powerpc/mm: Add SMP support to no-hash TLB handling

This commit moves the whole no-hash TLB handling out of line into a
new tlb_nohash.c file, and implements some basic SMP support using
IPIs and/or broadcast tlbivax instructions.

Note that I'm using local invalidations for D->I cache coherency.

At worst, if another processor is trying to execute the same and
has the old entry in its TLB, it will just take a fault and re-do
the TLB flush locally (it won't re-do the cache flush in any case).

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: Kumar Gala <galak@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 9 insertions, 0 deletions

diff --git a/arch/powerpc/kernel/misc_32.S b/arch/powerpc/kernel/misc_32.S
index 5c33bc14bd9f..2c2ab89f0b64 100644
--- a/arch/powerpc/kernel/misc_32.S
+++ b/arch/powerpc/kernel/misc_32.S
@@ -29,6 +29,7 @@
 #include <asm/asm-offsets.h>
 #include <asm/processor.h>
 #include <asm/kexec.h>
+#include <asm/bug.h>
 
         .text
 
@@ -496,6 +497,14 @@ _GLOBAL(_tlbil_va)
         blr
 #endif /* CONFIG_FSL_BOOKE */
 
+/*
+ * Nobody implements this yet
+ */
+_GLOBAL(_tlbivax_bcast)
+1:      trap
+        EMIT_BUG_ENTRY 1b,__FILE__,__LINE__,0;
+        blr
+
 
 /*
  * Flush instruction cache.