[PATCH 3/5] powerpc: Remove arch specific byteswappers from the MXC MMC driver

David Gibson
2015-02-03T05:36:10Z

When the MXC MMUC driver is used on a Freescale MPC512x machine, it
contains some additional byteswapping code (I'm assuming this is a
workaround for a hardware defect). This uses the ppc specific st_le32()
function, but there's no reason not to use the generic swab32() function
instead. gcc is capable of generating the efficient ppc byte-reversing
load/store instructions without the arch-specific helper.

This patch, therefore, switches to the generic byteswap routine.

Cc: Shawn Guo <shawn.guo@linaro.org>
Cc: Sascha Hauer <kernel@pengutronix.de>

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
---
drivers/mmc/host/mxcmmc.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mmc/host/mxcmmc.c b/drivers/mmc/host/mxcmmc.c
index 5316d9b..317d709 100644
--- a/drivers/mmc/host/mxcmmc.c
+++ b/drivers/mmc/host/mxcmmc.c
@@ -281,7 +281,7 @@ static inline void buffer_swap32(u32 *buf, int len)
int i;

for (i = 0; i < ((len + 3) / 4); i++) {
- st_le32(buf, *buf);
+ *buf = swab32(*buf);
buf++;
}
}
--
2.1.0