diff options
Diffstat (limited to 'arch/x86/power/cpu.c')
| -rw-r--r-- | arch/x86/power/cpu.c | 133 |
1 files changed, 133 insertions, 0 deletions
diff --git a/arch/x86/power/cpu.c b/arch/x86/power/cpu.c new file mode 100644 index 0000000..998fd3e --- /dev/null +++ b/arch/x86/power/cpu.c @@ -0,0 +1,133 @@ +/* + * 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/module.h> +#include <linux/suspend.h> +#include <asm/mtrr.h> +#include <asm/mce.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) +{ + mtrr_save_fixed_ranges(NULL); + kernel_fpu_begin(); + + /* + * descriptor tables + */ + store_gdt(&ctxt->gdt); + store_idt(&ctxt->idt); + store_tr(ctxt->tr); + + /* + * segment registers + */ + savesegment(es, ctxt->es); + savesegment(fs, ctxt->fs); + savesegment(gs, ctxt->gs); + savesegment(ss, 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. + */ + kernel_fpu_end(); +} + +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. */ + + 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_cr0(ctxt->cr0); + + /* + * now restore the descriptor tables to their proper values + * ltr is done i fix_processor_context(). + */ + load_gdt(&ctxt->gdt); + load_idt(&ctxt->idt); + + /* + * segment registers + */ + loadsegment(es, ctxt->es); + loadsegment(fs, ctxt->fs); + loadsegment(gs, ctxt->gs); + loadsegment(ss, ctxt->ss); + + /* + * sysenter MSRs + */ + if (boot_cpu_has(X86_FEATURE_SEP)) + enable_sep_cpu(); + + fix_processor_context(); + do_fpu_end(); + mtrr_ap_init(); + mcheck_init(&boot_cpu_data); +} + +void restore_processor_state(void) +{ + __restore_processor_state(&saved_context); +} + +/* Needed by apm.c */ +EXPORT_SYMBOL(save_processor_state); +EXPORT_SYMBOL(restore_processor_state); |