nslu2-kernel: split out LE part of drivers/mtd/maps/ixp4xx.c patch in 2.6.14

1 files changed, 54 insertions, 0 deletions

diff --git a/packages/linux/nslu2-kernel/2.6.14/10-ixp4xx-le.patch b/packages/linux/nslu2-kernel/2.6.14/10-ixp4xx-le.patch
new file mode 100644
index 0000000000..0b50e4e1a0
--- /dev/null
+++ b/packages/linux/nslu2-kernel/2.6.14/10-ixp4xx-le.patch
@@ -0,0 +1,54 @@
+--- linux-2.6.14/drivers/mtd/maps/ixp4xx.c	2005-10-27 17:02:08.000000000 -0700
++++ linux-2.6.14/drivers/mtd/maps/ixp4xx.c	2005-10-29 23:11:24.990820968 -0700
+@@ -22,6 +22,7 @@
+ #include <linux/string.h>
+ #include <linux/mtd/mtd.h>
+ #include <linux/mtd/map.h>
++#include <linux/mtd/cfi_endian.h>
+ #include <linux/mtd/partitions.h>
+ #include <linux/ioport.h>
+ #include <linux/device.h>
+@@ -30,17 +31,40 @@
+ 
+ #include <linux/reboot.h>
+ 
++/* On a little-endian IXP4XX system (tested on NSLU2) an LDRH or STRH
++ * will flip the second address bit - i.e. XOR the address with 10b.
++ * This causes the cfi commands (sent to the command address, 0xAA for
++ * 16 bit flash) to fail.  This is fixed here by XOR'ing the address
++ * before use with 10b.  The cost of this is that the flash layout ends
++ * up with pdp-endiannes (on an LE system), however this is not a problem
++ * as the access code consistently only accesses half words - so the
++ * endianness is not determinable on stuff which is written and read
++ * consistently in the little endian world.
++ *
++ * For flash data from the big-endian world, however, the results are
++ * weird - the pdp-endianness results in the data apparently being
++ * 2-byte swapped (as in dd conv=swab).  To work round this the 16
++ * bit values are written and read using cpu_to_cfi16 and cfi16_to_cpu,
++ * by default these are no-ops, but if the MTD driver is configed with
++ * CONFIG_MTD_CFI_BE_BYTE_SWAP the macros will byte swap the data,
++ * resulting in a consistently BE view of the flash on both BE (no
++ * op) and LE systems.  This config setting also causes the command
++ * data from the CFI implementation to get swapped - as is required
++ * so that this code will *unswap* it and give the correct command
++ * data to the flash.
++ */
+ #ifndef __ARMEB__
+ #define	BYTE0(h)	((h) & 0xFF)
+ #define	BYTE1(h)	(((h) >> 8) & 0xFF)
++#define	FLASHWORD(a)	(*(__u16*)((u32)(a) ^ 2))
+ #else
+ #define	BYTE0(h)	(((h) >> 8) & 0xFF)
+ #define	BYTE1(h)	((h) & 0xFF)
++#define	FLASHWORD(a)	(*(__u16*)(a))
+ #endif
+ 
+-#define FLASHWORD(a)	(*(__u16*)(a))
+-#define FLASHVAL(a)	FLASHWORD(a)
+-#define FLASHSET(a,v)	do { FLASHWORD(a) = (v); } while (0)
++#define FLASHVAL(a)	cfi16_to_cpu(FLASHWORD(a))
++#define FLASHSET(a,v)	(FLASHWORD(a) = cpu_to_cfi16(v))
+ 
+ static map_word ixp4xx_read16(struct map_info *map, unsigned long ofs)
+ {