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-rw-r--r--arch/x86/kernel/acpi/sleep.c201
1 files changed, 201 insertions, 0 deletions
diff --git a/arch/x86/kernel/acpi/sleep.c b/arch/x86/kernel/acpi/sleep.c
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+++ b/arch/x86/kernel/acpi/sleep.c
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+// SPDX-License-Identifier: GPL-2.0
+/*
+ * sleep.c - x86-specific ACPI sleep support.
+ *
+ * Copyright (C) 2001-2003 Patrick Mochel
+ * Copyright (C) 2001-2003 Pavel Machek <pavel@ucw.cz>
+ */
+
+#include <linux/acpi.h>
+#include <linux/memblock.h>
+#include <linux/dmi.h>
+#include <linux/cpumask.h>
+#include <linux/pgtable.h>
+#include <asm/segment.h>
+#include <asm/desc.h>
+#include <asm/cacheflush.h>
+#include <asm/realmode.h>
+#include <asm/hypervisor.h>
+#include <asm/smp.h>
+
+#include <linux/ftrace.h>
+#include "../../realmode/rm/wakeup.h"
+#include "sleep.h"
+
+unsigned long acpi_realmode_flags;
+
+#if defined(CONFIG_SMP) && defined(CONFIG_64BIT)
+static char temp_stack[4096];
+#endif
+
+/**
+ * acpi_get_wakeup_address - provide physical address for S3 wakeup
+ *
+ * Returns the physical address where the kernel should be resumed after the
+ * system awakes from S3, e.g. for programming into the firmware waking vector.
+ */
+unsigned long acpi_get_wakeup_address(void)
+{
+ return ((unsigned long)(real_mode_header->wakeup_start));
+}
+
+/**
+ * x86_acpi_enter_sleep_state - enter sleep state
+ * @state: Sleep state to enter.
+ *
+ * Wrapper around acpi_enter_sleep_state() to be called by assembly.
+ */
+asmlinkage acpi_status __visible x86_acpi_enter_sleep_state(u8 state)
+{
+ return acpi_enter_sleep_state(state);
+}
+
+/**
+ * x86_acpi_suspend_lowlevel - save kernel state
+ *
+ * Create an identity mapped page table and copy the wakeup routine to
+ * low memory.
+ */
+int x86_acpi_suspend_lowlevel(void)
+{
+ struct wakeup_header *header =
+ (struct wakeup_header *) __va(real_mode_header->wakeup_header);
+
+ if (header->signature != WAKEUP_HEADER_SIGNATURE) {
+ printk(KERN_ERR "wakeup header does not match\n");
+ return -EINVAL;
+ }
+
+ header->video_mode = saved_video_mode;
+
+ header->pmode_behavior = 0;
+
+#ifndef CONFIG_64BIT
+ native_store_gdt((struct desc_ptr *)&header->pmode_gdt);
+
+ /*
+ * We have to check that we can write back the value, and not
+ * just read it. At least on 90 nm Pentium M (Family 6, Model
+ * 13), reading an invalid MSR is not guaranteed to trap, see
+ * Erratum X4 in "Intel Pentium M Processor on 90 nm Process
+ * with 2-MB L2 Cache and IntelĀ® Processor A100 and A110 on 90
+ * nm process with 512-KB L2 Cache Specification Update".
+ */
+ if (!rdmsr_safe(MSR_EFER,
+ &header->pmode_efer_low,
+ &header->pmode_efer_high) &&
+ !wrmsr_safe(MSR_EFER,
+ header->pmode_efer_low,
+ header->pmode_efer_high))
+ header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_EFER);
+#endif /* !CONFIG_64BIT */
+
+ header->pmode_cr0 = read_cr0();
+ if (__this_cpu_read(cpu_info.cpuid_level) >= 0) {
+ header->pmode_cr4 = __read_cr4();
+ header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_CR4);
+ }
+ if (!rdmsr_safe(MSR_IA32_MISC_ENABLE,
+ &header->pmode_misc_en_low,
+ &header->pmode_misc_en_high) &&
+ !wrmsr_safe(MSR_IA32_MISC_ENABLE,
+ header->pmode_misc_en_low,
+ header->pmode_misc_en_high))
+ header->pmode_behavior |=
+ (1 << WAKEUP_BEHAVIOR_RESTORE_MISC_ENABLE);
+ header->realmode_flags = acpi_realmode_flags;
+ header->real_magic = 0x12345678;
+
+#ifndef CONFIG_64BIT
+ header->pmode_entry = (u32)&wakeup_pmode_return;
+ header->pmode_cr3 = (u32)__pa_symbol(initial_page_table);
+ saved_magic = 0x12345678;
+#else /* CONFIG_64BIT */
+#ifdef CONFIG_SMP
+ /*
+ * As each CPU starts up, it will find its own stack pointer
+ * from its current_task->thread.sp. Typically that will be
+ * the idle thread for a newly-started AP, or even the boot
+ * CPU which will find it set to &init_task in the static
+ * per-cpu data.
+ *
+ * Make the resuming CPU use the temporary stack at startup
+ * by setting current->thread.sp to point to that. The true
+ * %rsp will be restored with the rest of the CPU context,
+ * by do_suspend_lowlevel(). And unwinders don't care about
+ * the abuse of ->thread.sp because it's a dead variable
+ * while the thread is running on the CPU anyway; the true
+ * value is in the actual %rsp register.
+ */
+ current->thread.sp = (unsigned long)temp_stack + sizeof(temp_stack);
+ /*
+ * Ensure the CPU knows which one it is when it comes back, if
+ * it isn't in parallel mode and expected to work that out for
+ * itself.
+ */
+ if (!(smpboot_control & STARTUP_PARALLEL_MASK))
+ smpboot_control = smp_processor_id();
+#endif
+ initial_code = (unsigned long)wakeup_long64;
+ saved_magic = 0x123456789abcdef0L;
+#endif /* CONFIG_64BIT */
+
+ /*
+ * Pause/unpause graph tracing around do_suspend_lowlevel as it has
+ * inconsistent call/return info after it jumps to the wakeup vector.
+ */
+ pause_graph_tracing();
+ do_suspend_lowlevel();
+ unpause_graph_tracing();
+ return 0;
+}
+
+static int __init acpi_sleep_setup(char *str)
+{
+ while ((str != NULL) && (*str != '\0')) {
+ if (strncmp(str, "s3_bios", 7) == 0)
+ acpi_realmode_flags |= 1;
+ if (strncmp(str, "s3_mode", 7) == 0)
+ acpi_realmode_flags |= 2;
+ if (strncmp(str, "s3_beep", 7) == 0)
+ acpi_realmode_flags |= 4;
+#ifdef CONFIG_HIBERNATION
+ if (strncmp(str, "s4_hwsig", 8) == 0)
+ acpi_check_s4_hw_signature = 1;
+ if (strncmp(str, "s4_nohwsig", 10) == 0)
+ acpi_check_s4_hw_signature = 0;
+#endif
+ if (strncmp(str, "nonvs", 5) == 0)
+ acpi_nvs_nosave();
+ if (strncmp(str, "nonvs_s3", 8) == 0)
+ acpi_nvs_nosave_s3();
+ if (strncmp(str, "old_ordering", 12) == 0)
+ acpi_old_suspend_ordering();
+ if (strncmp(str, "nobl", 4) == 0)
+ acpi_sleep_no_blacklist();
+ str = strchr(str, ',');
+ if (str != NULL)
+ str += strspn(str, ", \t");
+ }
+ return 1;
+}
+
+__setup("acpi_sleep=", acpi_sleep_setup);
+
+#if defined(CONFIG_HIBERNATION) && defined(CONFIG_HYPERVISOR_GUEST)
+static int __init init_s4_sigcheck(void)
+{
+ /*
+ * If running on a hypervisor, honour the ACPI specification
+ * by default and trigger a clean reboot when the hardware
+ * signature in FACS is changed after hibernation.
+ */
+ if (acpi_check_s4_hw_signature == -1 &&
+ !hypervisor_is_type(X86_HYPER_NATIVE))
+ acpi_check_s4_hw_signature = 1;
+
+ return 0;
+}
+/* This must happen before acpi_init() which is a subsys initcall */
+arch_initcall(init_s4_sigcheck);
+#endif