[U-Boot] [PATCH V2 02/13] mmc: tmio: Switch to clock framework

Masahiro Yamada yamada.masahiro at socionext.com
Thu Nov 1 11:38:53 UTC 2018


On Thu, Nov 1, 2018 at 6:39 PM Marek Vasut <marek.vasut at gmail.com> wrote:
>
> Switch the driver to using clk_get_rate()/clk_set_rate() instead of
> caching the mclk frequency in it's private data. This is required on
> the SDHI variant of the controller, where the upstream mclk need to
> be adjusted when using UHS modes.

No.

What you need to do is move tmio_sd_set_clk_rate()
to a platform hook.

See Linux commit 0196c8db8363f7627df6f78615271ae0ba430500




> Platforms which do not support clock framework or do not support it
> in eg. SPL default to 100 MHz clock.

This is bad.
You never know whether the default clock is 100 MHz or not.



> Signed-off-by: Marek Vasut <marek.vasut+renesas at gmail.com>
> Cc: Masahiro Yamada <yamada.masahiro at socionext.com>
> ---
> V2: Fix build on certain platforms using SPL without clock framework
> ---
>  drivers/mmc/renesas-sdhi.c | 14 ++++++--------
>  drivers/mmc/tmio-common.c  | 21 ++++++++++++++++++---
>  drivers/mmc/tmio-common.h  |  2 +-
>  drivers/mmc/uniphier-sd.c  | 13 +++++--------
>  4 files changed, 30 insertions(+), 20 deletions(-)
>
> diff --git a/drivers/mmc/renesas-sdhi.c b/drivers/mmc/renesas-sdhi.c
> index f8dc5f57ce..1590f496d7 100644
> --- a/drivers/mmc/renesas-sdhi.c
> +++ b/drivers/mmc/renesas-sdhi.c
> @@ -333,7 +333,6 @@ static int renesas_sdhi_probe(struct udevice *dev)
>         struct tmio_sd_priv *priv = dev_get_priv(dev);
>         u32 quirks = dev_get_driver_data(dev);
>         struct fdt_resource reg_res;
> -       struct clk clk;
>         DECLARE_GLOBAL_DATA_PTR;
>         int ret;
>
> @@ -350,22 +349,21 @@ static int renesas_sdhi_probe(struct udevice *dev)
>                         quirks |= TMIO_SD_CAP_16BIT;
>         }
>
> -       ret = clk_get_by_index(dev, 0, &clk);
> +       ret = clk_get_by_index(dev, 0, &priv->clk);
>         if (ret < 0) {
>                 dev_err(dev, "failed to get host clock\n");
>                 return ret;
>         }
>
>         /* set to max rate */
> -       priv->mclk = clk_set_rate(&clk, ULONG_MAX);
> -       if (IS_ERR_VALUE(priv->mclk)) {
> +       ret = clk_set_rate(&priv->clk, 200000000);
> +       if (ret < 0) {
>                 dev_err(dev, "failed to set rate for host clock\n");
> -               clk_free(&clk);
> -               return priv->mclk;
> +               clk_free(&priv->clk);
> +               return ret;
>         }
>
> -       ret = clk_enable(&clk);
> -       clk_free(&clk);
> +       ret = clk_enable(&priv->clk);
>         if (ret) {
>                 dev_err(dev, "failed to enable host clock\n");
>                 return ret;
> diff --git a/drivers/mmc/tmio-common.c b/drivers/mmc/tmio-common.c
> index 5f927c6150..611fc5fdbc 100644
> --- a/drivers/mmc/tmio-common.c
> +++ b/drivers/mmc/tmio-common.c
> @@ -551,16 +551,28 @@ static void tmio_sd_set_ddr_mode(struct tmio_sd_priv *priv,
>         tmio_sd_writel(priv, tmp, TMIO_SD_IF_MODE);
>  }
>
> +static ulong tmio_sd_clk_get_rate(struct tmio_sd_priv *priv)
> +{
> +#if CONFIG_IS_ENABLED(CLK)
> +       return clk_get_rate(&priv->clk);
> +#else
> +       return 100000000;
> +#endif
> +}
>  static void tmio_sd_set_clk_rate(struct tmio_sd_priv *priv,
>                                      struct mmc *mmc)
>  {
>         unsigned int divisor;
>         u32 val, tmp;
> +       ulong mclk;
>
>         if (!mmc->clock)
>                 return;
>
> -       divisor = DIV_ROUND_UP(priv->mclk, mmc->clock);
> +       mclk = tmio_sd_clk_get_rate(priv);
> +
> +       divisor = DIV_ROUND_UP(mclk, mmc->clock);
>
>         if (divisor <= 1)
>                 val = (priv->caps & TMIO_SD_CAP_RCAR) ?
> @@ -704,6 +716,7 @@ int tmio_sd_probe(struct udevice *dev, u32 quirks)
>         struct tmio_sd_priv *priv = dev_get_priv(dev);
>         struct mmc_uclass_priv *upriv = dev_get_uclass_priv(dev);
>         fdt_addr_t base;
> +       ulong mclk;
>         int ret;
>
>         base = devfdt_get_addr(dev);
> @@ -744,10 +757,12 @@ int tmio_sd_probe(struct udevice *dev, u32 quirks)
>
>         tmio_sd_host_init(priv);
>
> +       mclk = tmio_sd_clk_get_rate(priv);
> +
>         plat->cfg.voltages = MMC_VDD_165_195 | MMC_VDD_32_33 | MMC_VDD_33_34;
> -       plat->cfg.f_min = priv->mclk /
> +       plat->cfg.f_min = mclk /
>                         (priv->caps & TMIO_SD_CAP_DIV1024 ? 1024 : 512);
> -       plat->cfg.f_max = priv->mclk;
> +       plat->cfg.f_max = mclk;
>         plat->cfg.b_max = U32_MAX; /* max value of TMIO_SD_SECCNT */
>
>         upriv->mmc = &plat->mmc;
> diff --git a/drivers/mmc/tmio-common.h b/drivers/mmc/tmio-common.h
> index 792b1ba5ae..fcdee4df57 100644
> --- a/drivers/mmc/tmio-common.h
> +++ b/drivers/mmc/tmio-common.h
> @@ -117,7 +117,7 @@ struct tmio_sd_plat {
>
>  struct tmio_sd_priv {
>         void __iomem                    *regbase;
> -       unsigned long                   mclk;
> +       struct clk                      clk;
>         unsigned int                    version;
>         u32                             caps;
>  #define TMIO_SD_CAP_NONREMOVABLE       BIT(0)  /* Nonremovable e.g. eMMC */
> diff --git a/drivers/mmc/uniphier-sd.c b/drivers/mmc/uniphier-sd.c
> index 813c28494c..870d1c9929 100644
> --- a/drivers/mmc/uniphier-sd.c
> +++ b/drivers/mmc/uniphier-sd.c
> @@ -38,28 +38,25 @@ static int uniphier_sd_probe(struct udevice *dev)
>         struct clk clk;
>         int ret;
>
> -       ret = clk_get_by_index(dev, 0, &clk);
> +       ret = clk_get_by_index(dev, 0, &priv->clk);
>         if (ret < 0) {
>                 dev_err(dev, "failed to get host clock\n");
>                 return ret;
>         }
>
>         /* set to max rate */
> -       priv->mclk = clk_set_rate(&clk, ULONG_MAX);
> -       if (IS_ERR_VALUE(priv->mclk)) {
> +       ret = clk_set_rate(&priv->clk, ULONG_MAX);
> +       if (ret < 0) {
>                 dev_err(dev, "failed to set rate for host clock\n");
> -               clk_free(&clk);
> -               return priv->mclk;
> +               clk_free(&priv->clk);
> +               return ret;
>         }
>
>         ret = clk_enable(&clk);
> -       clk_free(&clk);
>         if (ret) {
>                 dev_err(dev, "failed to enable host clock\n");
>                 return ret;
>         }
> -#else
> -       priv->mclk = 100000000;
>  #endif
>
>         return tmio_sd_probe(dev, 0);
> --
> 2.18.0
>
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--
Best Regards
Masahiro Yamada


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