Re: [PATCH v2] mmc: sdhci-of-arasan: Support for emmc hardware reset

[Ulf Hansson]

On Mon, 7 Oct 2024 at 11:54, Paul Alvin <alvin.paulp@xxxxxxx> wrote:
>
> Add hw_reset callback to support emmc hardware reset, this callback get
> called from the mmc core only when "cap-mmc-hw-reset" property is
> defined in the DT.
>
> Signed-off-by: Paul Alvin <alvin.paulp@xxxxxxx>

Applied for next, thanks!

Kind regards
Uffe


> ---
>
> Changes in v2:
> - Updated the CC list
>
>  drivers/mmc/host/sdhci-of-arasan.c | 18 ++++++++++++++++++
>  1 file changed, 18 insertions(+)
>
> diff --git a/drivers/mmc/host/sdhci-of-arasan.c b/drivers/mmc/host/sdhci-of-arasan.c
> index 5edd024347bd..0cb05bdec34d 100644
> --- a/drivers/mmc/host/sdhci-of-arasan.c
> +++ b/drivers/mmc/host/sdhci-of-arasan.c
> @@ -76,6 +76,8 @@
>  #define FREQSEL_225M_200M              0x7
>  #define PHY_DLL_TIMEOUT_MS             100
>
> +#define SDHCI_HW_RST_EN                BIT(4)
> +
>  /* Default settings for ZynqMP Clock Phases */
>  #define ZYNQMP_ICLK_PHASE {0, 63, 63, 0, 63,  0,   0, 183, 54,  0, 0}
>  #define ZYNQMP_OCLK_PHASE {0, 72, 60, 0, 60, 72, 135, 48, 72, 135, 0}
> @@ -475,6 +477,21 @@ static void sdhci_arasan_reset(struct sdhci_host *host, u8 mask)
>         }
>  }
>
> +static void sdhci_arasan_hw_reset(struct sdhci_host *host)
> +{
> +       u8 reg;
> +
> +       reg = sdhci_readb(host, SDHCI_POWER_CONTROL);
> +       reg |= SDHCI_HW_RST_EN;
> +       sdhci_writeb(host, reg, SDHCI_POWER_CONTROL);
> +       /* As per eMMC spec, minimum 1us is required but give it 2us for good measure */
> +       usleep_range(2, 5);
> +       reg &= ~SDHCI_HW_RST_EN;
> +       sdhci_writeb(host, reg, SDHCI_POWER_CONTROL);
> +       /* As per eMMC spec, minimum 200us is required but give it 300us for good measure */
> +       usleep_range(300, 500);
> +}
> +
>  static int sdhci_arasan_voltage_switch(struct mmc_host *mmc,
>                                        struct mmc_ios *ios)
>  {
> @@ -505,6 +522,7 @@ static const struct sdhci_ops sdhci_arasan_ops = {
>         .reset = sdhci_arasan_reset,
>         .set_uhs_signaling = sdhci_set_uhs_signaling,
>         .set_power = sdhci_set_power_and_bus_voltage,
> +       .hw_reset = sdhci_arasan_hw_reset,
>  };
>
>  static u32 sdhci_arasan_cqhci_irq(struct sdhci_host *host, u32 intmask)
> --
> 2.17.1
>