This is a note to let you know that I've just added the patch titled
mtd: pxa3xx_nand: make the driver work on big-endian systems
to the 3.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
mtd-pxa3xx_nand-make-the-driver-work-on-big-endian-systems.patch
and it can be found in the queue-3.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From b7e460624f0f3c31150f3b09e75b0d009e22ba5f Mon Sep 17 00:00:00 2001
From: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx>
Date: Thu, 22 May 2014 14:56:52 +0200
Subject: mtd: pxa3xx_nand: make the driver work on big-endian systems
From: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx>
commit b7e460624f0f3c31150f3b09e75b0d009e22ba5f upstream.
The pxa3xx_nand driver currently uses __raw_writel() and __raw_readl()
to access I/O registers. However, those functions do not do any
endianness swapping, which means that they won't work when the CPU
runs in big-endian but the I/O registers are little endian, which is
the common situation for ARM systems running big endian.
Since __raw_writel() and __raw_readl() do not include any memory
barriers and the pxa3xx_nand driver can only be compiled for ARM
platforms, the closest I/o accessors functions that do endianess
swapping are writel_relaxed() and readl_relaxed().
This patch has been verified to work on Armada XP GP: without the
patch, the NAND is not detected when the kernel runs big endian while
it is properly detected when the kernel runs little endian. With the
patch applied, the NAND is properly detected in both situations
(little and big endian).
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Brian Norris <computersforpeace@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/mtd/nand/pxa3xx_nand.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/drivers/mtd/nand/pxa3xx_nand.c
+++ b/drivers/mtd/nand/pxa3xx_nand.c
@@ -93,10 +93,10 @@
/* macros for registers read/write */
#define nand_writel(info, off, val) \
- __raw_writel((val), (info)->mmio_base + (off))
+ writel_relaxed((val), (info)->mmio_base + (off))
#define nand_readl(info, off) \
- __raw_readl((info)->mmio_base + (off))
+ readl_relaxed((info)->mmio_base + (off))
/* error code and state */
enum {
Patches currently in stable-queue which might be from thomas.petazzoni@xxxxxxxxxxxxxxxxxx are
queue-3.4/mtd-pxa3xx_nand-make-the-driver-work-on-big-endian-systems.patch
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html