[RFC 3/9] MIPS: add virt_to_phys() and phys_to_virt()
Antony Pavlov
antonynpavlov at gmail.com
Thu Aug 27 15:24:04 PDT 2015
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 at 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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