From mboxrd@z Thu Jan 1 00:00:00 1970 From: Robin Gong Subject: RE: [RESEND v6 06/13] spi: imx: fix ERR009165 Date: Tue, 10 Mar 2020 08:27:41 +0000 Message-ID: References: <1583839922-22699-1-git-send-email-yibin.gong@nxp.com> <1583839922-22699-7-git-send-email-yibin.gong@nxp.com> <20200310073920.GR3335@pengutronix.de> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable Cc: "vkoul-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org" , "shawnguo-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org" , "u.kleine-koenig-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org" , "broonie-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org" , "robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org" , "festevam-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org" , "dan.j.williams-ral2JQCrhuEAvxtiuMwx3w@public.gmane.org" , "mark.rutland-5wv7dgnIgG8@public.gmane.org" , "catalin.marinas-5wv7dgnIgG8@public.gmane.org" , "will.deacon-5wv7dgnIgG8@public.gmane.org" , "l.stach-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org" , "martin.fuzzey-X8SyT9posyX3d/wEbhiU/g@public.gmane.org" , "kernel-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org" , "linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , "linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org" Return-path: In-Reply-To: <20200310073920.GR3335-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org> Content-Language: en-US Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-spi.vger.kernel.org On 2020/03/10 Sascha Hauer wrote: > On Tue, Mar 10, 2020 at 07:31:55PM +0800, Robin Gong wrote: > > Change to XCH mode even in dma mode, please refer to the below > > errata: > > https://eur01.safelinks.protection.outlook.com/?url=3Dhttps%3A%2F%2Fwww= . > > > nxp.com%2Fdocs%2Fen%2Ferrata%2FIMX6DQCE.pdf&data=3D02%7C01%7C > yibin.g > > > ong%40nxp.com%7Ccbabce268dfd4b0a0e2a08d7c4c62ff6%7C686ea1d3bc2b4c > 6fa92 > > > cd99c5c301635%7C0%7C1%7C637194227793913712&sdata=3DQ5N49T4jgX > TcdTzsB > > 3D0saK2%2Fzj0R4gnJcGR%2Bd70Fm4%3D&reserved=3D0 > > > > Signed-off-by: Robin Gong > > Acked-by: Mark Brown > > --- > > 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 index > > f4f28a4..842a86e 100644 > > --- a/drivers/spi/spi-imx.c > > +++ b/drivers/spi/spi-imx.c > > @@ -585,8 +585,9 @@ static int mx51_ecspi_prepare_transfer(struct > spi_imx_data *spi_imx, > > ctrl |=3D mx51_ecspi_clkdiv(spi_imx, t->speed_hz, &clk); > > spi_imx->spi_bus_clk =3D clk; > > > > + /* ERR009165: work in XHC mode as PIO */ > > if (spi_imx->usedma) > > - ctrl |=3D MX51_ECSPI_CTRL_SMC; > > + ctrl &=3D ~MX51_ECSPI_CTRL_SMC; >=20 > '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. >=20 > > > > writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL); > > > > @@ -612,12 +613,14 @@ static int mx51_ecspi_prepare_transfer(struct > > spi_imx_data *spi_imx, > > > > static void mx51_setup_wml(struct spi_imx_data *spi_imx) { > > + u32 tx_wml =3D 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) | >=20 > 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. >=20 > > 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 > > +1174,11 @@ static int spi_imx_dma_configure(struct spi_master *master) > > tx.direction =3D DMA_MEM_TO_DEV; > > tx.dst_addr =3D spi_imx->base_phys + MXC_CSPITXDATA; > > tx.dst_addr_width =3D buswidth; > > - tx.dst_maxburst =3D spi_imx->wml; > > + /* > > + * For ERR009165 with tx_wml =3D 0 could enlarge burst size to fifo s= ize > > + * to speed up fifo filling as possible. > > + */ > > + tx.dst_maxburst =3D spi_imx->devtype_data->fifo_size; > > ret =3D 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; >=20 > 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. >=20 > Sascha >=20 > -- > Pengutronix e.K. | > | > Steuerwalder Str. 21 | > https://eur01.safelinks.protection.outlook.com/?url=3Dhttp%3A%2F%2Fwww.pe > ngutronix.de%2F&data=3D02%7C01%7Cyibin.gong%40nxp.com%7Ccbabce2 > 68dfd4b0a0e2a08d7c4c62ff6%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0% > 7C1%7C637194227793913712&sdata=3DTL%2BheiNsYVPld3qyzWjF6yQZgH2 > HLdVFxzFeK3MupTc%3D&reserved=3D0 | > 31137 Hildesheim, Germany | Phone: +49-5121-206917-0 > | > Amtsgericht Hildesheim, HRA 2686 | Fax: > +49-5121-206917-5555 |