diff options
Diffstat (limited to 'arch/x86/kernel/acpi/cstate.c')
| -rw-r--r-- | arch/x86/kernel/acpi/cstate.c | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/arch/x86/kernel/acpi/cstate.c b/arch/x86/kernel/acpi/cstate.c index 158ad1483c43..cb6e076a6d39 100644 --- a/arch/x86/kernel/acpi/cstate.c +++ b/arch/x86/kernel/acpi/cstate.c @@ -51,6 +51,18 @@ void acpi_processor_power_init_bm_check(struct acpi_processor_flags *flags, if (c->x86_vendor == X86_VENDOR_INTEL && (c->x86 > 0xf || (c->x86 == 6 && c->x86_model >= 0x0f))) flags->bm_control = 0; + /* + * For all recent Centaur CPUs, the ucode will make sure that each + * core can keep cache coherence with each other while entering C3 + * type state. So, set bm_check to 1 to indicate that the kernel + * doesn't need to execute a cache flush operation (WBINVD) when + * entering C3 type state. + */ + if (c->x86_vendor == X86_VENDOR_CENTAUR) { + if (c->x86 > 6 || (c->x86 == 6 && c->x86_model == 0x0f && + c->x86_stepping >= 0x0e)) + flags->bm_check = 1; + } } EXPORT_SYMBOL(acpi_processor_power_init_bm_check); |