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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-08-05 17:04:01 -0300
commit57f0f512b273f60d52568b8c6b77e17f5636edc0 (patch)
tree5e910f0e82173f4ef4f51111366a3f1299037a7b /arch/sh/mm/uncached.c
Initial import
Diffstat (limited to 'arch/sh/mm/uncached.c')
-rw-r--r--arch/sh/mm/uncached.c43
1 files changed, 43 insertions, 0 deletions
diff --git a/arch/sh/mm/uncached.c b/arch/sh/mm/uncached.c
new file mode 100644
index 000000000..a7767da81
--- /dev/null
+++ b/arch/sh/mm/uncached.c
@@ -0,0 +1,43 @@
+#include <linux/init.h>
+#include <linux/module.h>
+#include <asm/sizes.h>
+#include <asm/page.h>
+#include <asm/addrspace.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;
+EXPORT_SYMBOL(uncached_start);
+EXPORT_SYMBOL(uncached_end);
+
+int virt_addr_uncached(unsigned long kaddr)
+{
+ return (kaddr >= uncached_start) && (kaddr < uncached_end);
+}
+EXPORT_SYMBOL(virt_addr_uncached);
+
+void __init uncached_init(void)
+{
+#if defined(CONFIG_29BIT) || !defined(CONFIG_MMU)
+ uncached_start = P2SEG;
+#else
+ uncached_start = memory_end;
+#endif
+ uncached_end = uncached_start + uncached_size;
+}
+
+void __init uncached_resize(unsigned long size)
+{
+ uncached_size = size;
+ uncached_end = uncached_start + uncached_size;
+}