[PATCH] MIPS: Disable address swizzling on __raw MMIO operations (resend)

From: Kevin Cernekee
Date: Sun Jun 14 2009 - 12:26:55 EST


{read,write}[bwlq] are used for PCI and may therefore need to implement
address or data swizzling on big-endian systems. Those operations are
unaffected by this patch.

__raw_{read,write}[bwlq] should always implement unswizzled accesses.
Currently on MIPS, the __raw operations do not swizzle data (good) but
do swizzle addresses (bad). This causes problems with code that
assumes the __raw operations use the system's native endianness, such
as the MTD physmap/CFI drivers.

It also means that the __raw behavior is not consistent between
BE systems that use address swizzling (IP32) and BE systems that
use CONFIG_SWAP_IO_SPACE for data swizzling (IP22).

Signed-off-by: Kevin Cernekee <cernekee@xxxxxxxxx>
---
arch/mips/include/asm/io.h | 22 +++++++++++++---------
1 files changed, 13 insertions(+), 9 deletions(-)

diff --git a/arch/mips/include/asm/io.h b/arch/mips/include/asm/io.h
index 436878e..ea0647c 100644
--- a/arch/mips/include/asm/io.h
+++ b/arch/mips/include/asm/io.h
@@ -301,7 +301,7 @@ static inline void iounmap(const volatile void __iomem *addr)
#define war_octeon_io_reorder_wmb() do { } while (0)
#endif

-#define __BUILD_MEMORY_SINGLE(pfx, bwlq, type, irq) \
+#define __BUILD_MEMORY_SINGLE(pfx, bwlq, type, irq, swiz) \
\
static inline void pfx##write##bwlq(type val, \
volatile void __iomem *mem) \
@@ -311,7 +311,9 @@ static inline void pfx##write##bwlq(type val, \
\
war_octeon_io_reorder_wmb(); \
\
- __mem = (void *)__swizzle_addr_##bwlq((unsigned long)(mem)); \
+ __mem = swiz ? \
+ (void *)__swizzle_addr_##bwlq((unsigned long)(mem)) : \
+ (void *)mem; \
\
__val = pfx##ioswab##bwlq(__mem, val); \
\
@@ -344,7 +346,9 @@ static inline type pfx##read##bwlq(const volatile void __iomem *mem) \
volatile type *__mem; \
type __val; \
\
- __mem = (void *)__swizzle_addr_##bwlq((unsigned long)(mem)); \
+ __mem = swiz ? \
+ (void *)__swizzle_addr_##bwlq((unsigned long)(mem)) : \
+ (void *)mem; \
\
if (sizeof(type) != sizeof(u64) || sizeof(u64) == sizeof(long)) \
__val = *__mem; \
@@ -406,15 +410,15 @@ static inline type pfx##in##bwlq##p(unsigned long port) \
return pfx##ioswab##bwlq(__addr, __val); \
}

-#define __BUILD_MEMORY_PFX(bus, bwlq, type) \
+#define __BUILD_MEMORY_PFX(bus, bwlq, type, swiz) \
\
-__BUILD_MEMORY_SINGLE(bus, bwlq, type, 1)
+__BUILD_MEMORY_SINGLE(bus, bwlq, type, 1, swiz)

#define BUILDIO_MEM(bwlq, type) \
\
-__BUILD_MEMORY_PFX(__raw_, bwlq, type) \
-__BUILD_MEMORY_PFX(, bwlq, type) \
-__BUILD_MEMORY_PFX(__mem_, bwlq, type) \
+__BUILD_MEMORY_PFX(__raw_, bwlq, type, 0) \
+__BUILD_MEMORY_PFX(, bwlq, type, 1) \
+__BUILD_MEMORY_PFX(__mem_, bwlq, type, 1) \

BUILDIO_MEM(b, u8)
BUILDIO_MEM(w, u16)
@@ -438,7 +442,7 @@ BUILDIO_IOPORT(q, u64)

#define __BUILDIO(bwlq, type) \
\
-__BUILD_MEMORY_SINGLE(____raw_, bwlq, type, 0)
+__BUILD_MEMORY_SINGLE(____raw_, bwlq, type, 0, 0)

__BUILDIO(q, u64)

--
1.5.3.6

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