From ade315d83c1d53b3c6b820134cb16601351810fe Mon Sep 17 00:00:00 2001
From: Paul Mundt <lethal@linux-sh.org>
Date: Tue, 1 Sep 2009 17:45:35 +0900
Subject: [PATCH] sh: Kill off kgdb's magical NMI debouncing.

The kgdb stub has traditionally tied in to the NMI slot, and manually
handled debounce. Now that we have a generic way to do this instead, all
of the stub-specific debounce silliness can be killed off.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
---
 arch/sh/include/asm/kgdb.h     |  3 ---
 arch/sh/kernel/cpu/sh3/entry.S | 31 -------------------------------
 arch/sh/kernel/kgdb.c          |  2 --
 3 files changed, 36 deletions(-)

diff --git a/arch/sh/include/asm/kgdb.h b/arch/sh/include/asm/kgdb.h
index 72704ed725e5..4235e228d921 100644
--- a/arch/sh/include/asm/kgdb.h
+++ b/arch/sh/include/asm/kgdb.h
@@ -30,9 +30,6 @@ static inline void arch_kgdb_breakpoint(void)
 	__asm__ __volatile__ ("trapa #0x3c\n");
 }
 
-/* State info */
-extern char in_nmi;		/* Debounce flag to prevent NMI reentry*/
-
 #define BUFMAX                 2048
 
 #define CACHE_FLUSH_IS_SAFE	1
diff --git a/arch/sh/kernel/cpu/sh3/entry.S b/arch/sh/kernel/cpu/sh3/entry.S
index d1142d365925..0151933e5253 100644
--- a/arch/sh/kernel/cpu/sh3/entry.S
+++ b/arch/sh/kernel/cpu/sh3/entry.S
@@ -53,10 +53,6 @@
  *	syscall #
  *
  */
-#if defined(CONFIG_KGDB)
-NMI_VEC = 0x1c0			! Must catch early for debounce
-#endif
-
 /* Offsets to the stack */
 OFF_R0  =  0		/* Return value. New ABI also arg4 */
 OFF_R1  =  4     	/* New ABI: arg5 */
@@ -71,7 +67,6 @@ OFF_PC  =  (16*4)
 OFF_SR	=  (16*4+8)
 OFF_TRA	=  (16*4+6*4)
 
-
 #define k0	r0
 #define k1	r1
 #define k2	r2
@@ -281,21 +276,12 @@ restore_all:
 6:	or	k0, k2			! Set the IMASK-bits
 	ldc	k2, ssr
 	!
-#if defined(CONFIG_KGDB)
-	! Clear in_nmi
-	mov.l	6f, k0
-	mov	#0, k1
-	mov.b	k1, @k0
-#endif
 	mov	k4, r15
 	rte
 	 nop
 
 	.align	2
 5:	.long	0x00001000	! DSP
-#ifdef CONFIG_KGDB
-6:	.long	in_nmi
-#endif
 7:	.long	0x30000000
 
 ! common exception handler
@@ -487,23 +473,6 @@ ENTRY(save_low_regs)
 !
 	.balign 	512,0,512
 ENTRY(handle_interrupt)
-#if defined(CONFIG_KGDB)
-	mov.l	2f, k2
-	! Debounce (filter nested NMI)
-	mov.l	@k2, k0
-	mov.l	9f, k1
-	cmp/eq	k1, k0
-	bf	11f
-	mov.l	10f, k1
-	tas.b	@k1
-	bt	11f
-	rte
-	 nop
-	.align	2
-9:	.long	NMI_VEC
-10:	.long	in_nmi
-11:
-#endif /* defined(CONFIG_KGDB) */
 	sts	pr, k3		! save original pr value in k3
 	mova	exception_data, k0
 
diff --git a/arch/sh/kernel/kgdb.c b/arch/sh/kernel/kgdb.c
index d29de7864f32..3e532d0d4a5c 100644
--- a/arch/sh/kernel/kgdb.c
+++ b/arch/sh/kernel/kgdb.c
@@ -15,8 +15,6 @@
 #include <linux/io.h>
 #include <asm/cacheflush.h>
 
-char in_nmi = 0;	/* Set during NMI to prevent re-entry */
-
 /* Macros for single step instruction identification */
 #define OPCODE_BT(op)		(((op) & 0xff00) == 0x8900)
 #define OPCODE_BF(op)		(((op) & 0xff00) == 0x8b00)
-- 
2.39.2