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-rw-r--r--arch/x86/power/cpu.c241
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 000000000000..394cbb88987c
--- /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(&current->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