/* * 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/smp.h> #include <linux/suspend.h> #include <asm/proto.h> #include <asm/page.h> #include <asm/pgtable.h> struct saved_context saved_context; unsigned long saved_context_eax, saved_context_ebx, saved_context_ecx, saved_context_edx; unsigned long saved_context_esp, saved_context_ebp, saved_context_esi, saved_context_edi; unsigned long saved_context_r08, saved_context_r09, saved_context_r10, saved_context_r11; unsigned long saved_context_r12, saved_context_r13, saved_context_r14, saved_context_r15; 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)); /* XMM0..XMM15 should be handled by kernel_fpu_begin(). */ /* EFER should be constant for kernel version, no need to handle it. */ /* * segment registers */ 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); /* * control registers */ asm volatile ("movq %%cr0, %0" : "=r" (ctxt->cr0)); asm volatile ("movq %%cr2, %0" : "=r" (ctxt->cr2)); asm volatile ("movq %%cr3, %0" : "=r" (ctxt->cr3)); asm volatile ("movq %%cr4, %0" : "=r" (ctxt->cr4)); asm volatile ("movq %%cr8, %0" : "=r" (ctxt->cr8)); } void save_processor_state(void) { __save_processor_state(&saved_context); } static void do_fpu_end(void) { /* * Restore FPU regs if necessary */ kernel_fpu_end(); } void __restore_processor_state(struct saved_context *ctxt) { /* * control registers */ asm volatile ("movq %0, %%cr8" :: "r" (ctxt->cr8)); asm volatile ("movq %0, %%cr4" :: "r" (ctxt->cr4)); asm volatile ("movq %0, %%cr3" :: "r" (ctxt->cr3)); asm volatile ("movq %0, %%cr2" :: "r" (ctxt->cr2)); asm volatile ("movq %0, %%cr0" :: "r" (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, %%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); fix_processor_context(); do_fpu_end(); mtrr_ap_init(); } void restore_processor_state(void) { __restore_processor_state(&saved_context); } 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 neccessary. But... This is neccessary, because 386 hardware has concept of busy TSS or some similar stupidity. */ cpu_gdt(cpu)[GDT_ENTRY_TSS].type = 9; syscall_init(); /* This sets MSR_*STAR and related */ load_TR_desc(); /* This does ltr */ load_LDT(¤t->active_mm->context); /* This does lldt */ /* * Now maybe reload the debug registers */ if (current->thread.debugreg7){ loaddebug(¤t->thread, 0); loaddebug(¤t->thread, 1); loaddebug(¤t->thread, 2); loaddebug(¤t->thread, 3); /* no 4 and 5 */ loaddebug(¤t->thread, 6); loaddebug(¤t->thread, 7); } } #ifdef CONFIG_SOFTWARE_SUSPEND /* Defined in arch/x86_64/kernel/suspend_asm.S */ extern int restore_image(void); pgd_t *temp_level4_pgt; static int res_phys_pud_init(pud_t *pud, unsigned long address, unsigned long end) { long i, j; i = pud_index(address); pud = pud + i; for (; i < PTRS_PER_PUD; pud++, i++) { unsigned long paddr; pmd_t *pmd; paddr = address + i*PUD_SIZE; if (paddr >= end) break; pmd = (pmd_t *)get_safe_page(GFP_ATOMIC); if (!pmd) return -ENOMEM; set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE)); for (j = 0; j < PTRS_PER_PMD; pmd++, j++, paddr += PMD_SIZE) { unsigned long pe; if (paddr >= end) break; pe = _PAGE_NX | _PAGE_PSE | _KERNPG_TABLE | paddr; pe &= __supported_pte_mask; set_pmd(pmd, __pmd(pe)); } } return 0; } static int set_up_temporary_mappings(void) { unsigned long start, end, next; int error; temp_level4_pgt = (pgd_t *)get_safe_page(GFP_ATOMIC); if (!temp_level4_pgt) return -ENOMEM; /* It is safe to reuse the original kernel mapping */ set_pgd(temp_level4_pgt + pgd_index(__START_KERNEL_map), init_level4_pgt[pgd_index(__START_KERNEL_map)]); /* Set up the direct mapping from scratch */ start = (unsigned long)pfn_to_kaddr(0); end = (unsigned long)pfn_to_kaddr(end_pfn); for (; start < end; start = next) { pud_t *pud = (pud_t *)get_safe_page(GFP_ATOMIC); if (!pud) return -ENOMEM; next = start + PGDIR_SIZE; if (next > end) next = end; if ((error = res_phys_pud_init(pud, __pa(start), __pa(next)))) return error; set_pgd(temp_level4_pgt + pgd_index(start), mk_kernel_pgd(__pa(pud))); } return 0; } int swsusp_arch_resume(void) { int error; /* We have got enough memory and from now on we cannot recover */ if ((error = set_up_temporary_mappings())) return error; restore_image(); return 0; } #endif /* CONFIG_SOFTWARE_SUSPEND */