decrementer, so that it doesn't interfere + * with suspending. + */ + + set_dec(0x7fffffff); + hard_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 6968f43..15ba15a 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_SUSPEND + /* 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); @@ -326,5 +336,8 @@ static inline void log_error(char *buf, unsigned int err_type, int fatal) ppc_md.log_error(buf, err_type, fatal); } +void generic_suspend_disable_irqs(void); +void generic_suspend_enable_irqs(void); + #endif /* __KERNEL__ */ #endif /* _ASM_POWERPC_MACHDEP_H */ -- 1.5.3.4