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To:     <rafael@kernel.org>, <len.brown@intel.com>, <pavel@ucw.cz>,
        <tglx@linutronix.de>, <mingo@redhat.com>, <bp@alien8.de>,
        <dave.hansen@linux.intel.com>, <x86@kernel.org>, <hpa@zytor.com>,
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CC:     <CobeChen@zhaoxin.com>, <TimGuo@zhaoxin.com>,
        <LindaChai@zhaoxin.com>, <LeoLiu@zhaoxin.com>
From:   Tony W Wang-oc <TonyWWang-oc@zhaoxin.com>
Subject: [PATCH] x86/cstate: Add Zhaoxin ACPI Cx FFH MWAIT support
Message-ID: <bccae278-e735-4681-cb3a-41359e42032b@zhaoxin.com>
Date:   Wed, 22 Jun 2022 11:29:41 +0800
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Recent Zhaoxin CPUs support X86_FEATURE_MWAIT that implies the
MONITOR/MWAIT instructions can be used for ACPI Cx state. The BIOS
declares Cx state in _CST object to use FFH on Zhaoxin systems. So
let function ffh_cstate_init() support Zhaoxin too.

Signed-off-by: Tony W Wang-oc <TonyWWang-oc@zhaoxin.com>
---
  arch/x86/kernel/acpi/cstate.c | 4 +++-
  1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kernel/acpi/cstate.c b/arch/x86/kernel/acpi/cstate.c
index 7945eae..d4185e1 100644
--- a/arch/x86/kernel/acpi/cstate.c
+++ b/arch/x86/kernel/acpi/cstate.c
@@ -213,7 +213,9 @@ static int __init ffh_cstate_init(void)

  	if (c->x86_vendor != X86_VENDOR_INTEL &&
  	    c->x86_vendor != X86_VENDOR_AMD &&
-	    c->x86_vendor != X86_VENDOR_HYGON)
+	    c->x86_vendor != X86_VENDOR_HYGON &&
+	    c->x86_vendor != X86_VENDOR_CENTAUR &&
+	    c->x86_vendor != X86_VENDOR_ZHAOXIN)
  		return -1;

  	cpu_cstate_entry = alloc_percpu(struct cstate_entry);
-- 
2.7.4