patch-2.1.37 linux/arch/sparc64/kernel/etrap.S

• Lines: 134
• Date: Mon May 12 10:35:39 1997
• Orig file: v2.1.36/linux/arch/sparc64/kernel/etrap.S
• Orig date: Wed Apr 23 19:01:16 1997

diff -u --recursive --new-file v2.1.36/linux/arch/sparc64/kernel/etrap.S linux/arch/sparc64/kernel/etrap.S
@@ -1,7 +1,7 @@
-/* $Id: etrap.S,v 1.11 1997/04/14 17:04:45 jj Exp $
+/* $Id: etrap.S,v 1.12 1997/04/28 14:57:07 davem Exp $
  * etrap.S: Preparing for entry into the kernel on Sparc V9.
  *
- * Copyright (C) 1996 David S. Miller (davem@caip.rutgers.edu)
+ * Copyright (C) 1996, 1997 David S. Miller (davem@caip.rutgers.edu)
  * Copyright (C) 1997 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
  */
 
@@ -11,24 +11,28 @@
 #include <asm/spitfire.h>
 #include <asm/head.h>
 
-/* We assume that pstate, when entering this, has AG and IE bits set, MG and IG clear */
+	/* We assume that pstate, when entering this, has AG and
+	 * IE bits set, MG and IG clear.
+	 *
+	 * We also guarentee for caller that AG %g4 and %g5 will have
+	 * their values preserved and left in %l4 and %l5 respectively
+	 * for him (fault handling needs this).
+	 */
 
 	.text
 	.align	32
 	.globl	etrap, etrap_irq
 etrap:
-	rdpr		%pil, %g4
+	rdpr		%pil, %g2
 etrap_irq:
 	rdpr		%tstate, %g1
-	sllx		%g4, 20, %g4
-	rdpr		%tpc, %g2
-	or		%g1, %g4, %g1
-	rdpr		%tnpc, %g3
+	sllx		%g2, 20, %g2
+	or		%g1, %g2, %g1
 
 	/* What happens more often? etrap when already in priv or from userland? */
 	andcc		%g1, TSTATE_PRIV, %g0
 	bne,a,pn	%xcc, 1f
-	 sub		%sp, REGWIN_SZ + TRACEREG_SZ - STACK_BIAS, %g5
+	 sub		%sp, REGWIN_SZ + TRACEREG_SZ - STACK_BIAS, %g2
 
 	/* Just when going from userland to privileged mode,
 	 * we have to change this stuff.
@@ -38,41 +42,47 @@
 	 * trap level until PRIMARY_CONTEXT is set to zero, else
 	 * we fall out of NUCLEUS too soon and crash hard.
 	 */
-	rdpr		%wstate, %g5
-	mov		PRIMARY_CONTEXT, %g7
-	ldxa		[%g7] ASI_DMMU, %g4
-	mov		SECONDARY_CONTEXT, %g6
-	stxa		%g0, [%g7] ASI_DMMU
-	stxa		%g4, [%g6] ASI_DMMU
-	wrpr		%g0, 0x0, %tl
-
-	sll		%g5, 3, %g5
-	sethi		%uhi(KERNBASE), %g4
-	or		%g4, %ulo(KERNBASE), %g4
-	sethi		%hi(current_set), %g6
-	or		%g6, %lo(current_set), %g6
-	sllx		%g4, 32, %g4
-	wrpr		%g5, %wstate
-	rdpr		%canrestore, %g5
-	ldx		[%g6 + %g4], %g6
+	mov		PRIMARY_CONTEXT, %g1
+	ldxa		[%g1] ASI_DMMU, %g2
+	stxa		%g0, [%g1] ASI_DMMU
+
+	mov		SECONDARY_CONTEXT, %g1
+	stxa		%g2, [%g1] ASI_DMMU
+
+	rdpr		%wstate, %g1
+	sll		%g1, 3, %g1
+	wrpr		%g1, %wstate
+
+	sethi		%uhi(KERNBASE), %g2
+	or		%g2, %ulo(KERNBASE), %g2
+	sethi		%hi(current_set), %g1
+	or		%g1, %lo(current_set), %g1
+	sllx		%g2, 32, %g2
+	ldx		[%g1 + %g2], %g1
 #ifdef __SMP__
 /* FIXME: Fix the above insn for SMP */
 #endif
+	rdpr		%canrestore, %g2
 	wrpr		%g0, 0, %canrestore
-	wrpr		%g5, 0, %otherwin
-	ba,pt		%xcc, 2f
-	 ldx		[%g6 + AOFF_task_saved_kernel_stack], %g5
+	wrpr		%g2, 0, %otherwin
+
+	ldx		[%g1 + AOFF_task_saved_kernel_stack], %g2
 1:
+	stx		%g1, [%g2 + REGWIN_SZ + PT_V9_TSTATE]
+	rdpr		%tpc, %g1
+	rdpr		%tnpc, %g3
+	stx		%g1, [%g2 + REGWIN_SZ + PT_V9_TPC]
+	rd		%y, %g1
+	stx		%g3, [%g2 + REGWIN_SZ + PT_V9_TNPC]
+	stx		%g1, [%g2 + REGWIN_SZ + PT_V9_Y]
+
 	wrpr		%g0, 0x0, %tl
-2:
-	rd		%y, %g4
-	stx		%g1, [%g5 + REGWIN_SZ + PT_V9_TSTATE]
-	stx		%g2, [%g5 + REGWIN_SZ + PT_V9_TPC]
-	stx		%g3, [%g5 + REGWIN_SZ + PT_V9_TNPC]
-	stx		%g4, [%g5 + REGWIN_SZ + PT_V9_Y]
+
 	rdpr		%pstate, %g1
-	save		%g5, -STACK_BIAS, %sp
+	save		%g2, -STACK_BIAS, %sp
 	mov		%g1, %l1
+	mov		%g4, %l4
+	mov		%g5, %l5
 	mov		%g7, %l2
 	wrpr		%l1, PSTATE_AG, %pstate
 	stx		%g1, [%sp + STACK_BIAS + REGWIN_SZ + PT_V9_G1]
@@ -104,11 +114,6 @@
 
 	.globl	etraptl1
 etraptl1:
-	rdpr	%tl, %g4
 	rdpr	%tstate, %g1
-	sub	%g4, 1, %g4
-	rdpr	%tpc, %g2
-	rdpr	%tnpc, %g3
-	wrpr	%g4, 0x0, %tl
 	ba,pt	%xcc, 1b
-	 sub	%sp, REGWIN_SZ + TRACEREG_SZ - STACK_BIAS, %g5
+	 sub	%sp, REGWIN_SZ + TRACEREG_SZ - STACK_BIAS, %g2