[PATCH 07/27] asm-generic: add minimal cache description

Arnd Bergmann
2009-04-30T15:42:01Z

Many architectures have a 32 byte cache line and never
require flushing the cache, so they can use these
generic implementation.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Remis Lima Baima <remis.developer@googlemail.com>
---
include/asm-generic/cache.h | 12 ++++++++++++
include/asm-generic/cacheflush.h | 30 ++++++++++++++++++++++++++++++
2 files changed, 42 insertions(+), 0 deletions(-)
create mode 100644 include/asm-generic/cache.h
create mode 100644 include/asm-generic/cacheflush.h

diff --git a/include/asm-generic/cache.h b/include/asm-generic/cache.h
new file mode 100644
index 0000000..1bfcfe5
--- /dev/null
+++ b/include/asm-generic/cache.h
@@ -0,0 +1,12 @@
+#ifndef __ASM_GENERIC_CACHE_H
+#define __ASM_GENERIC_CACHE_H
+/*
+ * 32 bytes appears to be the most common cache line size,
+ * so make that the default here. Architectures with larger
+ * cache lines need to provide their own cache.h.
+ */
+
+#define L1_CACHE_SHIFT 5
+#define L1_CACHE_BYTES (1 << L1_CACHE_SHIFT)
+
+#endif /* __ASM_GENERIC_CACHE_H */
diff --git a/include/asm-generic/cacheflush.h b/include/asm-generic/cacheflush.h
new file mode 100644
index 0000000..ba4ec39
--- /dev/null
+++ b/include/asm-generic/cacheflush.h
@@ -0,0 +1,30 @@
+#ifndef __ASM_CACHEFLUSH_H
+#define __ASM_CACHEFLUSH_H
+
+/* Keep includes the same across arches. */
+#include <linux/mm.h>
+
+/*
+ * The cache doesn't need to be flushed when TLB entries change when
+ * the cache is mapped to physical memory, not virtual memory
+ */
+#define flush_cache_all() do { } while (0)
+#define flush_cache_mm(mm) do { } while (0)
+#define flush_cache_dup_mm(mm) do { } while (0)
+#define flush_cache_range(vma, start, end) do { } while (0)
+#define flush_cache_page(vma, vmaddr, pfn) do { } while (0)
+#define flush_dcache_page(page) do { } while (0)
+#define flush_dcache_mmap_lock(mapping) do { } while (0)
+#define flush_dcache_mmap_unlock(mapping) do { } while (0)
+#define flush_icache_range(start, end) do { } while (0)
+#define flush_icache_page(vma,pg) do { } while (0)
+#define flush_icache_user_range(vma,pg,adr,len) do { } while (0)
+#define flush_cache_vmap(start, end) do { } while (0)
+#define flush_cache_vunmap(start, end) do { } while (0)
+
+#define copy_to_user_page(vma, page, vaddr, dst, src, len) \
+ memcpy(dst, src, len)
+#define copy_from_user_page(vma, page, vaddr, dst, src, len) \
+ memcpy(dst, src, len)
+
+#endif /* __ASM_CACHEFLUSH_H */
--
1.5.6.3