cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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sleep.c (5214B)


      1// SPDX-License-Identifier: GPL-2.0
      2/*
      3 * sleep.c - x86-specific ACPI sleep support.
      4 *
      5 *  Copyright (C) 2001-2003 Patrick Mochel
      6 *  Copyright (C) 2001-2003 Pavel Machek <pavel@ucw.cz>
      7 */
      8
      9#include <linux/acpi.h>
     10#include <linux/memblock.h>
     11#include <linux/dmi.h>
     12#include <linux/cpumask.h>
     13#include <linux/pgtable.h>
     14#include <asm/segment.h>
     15#include <asm/desc.h>
     16#include <asm/cacheflush.h>
     17#include <asm/realmode.h>
     18#include <asm/hypervisor.h>
     19
     20#include <linux/ftrace.h>
     21#include "../../realmode/rm/wakeup.h"
     22#include "sleep.h"
     23
     24unsigned long acpi_realmode_flags;
     25
     26#if defined(CONFIG_SMP) && defined(CONFIG_64BIT)
     27static char temp_stack[4096];
     28#endif
     29
     30/**
     31 * acpi_get_wakeup_address - provide physical address for S3 wakeup
     32 *
     33 * Returns the physical address where the kernel should be resumed after the
     34 * system awakes from S3, e.g. for programming into the firmware waking vector.
     35 */
     36unsigned long acpi_get_wakeup_address(void)
     37{
     38	return ((unsigned long)(real_mode_header->wakeup_start));
     39}
     40
     41/**
     42 * x86_acpi_enter_sleep_state - enter sleep state
     43 * @state: Sleep state to enter.
     44 *
     45 * Wrapper around acpi_enter_sleep_state() to be called by assembly.
     46 */
     47asmlinkage acpi_status __visible x86_acpi_enter_sleep_state(u8 state)
     48{
     49	return acpi_enter_sleep_state(state);
     50}
     51
     52/**
     53 * x86_acpi_suspend_lowlevel - save kernel state
     54 *
     55 * Create an identity mapped page table and copy the wakeup routine to
     56 * low memory.
     57 */
     58int x86_acpi_suspend_lowlevel(void)
     59{
     60	struct wakeup_header *header =
     61		(struct wakeup_header *) __va(real_mode_header->wakeup_header);
     62
     63	if (header->signature != WAKEUP_HEADER_SIGNATURE) {
     64		printk(KERN_ERR "wakeup header does not match\n");
     65		return -EINVAL;
     66	}
     67
     68	header->video_mode = saved_video_mode;
     69
     70	header->pmode_behavior = 0;
     71
     72#ifndef CONFIG_64BIT
     73	native_store_gdt((struct desc_ptr *)&header->pmode_gdt);
     74
     75	/*
     76	 * We have to check that we can write back the value, and not
     77	 * just read it.  At least on 90 nm Pentium M (Family 6, Model
     78	 * 13), reading an invalid MSR is not guaranteed to trap, see
     79	 * Erratum X4 in "Intel Pentium M Processor on 90 nm Process
     80	 * with 2-MB L2 Cache and IntelĀ® Processor A100 and A110 on 90
     81	 * nm process with 512-KB L2 Cache Specification Update".
     82	 */
     83	if (!rdmsr_safe(MSR_EFER,
     84			&header->pmode_efer_low,
     85			&header->pmode_efer_high) &&
     86	    !wrmsr_safe(MSR_EFER,
     87			header->pmode_efer_low,
     88			header->pmode_efer_high))
     89		header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_EFER);
     90#endif /* !CONFIG_64BIT */
     91
     92	header->pmode_cr0 = read_cr0();
     93	if (__this_cpu_read(cpu_info.cpuid_level) >= 0) {
     94		header->pmode_cr4 = __read_cr4();
     95		header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_CR4);
     96	}
     97	if (!rdmsr_safe(MSR_IA32_MISC_ENABLE,
     98			&header->pmode_misc_en_low,
     99			&header->pmode_misc_en_high) &&
    100	    !wrmsr_safe(MSR_IA32_MISC_ENABLE,
    101			header->pmode_misc_en_low,
    102			header->pmode_misc_en_high))
    103		header->pmode_behavior |=
    104			(1 << WAKEUP_BEHAVIOR_RESTORE_MISC_ENABLE);
    105	header->realmode_flags = acpi_realmode_flags;
    106	header->real_magic = 0x12345678;
    107
    108#ifndef CONFIG_64BIT
    109	header->pmode_entry = (u32)&wakeup_pmode_return;
    110	header->pmode_cr3 = (u32)__pa_symbol(initial_page_table);
    111	saved_magic = 0x12345678;
    112#else /* CONFIG_64BIT */
    113#ifdef CONFIG_SMP
    114	initial_stack = (unsigned long)temp_stack + sizeof(temp_stack);
    115	early_gdt_descr.address =
    116			(unsigned long)get_cpu_gdt_rw(smp_processor_id());
    117	initial_gs = per_cpu_offset(smp_processor_id());
    118#endif
    119	initial_code = (unsigned long)wakeup_long64;
    120       saved_magic = 0x123456789abcdef0L;
    121#endif /* CONFIG_64BIT */
    122
    123	/*
    124	 * Pause/unpause graph tracing around do_suspend_lowlevel as it has
    125	 * inconsistent call/return info after it jumps to the wakeup vector.
    126	 */
    127	pause_graph_tracing();
    128	do_suspend_lowlevel();
    129	unpause_graph_tracing();
    130	return 0;
    131}
    132
    133static int __init acpi_sleep_setup(char *str)
    134{
    135	while ((str != NULL) && (*str != '\0')) {
    136		if (strncmp(str, "s3_bios", 7) == 0)
    137			acpi_realmode_flags |= 1;
    138		if (strncmp(str, "s3_mode", 7) == 0)
    139			acpi_realmode_flags |= 2;
    140		if (strncmp(str, "s3_beep", 7) == 0)
    141			acpi_realmode_flags |= 4;
    142#ifdef CONFIG_HIBERNATION
    143		if (strncmp(str, "s4_hwsig", 8) == 0)
    144			acpi_check_s4_hw_signature = 1;
    145		if (strncmp(str, "s4_nohwsig", 10) == 0)
    146			acpi_check_s4_hw_signature = 0;
    147#endif
    148		if (strncmp(str, "nonvs", 5) == 0)
    149			acpi_nvs_nosave();
    150		if (strncmp(str, "nonvs_s3", 8) == 0)
    151			acpi_nvs_nosave_s3();
    152		if (strncmp(str, "old_ordering", 12) == 0)
    153			acpi_old_suspend_ordering();
    154		if (strncmp(str, "nobl", 4) == 0)
    155			acpi_sleep_no_blacklist();
    156		str = strchr(str, ',');
    157		if (str != NULL)
    158			str += strspn(str, ", \t");
    159	}
    160	return 1;
    161}
    162
    163__setup("acpi_sleep=", acpi_sleep_setup);
    164
    165#if defined(CONFIG_HIBERNATION) && defined(CONFIG_HYPERVISOR_GUEST)
    166static int __init init_s4_sigcheck(void)
    167{
    168	/*
    169	 * If running on a hypervisor, honour the ACPI specification
    170	 * by default and trigger a clean reboot when the hardware
    171	 * signature in FACS is changed after hibernation.
    172	 */
    173	if (acpi_check_s4_hw_signature == -1 &&
    174	    !hypervisor_is_type(X86_HYPER_NATIVE))
    175		acpi_check_s4_hw_signature = 1;
    176
    177	return 0;
    178}
    179/* This must happen before acpi_init() which is a subsys initcall */
    180arch_initcall(init_s4_sigcheck);
    181#endif