ARM: invalidate L1 before enabling coherency
We must invalidate the L1 cache before enabling coherency, otherwise
secondary CPUs can inject invalid cache lines into the coherent CPU
cluster, which could then be migrated to other CPUs. This fixes a
recent regression with SoCFPGA randomly failing to boot.
Fixes: 02b4e2756e01 ("ARM: v7 setup function should invalidate L1 cache")
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
diff --git a/arch/arm/mm/proc-v7.S b/arch/arm/mm/proc-v7.S
index 0716bbe..de2b246 100644
--- a/arch/arm/mm/proc-v7.S
+++ b/arch/arm/mm/proc-v7.S
@@ -274,7 +274,10 @@
__v7_b15mp_setup:
__v7_ca17mp_setup:
mov r10, #0
-1:
+1: adr r12, __v7_setup_stack @ the local stack
+ stmia r12, {r0-r5, lr} @ v7_invalidate_l1 touches r0-r6
+ bl v7_invalidate_l1
+ ldmia r12, {r0-r5, lr}
#ifdef CONFIG_SMP
ALT_SMP(mrc p15, 0, r0, c1, c0, 1)
ALT_UP(mov r0, #(1 << 6)) @ fake it for UP
@@ -283,7 +286,7 @@
orreq r0, r0, r10 @ Enable CPU-specific SMP bits
mcreq p15, 0, r0, c1, c0, 1
#endif
- b __v7_setup
+ b __v7_setup_cont
/*
* Errata:
@@ -413,10 +416,11 @@
__v7_setup:
adr r12, __v7_setup_stack @ the local stack
- stmia r12, {r0-r5, r7, r9, r11, lr}
+ stmia r12, {r0-r5, lr} @ v7_invalidate_l1 touches r0-r6
bl v7_invalidate_l1
- ldmia r12, {r0-r5, r7, r9, r11, lr}
+ ldmia r12, {r0-r5, lr}
+__v7_setup_cont:
and r0, r9, #0xff000000 @ ARM?
teq r0, #0x41000000
bne __errata_finish
@@ -480,7 +484,7 @@
.align 2
__v7_setup_stack:
- .space 4 * 11 @ 11 registers
+ .space 4 * 7 @ 12 registers
__INITDATA