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To:     "Rafael J. Wysocki" <rafael@kernel.org>,
        Len Brown <len.brown@intel.com>, Pavel Machek <pavel@ucw.cz>,
        Thomas Gleixner <tglx@linutronix.de>,
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CC:     <CobeChen@zhaoxin.com>, <TimGuo@zhaoxin.com>,
        <LindaChai@zhaoxin.com>, <LeoLiu@zhaoxin.com>,
        ACPI Devel Maling List <linux-acpi@vger.kernel.org>
From:   Tony W Wang-oc <TonyWWang-oc@zhaoxin.com>
Subject: [PATCH V1] x86/cstate: Add Zhaoxin/Centaur ACPI Cx FFH MWAIT support
Message-ID: <0b583b7e-dcd3-be51-f367-1c12ac841d3f@zhaoxin.com>
Date:   Thu, 23 Jun 2022 09:26:57 +0800
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Recent Zhaoxin/Centaur 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/Centaur
systems. So let function ffh_cstate_init() support These CPUs 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