* arm/crt0.S: Support armv6-m processors in libgloss.

* arm/swi.h: Likewise.
	* arm/trap.S: Likewise.
	* arm/redboot-crt0.S: Likewise.
	* arm/linux-crt0.c: Likewise.
	* arm/arm.h: New.

libgloss/arm/redboot-crt0.S

@@ -1,3 +1,4 @@
+#include "arm.h"
 	
     .file   "crt0.S"
 	
@@ -11,14 +12,14 @@
 #endif
 
     .text
+	.syntax unified
      /* Setup the assembly entry point.  */
-#ifdef __thumb2__
+#ifdef THUMB_V7_V6M
 .macro FUNC_START name
 	.global \name
 	.thumb_func
 \name:
 .endm
-	.syntax unified
 	.thumb
 #else
 .macro FUNC_START name
@@ -29,11 +30,15 @@
 #endif
 	FUNC_START SYM_NAME(start)
 	FUNC_START SYM_NAME(_start)
+    /* Unnecessary to set fp for v6-m/v7-m, which don't support
+       ARM state.  */
+#ifndef THUMB_V7M_V6M
 	mov	fp, #0	/* Null frame pointer.  */
-	mov	r7, #0	/* Null frame pointer for Thumb.  */
+#endif
+	movs	r7, #0	/* Null frame pointer for Thumb.  */
 
 	/* Enable interrupts for gdb debugging.  */
-#ifdef __thumb2__
+#ifdef THUMB_V7_V6M
 	cpsie if
 #else
 	mrs    r0, cpsr
@@ -41,10 +46,10 @@
 	msr    cpsr, r0
 #endif
 	
-	mov 	a2, #0			/* Second arg: fill value.  */
+	movs 	a2, #0			/* Second arg: fill value.  */
 	ldr	a1, .LC1		/* First arg: start of memory block.  */
 	ldr	a3, .LC2	
-	sub	a3, a3, a1		/* Third arg: length of block.  */
+	subs	a3, a3, a1		/* Third arg: length of block.  */
 
 #ifdef	GCRT0
 	/* Zero out the bss without using memset. 
@@ -62,7 +67,8 @@
 	/* Nothing to left to clear.  */
 #endif
 
-#if defined(__thumb__) && !defined(__thumb2__)	/* Enter Thumb mode. */
+#if defined(__thumb__) && !defined(THUMB_V7_V6M)
+	/* Enter Thumb mode. */
 	add	a4, pc, #1	/* Get the address of the Thumb block.  */
 	bx	a4		/* Go there and start Thumb decoding.   */
 
@@ -76,7 +82,7 @@ __change_mode:
 	bl	SYM_NAME(memset)
 #endif
 	bl	SYM_NAME(__get_memtop)
-	sub	r0, r0, #32
+	subs	r0, r0, #32
 	mov	sp, r0
 
 #ifdef __USES_INITFINI__
@@ -89,7 +95,7 @@ __change_mode:
 	bl	SYM_NAME (_init)
 #endif	
 
-	mov 	a1, #0
+	movs 	a1, #0
 	ldr	a2, .LC3
 	mov	a3, a2
 	bl	SYM_NAME(main)