linux-stable/arch/x86/kernel/acpi/sleep.c
Konrad Rzeszutek Wilk 357d122670 x86, xen, gdt: Remove the pvops variant of store_gdt.
The two use-cases where we needed to store the GDT were during ACPI S3 suspend
and resume. As the patches:
 x86/gdt/i386: store/load GDT for ACPI S3 or hibernation/resume path is not needed
 x86/gdt/64-bit: store/load GDT for ACPI S3 or hibernate/resume path is not needed.

have demonstrated - there are other mechanism by which the GDT is
saved and reloaded during early resume path.

Hence we do not need to worry about the pvops call-chain for saving the
GDT and can and can eliminate it. The other areas where the store_gdt is
used are never going to be hit when running under the pvops platforms.

Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Link: http://lkml.kernel.org/r/1365194544-14648-4-git-send-email-konrad.wilk@oracle.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
2013-04-11 15:40:38 -07:00

115 lines
3 KiB
C

/*
* sleep.c - x86-specific ACPI sleep support.
*
* Copyright (C) 2001-2003 Patrick Mochel
* Copyright (C) 2001-2003 Pavel Machek <pavel@ucw.cz>
*/
#include <linux/acpi.h>
#include <linux/bootmem.h>
#include <linux/memblock.h>
#include <linux/dmi.h>
#include <linux/cpumask.h>
#include <asm/segment.h>
#include <asm/desc.h>
#include <asm/pgtable.h>
#include <asm/cacheflush.h>
#include <asm/realmode.h>
#include "../../realmode/rm/wakeup.h"
#include "sleep.h"
unsigned long acpi_realmode_flags;
#if defined(CONFIG_SMP) && defined(CONFIG_64BIT)
static char temp_stack[4096];
#endif
/**
* acpi_suspend_lowlevel - save kernel state
*
* Create an identity mapped page table and copy the wakeup routine to
* low memory.
*/
int acpi_suspend_lowlevel(void)
{
struct wakeup_header *header =
(struct wakeup_header *) __va(real_mode_header->wakeup_header);
if (header->signature != WAKEUP_HEADER_SIGNATURE) {
printk(KERN_ERR "wakeup header does not match\n");
return -EINVAL;
}
header->video_mode = saved_video_mode;
header->pmode_behavior = 0;
#ifndef CONFIG_64BIT
native_store_gdt((struct desc_ptr *)&header->pmode_gdt);
if (!rdmsr_safe(MSR_EFER,
&header->pmode_efer_low,
&header->pmode_efer_high))
header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_EFER);
#endif /* !CONFIG_64BIT */
header->pmode_cr0 = read_cr0();
if (__this_cpu_read(cpu_info.cpuid_level) >= 0) {
header->pmode_cr4 = read_cr4();
header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_CR4);
}
if (!rdmsr_safe(MSR_IA32_MISC_ENABLE,
&header->pmode_misc_en_low,
&header->pmode_misc_en_high))
header->pmode_behavior |=
(1 << WAKEUP_BEHAVIOR_RESTORE_MISC_ENABLE);
header->realmode_flags = acpi_realmode_flags;
header->real_magic = 0x12345678;
#ifndef CONFIG_64BIT
header->pmode_entry = (u32)&wakeup_pmode_return;
header->pmode_cr3 = (u32)__pa_symbol(initial_page_table);
saved_magic = 0x12345678;
#else /* CONFIG_64BIT */
#ifdef CONFIG_SMP
stack_start = (unsigned long)temp_stack + sizeof(temp_stack);
early_gdt_descr.address =
(unsigned long)get_cpu_gdt_table(smp_processor_id());
initial_gs = per_cpu_offset(smp_processor_id());
#endif
initial_code = (unsigned long)wakeup_long64;
saved_magic = 0x123456789abcdef0L;
#endif /* CONFIG_64BIT */
do_suspend_lowlevel();
return 0;
}
static int __init acpi_sleep_setup(char *str)
{
while ((str != NULL) && (*str != '\0')) {
if (strncmp(str, "s3_bios", 7) == 0)
acpi_realmode_flags |= 1;
if (strncmp(str, "s3_mode", 7) == 0)
acpi_realmode_flags |= 2;
if (strncmp(str, "s3_beep", 7) == 0)
acpi_realmode_flags |= 4;
#ifdef CONFIG_HIBERNATION
if (strncmp(str, "s4_nohwsig", 10) == 0)
acpi_no_s4_hw_signature();
#endif
if (strncmp(str, "nonvs", 5) == 0)
acpi_nvs_nosave();
if (strncmp(str, "nonvs_s3", 8) == 0)
acpi_nvs_nosave_s3();
if (strncmp(str, "old_ordering", 12) == 0)
acpi_old_suspend_ordering();
str = strchr(str, ',');
if (str != NULL)
str += strspn(str, ", \t");
}
return 1;
}
__setup("acpi_sleep=", acpi_sleep_setup);