1 files changed, 29 insertions, 7 deletions

diff --git a/arch/sh/mm/cache.c b/arch/sh/mm/cache.c
index 35c37b7f717..b8607fa7ae1 100644
--- a/arch/sh/mm/cache.c
+++ b/arch/sh/mm/cache.c
@@ -27,8 +27,11 @@ void (*local_flush_icache_page)(void *args) = cache_noop;
 void (*local_flush_cache_sigtramp)(void *args) = cache_noop;
 
 void (*__flush_wback_region)(void *start, int size);
+EXPORT_SYMBOL(__flush_wback_region);
 void (*__flush_purge_region)(void *start, int size);
+EXPORT_SYMBOL(__flush_purge_region);
 void (*__flush_invalidate_region)(void *start, int size);
+EXPORT_SYMBOL(__flush_invalidate_region);
 
 static inline void noop__flush_region(void *start, int size)
 {
@@ -128,14 +131,10 @@ void __update_cache(struct vm_area_struct *vma,
 		return;
 
 	page = pfn_to_page(pfn);
-	if (pfn_valid(pfn) && page_mapping(page)) {
+	if (pfn_valid(pfn)) {
 		int dirty = test_and_clear_bit(PG_dcache_dirty, &page->flags);
-		if (dirty) {
-			unsigned long addr = (unsigned long)page_address(page);
-
-			if (pages_do_alias(addr, address & PAGE_MASK))
-				__flush_purge_region((void *)addr, PAGE_SIZE);
-		}
+		if (dirty)
+			__flush_purge_region(page_address(page), PAGE_SIZE);
 	}
 }
 
@@ -161,14 +160,21 @@ void flush_cache_all(void)
 {
 	cacheop_on_each_cpu(local_flush_cache_all, NULL, 1);
 }
+EXPORT_SYMBOL(flush_cache_all);
 
 void flush_cache_mm(struct mm_struct *mm)
 {
+	if (boot_cpu_data.dcache.n_aliases == 0)
+		return;
+
 	cacheop_on_each_cpu(local_flush_cache_mm, mm, 1);
 }
 
 void flush_cache_dup_mm(struct mm_struct *mm)
 {
+	if (boot_cpu_data.dcache.n_aliases == 0)
+		return;
+
 	cacheop_on_each_cpu(local_flush_cache_dup_mm, mm, 1);
 }
 
@@ -195,11 +201,13 @@ void flush_cache_range(struct vm_area_struct *vma, unsigned long start,
 
 	cacheop_on_each_cpu(local_flush_cache_range, (void *)&data, 1);
 }
+EXPORT_SYMBOL(flush_cache_range);
 
 void flush_dcache_page(struct page *page)
 {
 	cacheop_on_each_cpu(local_flush_dcache_page, page, 1);
 }
+EXPORT_SYMBOL(flush_dcache_page);
 
 void flush_icache_range(unsigned long start, unsigned long end)
 {
@@ -265,6 +273,12 @@ static void __init emit_cache_params(void)
 
 void __init cpu_cache_init(void)
 {
+	unsigned int cache_disabled = 0;
+
+#ifdef CCR
+	cache_disabled = !(__raw_readl(CCR) & CCR_CACHE_ENABLE);
+#endif
+
 	compute_alias(&boot_cpu_data.icache);
 	compute_alias(&boot_cpu_data.dcache);
 	compute_alias(&boot_cpu_data.scache);
@@ -273,6 +287,13 @@ void __init cpu_cache_init(void)
 	__flush_purge_region		= noop__flush_region;
 	__flush_invalidate_region	= noop__flush_region;
 
+	/*
+	 * No flushing is necessary in the disabled cache case so we can
+	 * just keep the noop functions in local_flush_..() and __flush_..()
+	 */
+	if (unlikely(cache_disabled))
+		goto skip;
+
 	if (boot_cpu_data.family == CPU_FAMILY_SH2) {
 		extern void __weak sh2_cache_init(void);
 
@@ -312,5 +333,6 @@ void __init cpu_cache_init(void)
 		sh5_cache_init();
 	}
 
+skip:
 	emit_cache_params();
 }