On Fri, 6 May 2022 at 11:18, Sebastian Reichel
<sebastian.reichel@xxxxxxxxxxxxx> wrote:
>
> Hi,
>
> On Fri, May 06, 2022 at 10:52:42AM +0200, Ulf Hansson wrote:
> > On Wed, 4 May 2022 at 23:33, Sebastian Reichel
> > <sebastian.reichel@xxxxxxxxxxxxx> wrote:
> > >
> > > From: Yifeng Zhao <yifeng.zhao@xxxxxxxxxxxxxx>
> > >
> > > The reset function build in the SDHCI will not reset the logic
> > > circuit related to the tuning function, which may cause data
> > > reading errors. Resetting the complete SDHCI controller through
> > > the reset controller fixes the issue.
> > >
> > > Signed-off-by: Yifeng Zhao <yifeng.zhao@xxxxxxxxxxxxxx>
> > > [rebase, use optional variant of reset getter]
> > > Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx>
> > > Signed-off-by: Sebastian Reichel <sebastian.reichel@xxxxxxxxxxxxx>
> >
> > I think this needs a corresponding update of the DT docs. Otherwise
> > this looks good to me.
>
> I do have 'resets' and 'reset-names' properties in the rk3588s.dtsi
> for the sdhci interface and 'make dtbs_check' did not complain about
> anything but missing 'arm,sdei-1.0' compatible for the rk3588 EVB
> (sdei binding has not yet been converted to yaml). Thus I assume the
> resets property is inferred from somewhere?
I don't think it should, but I may be wrong.
How about if you extend the example in the DT doc with a reset
property, will that cause the DT tools to complain?
Kind regards
Uffe
>
> -- Sebastian
>
> >
> > Kind regards
> > Uffe
> >
> > > ---
> > > drivers/mmc/host/sdhci-of-dwcmshc.c | 26 +++++++++++++++++++++++++-
> > > 1 file changed, 25 insertions(+), 1 deletion(-)
> > >
> > > diff --git a/drivers/mmc/host/sdhci-of-dwcmshc.c b/drivers/mmc/host/sdhci-of-dwcmshc.c
> > > index bac874ab0b33..3a1b5ba36405 100644
> > > --- a/drivers/mmc/host/sdhci-of-dwcmshc.c
> > > +++ b/drivers/mmc/host/sdhci-of-dwcmshc.c
> > > @@ -15,6 +15,7 @@
> > > #include <linux/module.h>
> > > #include <linux/of.h>
> > > #include <linux/of_device.h>
> > > +#include <linux/reset.h>
> > > #include <linux/sizes.h>
> > >
> > > #include "sdhci-pltfm.h"
> > > @@ -63,6 +64,7 @@
> > > struct rk3568_priv {
> > > /* Rockchip specified optional clocks */
> > > struct clk_bulk_data rockchip_clks[RK3568_MAX_CLKS];
> > > + struct reset_control *reset;
> > > u8 txclk_tapnum;
> > > };
> > >
> > > @@ -255,6 +257,21 @@ static void dwcmshc_rk3568_set_clock(struct sdhci_host *host, unsigned int clock
> > > sdhci_writel(host, extra, DWCMSHC_EMMC_DLL_STRBIN);
> > > }
> > >
> > > +static void rk35xx_sdhci_reset(struct sdhci_host *host, u8 mask)
> > > +{
> > > + struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
> > > + struct dwcmshc_priv *dwc_priv = sdhci_pltfm_priv(pltfm_host);
> > > + struct rk35xx_priv *priv = dwc_priv->priv;
> > > +
> > > + if (mask & SDHCI_RESET_ALL && priv->reset) {
> > > + reset_control_assert(priv->reset);
> > > + udelay(1);
> > > + reset_control_deassert(priv->reset);
> > > + }
> > > +
> > > + sdhci_reset(host, mask);
> > > +}
> > > +
> > > static const struct sdhci_ops sdhci_dwcmshc_ops = {
> > > .set_clock = sdhci_set_clock,
> > > .set_bus_width = sdhci_set_bus_width,
> > > @@ -269,7 +286,7 @@ static const struct sdhci_ops sdhci_dwcmshc_rk3568_ops = {
> > > .set_bus_width = sdhci_set_bus_width,
> > > .set_uhs_signaling = dwcmshc_set_uhs_signaling,
> > > .get_max_clock = sdhci_pltfm_clk_get_max_clock,
> > > - .reset = sdhci_reset,
> > > + .reset = rk35xx_sdhci_reset,
> > > .adma_write_desc = dwcmshc_adma_write_desc,
> > > };
> > >
> > > @@ -292,6 +309,13 @@ static int dwcmshc_rk3568_init(struct sdhci_host *host, struct dwcmshc_priv *dwc
> > > int err;
> > > struct rk3568_priv *priv = dwc_priv->priv;
> > >
> > > + priv->reset = devm_reset_control_array_get_optional_exclusive(mmc_dev(host->mmc));
> > > + if (IS_ERR(priv->reset)) {
> > > + err = PTR_ERR(priv->reset);
> > > + dev_err(mmc_dev(host->mmc), "failed to get reset control %d\n", err);
> > > + return err;
> > > + }
> > > +
> > > priv->rockchip_clks[0].id = "axi";
> > > priv->rockchip_clks[1].id = "block";
> > > priv->rockchip_clks[2].id = "timer";
> > > --
> > > 2.35.1
> > >
