From b3779261314ec31b9c2ac96d58820cf3ab7f3cdc Mon Sep 17 00:00:00 2001 From: Steven Noonan Date: Wed, 17 Nov 2021 00:26:20 -0800 Subject: [PATCH 12/21] x86: save/restore TSC counter value during sleep/wake Signed-off-by: Steven Noonan Signed-off-by: Cristian Ciocaltea --- arch/x86/kernel/acpi/sleep.c | 5 +++++ arch/x86/realmode/rm/wakeup.h | 3 +++ arch/x86/realmode/rm/wakeup_asm.S | 12 ++++++++++++ 3 files changed, 20 insertions(+) diff --git a/arch/x86/kernel/acpi/sleep.c b/arch/x86/kernel/acpi/sleep.c index 6dfecb27b846..07b7f6e578e8 100644 --- a/arch/x86/kernel/acpi/sleep.c +++ b/arch/x86/kernel/acpi/sleep.c @@ -103,6 +103,11 @@ int x86_acpi_suspend_lowlevel(void) header->pmode_misc_en_high)) header->pmode_behavior |= (1 << WAKEUP_BEHAVIOR_RESTORE_MISC_ENABLE); + if (!rdmsr_safe(MSR_IA32_TSC, + &header->pmode_tsc_low, + &header->pmode_tsc_high)) + header->pmode_behavior |= + (1 << WAKEUP_BEHAVIOR_RESTORE_TSC); header->realmode_flags = acpi_realmode_flags; header->real_magic = 0x12345678; diff --git a/arch/x86/realmode/rm/wakeup.h b/arch/x86/realmode/rm/wakeup.h index 0e4fd08ae447..c728d8563de1 100644 --- a/arch/x86/realmode/rm/wakeup.h +++ b/arch/x86/realmode/rm/wakeup.h @@ -23,6 +23,8 @@ struct wakeup_header { u64 pmode_gdt; u32 pmode_misc_en_low; /* Protected mode MISC_ENABLE */ u32 pmode_misc_en_high; + u32 pmode_tsc_low; + u32 pmode_tsc_high; u32 pmode_behavior; /* Wakeup routine behavior flags */ u32 realmode_flags; u32 real_magic; @@ -39,5 +41,6 @@ extern struct wakeup_header wakeup_header; #define WAKEUP_BEHAVIOR_RESTORE_MISC_ENABLE 0 #define WAKEUP_BEHAVIOR_RESTORE_CR4 1 #define WAKEUP_BEHAVIOR_RESTORE_EFER 2 +#define WAKEUP_BEHAVIOR_RESTORE_TSC 3 #endif /* ARCH_X86_KERNEL_ACPI_RM_WAKEUP_H */ diff --git a/arch/x86/realmode/rm/wakeup_asm.S b/arch/x86/realmode/rm/wakeup_asm.S index 02d0ba16ae33..0154ef895960 100644 --- a/arch/x86/realmode/rm/wakeup_asm.S +++ b/arch/x86/realmode/rm/wakeup_asm.S @@ -27,6 +27,7 @@ SYM_DATA_START(wakeup_header) pmode_efer: .quad 0 /* Saved EFER */ pmode_gdt: .quad 0 pmode_misc_en: .quad 0 /* Saved MISC_ENABLE MSR */ + pmode_tsc: .quad 0 /* Saved TSC MSR */ pmode_behavior: .long 0 /* Wakeup behavior flags */ realmode_flags: .long 0 real_magic: .long 0 @@ -104,6 +105,17 @@ SYM_CODE_START(wakeup_start) wrmsr 1: + /* Restore TSC */ + movl pmode_behavior, %edi + btl $WAKEUP_BEHAVIOR_RESTORE_TSC, %edi + jnc 1f + + movl pmode_tsc, %eax + movl pmode_tsc + 4, %edx + movl $MSR_IA32_TSC, %ecx + wrmsr +1: + /* Do any other stuff... */ #ifndef CONFIG_64BIT -- 2.45.2