From 0ec9ebc706fbd394bc233d87ac7aaad1c4f3ab54 Mon Sep 17 00:00:00 2001 From: Thomas Petazzoni Date: Wed, 8 Jul 2015 16:28:14 +0200 Subject: [PATCH] dmaengine: mv_xor: fix big endian operation in register mode Commit 6f166312c6ea2 ("dmaengine: mv_xor: add support for a38x command in descriptor mode") introduced the support for a feature that appeared in Armada 38x: specifying the operation to be performed in a per-descriptor basis rather than globally per channel. However, when doing so, it changed the function mv_chan_set_mode() to use: if (IS_ENABLED(__BIG_ENDIAN)) instead of: #if defined(__BIG_ENDIAN) While IS_ENABLED() is perfectly fine for CONFIG_* symbols, it is not for other symbols such as __BIG_ENDIAN that is provided directly by the compiler. Consequently, the commit broke support for big-endian, as the XOR_DESCRIPTOR_SWAP flag was not set in the XOR channel configuration register. The primarily visible effect was some nasty warnings and failures appearing during the self-test of the XOR unit: [ 1.197368] mv_xor d0060900.xor: error on chan 0. intr cause 0x00000082 [ 1.197393] mv_xor d0060900.xor: config 0x00008440 [ 1.197410] mv_xor d0060900.xor: activation 0x00000000 [ 1.197427] mv_xor d0060900.xor: intr cause 0x00000082 [ 1.197443] mv_xor d0060900.xor: intr mask 0x000003f7 [ 1.197460] mv_xor d0060900.xor: error cause 0x00000000 [ 1.197477] mv_xor d0060900.xor: error addr 0x00000000 [ 1.197491] ------------[ cut here ]------------ [ 1.197513] WARNING: CPU: 0 PID: 1 at ../drivers/dma/mv_xor.c:664 mv_xor_interrupt_handler+0x14c/0x170() See also: http://storage.kernelci.org/next/next-20150617/arm-mvebu_v7_defconfig+CONFIG_CPU_BIG_ENDIAN=y/lab-khilman/boot-armada-xp-openblocks-ax3-4.txt Signed-off-by: Thomas Petazzoni Fixes: 6f166312c6ea2 ("dmaengine: mv_xor: add support for a38x command in descriptor mode") Reviewed-by: Maxime Ripard Signed-off-by: Vinod Koul --- drivers/dma/mv_xor.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/dma/mv_xor.c b/drivers/dma/mv_xor.c index fbaf1ead2597..f1325f62563e 100644 --- a/drivers/dma/mv_xor.c +++ b/drivers/dma/mv_xor.c @@ -162,10 +162,11 @@ static void mv_chan_set_mode(struct mv_xor_chan *chan, config &= ~0x7; config |= op_mode; - if (IS_ENABLED(__BIG_ENDIAN)) - config |= XOR_DESCRIPTOR_SWAP; - else - config &= ~XOR_DESCRIPTOR_SWAP; +#if defined(__BIG_ENDIAN) + config |= XOR_DESCRIPTOR_SWAP; +#else + config &= ~XOR_DESCRIPTOR_SWAP; +#endif writel_relaxed(config, XOR_CONFIG(chan)); chan->current_type = type; -- 2.34.1