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--- a/arch/arm/include/asm/glue-cache.h
+++ b/arch/arm/include/asm/glue-cache.h
@@ -156,9 +156,15 @@ static inline void nop_dma_unmap_area(co
#define __cpuc_flush_user_range __glue(_CACHE,_flush_user_cache_range)
#define __cpuc_coherent_kern_range __glue(_CACHE,_coherent_kern_range)
#define __cpuc_coherent_user_range __glue(_CACHE,_coherent_user_range)
-#define __cpuc_flush_dcache_area __glue(_CACHE,_flush_kern_dcache_area)
-#define dmac_flush_range __glue(_CACHE,_dma_flush_range)
+#ifndef CONFIG_DMA_CACHE_FIQ_BROADCAST
+# define __cpuc_flush_dcache_area __glue(_CACHE,_flush_kern_dcache_area)
+# define dmac_flush_range __glue(_CACHE,_dma_flush_range)
+#else
+# define __cpuc_flush_dcache_area __glue(fiq,_flush_kern_dcache_area)
+# define dmac_flush_range __glue(fiq,_dma_flush_range)
+#endif
+
#endif
#endif
--- a/arch/arm/mm/Kconfig
+++ b/arch/arm/mm/Kconfig
@@ -866,6 +866,17 @@ config DMA_CACHE_RWFO
in hardware, other workarounds are needed (e.g. cache
maintenance broadcasting in software via FIQ).
+config DMA_CACHE_FIQ_BROADCAST
+ bool "Enable fiq broadcast DMA cache maintenance"
+ depends on CPU_V6K && SMP
+ select FIQ
+ help
+ The Snoop Control Unit on ARM11MPCore does not detect the
+ cache maintenance operations and the dma_{map,unmap}_area()
+ functions may leave stale cache entries on other CPUs. By
+ enabling this option, fiq broadcast in the ARMv6
+ DMA cache maintenance functions is performed.
+
config OUTER_CACHE
bool
--- a/arch/arm/mm/flush.c
+++ b/arch/arm/mm/flush.c
@@ -319,6 +319,7 @@ void __sync_icache_dcache(pte_t pteval)
void flush_dcache_page(struct page *page)
{
struct address_space *mapping;
+ bool skip_broadcast = true;
/*
* The zero page is never written to, so never has any dirty
@@ -329,7 +330,10 @@ void flush_dcache_page(struct page *page
mapping = page_mapping(page);
- if (!cache_ops_need_broadcast() &&
+#ifndef CONFIG_DMA_CACHE_FIQ_BROADCAST
+ skip_broadcast = !cache_ops_need_broadcast();
+#endif
+ if (skip_broadcast &&
mapping && !page_mapped(page))
clear_bit(PG_dcache_clean, &page->flags);
else {
--- a/arch/arm/mm/dma.h
+++ b/arch/arm/mm/dma.h
@@ -4,8 +4,13 @@
#include <asm/glue-cache.h>
#ifndef MULTI_CACHE
-#define dmac_map_area __glue(_CACHE,_dma_map_area)
-#define dmac_unmap_area __glue(_CACHE,_dma_unmap_area)
+#ifndef CONFIG_DMA_CACHE_FIQ_BROADCAST
+# define dmac_map_area __glue(_CACHE,_dma_map_area)
+# define dmac_unmap_area __glue(_CACHE,_dma_unmap_area)
+#else
+# define dmac_map_area __glue(fiq,_dma_map_area)
+# define dmac_unmap_area __glue(fiq,_dma_unmap_area)
+#endif
/*
* These are private to the dma-mapping API. Do not use directly.
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