diff options
| author | Addy Ke <addy.ke@rock-chips.com> | 2016-01-22 19:06:52 +0800 |
|---|---|---|
| committer | Vinod Koul <vinod.koul@intel.com> | 2016-02-09 09:01:42 +0530 |
| commit | 80abf8880cc6e1594c11b7c417f22dde60e25312 (patch) | |
| tree | 60f88bf2b78f95530d3197854b3e2dd8f6ac8e06 /drivers/spi/spi-rockchip.c | |
| parent | 86a8ce7d4103f6680236af6916abf38e12477df8 (diff) | |
| download | linux-80abf8880cc6e1594c11b7c417f22dde60e25312.tar.gz linux-80abf8880cc6e1594c11b7c417f22dde60e25312.tar.bz2 linux-80abf8880cc6e1594c11b7c417f22dde60e25312.zip | |
spi: rockchip: modify DMA max burst to 1
Generic dma controller on Rockchips' platform cannot support
DMAFLUSHP instruction which make dma to flush the req of non-aligned
or non-multiple of what we need. That will cause an unrecoverable
dma bus error. The saftest way is to set dma max burst to 1.
Signed-off-by: Addy ke <addy.ke@rock-chips.com>
Fixes: 64e36824b32b06 ("spi/rockchip: add driver for Rockchip...")
Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com>
cc: Heiko Stuebner <heiko@sntech.de>
cc: Olof Johansson <olof@lixom.net>
cc: Doug Anderson <dianders@chromium.org>
cc: Sonny Rao <sonnyrao@chromium.org>
Acked-by: Mark Brown <broonie@kernel.org>
Signed-off-by: Caesar Wang <wxt@rock-chips.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Diffstat (limited to 'drivers/spi/spi-rockchip.c')
| -rw-r--r-- | drivers/spi/spi-rockchip.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/drivers/spi/spi-rockchip.c b/drivers/spi/spi-rockchip.c index 79a8bc4f6cec..aa9561f586ab 100644 --- a/drivers/spi/spi-rockchip.c +++ b/drivers/spi/spi-rockchip.c @@ -199,6 +199,7 @@ struct rockchip_spi { struct sg_table rx_sg; struct rockchip_spi_dma_data dma_rx; struct rockchip_spi_dma_data dma_tx; + struct dma_slave_caps dma_caps; }; static inline void spi_enable_chip(struct rockchip_spi *rs, int enable) @@ -449,7 +450,10 @@ static void rockchip_spi_prepare_dma(struct rockchip_spi *rs) rxconf.direction = rs->dma_rx.direction; rxconf.src_addr = rs->dma_rx.addr; rxconf.src_addr_width = rs->n_bytes; - rxconf.src_maxburst = rs->n_bytes; + if (rs->dma_caps.max_burst > 4) + rxconf.src_maxburst = 4; + else + rxconf.src_maxburst = 1; dmaengine_slave_config(rs->dma_rx.ch, &rxconf); rxdesc = dmaengine_prep_slave_sg( @@ -466,7 +470,10 @@ static void rockchip_spi_prepare_dma(struct rockchip_spi *rs) txconf.direction = rs->dma_tx.direction; txconf.dst_addr = rs->dma_tx.addr; txconf.dst_addr_width = rs->n_bytes; - txconf.dst_maxburst = rs->n_bytes; + if (rs->dma_caps.max_burst > 4) + txconf.dst_maxburst = 4; + else + txconf.dst_maxburst = 1; dmaengine_slave_config(rs->dma_tx.ch, &txconf); txdesc = dmaengine_prep_slave_sg( @@ -730,6 +737,7 @@ static int rockchip_spi_probe(struct platform_device *pdev) } if (rs->dma_tx.ch && rs->dma_rx.ch) { + dma_get_slave_caps(rs->dma_rx.ch, &(rs->dma_caps)); rs->dma_tx.addr = (dma_addr_t)(mem->start + ROCKCHIP_SPI_TXDR); rs->dma_rx.addr = (dma_addr_t)(mem->start + ROCKCHIP_SPI_RXDR); rs->dma_tx.direction = DMA_MEM_TO_DEV; |