On Wednesday, April 18, 2012, Konrad Rzeszutek Wilk wrote:
> With commit a2ef5c4fd44ce3922435139393b89f2cce47f576
> "ACPI: Move module parameter gts and bfs to sleep.c" the
> wake_sleep_flags is required when calling acpi_enter_sleep_state.
>
> The assembler code in wakeup_*.S did not do that. One solution
> is to call it from assembler and stick the wake_sleep_flags on
> the stack (for 32-bit) or in %esi (for 64-bit). hpa and rafael
> both suggested however to create a wrapper function to call
> acpi_enter_sleep_state and call said wrapper function
> ("acpi_enter_s3") from assembler.
>
> For 32-bit, the acpi_enter_s3 ends up looking as so:
>
> push %ebp
> mov %esp,%ebp
> sub $0x8,%esp
> movzbl 0xc1809314,%eax [wake_sleep_flags]
> movl $0x3,(%esp)
> mov %eax,0x4(%esp)
> call 0xc12d1fa0 <acpi_enter_sleep_state>
> leave
> ret
>
> And 64-bit:
>
> movzbl 0x9afde1(%rip),%esi [wake_sleep_flags]
> push %rbp
> mov $0x3,%edi
> mov %rsp,%rbp
> callq 0xffffffff812e9800 <acpi_enter_sleep_state>
> leaveq
> retq
>
> Suggested-by: H. Peter Anvin <hpa@xxxxxxxxx>
> [v2: Remove extra assembler operations, per hpa review]
> Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
Acked-by: Rafael J. Wysocki <rjw@xxxxxxx>
> ---
> arch/x86/kernel/acpi/sleep.c | 4 ++++
> arch/x86/kernel/acpi/sleep.h | 2 ++
> arch/x86/kernel/acpi/wakeup_32.S | 4 +---
> arch/x86/kernel/acpi/wakeup_64.S | 4 +---
> 4 files changed, 8 insertions(+), 6 deletions(-)
>
> diff --git a/arch/x86/kernel/acpi/sleep.c b/arch/x86/kernel/acpi/sleep.c
> index 103b6ab..146a49c 100644
> --- a/arch/x86/kernel/acpi/sleep.c
> +++ b/arch/x86/kernel/acpi/sleep.c
> @@ -24,6 +24,10 @@ unsigned long acpi_realmode_flags;
> static char temp_stack[4096];
> #endif
>
> +asmlinkage void acpi_enter_s3(void)
> +{
> + acpi_enter_sleep_state(3, wake_sleep_flags);
> +}
> /**
> * acpi_suspend_lowlevel - save kernel state
> *
> diff --git a/arch/x86/kernel/acpi/sleep.h b/arch/x86/kernel/acpi/sleep.h
> index fe5fdda..d68677a 100644
> --- a/arch/x86/kernel/acpi/sleep.h
> +++ b/arch/x86/kernel/acpi/sleep.h
> @@ -3,6 +3,7 @@
> */
>
> #include <asm/trampoline.h>
> +#include <linux/linkage.h>
>
> extern unsigned long saved_video_mode;
> extern long saved_magic;
> @@ -10,6 +11,7 @@ extern long saved_magic;
> extern int wakeup_pmode_return;
>
> extern u8 wake_sleep_flags;
> +extern asmlinkage void acpi_enter_s3(void);
>
> extern unsigned long acpi_copy_wakeup_routine(unsigned long);
> extern void wakeup_long64(void);
> diff --git a/arch/x86/kernel/acpi/wakeup_32.S b/arch/x86/kernel/acpi/wakeup_32.S
> index 13ab720..7261083 100644
> --- a/arch/x86/kernel/acpi/wakeup_32.S
> +++ b/arch/x86/kernel/acpi/wakeup_32.S
> @@ -74,9 +74,7 @@ restore_registers:
> ENTRY(do_suspend_lowlevel)
> call save_processor_state
> call save_registers
> - pushl $3
> - call acpi_enter_sleep_state
> - addl $4, %esp
> + call acpi_enter_s3
>
> # In case of S3 failure, we'll emerge here. Jump
> # to ret_point to recover
> diff --git a/arch/x86/kernel/acpi/wakeup_64.S b/arch/x86/kernel/acpi/wakeup_64.S
> index 8ea5164..014d1d2 100644
> --- a/arch/x86/kernel/acpi/wakeup_64.S
> +++ b/arch/x86/kernel/acpi/wakeup_64.S
> @@ -71,9 +71,7 @@ ENTRY(do_suspend_lowlevel)
> movq %rsi, saved_rsi
>
> addq $8, %rsp
> - movl $3, %edi
> - xorl %eax, %eax
> - call acpi_enter_sleep_state
> + call acpi_enter_s3
> /* in case something went wrong, restore the machine status and go on */
> jmp resume_point
>
>
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