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 <[EMAIL PROTECTED]>
---
Paul, please apply this series for 2.6.25 if all is well.
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 a925a8e..509f481 100644
--- a/arch/powerpc/kernel/time.c
+++ b/arch/powerpc/kernel/time.c
@@ -623,6 +623,47 @@ 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();
+
+ hard_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 */
--
1.5.3.7
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