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-rw-r--r--arch/sh/mm/uncached.c34
1 files changed, 34 insertions, 0 deletions
diff --git a/arch/sh/mm/uncached.c b/arch/sh/mm/uncached.c
new file mode 100644
index 000000000000..cf20a5c5136a
--- /dev/null
+++ b/arch/sh/mm/uncached.c
@@ -0,0 +1,34 @@
+#include <linux/init.h>
+#include <asm/sizes.h>
+#include <asm/page.h>
+
+/*
+ * This is the offset of the uncached section from its cached alias.
+ *
+ * Legacy platforms handle trivial transitions between cached and
+ * uncached segments by making use of the 1:1 mapping relationship in
+ * 512MB lowmem, others via a special uncached mapping.
+ *
+ * Default value only valid in 29 bit mode, in 32bit mode this will be
+ * updated by the early PMB initialization code.
+ */
+unsigned long cached_to_uncached = SZ_512M;
+unsigned long uncached_size = SZ_512M;
+unsigned long uncached_start, uncached_end;
+
+int virt_addr_uncached(unsigned long kaddr)
+{
+ return (kaddr >= uncached_start) && (kaddr < uncached_end);
+}
+
+void __init uncached_init(void)
+{
+ uncached_start = memory_end;
+ uncached_end = uncached_start + uncached_size;
+}
+
+void __init uncached_resize(unsigned long size)
+{
+ uncached_size = size;
+ uncached_end = uncached_start + uncached_size;
+}