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x86, nmi: Define a name for NMI control port

PATCH RESEND In review Cyrill Gorcunov 2 participants 4 messages Mar 2, 2011 x86

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Cyrill Gorcunov

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#0 lore raw

PATCH RESEND 1/2 x86, nmi: Define a name for NMI control port

Also add a comment anout why we need in-out operations.

Signed-off-by Cyrill Gorcunov <[email protected]>

---

Ingo I hope this time I've resolved MUA space injection.

 arch/x86/include/asm/mach_traps.h |   18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)
arch/x86/include/asm/mach_traps.h +13 -5
Index: linux-2.6.git/arch/x86/include/asm/mach_traps.h
=====================================================================
@@ -8,6 +8,7 @@
 #include <asm/mc146818rtc.h>
 
 #define NMI_REASON_PORT		0x61
+#define NMI_ENABLE_PORT		0x70 /* Real-Time Clock Address Register as well */
 
 #define NMI_REASON_SERR		0x80
 #define NMI_REASON_IOCHK	0x40

@@ -30,12 +31,19 @@ static inline void reassert_nmi(void)
 		old_reg = current_lock_cmos_reg();
 	else
 		lock_cmos(0); /* register doesn't matter here */
-	outb(0x8f, 0x70);
-	inb(0x71);		/* dummy */
-	outb(0x0f, 0x70);
-	inb(0x71);		/* dummy */
+
+	/*
+	 * This will cause the NMI output to transition low
+	 * then high if there are any pending NMI sources. The
+	 * CPU's NMI input logic will then register a new NMI.
+	 */
+	outb(0x8f, NMI_ENABLE_PORT);
+	inb(0x71);	/* dummy */
+	outb(0x0f, NMI_ENABLE_PORT);
+	inb(0x71);	/* dummy */
+
 	if (old_reg >= 0)
-		outb(old_reg, 0x70);
+		outb(old_reg, NMI_ENABLE_PORT);
 	else
 		unlock_cmos();
 }
Signature · 1 line
    Cyrill
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#1 lore raw
Commit-ID:  0f5dbad5ecab0921911966e857eab408ef32163c
Gitweb:     http://git.kernel.org/tip/0f5dbad5ecab0921911966e857eab408ef32163c
Author:     Cyrill Gorcunov <[email protected]>
AuthorDate: Wed, 2 Mar 2011 18:32:30 +0300
Committer:  Ingo Molnar <[email protected]>
CommitDate: Wed, 2 Mar 2011 16:44:44 +0100

x86, nmi: Define a name for NMI control port

Also add a comment about why we need in/out operations.

Signed-off-by Cyrill Gorcunov <[email protected]>
Cc Don Zickus <[email protected]>
Cc Huang Ying <[email protected]>

LKML-Reference: <[email protected]>

Signed-off-by Ingo Molnar <[email protected]>
---
 arch/x86/include/asm/mach_traps.h |   18 +++++++++++++-----
 1 files changed, 13 insertions(+), 5 deletions(-)
arch/x86/include/asm/mach_traps.h +13 -5
index 72a8b52..7775deb 100644
@@ -8,6 +8,7 @@
 #include <asm/mc146818rtc.h>
 
 #define NMI_REASON_PORT		0x61
+#define NMI_ENABLE_PORT		0x70 /* Real-Time Clock Address Register as well */
 
 #define NMI_REASON_SERR		0x80
 #define NMI_REASON_IOCHK	0x40

@@ -30,12 +31,19 @@ static inline void reassert_nmi(void)
 		old_reg = current_lock_cmos_reg();
 	else
 		lock_cmos(0); /* register doesn't matter here */
-	outb(0x8f, 0x70);
-	inb(0x71);		/* dummy */
-	outb(0x0f, 0x70);
-	inb(0x71);		/* dummy */
+
+	/*
+	 * This will cause the NMI output to transition low
+	 * then high if there are any pending NMI sources. The
+	 * CPU's NMI input logic will then register a new NMI.
+	 */
+	outb(0x8f, NMI_ENABLE_PORT);
+	inb(0x71);	/* dummy */
+	outb(0x0f, NMI_ENABLE_PORT);
+	inb(0x71);	/* dummy */
+
 	if (old_reg >= 0)
-		outb(old_reg, 0x70);
+		outb(old_reg, NMI_ENABLE_PORT);
 	else
 		unlock_cmos();
 }
#2 lore raw
In reply to Cyrill Gorcunov
Quoted 23 lines · Cyrill Gorcunov

Also add a comment anout why we need in-out operations.

Signed-off-by Cyrill Gorcunov <[email protected]>

---

Ingo I hope this time I've resolved MUA space injection.

 arch/x86/include/asm/mach_traps.h |   18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

Index: linux-2.6.git/arch/x86/include/asm/mach_traps.h
=====================================================================

arch/x86/include/asm/mach_traps.h +1 -0
@@ -8,6 +8,7 @@
 #include <asm/mc146818rtc.h>
 
 #define NMI_REASON_PORT		0x61
+#define NMI_ENABLE_PORT		0x70 /* Real-Time Clock Address Register as well */
 
 #define NMI_REASON_SERR		0x80
 #define NMI_REASON_IOCHK	0x40

arch/x86/include/asm/mach_traps.h static inline void reassert_nmi(void) · line 34

Quoted 5 lines
arch/x86/include/asm/mach_traps.h +0 -2
@@ -30,12 +31,19 @@ static inline void reassert_nmi(void)
 		old_reg = current_lock_cmos_reg();
 	else
 		lock_cmos(0); /* register doesn't matter here */
-	outb(0x8f, 0x70);
-	inb(0x71);		/* dummy */

I was wondering if 0x71 should get a name change too. Then again I can't find the Intel doc that tells me what 0x70 is either (I remember seeing it somewhere).

Cheers,
Don

author
#3 lore raw
Quoted 34 lines · Don Zickus
Quoted 23 lines · Cyrill Gorcunov

Also add a comment anout why we need in-out operations.

Signed-off-by Cyrill Gorcunov <[email protected]>

---

Ingo I hope this time I've resolved MUA space injection.

 arch/x86/include/asm/mach_traps.h |   18 +++++++++++++-----
 1 file changed, 13 insertions(+), 5 deletions(-)

Index: linux-2.6.git/arch/x86/include/asm/mach_traps.h
=====================================================================

arch/x86/include/asm/mach_traps.h +1 -0
@@ -8,6 +8,7 @@
 #include <asm/mc146818rtc.h>
 
 #define NMI_REASON_PORT		0x61
+#define NMI_ENABLE_PORT		0x70 /* Real-Time Clock Address Register as well */
 
 #define NMI_REASON_SERR		0x80
 #define NMI_REASON_IOCHK	0x40

arch/x86/include/asm/mach_traps.h static inline void reassert_nmi(void) · line 34

Quoted 5 lines
arch/x86/include/asm/mach_traps.h +0 -2
@@ -30,12 +31,19 @@ static inline void reassert_nmi(void)
 		old_reg = current_lock_cmos_reg();
 	else
 		lock_cmos(0); /* register doesn't matter here */
-	outb(0x8f, 0x70);
-	inb(0x71);		/* dummy */

I was wondering if 0x71 should get a name change too. Then again I can't find the Intel doc that tells me what 0x70 is either (I remember seeing it somewhere).

Quoted 2 lines

Cheers,
Don

Well, me specs are on another machine (which I didn't copied back yet :) but
if my memory doesn't betray me it can be found in ICH specification. For 0x71 i simply don't remember how it's named in spec but it stands for RTC ram target register iirc.

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    Cyrill