[U-Boot] [PATCH v3 01/12] ARM: Factor out reusable psci_cpu_off_common

[Jan Kiszka]

Move parts of sunxi's psci_cpu_off into psci_cpu_off_common, namely
cache disabling and flushing, clrex and the disabling of SMP for the
dying CPU. These steps are apparently generic for ARMv7 and will be
reused for Tegra124 support.

Signed-off-by: Jan Kiszka <jan.kiszka at siemens.com>
---
 arch/arm/cpu/armv7/psci.S       | 71 +++++++++++++++++++++++++++++++++++++++++
 arch/arm/cpu/armv7/sunxi/psci.S | 63 +-----------------------------------
 2 files changed, 72 insertions(+), 62 deletions(-)

diff --git a/arch/arm/cpu/armv7/psci.S b/arch/arm/cpu/armv7/psci.S
index bf11a34..d688607 100644
--- a/arch/arm/cpu/armv7/psci.S
+++ b/arch/arm/cpu/armv7/psci.S
@@ -99,4 +99,75 @@ _smc_psci:
 	pop	{r4-r7, lr}
 	movs	pc, lr			@ Return to the kernel
 
+/* Imported from Linux kernel */
+LENTRY(v7_flush_dcache_all)
+	dmb					@ ensure ordering with previous memory accesses
+	mrc	p15, 1, r0, c0, c0, 1		@ read clidr
+	ands	r3, r0, #0x7000000		@ extract loc from clidr
+	mov	r3, r3, lsr #23			@ left align loc bit field
+	beq	finished			@ if loc is 0, then no need to clean
+	mov	r10, #0				@ start clean at cache level 0
+flush_levels:
+	add	r2, r10, r10, lsr #1		@ work out 3x current cache level
+	mov	r1, r0, lsr r2			@ extract cache type bits from clidr
+	and	r1, r1, #7			@ mask of the bits for current cache only
+	cmp	r1, #2				@ see what cache we have at this level
+	blt	skip				@ skip if no cache, or just i-cache
+	mrs     r9, cpsr			@ make cssr&csidr read atomic
+	mcr	p15, 2, r10, c0, c0, 0		@ select current cache level in cssr
+	isb					@ isb to sych the new cssr&csidr
+	mrc	p15, 1, r1, c0, c0, 0		@ read the new csidr
+	msr     cpsr_c, r9
+	and	r2, r1, #7			@ extract the length of the cache lines
+	add	r2, r2, #4			@ add 4 (line length offset)
+	ldr	r4, =0x3ff
+	ands	r4, r4, r1, lsr #3		@ find maximum number on the way size
+	clz	r5, r4				@ find bit position of way size increment
+	ldr	r7, =0x7fff
+	ands	r7, r7, r1, lsr #13		@ extract max number of the index size
+loop1:
+	mov	r9, r7				@ create working copy of max index
+loop2:
+	orr	r11, r10, r4, lsl r5		@ factor way and cache number into r11
+	orr	r11, r11, r9, lsl r2		@ factor index number into r11
+	mcr	p15, 0, r11, c7, c14, 2		@ clean & invalidate by set/way
+	subs	r9, r9, #1			@ decrement the index
+	bge	loop2
+	subs	r4, r4, #1			@ decrement the way
+	bge	loop1
+skip:
+	add	r10, r10, #2			@ increment cache number
+	cmp	r3, r10
+	bgt	flush_levels
+finished:
+	mov	r10, #0				@ swith back to cache level 0
+	mcr	p15, 2, r10, c0, c0, 0		@ select current cache level in cssr
+	dsb	st
+	isb
+	bx	lr
+ENDPROC(v7_flush_dcache_all)
+
+ENTRY(psci_cpu_off_common)
+	push	{lr}
+
+	mrc	p15, 0, r0, c1, c0, 0		@ SCTLR
+	bic	r0, r0, #(1 << 2)		@ Clear C bit
+	mcr	p15, 0, r0, c1, c0, 0		@ SCTLR
+	isb
+	dsb
+
+	bl	v7_flush_dcache_all
+
+	clrex					@ Why???
+
+	mrc	p15, 0, r0, c1, c0, 1		@ ACTLR
+	bic	r0, r0, #(1 << 6)		@ Clear SMP bit
+	mcr	p15, 0, r0, c1, c0, 1		@ ACTLR
+	isb
+	dsb
+
+	pop	{lr}
+	bx	lr
+ENDPROC(psci_cpu_off_common)
+
 	.popsection
diff --git a/arch/arm/cpu/armv7/sunxi/psci.S b/arch/arm/cpu/armv7/sunxi/psci.S
index 5be497b..6785fdd 100644
--- a/arch/arm/cpu/armv7/sunxi/psci.S
+++ b/arch/arm/cpu/armv7/sunxi/psci.S
@@ -199,53 +199,6 @@ psci_cpu_on:
 _target_pc:
 	.word	0
 
-/* Imported from Linux kernel */
-v7_flush_dcache_all:
-	dmb					@ ensure ordering with previous memory accesses
-	mrc	p15, 1, r0, c0, c0, 1		@ read clidr
-	ands	r3, r0, #0x7000000		@ extract loc from clidr
-	mov	r3, r3, lsr #23			@ left align loc bit field
-	beq	finished			@ if loc is 0, then no need to clean
-	mov	r10, #0				@ start clean at cache level 0
-flush_levels:
-	add	r2, r10, r10, lsr #1		@ work out 3x current cache level
-	mov	r1, r0, lsr r2			@ extract cache type bits from clidr
-	and	r1, r1, #7			@ mask of the bits for current cache only
-	cmp	r1, #2				@ see what cache we have at this level
-	blt	skip				@ skip if no cache, or just i-cache
-	mrs     r9, cpsr			@ make cssr&csidr read atomic
-	mcr	p15, 2, r10, c0, c0, 0		@ select current cache level in cssr
-	isb					@ isb to sych the new cssr&csidr
-	mrc	p15, 1, r1, c0, c0, 0		@ read the new csidr
-	msr     cpsr_c, r9
-	and	r2, r1, #7			@ extract the length of the cache lines
-	add	r2, r2, #4			@ add 4 (line length offset)
-	ldr	r4, =0x3ff
-	ands	r4, r4, r1, lsr #3		@ find maximum number on the way size
-	clz	r5, r4				@ find bit position of way size increment
-	ldr	r7, =0x7fff
-	ands	r7, r7, r1, lsr #13		@ extract max number of the index size
-loop1:
-	mov	r9, r7				@ create working copy of max index
-loop2:
-	orr	r11, r10, r4, lsl r5		@ factor way and cache number into r11
-	orr	r11, r11, r9, lsl r2		@ factor index number into r11
-	mcr	p15, 0, r11, c7, c14, 2		@ clean & invalidate by set/way
-	subs	r9, r9, #1			@ decrement the index
-	bge	loop2
-	subs	r4, r4, #1			@ decrement the way
-	bge	loop1
-skip:
-	add	r10, r10, #2			@ increment cache number
-	cmp	r3, r10
-	bgt	flush_levels
-finished:
-	mov	r10, #0				@ swith back to cache level 0
-	mcr	p15, 2, r10, c0, c0, 0		@ select current cache level in cssr
-	dsb	st
-	isb
-	bx	lr
-
 _sunxi_cpu_entry:
 	@ Set SMP bit
 	mrc	p15, 0, r0, c1, c0, 1
@@ -262,21 +215,7 @@ _sunxi_cpu_entry:
 
 .globl	psci_cpu_off
 psci_cpu_off:
-	mrc	p15, 0, r0, c1, c0, 0		@ SCTLR
-	bic	r0, r0, #(1 << 2)		@ Clear C bit
-	mcr	p15, 0, r0, c1, c0, 0		@ SCTLR
-	isb
-	dsb
-
-	bl	v7_flush_dcache_all
-
-	clrex					@ Why???
-
-	mrc	p15, 0, r0, c1, c0, 1		@ ACTLR
-	bic	r0, r0, #(1 << 6)		@ Clear SMP bit
-	mcr	p15, 0, r0, c1, c0, 1		@ ACTLR
-	isb
-	dsb
+	bl	psci_cpu_off_common
 
 	@ Ask CPU0 to pull the rug...
 	movw	r0, #(GICD_BASE & 0xffff)
-- 
2.1.4