[RFC 3/9] MIPS: add virt_to_phys() and phys_to_virt()

[Antony Pavlov <antonynpavlov@gmail.com>]

N.B. phys_to_virt() translates phys address
to KSEG1 (uncached) address as barebox mips
has no cache support.

Signed-off-by: Antony Pavlov <antonynpavlov@gmail.com>
---
 arch/mips/include/asm/io.h | 35 +++++++++++++++++++++++++++++++++++
 1 file changed, 35 insertions(+)

diff --git a/arch/mips/include/asm/io.h b/arch/mips/include/asm/io.h
index 4832be6..26605a7 100644
--- a/arch/mips/include/asm/io.h
+++ b/arch/mips/include/asm/io.h
@@ -12,8 +12,43 @@
 
 #include <linux/compiler.h>
 #include <asm/types.h>
+#include <asm/addrspace.h>
 #include <asm/byteorder.h>
 
+/*
+ *     virt_to_phys    -       map virtual addresses to physical
+ *     @address: address to remap
+ *
+ *     The returned physical address is the physical (CPU) mapping for
+ *     the memory address given. It is only valid to use this function on
+ *     addresses directly mapped or allocated via kmalloc.
+ *
+ *     This function does not give bus mappings for DMA transfers. In
+ *     almost all conceivable cases a device driver should not be using
+ *     this function
+ */
+static inline unsigned long virt_to_phys(const void *address)
+{
+	return (unsigned long)address & 0x3fffffff;
+}
+
+/*
+ *     phys_to_virt    -       map physical address to virtual
+ *     @address: address to remap
+ *
+ *     The returned virtual address is a current CPU mapping for
+ *     the memory address given. It is only valid to use this function on
+ *     addresses that have a kernel mapping
+ *
+ *     This function does not handle bus mappings for DMA transfers. In
+ *     almost all conceivable cases a device driver should not be using
+ *     this function
+ */
+static inline void *phys_to_virt(unsigned long address)
+{
+	return (void *)(KSEG1 | (address & 0x3fffffff));
+}
+
 #define	IO_SPACE_LIMIT	0
 
 /*****************************************************************************/
-- 
2.5.0


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