atmel_sdhci: SDMMC_CD pin still needed for card detection despite EMMC set to non-removable

[Eugen Hristev]

Hi Zixun,

I cannot apply your patch, there is some error.
can you use

git send-email yourfile.patch --to u-boot at lists.denx.de --to 
eugen.hristev at collabora.com

such that I can grab it from patchwork ?

Thanks,
Eugen


On 5/4/23 17:59, Zixun Li wrote:
>>   Can't we do this in a different place?
>> When we parse the DT for example. If the card is non-removable, this is described as a property in the DT.
>> In this way you don't have to recreate all the below code from the common sdhci_get_cd, and you avoid rewriting the MC1R every time the get_cd is called.
> 
> The problem is inside sdhci_init() there is a sdhci_reset(), FCD bit will lost if we set it too early.
> 
> Then I've looked at the kernel driver, setting this bit is also a workaround of SAMA5D2 series, who doesn't drive CMD if using CD GPIO line.
> 
> https://github.com/linux4sam/linux-at91/blob/068eaa6b4b087b3a86fc4624d0f4083844e93f1c/drivers/mmc/host/sdhci-of-at91.c#L551
> 
> I've refactored the code, setting FCD bit after sdhci_probe() with a separate function to make the purpose more clear.
> 
> 
>  From 90177e7af8226b88dfbfc08639f768881562a3a2 Mon Sep 17 00:00:00 2001
> From: Zixun LI <zli at ogga.fr>
> Date: Thu, 4 May 2023 16:30:41 +0200
> Subject: [PATCH] atmel_sdhci: Force card-detect if MMC_CAP_NONREMOVABLE.
> 
> ---
>   drivers/mmc/atmel_sdhci.c | 40 +++++++++++++++++++++++++++++++++++++--
>   1 file changed, 38 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/mmc/atmel_sdhci.c b/drivers/mmc/atmel_sdhci.c
> index 37b0beeed4..ae56266f57 100644
> --- a/drivers/mmc/atmel_sdhci.c
> +++ b/drivers/mmc/atmel_sdhci.c
> @@ -15,6 +15,9 @@
>   #define ATMEL_SDHC_MIN_FREQ    400000
>   #define ATMEL_SDHC_GCK_RATE    240000000
> 
> +#define ATMEL_SDHC_MC1R 0x204
> +#define ATMEL_SDHC_MC1R_FCD    0x80
> +
>   #ifndef CONFIG_DM_MMC
>   int atmel_sdhci_init(void *regbase, u32 id)
>   {
> @@ -52,11 +55,38 @@ struct atmel_sdhci_plat {
>          struct mmc mmc;
>   };
> 
> +static void atmel_sdhci_config_fcd(struct sdhci_host *host)
> +{
> +       u8 mc1r;
> +
> +       /* If nonremovable, assume that the card is always present.
> +        *
> +        * WA: SAMA5D2 doesn't drive CMD if using CD GPIO line.
> +        */
> +       if ((host->mmc->cfg->host_caps & MMC_CAP_NONREMOVABLE)
> +#if CONFIG_IS_ENABLED(DM_GPIO)
> +               || dm_gpio_get_value(&host->cd_gpio) >= 0
> +#endif
> +          )
> +       {
> +               sdhci_readb(host, ATMEL_SDHC_MC1R);
> +               mc1r |= ATMEL_SDHC_MC1R_FCD;
> +               sdhci_writeb(host, mc1r, ATMEL_SDHC_MC1R);
> +       }
> +}
> +
>   static int atmel_sdhci_deferred_probe(struct sdhci_host *host)
>   {
>          struct udevice *dev = host->mmc->dev;
> +       int ret;
> 
> -       return sdhci_probe(dev);
> +       ret = sdhci_probe(dev);
> +       if (ret)
> +               return ret;
> +
> +       atmel_sdhci_config_fcd(host);
> +
> +       return 0;
>   }
> 
>   static const struct sdhci_ops atmel_sdhci_ops = {
> @@ -120,7 +150,13 @@ static int atmel_sdhci_probe(struct udevice *dev)
> 
>          clk_free(&clk);
> 
> -       return sdhci_probe(dev);
> +       ret = sdhci_probe(dev);
> +       if (ret)
> +               return ret;
> +
> +       atmel_sdhci_config_fcd(host);
> +
> +       return 0;
>   }
> 
>   static int atmel_sdhci_bind(struct udevice *dev)
> --
> 2.40.1
>