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: 64e36824b3 ("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>
This commit is contained in:
Addy Ke 2016-01-22 19:06:52 +08:00 committed by Vinod Koul
parent 86a8ce7d41
commit 80abf8880c
1 changed files with 10 additions and 2 deletions

View File

@ -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;