[PATCH kernel-4.19 2/2] x86/acpi/cstate: Add Zhaoxin processors support for cache flush policy in C3
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Signed-off-by: LeoLiu-oc <LeoLiu-oc@zhaoxin.com> --- arch/x86/kernel/acpi/cstate.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/arch/x86/kernel/acpi/cstate.c b/arch/x86/kernel/acpi/cstate.c index 45745ecaa624..5eebe05b00fb 100644 --- a/arch/x86/kernel/acpi/cstate.c +++ b/arch/x86/kernel/acpi/cstate.c @@ -63,6 +63,21 @@ void acpi_processor_power_init_bm_check(struct acpi_processor_flags *flags, c->x86_stepping >= 0x0e)) flags->bm_check = 1; } + + if (c->x86_vendor == X86_VENDOR_ZHAOXIN) { + /* + * All Zhaoxin CPUs that support C3 share cache. + * And caches should not be flushed by software while + * entering C3 type state. + */ + flags->bm_check = 1; + /* + * On all recent Zhaoxin platforms, ARB_DISABLE is a nop. + * So, set bm_control to zero to indicate that ARB_DISABLE + * is not required while entering C3 type state. + */ + flags->bm_control = 0; + } } EXPORT_SYMBOL(acpi_processor_power_init_bm_check); -- 2.20.1
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