powerpc: purge all the prefetched instructions for the coherent icache flush
As Benjamin Herrenschmidt has indicated, we still need a dummy icbi to
purge all the prefetched instructions from the ifetch buffers for the
snooping icache. We also need a sync before the icbi to order the
actual stores to memory that might have modified instructions with
the icbi.
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/include/asm/cache.h b/arch/powerpc/include/asm/cache.h
index 9e495c9..ed0afc1 100644
--- a/arch/powerpc/include/asm/cache.h
+++ b/arch/powerpc/include/asm/cache.h
@@ -41,8 +41,20 @@
extern struct ppc64_caches ppc64_caches;
#endif /* __powerpc64__ && ! __ASSEMBLY__ */
-#if !defined(__ASSEMBLY__)
+#if defined(__ASSEMBLY__)
+/*
+ * For a snooping icache, we still need a dummy icbi to purge all the
+ * prefetched instructions from the ifetch buffers. We also need a sync
+ * before the icbi to order the the actual stores to memory that might
+ * have modified instructions with the icbi.
+ */
+#define PURGE_PREFETCHED_INS \
+ sync; \
+ icbi 0,r3; \
+ sync; \
+ isync
+#else
#define __read_mostly __attribute__((__section__(".data..read_mostly")))
#ifdef CONFIG_6xx
diff --git a/arch/powerpc/kernel/misc_32.S b/arch/powerpc/kernel/misc_32.S
index e47d268..879f096 100644
--- a/arch/powerpc/kernel/misc_32.S
+++ b/arch/powerpc/kernel/misc_32.S
@@ -344,7 +344,7 @@
*/
_KPROBE(flush_icache_range)
BEGIN_FTR_SECTION
- isync
+ PURGE_PREFETCHED_INS
blr /* for 601, do nothing */
END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
li r5,L1_CACHE_BYTES-1
@@ -448,6 +448,7 @@
*/
_GLOBAL(__flush_dcache_icache)
BEGIN_FTR_SECTION
+ PURGE_PREFETCHED_INS
blr
END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
rlwinm r3,r3,0,0,31-PAGE_SHIFT /* Get page base address */
@@ -489,6 +490,7 @@
*/
_GLOBAL(__flush_dcache_icache_phys)
BEGIN_FTR_SECTION
+ PURGE_PREFETCHED_INS
blr /* for 601, do nothing */
END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
mfmsr r10
diff --git a/arch/powerpc/kernel/misc_64.S b/arch/powerpc/kernel/misc_64.S
index e59caf8..a9f7a79 100644
--- a/arch/powerpc/kernel/misc_64.S
+++ b/arch/powerpc/kernel/misc_64.S
@@ -67,6 +67,7 @@
_KPROBE(flush_icache_range)
BEGIN_FTR_SECTION
+ PURGE_PREFETCHED_INS
blr
END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
/*
@@ -211,6 +212,11 @@
* Different systems have different cache line sizes
*/
+BEGIN_FTR_SECTION
+ PURGE_PREFETCHED_INS
+ blr
+END_FTR_SECTION_IFSET(CPU_FTR_COHERENT_ICACHE)
+
/* Flush the dcache */
ld r7,PPC64_CACHES@toc(r2)
clrrdi r3,r3,PAGE_SHIFT /* Page align */