linux-kernel - [PATCH 2/2] x86/mce/amd: carve out MC4

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Message-ID: <1547651417-23583-3-git-send-email-shirish.s@amd.com>
Date:   Wed, 16 Jan 2019 15:10:40 +0000
From:   "S, Shirish" <Shirish.S@....com>
To:     Borislav Petkov <bp@...en8.de>
CC:     Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>,
        "H . Peter Anvin" <hpa@...or.com>,
        "maintainer : X86 ARCHITECTURE" <x86@...nel.org>,
        Tony Luck <tony.luck@...el.com>,
        Vishal Verma <vishal.l.verma@...el.com>,
        "open list : X86 ARCHITECTURE" <linux-kernel@...r.kernel.org>,
        "S, Shirish" <Shirish.S@....com>
Subject: [PATCH 2/2] x86/mce/amd: carve out MC4_MISC thresholding quirk

MC4_MISC thresholding quirk needs to be applied during S5 -> S0 and
S3 -> S0 state transitions, which follow different code paths, hence
carve it out and move it mce_amd_feature_init(), which is  the converging
point of both code paths.

Changelog[v2]:
 - move the quirk to mce/amd.c

Signed-off-by: Shirish S <shirish.s@....com>
---
 arch/x86/kernel/cpu/mce/amd.c  | 34 ++++++++++++++++++++++++++++++++++
 arch/x86/kernel/cpu/mce/core.c | 29 -----------------------------
 2 files changed, 34 insertions(+), 29 deletions(-)

diff --git a/arch/x86/kernel/cpu/mce/amd.c b/arch/x86/kernel/cpu/mce/amd.c
index 89298c8..f6a5c96 100644
--- a/arch/x86/kernel/cpu/mce/amd.c
+++ b/arch/x86/kernel/cpu/mce/amd.c
@@ -545,6 +545,33 @@ prepare_threshold_block(unsigned int bank, unsigned int block, u32 addr,
 	return offset;
 }
 
+void mc4_misc_thresholding_quirk(void)
+{
+	int i;
+	u64 hwcr;
+	bool need_toggle;
+	u32 msrs[] = {
+		0x00000413, /* MC4_MISC0 */
+		0xc0000408, /* MC4_MISC1 */
+	};
+
+	rdmsrl(MSR_K7_HWCR, hwcr);
+
+	/* McStatusWrEn has to be set */
+	need_toggle = !(hwcr & BIT(18));
+
+	if (need_toggle)
+		wrmsrl(MSR_K7_HWCR, hwcr | BIT(18));
+
+	/* Clear CntP bit safely */
+	for (i = 0; i < ARRAY_SIZE(msrs); i++)
+		msr_clear_bit(msrs[i], 62);
+
+	/* restore old settings */
+	if (need_toggle)
+		wrmsrl(MSR_K7_HWCR, hwcr);
+}
+
 /* cpu init entry point, called from mce.c with preempt off */
 void mce_amd_feature_init(struct cpuinfo_x86 *c)
 {
@@ -552,6 +579,13 @@ void mce_amd_feature_init(struct cpuinfo_x86 *c)
 	unsigned int bank, block, cpu = smp_processor_id();
 	int offset = -1;
 
+	/*
+	 * Turn off MC4_MISC thresholding banks on all family 15 models since
+	 * they're not supported there.
+	 */
+	if (c->x86 == 0x15)
+		mc4_misc_thresholding_quirk();
+
 	for (bank = 0; bank < mca_cfg.banks; ++bank) {
 		if (mce_flags.smca)
 			smca_configure(bank, cpu);
diff --git a/arch/x86/kernel/cpu/mce/core.c b/arch/x86/kernel/cpu/mce/core.c
index d0c5416..6063ae2 100644
--- a/arch/x86/kernel/cpu/mce/core.c
+++ b/arch/x86/kernel/cpu/mce/core.c
@@ -1611,35 +1611,6 @@ static int __mcheck_cpu_apply_quirks(struct cpuinfo_x86 *c)
 		if (c->x86 == 0x15 && c->x86_model <= 0xf)
 			mce_flags.overflow_recov = 1;
 
-		/*
-		 * Turn off MC4_MISC thresholding banks on all models since
-		 * they're not supported there.
-		 */
-		if (c->x86 == 0x15) {
-			int i;
-			u64 hwcr;
-			bool need_toggle;
-			u32 msrs[] = {
-				0x00000413, /* MC4_MISC0 */
-				0xc0000408, /* MC4_MISC1 */
-			};
-
-			rdmsrl(MSR_K7_HWCR, hwcr);
-
-			/* McStatusWrEn has to be set */
-			need_toggle = !(hwcr & BIT(18));
-
-			if (need_toggle)
-				wrmsrl(MSR_K7_HWCR, hwcr | BIT(18));
-
-			/* Clear CntP bit safely */
-			for (i = 0; i < ARRAY_SIZE(msrs); i++)
-				msr_clear_bit(msrs[i], 62);
-
-			/* restore old settings */
-			if (need_toggle)
-				wrmsrl(MSR_K7_HWCR, hwcr);
-		}
 	}
 
 	if (c->x86_vendor == X86_VENDOR_INTEL) {
-- 
2.7.4