linux-kernel - [PATCH 1/6] x86: apic - unify clear_local

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Date:	Sat, 16 Aug 2008 23:21:50 +0400
From:	Cyrill Gorcunov <gorcunov@...il.com>
To:	mingo@...e.hu, hpa@...or.com, tglx@...utronix.de,
	macro@...ux-mips.org, linux-kernel@...r.kernel.org
Cc:	Cyrill Gorcunov <gorcunov@...il.com>
Subject: [PATCH 1/6] x86: apic - unify clear_local_APIC

- Remove redundant masking of APIC_LVTTHMR register in apic_32.c

- Add masking of APIC_LVTTHMR register to apic_64.c. We use a bit
  complicated #ifdef here: CONFIG_X86_MCE_P4THERMAL is 32bit specific
  and X86_MCE_INTEL is 64bit specific so the appropriate config variable
  will be set by Kconfig.

- the APIC_ESR register clearing in apic_64.c now uses not straightforward
  way but this is allowed tradeoff.

Signed-off-by: Cyrill Gorcunov <gorcunov@...il.com>
---
 arch/x86/kernel/apic_32.c |    6 +-----
 arch/x86/kernel/apic_64.c |   17 +++++++++++++++--
 2 files changed, 16 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kernel/apic_32.c b/arch/x86/kernel/apic_32.c
index 16d9721..3131603 100644
--- a/arch/x86/kernel/apic_32.c
+++ b/arch/x86/kernel/apic_32.c
@@ -754,7 +754,7 @@ void clear_local_APIC(void)
 	}
 
 	/* lets not touch this if we didn't frob it */
-#ifdef CONFIG_X86_MCE_P4THERMAL
+#if defined(CONFIG_X86_MCE_P4THERMAL) || defined(X86_MCE_INTEL)
 	if (maxlvt >= 5) {
 		v = apic_read(APIC_LVTTHMR);
 		apic_write(APIC_LVTTHMR, v | APIC_LVT_MASKED);
@@ -771,10 +771,6 @@ void clear_local_APIC(void)
 	if (maxlvt >= 4)
 		apic_write(APIC_LVTPC, APIC_LVT_MASKED);
 
-#ifdef CONFIG_X86_MCE_P4THERMAL
-	if (maxlvt >= 5)
-		apic_write(APIC_LVTTHMR, APIC_LVT_MASKED);
-#endif
 	/* Integrated APIC (!82489DX) ? */
 	if (lapic_is_integrated()) {
 		if (maxlvt > 3)
diff --git a/arch/x86/kernel/apic_64.c b/arch/x86/kernel/apic_64.c
index 99d18b8..d834b75 100644
--- a/arch/x86/kernel/apic_64.c
+++ b/arch/x86/kernel/apic_64.c
@@ -630,6 +630,13 @@ void clear_local_APIC(void)
 		apic_write(APIC_LVTPC, v | APIC_LVT_MASKED);
 	}
 
+	/* lets not touch this if we didn't frob it */
+#if defined(CONFIG_X86_MCE_P4THERMAL) || defined(X86_MCE_INTEL)
+	if (maxlvt >= 5) {
+		v = apic_read(APIC_LVTTHMR);
+		apic_write(APIC_LVTTHMR, v | APIC_LVT_MASKED);
+	}
+#endif
 	/*
 	 * Clean APIC state for other OSs:
 	 */
@@ -640,8 +647,14 @@ void clear_local_APIC(void)
 		apic_write(APIC_LVTERR, APIC_LVT_MASKED);
 	if (maxlvt >= 4)
 		apic_write(APIC_LVTPC, APIC_LVT_MASKED);
-	apic_write(APIC_ESR, 0);
-	apic_read(APIC_ESR);
+
+	/* Integrated APIC (!82489DX) ? */
+	if (lapic_is_integrated()) {
+		if (maxlvt > 3)
+			/* Clear ESR due to Pentium errata 3AP and 11AP */
+			apic_write(APIC_ESR, 0);
+		apic_read(APIC_ESR);
+	}
 }
 
 /**
-- 
1.6.0.rc1.34.g0fe8c

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