RE: [RESEND v6 07/13] spi: imx: remove ERR009165 workaround on i.mx6ul

[Robin Gong <yibin.gong@nxp.com>]

On 2020/03/10 Sascha Hauer <s.hauer@pengutronix.de> wrote:
> On Tue, Mar 10, 2020 at 07:31:56PM +0800, Robin Gong wrote:
> > 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.nx
> p.com%2F&amp;data=02%7C01%7Cyibin.gong%40nxp.com%7Cf73bfc11a68c4
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> 637194241755109112&amp;sdata=xzIUP8qZkrlDXX0yjTcUNZB6zDrevTdHFg1o4
> PZZd8E%3D&amp;reserved=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 | 50
> > +++++++++++++++++++++++++++++++++++++++++++++-----
> >  1 file changed, 45 insertions(+), 5 deletions(-)
> >
> > diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c index
> > 842a86e..f7ee2ec 100644
> > --- a/drivers/spi/spi-imx.c
> > +++ b/drivers/spi/spi-imx.c
> > @@ -57,6 +57,7 @@ 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 */
> >  };
> >
> >  struct spi_imx_data;
> > @@ -75,6 +76,11 @@ 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.nx
> p.com%2Fdocs%2Fen%2Ferrata%2FIMX6DQCE.pdf&amp;data=02%7C01%7Cyi
> bin.gong%40nxp.com%7Cf73bfc11a68c42f5f6d308d7c4c96efa%7C686ea1d3bc
> 2b4c6fa92cd99c5c301635%7C0%7C1%7C637194241755109112&amp;sdata=m
> uw4HL5nMDjREJwVd885Wrxka0moMaaZ%2BhJgsAgY3eo%3D&amp;reserved=
> 0
> > +	 */
> > +	bool tx_glitch_fixed;
> >  	enum spi_imx_devtype devtype;
> >  };
> >
> > @@ -128,7 +134,8 @@ static inline int is_imx35_cspi(struct
> > spi_imx_data *d)
> >
> >  static inline int is_imx51_ecspi(struct spi_imx_data *d)  {
> > -	return d->devtype_data->devtype == IMX51_ECSPI;
> > +	return d->devtype_data->devtype == IMX51_ECSPI ||
> > +	       d->devtype_data->devtype == IMX6UL_ECSPI;
> >  }
> 
> Erm, no. A i.MX51 ECSPI is a i.MX51 ECSPI and not a i.MX6UL ECSPI. If you want
> to handle them equally somewhere then explicitly test for i.MX6ul *and*
> i.MX51 there.
But all i.mx6 chips including i.MX53 ECSPI are almost same as i.MX51 ECSPI, and ERR00915 is fixed from i.mx6ul....
> 
> >
> >  static inline int is_imx53_ecspi(struct spi_imx_data *d) @@ -585,9
> > +592,16 @@ 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 */
> > -	if (spi_imx->usedma)
> > -		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) {
> > +		if (spi_imx->devtype_data->tx_glitch_fixed)
> > +			ctrl |= MX51_ECSPI_CTRL_SMC;
> > +		else
> > +			ctrl &= ~MX51_ECSPI_CTRL_SMC;
> > +	}
> 
> Changed again, but the PIO case still not honoured. This should look like
> 	if (spi_imx->usedma && spi_imx->devtype_data->tx_glitch_fixed)
> 		ctrl |= MX51_ECSPI_CTRL_SMC;
> 	else
> 		ctrl &= ~MX51_ECSPI_CTRL_SMC;
> 
Okay, will fix in v7.
> >
> >  	writel(ctrl, spi_imx->base + MX51_ECSPI_CTRL);
> >
> > @@ -615,6 +629,8 @@ 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;
> 
> That explains the variable introduced in the last patch, ok.
> 
> I have the impression that splitting up 06/13 and 07/13 into two patches
> doesn't make it easier to review.
But 06 is a errata for all i.mx6 legacy chips, while 07 is for i.mx6ul and newer chips which have been already fixed the HW issue. I think two patches are better.  
> 
> Sascha
> 
> 
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