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-rw-r--r--arch/arm/kernel/head.S59
1 files changed, 38 insertions, 21 deletions
diff --git a/arch/arm/kernel/head.S b/arch/arm/kernel/head.S
index dd6b369ac69c..c0225da3fb21 100644
--- a/arch/arm/kernel/head.S
+++ b/arch/arm/kernel/head.S
@@ -85,10 +85,17 @@ ENTRY(stext)
 	mrc	p15, 0, r9, c0, c0		@ get processor id
 	bl	__lookup_processor_type		@ r5=procinfo r9=cpuid
 	movs	r10, r5				@ invalid processor (r5=0)?
+ THUMB( it	eq )		@ force fixup-able long branch encoding
 	beq	__error_p			@ yes, error 'p'
 	bl	__lookup_machine_type		@ r5=machinfo
 	movs	r8, r5				@ invalid machine (r5=0)?
+ THUMB( it	eq )		@ force fixup-able long branch encoding
 	beq	__error_a			@ yes, error 'a'
+
+	/*
+	 * r1 = machine no, r2 = atags,
+	 * r8 = machinfo, r9 = cpuid, r10 = procinfo
+	 */
 	bl	__vet_atags
 #ifdef CONFIG_SMP_ON_UP
 	bl	__fixup_smp
@@ -262,6 +269,7 @@ __create_page_tables:
 	mov	pc, lr
 ENDPROC(__create_page_tables)
 	.ltorg
+	.align
 __enable_mmu_loc:
 	.long	.
 	.long	__enable_mmu
@@ -282,6 +290,7 @@ ENTRY(secondary_startup)
 	bl	__lookup_processor_type
 	movs	r10, r5				@ invalid processor?
 	moveq	r0, #'p'			@ yes, error 'p'
+ THUMB( it	eq )		@ force fixup-able long branch encoding
 	beq	__error_p
 
 	/*
@@ -308,6 +317,8 @@ ENTRY(__secondary_switched)
 	b	secondary_start_kernel
 ENDPROC(__secondary_switched)
 
+	.align
+
 	.type	__secondary_data, %object
 __secondary_data:
 	.long	.
@@ -381,38 +392,44 @@ ENDPROC(__turn_mmu_on)
 
 #ifdef CONFIG_SMP_ON_UP
 __fixup_smp:
-	mov	r7, #0x00070000
-	orr	r6, r7, #0xff000000	@ mask 0xff070000
-	orr	r7, r7, #0x41000000	@ val 0x41070000
-	and	r0, r9, r6
-	teq	r0, r7			@ ARM CPU and ARMv6/v7?
+	and	r3, r9, #0x000f0000	@ architecture version
+	teq	r3, #0x000f0000		@ CPU ID supported?
 	bne	__fixup_smp_on_up	@ no, assume UP
 
-	orr	r6, r6, #0x0000ff00
-	orr	r6, r6, #0x000000f0	@ mask 0xff07fff0
-	orr	r7, r7, #0x0000b000
-	orr	r7, r7, #0x00000020	@ val 0x4107b020
-	and	r0, r9, r6
-	teq	r0, r7			@ ARM 11MPCore?
+	bic	r3, r9, #0x00ff0000
+	bic	r3, r3, #0x0000000f	@ mask 0xff00fff0
+	mov	r4, #0x41000000
+	orr	r4, r4, #0x0000b000
+	orr	r4, r4, #0x00000020	@ val 0x4100b020
+	teq	r3, r4			@ ARM 11MPCore?
 	moveq	pc, lr			@ yes, assume SMP
 
 	mrc	p15, 0, r0, c0, c0, 5	@ read MPIDR
-	tst	r0, #1 << 31
-	movne	pc, lr			@ bit 31 => SMP
+	and	r0, r0, #0xc0000000	@ multiprocessing extensions and
+	teq	r0, #0x80000000		@ not part of a uniprocessor system?
+	moveq	pc, lr			@ yes, assume SMP
 
 __fixup_smp_on_up:
 	adr	r0, 1f
-	ldmia	r0, {r3, r6, r7}
+	ldmia	r0, {r3 - r5}
 	sub	r3, r0, r3
-	add	r6, r6, r3
-	add	r7, r7, r3
-2:	cmp	r6, r7
-	ldmia	r6!, {r0, r4}
-	strlo	r4, [r0, r3]
-	blo	2b
-	mov	pc, lr
+	add	r4, r4, r3
+	add	r5, r5, r3
+2:	cmp	r4, r5
+	movhs	pc, lr
+	ldmia	r4!, {r0, r6}
+ ARM(	str	r6, [r0, r3]	)
+ THUMB(	add	r0, r0, r3	)
+#ifdef __ARMEB__
+ THUMB(	mov	r6, r6, ror #16	)	@ Convert word order for big-endian.
+#endif
+ THUMB(	strh	r6, [r0], #2	)	@ For Thumb-2, store as two halfwords
+ THUMB(	mov	r6, r6, lsr #16	)	@ to be robust against misaligned r3.
+ THUMB(	strh	r6, [r0]	)
+	b	2b
 ENDPROC(__fixup_smp)
 
+	.align
 1:	.word	.
 	.word	__smpalt_begin
 	.word	__smpalt_end