diff options
Diffstat (limited to 'arch/x86/power/cpu.c')
| -rw-r--r-- | arch/x86/power/cpu.c | 241 |
1 files changed, 241 insertions, 0 deletions
diff --git a/arch/x86/power/cpu.c b/arch/x86/power/cpu.c new file mode 100644 index 00000000000..394cbb88987 --- /dev/null +++ b/arch/x86/power/cpu.c @@ -0,0 +1,241 @@ +/* + * Suspend support specific for i386/x86-64. + * + * Distribute under GPLv2 + * + * Copyright (c) 2007 Rafael J. Wysocki <rjw@sisk.pl> + * Copyright (c) 2002 Pavel Machek <pavel@suse.cz> + * Copyright (c) 2001 Patrick Mochel <mochel@osdl.org> + */ + +#include <linux/suspend.h> +#include <linux/smp.h> + +#include <asm/pgtable.h> +#include <asm/proto.h> +#include <asm/mtrr.h> +#include <asm/page.h> +#include <asm/mce.h> +#include <asm/xcr.h> +#include <asm/suspend.h> +#include <asm/debugreg.h> + +#ifdef CONFIG_X86_32 +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; +#else +/* CONFIG_X86_64 */ +struct saved_context saved_context; +#endif + +/** + * __save_processor_state - save CPU registers before creating a + * hibernation image and before restoring the memory state from it + * @ctxt - structure to store the registers contents in + * + * NOTE: If there is a CPU register the modification of which by the + * boot kernel (ie. the kernel used for loading the hibernation image) + * might affect the operations of the restored target kernel (ie. the one + * saved in the hibernation image), then its contents must be saved by this + * function. In other words, if kernel A is hibernated and different + * kernel B is used for loading the hibernation image into memory, the + * kernel A's __save_processor_state() function must save all registers + * needed by kernel A, so that it can operate correctly after the resume + * regardless of what kernel B does in the meantime. + */ +static void __save_processor_state(struct saved_context *ctxt) +{ +#ifdef CONFIG_X86_32 + mtrr_save_fixed_ranges(NULL); +#endif + kernel_fpu_begin(); + + /* + * descriptor tables + */ +#ifdef CONFIG_X86_32 + store_gdt(&ctxt->gdt); + store_idt(&ctxt->idt); +#else +/* CONFIG_X86_64 */ + store_gdt((struct desc_ptr *)&ctxt->gdt_limit); + store_idt((struct desc_ptr *)&ctxt->idt_limit); +#endif + store_tr(ctxt->tr); + + /* XMM0..XMM15 should be handled by kernel_fpu_begin(). */ + /* + * segment registers + */ +#ifdef CONFIG_X86_32 + savesegment(es, ctxt->es); + savesegment(fs, ctxt->fs); + savesegment(gs, ctxt->gs); + savesegment(ss, ctxt->ss); +#else +/* CONFIG_X86_64 */ + asm volatile ("movw %%ds, %0" : "=m" (ctxt->ds)); + 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)); + + rdmsrl(MSR_FS_BASE, ctxt->fs_base); + rdmsrl(MSR_GS_BASE, ctxt->gs_base); + rdmsrl(MSR_KERNEL_GS_BASE, ctxt->gs_kernel_base); + mtrr_save_fixed_ranges(NULL); + + rdmsrl(MSR_EFER, ctxt->efer); +#endif + + /* + * control registers + */ + ctxt->cr0 = read_cr0(); + ctxt->cr2 = read_cr2(); + ctxt->cr3 = read_cr3(); +#ifdef CONFIG_X86_32 + ctxt->cr4 = read_cr4_safe(); +#else +/* CONFIG_X86_64 */ + ctxt->cr4 = read_cr4(); + ctxt->cr8 = read_cr8(); +#endif + hw_breakpoint_disable(); +} + +/* Needed by apm.c */ +void save_processor_state(void) +{ + __save_processor_state(&saved_context); +} +#ifdef CONFIG_X86_32 +EXPORT_SYMBOL(save_processor_state); +#endif + +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. + */ + +#ifdef CONFIG_X86_64 + get_cpu_gdt_table(cpu)[GDT_ENTRY_TSS].type = 9; + + syscall_init(); /* This sets MSR_*STAR and related */ +#endif + load_TR_desc(); /* This does ltr */ + load_LDT(¤t->active_mm->context); /* This does lldt */ + + /* + * Now maybe reload the debug registers + */ + load_debug_registers(); +} + +/** + * __restore_processor_state - restore the contents of CPU registers saved + * by __save_processor_state() + * @ctxt - structure to load the registers contents from + */ +static void __restore_processor_state(struct saved_context *ctxt) +{ + /* + * control registers + */ + /* cr4 was introduced in the Pentium CPU */ +#ifdef CONFIG_X86_32 + if (ctxt->cr4) + write_cr4(ctxt->cr4); +#else +/* CONFIG X86_64 */ + wrmsrl(MSR_EFER, ctxt->efer); + write_cr8(ctxt->cr8); + write_cr4(ctxt->cr4); +#endif + 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(). + */ +#ifdef CONFIG_X86_32 + load_gdt(&ctxt->gdt); + load_idt(&ctxt->idt); +#else +/* CONFIG_X86_64 */ + load_gdt((const struct desc_ptr *)&ctxt->gdt_limit); + load_idt((const struct desc_ptr *)&ctxt->idt_limit); +#endif + + /* + * segment registers + */ +#ifdef CONFIG_X86_32 + 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(); +#else +/* CONFIG_X86_64 */ + asm volatile ("movw %0, %%ds" :: "r" (ctxt->ds)); + asm volatile ("movw %0, %%es" :: "r" (ctxt->es)); + asm volatile ("movw %0, %%fs" :: "r" (ctxt->fs)); + load_gs_index(ctxt->gs); + asm volatile ("movw %0, %%ss" :: "r" (ctxt->ss)); + + wrmsrl(MSR_FS_BASE, ctxt->fs_base); + wrmsrl(MSR_GS_BASE, ctxt->gs_base); + wrmsrl(MSR_KERNEL_GS_BASE, ctxt->gs_kernel_base); +#endif + + /* + * restore XCR0 for xsave capable cpu's. + */ + if (cpu_has_xsave) + xsetbv(XCR_XFEATURE_ENABLED_MASK, pcntxt_mask); + + fix_processor_context(); + + do_fpu_end(); + mtrr_ap_init(); + +#ifdef CONFIG_X86_32 + mcheck_init(&boot_cpu_data); +#endif +} + +/* Needed by apm.c */ +void restore_processor_state(void) +{ + __restore_processor_state(&saved_context); +} +#ifdef CONFIG_X86_32 +EXPORT_SYMBOL(restore_processor_state); +#endif |