From fd37f195cacc068ad4c070dd794643fcb25ef21a Mon Sep 17 00:00:00 2001
From: Fabio Estevam <fabio.estevam@freescale.com>
Date: Tue, 17 Sep 2013 23:13:10 -0300
Subject: [PATCH] net: fec_mxc: Fix timeouts during tftp transfer
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Performing tftp transfers on mx28 results in random timeouts.

Hector Palacios and Robert Hodaszi analyzed the root cause being related to the
wrong alignment of the 'buff' buffer inside fec_recv().

Benoît Thébaudeau provided an excellent analysis of the alignment bug that is
present on older versions, such as GCC 4.5.4:

http://marc.info/?l=u-boot&m=137942904906131&w=2

Use ALLOC_CACHE_ALIGN_BUFFER() to avoid alignment issues from older GCC
versions.

Reported-by: Hector Palacios <hector.palacios@digi.com>
Tested-by: Oliver Metz <oliver@freetz.org>
Tested-by: Hector Palacios <hector.palacios@digi.com>
Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Marek Vasut <marex@denx.de>
Tested-by: Marek Vasut <marex@denx.de>
---
 drivers/net/fec_mxc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/fec_mxc.c b/drivers/net/fec_mxc.c
index 210ef02df53..107cd6ecc5c 100644
--- a/drivers/net/fec_mxc.c
+++ b/drivers/net/fec_mxc.c
@@ -794,7 +794,7 @@ static int fec_recv(struct eth_device *dev)
 	uint16_t bd_status;
 	uint32_t addr, size, end;
 	int i;
-	uchar buff[FEC_MAX_PKT_SIZE] __aligned(ARCH_DMA_MINALIGN);
+	ALLOC_CACHE_ALIGN_BUFFER(uchar, buff, FEC_MAX_PKT_SIZE);
 
 	/*
 	 * Check if any critical events have happened
-- 
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