1 /* 2 * sleep.c - x86-specific ACPI sleep support. 3 * 4 * Copyright (C) 2001-2003 Patrick Mochel 5 * Copyright (C) 2001-2003 Pavel Machek <pavel@ucw.cz> 6 */ 7 8 #include <linux/acpi.h> 9 #include <linux/bootmem.h> 10 #include <linux/memblock.h> 11 #include <linux/dmi.h> 12 #include <linux/cpumask.h> 13 #include <asm/segment.h> 14 #include <asm/desc.h> 15 #include <asm/pgtable.h> 16 #include <asm/cacheflush.h> 17 #include <asm/realmode.h> 18 19 #include "../../realmode/rm/wakeup.h" 20 #include "sleep.h" 21 22 unsigned long acpi_realmode_flags; 23 24 #if defined(CONFIG_SMP) && defined(CONFIG_64BIT) 25 static char temp_stack[4096]; 26 #endif 27 28 /** 29 * x86_acpi_suspend_lowlevel - save kernel state 30 * 31 * Create an identity mapped page table and copy the wakeup routine to 32 * low memory. 33 */ 34 int x86_acpi_suspend_lowlevel(void) 35 { 36 struct wakeup_header *header = 37 (struct wakeup_header *) __va(real_mode_header->wakeup_header); 38 39 if (header->signature != WAKEUP_HEADER_SIGNATURE) { 40 printk(KERN_ERR "wakeup header does not match\n"); 41 return -EINVAL; 42 } 43 44 header->video_mode = saved_video_mode; 45 46 header->pmode_behavior = 0; 47 48 #ifndef CONFIG_64BIT 49 native_store_gdt((struct desc_ptr *)&header->pmode_gdt); 50 51 /* 52 * We have to check that we can write back the value, and not 53 * just read it. At least on 90 nm Pentium M (Family 6, Model 54 * 13), reading an invalid MSR is not guaranteed to trap, see 55 * Erratum X4 in "Intel Pentium M Processor on 90 nm Process 56 * with 2-MB L2 Cache and Intel® Processor A100 and A110 on 90 57 * nm process with 512-KB L2 Cache Specification Update". 58 */ 59 if (!rdmsr_safe(MSR_EFER, 60 &header->pmode_efer_low, 61 &header->pmode_efer_high) && 62 !wrmsr_safe(MSR_EFER, 63 header->pmode_efer_low, 64 header->pmode_efer_high)) 65 header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_EFER); 66 #endif /* !CONFIG_64BIT */ 67 68 header->pmode_cr0 = read_cr0(); 69 if (__this_cpu_read(cpu_info.cpuid_level) >= 0) { 70 header->pmode_cr4 = read_cr4(); 71 header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_CR4); 72 } 73 if (!rdmsr_safe(MSR_IA32_MISC_ENABLE, 74 &header->pmode_misc_en_low, 75 &header->pmode_misc_en_high) && 76 !wrmsr_safe(MSR_IA32_MISC_ENABLE, 77 header->pmode_misc_en_low, 78 header->pmode_misc_en_high)) 79 header->pmode_behavior |= 80 (1 << WAKEUP_BEHAVIOR_RESTORE_MISC_ENABLE); 81 header->realmode_flags = acpi_realmode_flags; 82 header->real_magic = 0x12345678; 83 84 #ifndef CONFIG_64BIT 85 header->pmode_entry = (u32)&wakeup_pmode_return; 86 header->pmode_cr3 = (u32)__pa_symbol(initial_page_table); 87 saved_magic = 0x12345678; 88 #else /* CONFIG_64BIT */ 89 #ifdef CONFIG_SMP 90 stack_start = (unsigned long)temp_stack + sizeof(temp_stack); 91 early_gdt_descr.address = 92 (unsigned long)get_cpu_gdt_table(smp_processor_id()); 93 initial_gs = per_cpu_offset(smp_processor_id()); 94 #endif 95 initial_code = (unsigned long)wakeup_long64; 96 saved_magic = 0x123456789abcdef0L; 97 #endif /* CONFIG_64BIT */ 98 99 do_suspend_lowlevel(); 100 return 0; 101 } 102 103 static int __init acpi_sleep_setup(char *str) 104 { 105 while ((str != NULL) && (*str != '\0')) { 106 if (strncmp(str, "s3_bios", 7) == 0) 107 acpi_realmode_flags |= 1; 108 if (strncmp(str, "s3_mode", 7) == 0) 109 acpi_realmode_flags |= 2; 110 if (strncmp(str, "s3_beep", 7) == 0) 111 acpi_realmode_flags |= 4; 112 #ifdef CONFIG_HIBERNATION 113 if (strncmp(str, "s4_nohwsig", 10) == 0) 114 acpi_no_s4_hw_signature(); 115 #endif 116 if (strncmp(str, "nonvs", 5) == 0) 117 acpi_nvs_nosave(); 118 if (strncmp(str, "nonvs_s3", 8) == 0) 119 acpi_nvs_nosave_s3(); 120 if (strncmp(str, "old_ordering", 12) == 0) 121 acpi_old_suspend_ordering(); 122 str = strchr(str, ','); 123 if (str != NULL) 124 str += strspn(str, ", \t"); 125 } 126 return 1; 127 } 128 129 __setup("acpi_sleep=", acpi_sleep_setup); 130