/* * 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; static 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(); } /* Needed by apm.c */ void save_processor_state(void) { __save_processor_state(&saved_context); } EXPORT_SYMBOL(save_processor_state); 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.debugreg7) { set_debugreg(current->thread.debugreg0, 0); set_debugreg(current->thread.debugreg1, 1); set_debugreg(current->thread.debugreg2, 2); set_debugreg(current->thread.debugreg3, 3); /* no 4 and 5 */ set_debugreg(current->thread.debugreg6, 6); set_debugreg(current->thread.debugreg7, 7); } } static 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); } /* Needed by apm.c */ void restore_processor_state(void) { __restore_processor_state(&saved_context); } EXPORT_SYMBOL(restore_processor_state);