On 2020/05/13 Sascha Hauer <s.hauer@xxxxxxxxxxxxxx> wrote: > On Wed, May 13, 2020 at 09:05:33AM +0000, Robin Gong wrote: > > On 2020/05/13 Sascha Hauer <s.hauer@xxxxxxxxxxxxxx> wrote:d > > > > drivers/spi/spi-imx.c | 16 ++++++++-------- > > > > 1 file changed, 8 insertions(+), 8 deletions(-) > > > > > > > > diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c index > > > > f4f28a4..70df8e6 100644 > > > > --- a/drivers/spi/spi-imx.c > > > > +++ b/drivers/spi/spi-imx.c > > > > @@ -585,8 +585,8 @@ static int mx51_ecspi_prepare_transfer(struct > > > spi_imx_data *spi_imx, > > > > ctrl |= mx51_ecspi_clkdiv(spi_imx, t->speed_hz, &clk); > > > > spi_imx->spi_bus_clk = clk; > > > > > > > > - if (spi_imx->usedma) > > > > - ctrl |= MX51_ECSPI_CTRL_SMC; > > > > + /* ERR009165: work in XHC mode as PIO */ > > > > + ctrl &= ~MX51_ECSPI_CTRL_SMC; > > > > > > > > writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL); > > > > > > > > @@ -617,7 +617,7 @@ static void mx51_setup_wml(struct spi_imx_data > > > *spi_imx) > > > > * and enable DMA request. > > > > */ > > > > writel(MX51_ECSPI_DMA_RX_WML(spi_imx->wml - 1) | > > > > - MX51_ECSPI_DMA_TX_WML(spi_imx->wml) | > > > > + MX51_ECSPI_DMA_TX_WML(0) | > > > > MX51_ECSPI_DMA_RXT_WML(spi_imx->wml) | > > > > MX51_ECSPI_DMA_TEDEN | MX51_ECSPI_DMA_RXDEN | > > > > MX51_ECSPI_DMA_RXTDEN, spi_imx->base + > MX51_ECSPI_DMA); > > > @@ -1171,7 > > > > +1171,11 @@ static int spi_imx_dma_configure(struct spi_master > > > > +*master) > > > > tx.direction = DMA_MEM_TO_DEV; > > > > tx.dst_addr = spi_imx->base_phys + MXC_CSPITXDATA; > > > > tx.dst_addr_width = buswidth; > > > > - tx.dst_maxburst = spi_imx->wml; > > > > + /* > > > > + * For ERR009165 with tx_wml = 0 could enlarge burst size to fifo size > > > > + * to speed up fifo filling as possible. > > > > + */ > > > > + tx.dst_maxburst = spi_imx->devtype_data->fifo_size; > > > > > > In the next patch this is changed again to: > > > > > > + if (spi_imx->devtype_data->tx_glitch_fixed) > > > + tx.dst_maxburst = spi_imx->wml; > > > + else > > > + tx.dst_maxburst = spi_imx->devtype_data->fifo_size; > > > > > > So with tx_glitch_fixed we end up with tx.dst_maxburst being the > > > same as two patches before which is rather confusing. Better > > > introduce tx_glitch_fixed in this patch, or maybe even merge this patch and > the next one. > > Sorry confused you, I should repleace 'tx_wml=0' in the above comments > > with ' TX_THRESHOLD=0', which means tx transfer dma have to wait all > > the tx data in tx fifo transferred with ERR009165 rather than > > generically 'tx_wml' (for example --half fifo size used as > > TX_THRESHOLD). Obviously TX_THRESHOLD=0 would down performance, so > > enlarge dst_maxburst to fifo size as PIO with ERR009165. After > > ERR009165 fixed at HW level. TX_THRESHOLD could be used as common > > 'spi_imx->wml' so change it back. Will add more detail information in > > v8. > > I am not confused, I meant the patches are confusing. What you are doing > is: > > No patch: > tx.dst_maxburst = a; > > 1st patch > tx.dst_maxburst = b; > > 2nd patch: > > if (foo) > tx.dst_maxburst = a; > else > tx.dst_maxburst = b; > > It would be better readable and understandable if you did that in one patch, > because that would directly say "Under certain conditions we have to choose a, > otherwise b". That's much better than changing "a" to "b" and then to "a or b" > Okay, I'll merge those 2 changes into the next 08/13.
