Check whether the TLB operations need broadcasting on SMP systems
ARMv7 SMP hardware can handle the TLB maintenance operations
broadcasting in hardware so that the software can avoid the costly IPIs.
This patch adds the necessary checks (the MMFR3 CPUID register) to avoid
the broadcasting if already supported by the hardware.
(this patch is based on the work done by Tony Thompson @ ARM)
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
diff --git a/arch/arm/mm/proc-v7.S b/arch/arm/mm/proc-v7.S
index 3397f1e..c3f7375 100644
--- a/arch/arm/mm/proc-v7.S
+++ b/arch/arm/mm/proc-v7.S
@@ -176,8 +176,8 @@
*/
__v7_setup:
#ifdef CONFIG_SMP
- mrc p15, 0, r0, c1, c0, 1 @ Enable SMP/nAMP mode
- orr r0, r0, #(0x1 << 6)
+ mrc p15, 0, r0, c1, c0, 1 @ Enable SMP/nAMP mode and
+ orr r0, r0, #(1 << 6) | (1 << 0) @ TLB ops broadcasting
mcr p15, 0, r0, c1, c0, 1
#endif
adr r12, __v7_setup_stack @ the local stack
diff --git a/arch/arm/mm/tlb-v7.S b/arch/arm/mm/tlb-v7.S
index b637e73..a26a605 100644
--- a/arch/arm/mm/tlb-v7.S
+++ b/arch/arm/mm/tlb-v7.S
@@ -42,9 +42,11 @@
mov r1, r1, lsl #PAGE_SHIFT
vma_vm_flags r2, r2 @ get vma->vm_flags
1:
- mcr p15, 0, r0, c8, c6, 1 @ TLB invalidate D MVA (was 1)
- tst r2, #VM_EXEC @ Executable area ?
- mcrne p15, 0, r0, c8, c5, 1 @ TLB invalidate I MVA (was 1)
+#ifdef CONFIG_SMP
+ mcr p15, 0, r0, c8, c3, 1 @ TLB invalidate U MVA (shareable)
+#else
+ mcr p15, 0, r0, c8, c7, 1 @ TLB invalidate U MVA
+#endif
add r0, r0, #PAGE_SZ
cmp r0, r1
blo 1b
@@ -69,8 +71,11 @@
mov r0, r0, lsl #PAGE_SHIFT
mov r1, r1, lsl #PAGE_SHIFT
1:
- mcr p15, 0, r0, c8, c6, 1 @ TLB invalidate D MVA
- mcr p15, 0, r0, c8, c5, 1 @ TLB invalidate I MVA
+#ifdef CONFIG_SMP
+ mcr p15, 0, r0, c8, c3, 1 @ TLB invalidate U MVA (shareable)
+#else
+ mcr p15, 0, r0, c8, c7, 1 @ TLB invalidate U MVA
+#endif
add r0, r0, #PAGE_SZ
cmp r0, r1
blo 1b
@@ -87,5 +92,5 @@
ENTRY(v7wbi_tlb_fns)
.long v7wbi_flush_user_tlb_range
.long v7wbi_flush_kern_tlb_range
- .long v6wbi_tlb_flags
+ .long v7wbi_tlb_flags
.size v7wbi_tlb_fns, . - v7wbi_tlb_fns