[ck] [patch v1 2/2] x86/acpi/cstate: Add Zhaoxin processors support for cache flush policy in C3

commit f8c0e061cb83bd528ff0843e717bcebc846d4838 upstream. Same as Intel, Zhaoxin MP CPUs support C3 share cache and on all recent Zhaoxin platforms ARB_DISABLE is a nop. So set related flags correctly in the same way as Intel does. Signed-off-by: Tony W Wang-oc <TonyWWang-oc(a)zhaoxin.com> Signed-off-by: Thomas Gleixner <tglx(a)linutronix.de> Cc: "hpa(a)zytor.com" <hpa(a)zytor.com> Cc: "gregkh(a)linuxfoundation.org" <gregkh(a)linuxfoundation.org> Cc: "rjw(a)rjwysocki.net" <rjw(a)rjwysocki.net> Cc: "lenb(a)kernel.org" <lenb(a)kernel.org> Cc: David Wang <DavidWang(a)zhaoxin.com> Cc: "Cooper Yan(BJ-RD)" <CooperYan(a)zhaoxin.com> Cc: "Qiyuan Wang(BJ-RD)" <QiyuanWang(a)zhaoxin.com> Cc: "Herry Yang(BJ-RD)" <HerryYang(a)zhaoxin.com> Link: https://lkml.kernel.org/r/a370503660994669991a7f7cda7c5e98@zhaoxin.com Signed-off-by: LeoLiu-oc <LeoLiu-oc(a)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 cb6e076a6d39..c010f5bbbc51 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