[MIPS] Make ioremap() work on TX39/49 special unmapped segment

TX39XX and TX49XX have "reserved" segment in CKSEG3 area.
0xff000000-0xff3fffff on TX49XX and 0xff000000-0xfffeffff on TX39XX
are reserved (unmapped, uncached).  Controllers on these SoCs are
placed in this segment.

This patch add plat_ioremap() and plat_iounmap() to override default
behavior and implement these hooks for TX39/TX49.

Signed-off-by: Atsushi Nemoto <anemo@mba.ocn.ne.jp>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 42 insertions, 0 deletions

diff --git a/include/asm-mips/mach-tx49xx/ioremap.h b/include/asm-mips/mach-tx49xx/ioremap.h
new file mode 100644
index 000000000000..88cf546719b8
--- /dev/null
+++ b/include/asm-mips/mach-tx49xx/ioremap.h
@@ -0,0 +1,42 @@
+/*
+ *      include/asm-mips/mach-tx49xx/ioremap.h
+ *
+ *      This program is free software; you can redistribute it and/or
+ *      modify it under the terms of the GNU General Public License
+ *      as published by the Free Software Foundation; either version
+ *      2 of the License, or (at your option) any later version.
+ */
+#ifndef __ASM_MACH_TX49XX_IOREMAP_H
+#define __ASM_MACH_TX49XX_IOREMAP_H
+
+#include <linux/types.h>
+
+/*
+ * Allow physical addresses to be fixed up to help peripherals located
+ * outside the low 32-bit range -- generic pass-through version.
+ */
+static inline phys_t fixup_bigphys_addr(phys_t phys_addr, phys_t size)
+{
+        return phys_addr;
+}
+
+static inline void __iomem *plat_ioremap(phys_t offset, unsigned long size,
+        unsigned long flags)
+{
+#ifdef CONFIG_64BIT
+#define TXX9_DIRECTMAP_BASE     0xfff000000ul
+#else
+#define TXX9_DIRECTMAP_BASE     0xff000000ul
+#endif
+        if (offset >= TXX9_DIRECTMAP_BASE &&
+            offset < TXX9_DIRECTMAP_BASE + 0x400000)
+                return (void __iomem *)(unsigned long)(int)offset;
+        return NULL;
+}
+
+static inline int plat_iounmap(const volatile void __iomem *addr)
+{
+        return (unsigned long)addr >= (unsigned long)(int)TXX9_DIRECTMAP_BASE;
+}
+
+#endif /* __ASM_MACH_TX49XX_IOREMAP_H */