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Message-ID: <7ca4554c58908618705768e01239409d19f83d17.camel@pengutronix.de>
Subject: Re: [PATCH v14 08/12] spi: imx: remove ERR009165 workaround on
 i.mx6ul
From:   Lucas Stach <l.stach@pengutronix.de>
To:     Robin Gong <yibin.gong@nxp.com>,
        "vkoul@kernel.org" <vkoul@kernel.org>,
        "mark.rutland@arm.com" <mark.rutland@arm.com>,
        "broonie@kernel.org" <broonie@kernel.org>,
        "robh+dt@kernel.org" <robh+dt@kernel.org>,
        "catalin.marinas@arm.com" <catalin.marinas@arm.com>,
        "will.deacon@arm.com" <will.deacon@arm.com>,
        "shawnguo@kernel.org" <shawnguo@kernel.org>,
        "festevam@gmail.com" <festevam@gmail.com>,
        "s.hauer@pengutronix.de" <s.hauer@pengutronix.de>,
        "martin.fuzzey@flowbird.group" <martin.fuzzey@flowbird.group>,
        "u.kleine-koenig@pengutronix.de" <u.kleine-koenig@pengutronix.de>,
        "dan.j.williams@intel.com" <dan.j.williams@intel.com>,
        "matthias.schiffer@ew.tq-group.com" 
        <matthias.schiffer@ew.tq-group.com>,
        "frieder.schrempf@kontron.de" <frieder.schrempf@kontron.de>,
        "m.felsch@pengutronix.de" <m.felsch@pengutronix.de>,
        Clark Wang <xiaoning.wang@nxp.com>
Cc:     "devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "linux-spi@vger.kernel.org" <linux-spi@vger.kernel.org>,
        dl-linux-imx <linux-imx@nxp.com>,
        "kernel@pengutronix.de" <kernel@pengutronix.de>,
        "dmaengine@vger.kernel.org" <dmaengine@vger.kernel.org>,
        "linux-arm-kernel@lists.infradead.org" 
        <linux-arm-kernel@lists.infradead.org>
Date:   Mon, 12 Jul 2021 11:30:58 +0200
In-Reply-To: <VE1PR04MB668852203A2920C6C9E9E3CF89159@VE1PR04MB6688.eurprd04.prod.outlook.com>
References: <1617809456-17693-1-git-send-email-yibin.gong@nxp.com>
         <1617809456-17693-9-git-send-email-yibin.gong@nxp.com>
         <dfa12f89f112966197518aa8df25cb47d69b30f7.camel@pengutronix.de>
         <VE1PR04MB668852203A2920C6C9E9E3CF89159@VE1PR04MB6688.eurprd04.prod.outlook.com>
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Am Montag, dem 12.07.2021 um 03:48 +0000 schrieb Robin Gong:
> On 09/07/21 17:42 Lucas Stach <l.stach@pengutronix.de> wrote: 
> > Am Mittwoch, dem 07.04.2021 um 23:30 +0800 schrieb Robin Gong:
> > > ERR009165 fixed on i.mx6ul/6ull/6sll. All other i.mx6/7 and i.mx8m/8mm
> > > still need this errata. Please refer to nxp official errata document
> > > from
> > https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.n
> > xp.com%2F&amp;data=04%7C01%7Cyibin.gong%40nxp.com%7C48156bc93d
> > c84ac26e9d08d942bdc0ac%7C686ea1d3bc2b4c6fa92cd99c5c301635%7C0%
> > 7C1%7C637614205017900475%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4
> > wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&a
> > mp;sdata=keYQubzt1jWrKhaxXr40RL41vzFuIn7x1Sasa3p%2F9Xo%3D&amp;res
> > erved=0 .
> > > 
> > > For removing workaround on those chips. Add new i.mx6ul type.
> > > 
> > > Signed-off-by: Robin Gong <yibin.gong@nxp.com>
> > > Acked-by: Mark Brown <broonie@kernel.org>
> > > ---
> > >  drivers/spi/spi-imx.c | 47
> > > +++++++++++++++++++++++++++++++++++++++++++----
> > >  1 file changed, 43 insertions(+), 4 deletions(-)
> > > 
> > > diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c index
> > > cf235b9..d18ee25 100644
> > > --- a/drivers/spi/spi-imx.c
> > > +++ b/drivers/spi/spi-imx.c
> > > @@ -59,6 +59,7 @@ enum spi_imx_devtype {
> > >  	IMX35_CSPI,	/* CSPI on all i.mx except above */
> > >  	IMX51_ECSPI,	/* ECSPI on i.mx51 */
> > >  	IMX53_ECSPI,	/* ECSPI on i.mx53 and later */
> > > +	IMX6UL_ECSPI,	/* ERR009165 fix from i.mx6ul */
> > 
> > This patch could be a lot smaller if you didn't introduce a new devtype. You
> > could just use the IMX51_ECSPI in imx6ul_ecspi_devtype_data, as all you care
> > about as a relevant difference is the tx_glitch_fixed property, which isn't tied
> > to the devtype.
> I knew tx_glitch_fixed was enough but I still prefer to add new 'IMX6UL_ECSPI' because
> we can clearly choose the right IP which has fix the issue while legacy IMX51 if it's not
> fixed by dts.
> 
Sorry, I don't follow this reasoning. You are not using the new
IMX6UL_ECSPI devtype in any way in this patch, other than a single
location, where you just handle it the same as the IMX51_ECSPI devtype.

Regards,
Lucas

>  
> 
> > >  };
> > > 
> > >  struct spi_imx_data;
> > > @@ -78,6 +79,11 @@ struct spi_imx_devtype_data {
> > >  	bool has_slavemode;
> > >  	unsigned int fifo_size;
> > >  	bool dynamic_burst;
> > > +	/*
> > > +	 * ERR009165 fixed or not:
> > > +	 *
> > https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.n
> > xp.com%2Fdocs%2Fen%2Ferrata%2FIMX6DQCE.pdf&amp;data=04%7C01%7C
> > yibin.gong%40nxp.com%7C48156bc93dc84ac26e9d08d942bdc0ac%7C686ea
> > 1d3bc2b4c6fa92cd99c5c301635%7C0%7C1%7C637614205017900475%7CU
> > nknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6
> > Ik1haWwiLCJXVCI6Mn0%3D%7C1000&amp;sdata=J9iZb93uN1VEriN%2F2GAE
> > TWxdv4n%2FD6ZXteMCFkB8KHM%3D&amp;reserved=0
> > > +	 */
> > > +	bool tx_glitch_fixed;
> > >  	enum spi_imx_devtype devtype;
> > >  };
> > > 
> > > @@ -134,6 +140,11 @@ static inline int is_imx51_ecspi(struct spi_imx_data
> > *d)
> > >  	return d->devtype_data->devtype == IMX51_ECSPI;  }
> > > 
> > > +static inline int is_imx6ul_ecspi(struct spi_imx_data *d) {
> > > +	return d->devtype_data->devtype == IMX6UL_ECSPI; }
> > > +
> > >  static inline int is_imx53_ecspi(struct spi_imx_data *d)  {
> > >  	return d->devtype_data->devtype == IMX53_ECSPI; @@ -593,8 +604,14
> > @@
> > > 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;
> > > 
> > > -	/* ERR009165: work in XHC mode as PIO */
> > > -	ctrl &= ~MX51_ECSPI_CTRL_SMC;
> > > +	/*
> > > +	 * ERR009165: work in XHC mode instead of SMC as PIO on the chips
> > > +	 * before i.mx6ul.
> > > +	 */
> > > +	if (spi_imx->usedma && spi_imx->devtype_data->tx_glitch_fixed)
> > > +		ctrl |= MX51_ECSPI_CTRL_SMC;
> > > +	else
> > > +		ctrl &= ~MX51_ECSPI_CTRL_SMC;
> > > 
> > >  	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
> > > 
> > > @@ -620,12 +637,16 @@ 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 = 0;
> > > +
> > > +	if (spi_imx->devtype_data->tx_glitch_fixed)
> > > +		tx_wml = spi_imx->wml;
> > >  	/*
> > >  	 * 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(0) |
> > > +		MX51_ECSPI_DMA_TX_WML(tx_wml) |
> > >  		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);
> > @@ -1019,6
> > > +1040,23 @@ static struct spi_imx_devtype_data
> > imx53_ecspi_devtype_data = {
> > >  	.devtype = IMX53_ECSPI,
> > >  };
> > > 
> > > +static struct spi_imx_devtype_data imx6ul_ecspi_devtype_data = {
> > > +	.intctrl = mx51_ecspi_intctrl,
> > > +	.prepare_message = mx51_ecspi_prepare_message,
> > > +	.prepare_transfer = mx51_ecspi_prepare_transfer,
> > > +	.trigger = mx51_ecspi_trigger,
> > > +	.rx_available = mx51_ecspi_rx_available,
> > > +	.reset = mx51_ecspi_reset,
> > > +	.setup_wml = mx51_setup_wml,
> > > +	.fifo_size = 64,
> > > +	.has_dmamode = true,
> > > +	.dynamic_burst = true,
> > > +	.has_slavemode = true,
> > > +	.tx_glitch_fixed = true,
> > > +	.disable = mx51_ecspi_disable,
> > > +	.devtype = IMX6UL_ECSPI,
> > > +};
> > > +
> > >  static const struct of_device_id spi_imx_dt_ids[] = {
> > >  	{ .compatible = "fsl,imx1-cspi", .data = &imx1_cspi_devtype_data, },
> > >  	{ .compatible = "fsl,imx21-cspi", .data = &imx21_cspi_devtype_data,
> > > }, @@ -1027,6 +1065,7 @@ static const struct of_device_id spi_imx_dt_ids[]
> > = {
> > >  	{ .compatible = "fsl,imx35-cspi", .data = &imx35_cspi_devtype_data, },
> > >  	{ .compatible = "fsl,imx51-ecspi", .data = &imx51_ecspi_devtype_data, },
> > >  	{ .compatible = "fsl,imx53-ecspi", .data =
> > > &imx53_ecspi_devtype_data, },
> > > +	{ .compatible = "fsl,imx6ul-ecspi", .data =
> > > +&imx6ul_ecspi_devtype_data, },
> > >  	{ /* sentinel */ }
> > >  };
> > >  MODULE_DEVICE_TABLE(of, spi_imx_dt_ids); @@ -1604,7 +1643,7 @@
> > static
> > > int spi_imx_probe(struct platform_device *pdev)
> > >  	spi_imx->bitbang.master->mode_bits = SPI_CPOL | SPI_CPHA |
> > SPI_CS_HIGH \
> > >  					     | SPI_NO_CS;
> > >  	if (is_imx35_cspi(spi_imx) || is_imx51_ecspi(spi_imx) ||
> > > -	    is_imx53_ecspi(spi_imx))
> > > +	    is_imx53_ecspi(spi_imx) || is_imx6ul_ecspi(spi_imx))
> > >  		spi_imx->bitbang.master->mode_bits |= SPI_LOOP | SPI_READY;
> > > 
> > >  	spi_imx->spi_drctl = spi_drctl;
> > 
>