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>

2 files changed, 13 insertions, 8 deletions

diff --git a/arch/arm/mm/proc-v7.S b/arch/arm/mm/proc-v7.S
index 3397f1e64d76..c3f737516836 100644
--- a/arch/arm/mm/proc-v7.S
+++ b/arch/arm/mm/proc-v7.S
@@ -176,8 +176,8 @@ cpu_v7_name:
  */
 __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 b637e7380ab7..a26a605b73bd 100644
--- a/arch/arm/mm/tlb-v7.S
+++ b/arch/arm/mm/tlb-v7.S
@@ -42,9 +42,11 @@ ENTRY(v7wbi_flush_user_tlb_range)
         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 @@ ENTRY(v7wbi_flush_kern_tlb_range)
         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 @@ ENDPROC(v7wbi_flush_kern_tlb_range)
 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