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/*
* Suspend support specific for i386.
*
* Distribute under GPLv2
*
* Copyright (c) 2002 Pavel Machek <pavel@suse.cz>
* Copyright (c) 2001 Patrick Mochel <mochel@osdl.org>
*/
#include <linux/config.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/spinlock.h>
#include <linux/poll.h>
#include <linux/delay.h>
#include <linux/sysrq.h>
#include <linux/proc_fs.h>
#include <linux/irq.h>
#include <linux/pm.h>
#include <linux/device.h>
#include <linux/suspend.h>
#include <linux/acpi.h>
#include <asm/uaccess.h>
#include <asm/acpi.h>
#include <asm/tlbflush.h>
#include <asm/processor.h>
static struct saved_context saved_context;
unsigned long saved_context_ebx;
unsigned long saved_context_esp, saved_context_ebp;
unsigned long saved_context_esi, saved_context_edi;
unsigned long saved_context_eflags;
void __save_processor_state(struct saved_context *ctxt)
{
kernel_fpu_begin();
/*
* descriptor tables
*/
asm volatile ("sgdt %0" : "=m" (ctxt->gdt_limit));
asm volatile ("sidt %0" : "=m" (ctxt->idt_limit));
asm volatile ("str %0" : "=m" (ctxt->tr));
/*
* segment registers
*/
asm volatile ("movw %%es, %0" : "=m" (ctxt->es));
asm volatile ("movw %%fs, %0" : "=m" (ctxt->fs));
asm volatile ("movw %%gs, %0" : "=m" (ctxt->gs));
asm volatile ("movw %%ss, %0" : "=m" (ctxt->ss));
/*
* control registers
*/
ctxt->cr0 = read_cr0();
ctxt->cr2 = read_cr2();
ctxt->cr3 = read_cr3();
ctxt->cr4 = read_cr4();
}
void save_processor_state(void)
{
__save_processor_state(&saved_context);
}
static void
do_fpu_end(void)
{
/* restore FPU regs if necessary */
/* Do it out of line so that gcc does not move cr0 load to some stupid place */
kernel_fpu_end();
mxcsr_feature_mask_init();
}
static void fix_processor_context(void)
{
int cpu = smp_processor_id();
struct tss_struct * t = &per_cpu(init_tss, cpu);
set_tss_desc(cpu,t); /* This just modifies memory; should not be necessary. But... This is necessary, because 386 hardware has concept of busy TSS or some similar stupidity. */
per_cpu(cpu_gdt_table, cpu)[GDT_ENTRY_TSS].b &= 0xfffffdff;
load_TR_desc(); /* This does ltr */
load_LDT(¤t->active_mm->context); /* This does lldt */
/*
* Now maybe reload the debug registers
*/
if (current->thread.debugreg[7]){
set_debugreg(current->thread.debugreg[0], 0);
set_debugreg(current->thread.debugreg[1], 1);
set_debugreg(current->thread.debugreg[2], 2);
set_debugreg(current->thread.debugreg[3], 3);
/* no 4 and 5 */
set_debugreg(current->thread.debugreg[6], 6);
set_debugreg(current->thread.debugreg[7], 7);
}
}
void __restore_processor_state(struct saved_context *ctxt)
{
/*
* control registers
*/
write_cr4(ctxt->cr4);
write_cr3(ctxt->cr3);
write_cr2(ctxt->cr2);
write_cr2(ctxt->cr0);
/*
* now restore the descriptor tables to their proper values
* ltr is done i fix_processor_context().
*/
asm volatile ("lgdt %0" :: "m" (ctxt->gdt_limit));
asm volatile ("lidt %0" :: "m" (ctxt->idt_limit));
/*
* segment registers
*/
asm volatile ("movw %0, %%es" :: "r" (ctxt->es));
asm volatile ("movw %0, %%fs" :: "r" (ctxt->fs));
asm volatile ("movw %0, %%gs" :: "r" (ctxt->gs));
asm volatile ("movw %0, %%ss" :: "r" (ctxt->ss));
/*
* sysenter MSRs
*/
if (boot_cpu_has(X86_FEATURE_SEP))
enable_sep_cpu();
fix_processor_context();
do_fpu_end();
mtrr_ap_init();
}
void restore_processor_state(void)
{
__restore_processor_state(&saved_context);
}
/* Needed by apm.c */
EXPORT_SYMBOL(save_processor_state);
EXPORT_SYMBOL(restore_processor_state);
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