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

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



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@xxxxxxxx>
Signed-off-by: Remis Lima Baima <remis.developer@xxxxxxxxxxxxxx>
---
 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


--
To unsubscribe from this list: send the line "unsubscribe linux-arch" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html

[Index of Archives]     [Linux Kernel]     [Kernel Newbies]     [x86 Platform Driver]     [Netdev]     [Linux Wireless]     [Netfilter]     [Bugtraq]     [Linux Filesystems]     [Yosemite Discussion]     [MIPS Linux]     [ARM Linux]     [Linux Security]     [Linux RAID]     [Samba]     [Device Mapper]

  Powered by Linux