[EXT] Re: [PATCH 2/2] mmc: sdhci-esdhc-imx: calclute data timeout value based on clock
Luke Wang
ziniu.wang_1 at nxp.com
Tue Apr 8 19:35:27 PDT 2025
> -----Original Message-----
> From: Adrian Hunter <adrian.hunter at intel.com>
> Sent: Wednesday, April 9, 2025 1:59 AM
> To: Luke Wang <ziniu.wang_1 at nxp.com>; ulf.hansson at linaro.org; Bough
> Chen <haibo.chen at nxp.com>
> Cc: shawnguo at kernel.org; s.hauer at pengutronix.de;
> kernel at pengutronix.de; festevam at gmail.com; imx at lists.linux.dev; linux-
> mmc at vger.kernel.org; dl-S32 <S32 at nxp.com>; linux-arm-
> kernel at lists.infradead.org; linux-kernel at vger.kernel.org
> Subject: [EXT] Re: [PATCH 2/2] mmc: sdhci-esdhc-imx: calclute data timeout
> value based on clock
>
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>
> On 24/03/25 11:23, ziniu.wang_1 at nxp.com wrote:
> > From: Luke Wang <ziniu.wang_1 at nxp.com>
> >
> > Calclute data timeout value based on clock instead of using max value.
>
> And the subject:
>
> Calclute -> Calculate
>
> Presumably the driver has been working OK up until now with max value.
> Is there any particular reason to change it?
Hi Adrian,
Yes, the max value works fine. We want the value to align with the spec recommendation.
>
> >
> > Signed-off-by: Luke Wang <ziniu.wang_1 at nxp.com>
> > ---
> > drivers/mmc/host/sdhci-esdhc-imx.c | 15 +++++++++++----
> > 1 file changed, 11 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-
> esdhc-imx.c
> > index ff78a7c6a04c..e7316ecff64e 100644
> > --- a/drivers/mmc/host/sdhci-esdhc-imx.c
> > +++ b/drivers/mmc/host/sdhci-esdhc-imx.c
> > @@ -31,6 +31,7 @@
> > #include "cqhci.h"
> >
> > #define ESDHC_SYS_CTRL_DTOCV_MASK GENMASK(19, 16)
> > +#define ESDHC_SYS_CTRL_DTOCV_SHIFT 16
> > #define ESDHC_SYS_CTRL_IPP_RST_N BIT(23)
> > #define ESDHC_CTRL_D3CD 0x08
> > #define ESDHC_BURST_LEN_EN_INCR (1 << 27)
> > @@ -1387,12 +1388,16 @@ static unsigned int
> esdhc_get_max_timeout_count(struct sdhci_host *host)
> >
> > static void esdhc_set_timeout(struct sdhci_host *host, struct
> mmc_command *cmd)
> > {
> > - struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> > - struct pltfm_imx_data *imx_data = sdhci_pltfm_priv(pltfm_host);
> > + bool too_big = false;
> > + u8 count = sdhci_calc_timeout(host, cmd, &too_big);
> >
> > - /* use maximum timeout counter */
> > + /*
> > + * ESDHC_SYSTEM_CONTROL bit[23] used to control hardware reset
> > + * pin of the card. Write 0 to bit[23] will reset the card.
> > + * Only write DTOCV filed here.
>
> filed -> field ?
Yes, I will use --codespell to check next time.
>
> > + */
> > esdhc_clrset_le(host, ESDHC_SYS_CTRL_DTOCV_MASK,
> > - esdhc_is_usdhc(imx_data) ? 0xF0000 : 0xE0000,
> > + count << ESDHC_SYS_CTRL_DTOCV_SHIFT,
>
> Could use FIELD_PREP() here
OK
>
> > ESDHC_SYSTEM_CONTROL);
>
> Another way to do this could be to add SDHCI_TIMEOUT_CONTROL to
> esdhc_writeb_le() and remove esdhc_set_timeout(). That would
> avoid having to export sdhci_calc_timeout() and is perhaps
> slightly more consistent with other code in this driver.
> Probably look something like below:
>
> diff --git a/drivers/mmc/host/sdhci-esdhc-imx.c b/drivers/mmc/host/sdhci-
> esdhc-imx.c
> index ff78a7c6a04c..66477fc0ba82 100644
> --- a/drivers/mmc/host/sdhci-esdhc-imx.c
> +++ b/drivers/mmc/host/sdhci-esdhc-imx.c
> @@ -870,6 +870,16 @@ static void esdhc_writeb_le(struct sdhci_host *host,
> u8 val, int reg)
>
> esdhc_clrset_le(host, mask, new_val, reg);
> return;
> + case SDHCI_TIMEOUT_CONTROL:
> + /*
> + * ESDHC_SYSTEM_CONTROL bit[23] used to control hardware reset
> + * pin of the card. Write 0 to bit[23] will reset the card.
> + * Only write DTOCV field here.
> + */
> + esdhc_clrset_le(host, ESDHC_SYS_CTRL_DTOCV_MASK,
> + FIELD_PREP(ESDHC_SYS_CTRL_DTOCV_MASK, val),
> + ESDHC_SYSTEM_CONTROL);
> + return;
> case SDHCI_SOFTWARE_RESET:
> if (val & SDHCI_RESET_DATA)
> new_val = readl(host->ioaddr + SDHCI_HOST_CONTROL);
> @@ -1385,17 +1395,6 @@ static unsigned int
> esdhc_get_max_timeout_count(struct sdhci_host *host)
> return esdhc_is_usdhc(imx_data) ? 1 << 29 : 1 << 27;
> }
>
> -static void esdhc_set_timeout(struct sdhci_host *host, struct
> mmc_command *cmd)
> -{
> - struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> - struct pltfm_imx_data *imx_data = sdhci_pltfm_priv(pltfm_host);
> -
> - /* use maximum timeout counter */
> - esdhc_clrset_le(host, ESDHC_SYS_CTRL_DTOCV_MASK,
> - esdhc_is_usdhc(imx_data) ? 0xF0000 : 0xE0000,
> - ESDHC_SYSTEM_CONTROL);
> -}
> -
> static u32 esdhc_cqhci_irq(struct sdhci_host *host, u32 intmask)
> {
> int cmd_error = 0;
> @@ -1432,7 +1431,6 @@ static struct sdhci_ops sdhci_esdhc_ops = {
> .get_min_clock = esdhc_pltfm_get_min_clock,
> .get_max_timeout_count = esdhc_get_max_timeout_count,
> .get_ro = esdhc_pltfm_get_ro,
> - .set_timeout = esdhc_set_timeout,
> .set_bus_width = esdhc_pltfm_set_bus_width,
> .set_uhs_signaling = esdhc_set_uhs_signaling,
> .reset = esdhc_reset,
>
>
> > }
> >
> > @@ -1777,6 +1782,8 @@ static int sdhci_esdhc_imx_probe(struct
> platform_device *pdev)
> > * to distinguish the card type.
> > */
> > host->mmc_host_ops.init_card = usdhc_init_card;
> > +
> > + host->max_timeout_count = 0xF;
> > }
> >
> > if (imx_data->socdata->flags & ESDHC_FLAG_MAN_TUNING)
It's indeed a better way. I will send v2 patch.
Thanks
Luke
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