Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit cd74257b authored by Konrad Rzeszutek Wilk's avatar Konrad Rzeszutek Wilk Committed by H. Peter Anvin
Browse files

x86, acpi: Call acpi_enter_sleep_state via an asmlinkage C function from assembler 



With commit a2ef5c4f
"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

Reviewed-by: default avatarH. Peter Anvin <hpa@zytor.com>
Suggested-by: default avatarH. Peter Anvin <hpa@zytor.com>
[v2: Remove extra assembler operations, per hpa review]
Signed-off-by: default avatarKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Link: http://lkml.kernel.org/r/1335150198-21899-3-git-send-email-konrad.wilk@oracle.com


Signed-off-by: default avatarH. Peter Anvin <hpa@linux.intel.com>
parent 2a14e541

arch/x86/kernel/acpi/sleep.c

+4 −0
Original line number Diff line number Diff line
@@ -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

 *

arch/x86/kernel/acpi/sleep.h

+2 −0
Original line number Diff line number Diff line
@@ -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);

arch/x86/kernel/acpi/wakeup_32.S

+1 −3
Original line number Diff line number Diff line
@@ -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

arch/x86/kernel/acpi/wakeup_64.S

+1 −3
Original line number Diff line number Diff line
@@ -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