RE: [RESEND v6 06/13] spi: imx: fix ERR009165
From: Robin Gong <hidden>
Date: 2020-03-10 08:27:48
Also in:
dmaengine, linux-devicetree, linux-spi, lkml
On 2020/03/10 Sascha Hauer [off-list ref] wrote:
On Tue, Mar 10, 2020 at 07:31:55PM +0800, Robin Gong wrote:quoted
Change to XCH mode even in dma mode, please refer to the below errata: https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.nxp.com%2Fdocs%2Fen%2Ferrata%2FIMX6DQCE.pdf&data=02%7C01%7C yibin.gquoted
ong%40nxp.com%7Ccbabce268dfd4b0a0e2a08d7c4c62ff6%7C686ea1d3bc2b4c 6fa92quoted
cd99c5c301635%7C0%7C1%7C637194227793913712&sdata=Q5N49T4jgX TcdTzsBquoted
3D0saK2%2Fzj0R4gnJcGR%2Bd70Fm4%3D&reserved=0 Signed-off-by: Robin Gong <redacted> Acked-by: Mark Brown <broonie@kernel.org> --- drivers/spi/spi-imx.c | 17 ++++++++++------- 1 file changed, 10 insertions(+), 7 deletions(-)diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c indexf4f28a4..842a86e 100644--- a/drivers/spi/spi-imx.c +++ b/drivers/spi/spi-imx.c@@ -585,8 +585,9 @@ static int mx51_ecspi_prepare_transfer(structspi_imx_data *spi_imx,quoted
ctrl |= mx51_ecspi_clkdiv(spi_imx, t->speed_hz, &clk); spi_imx->spi_bus_clk = clk; + /* ERR009165: work in XHC mode as PIO */ if (spi_imx->usedma) - ctrl |= MX51_ECSPI_CTRL_SMC; + ctrl &= ~MX51_ECSPI_CTRL_SMC;'ctrl' was read from the hardware. In the dma case it was set explicitly, but it was never cleared for a PIO transfer. This looked wrong before this patch. Now with this patch it looks even more wrong: We clear a bit that has never been set and we only do this for DMA, when for the PIO case it definitly must be cleared. Drop the if clause.
Good point, ACK.
quoted
writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);@@ -612,12 +613,14 @@ static int mx51_ecspi_prepare_transfer(structspi_imx_data *spi_imx, static void mx51_setup_wml(struct spi_imx_data *spi_imx) { + u32 tx_wml = 0; + /* * Configure the DMA register: setup the watermark * 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(tx_wml) |tx_wml is never assigned any other value than 0. Drop the variable.
That's prepared for 07/13 patch which may assign spi_imx->wml to tx_wml.
quoted hunk ↗ jump to hunk
quoted
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);@@ -1171,7quoted
+1174,11 @@ 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; ret = dmaengine_slave_config(master->dma_tx, &tx); if (ret) { dev_err(spi_imx->dev, "TX dma configuration failed with %d\n", ret); @@ -1265,10 +1272,6 @@ static int spi_imx_sdma_init(struct device *dev, struct spi_imx_data *spi_imx, { int ret; - /* use pio mode for i.mx6dl chip TKT238285 */ - if (of_machine_is_compatible("fsl,imx6dl")) - return 0;So with this patch it becomes possible to do DMA on i.MX6dl, but it is mentioned nowhere.
That's a common IP issue but caught on i.mx6dl at that time, so this time I didn't mention i.mx6dl.
Sascha -- Pengutronix e.K. | | Steuerwalder Str. 21 | https://eur01.safelinks.protection.outlook.com/?url=http%3A%2F%2Fwww.pe ngutronix.de%2F&data=02%7C01%7Cyibin.gong%40nxp.com%7Ccbabce2 68dfd4b0a0e2a08d7c4c62ff6%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0% 7C1%7C637194227793913712&sdata=TL%2BheiNsYVPld3qyzWjF6yQZgH2 HLdVFxzFeK3MupTc%3D&reserved=0 | 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 | Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
_______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel