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-rw-r--r--arch/i386/power/cpu.c152
1 files changed, 152 insertions, 0 deletions
diff --git a/arch/i386/power/cpu.c b/arch/i386/power/cpu.c
new file mode 100644
index 000000000000..cf337c673d92
--- /dev/null
+++ b/arch/i386/power/cpu.c
@@ -0,0 +1,152 @@
+/*
+ * 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>
+
+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;
+
+extern void enable_sep_cpu(void *);
+
+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 ("sldt %0" : "=m" (ctxt->ldt));
+ 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
+ */
+ asm volatile ("movl %%cr0, %0" : "=r" (ctxt->cr0));
+ asm volatile ("movl %%cr2, %0" : "=r" (ctxt->cr2));
+ asm volatile ("movl %%cr3, %0" : "=r" (ctxt->cr3));
+ asm volatile ("movl %%cr4, %0" : "=r" (ctxt->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(&current->active_mm->context); /* This does lldt */
+
+ /*
+ * Now maybe reload the debug registers
+ */
+ if (current->thread.debugreg[7]){
+ loaddebug(&current->thread, 0);
+ loaddebug(&current->thread, 1);
+ loaddebug(&current->thread, 2);
+ loaddebug(&current->thread, 3);
+ /* no 4 and 5 */
+ loaddebug(&current->thread, 6);
+ loaddebug(&current->thread, 7);
+ }
+
+}
+
+void __restore_processor_state(struct saved_context *ctxt)
+{
+
+ /*
+ * control registers
+ */
+ asm volatile ("movl %0, %%cr4" :: "r" (ctxt->cr4));
+ asm volatile ("movl %0, %%cr3" :: "r" (ctxt->cr3));
+ asm volatile ("movl %0, %%cr2" :: "r" (ctxt->cr2));
+ asm volatile ("movl %0, %%cr0" :: "r" (ctxt->cr0));
+
+ /*
+ * 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));
+
+ /*
+ * 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));
+ asm volatile ("lldt %0" :: "m" (ctxt->ldt));
+
+ /*
+ * sysenter MSRs
+ */
+ if (boot_cpu_has(X86_FEATURE_SEP))
+ enable_sep_cpu(NULL);
+
+ fix_processor_context();
+ do_fpu_end();
+}
+
+void restore_processor_state(void)
+{
+ __restore_processor_state(&saved_context);
+}
+
+/* Needed by apm.c */
+EXPORT_SYMBOL(save_processor_state);
+EXPORT_SYMBOL(restore_processor_state);