On Thu, 24 Jun 2021 at 18:31, Al Cooper <alcooperx@xxxxxxxxx> wrote:
>
> When an eMMC device is being run in HS400 mode, any access to the
> RPMB device will cause the error message "mmc1: Invalid UHS-I mode
> selected". This happens as a result of tuning being disabled before
> RPMB access and then re-enabled after the RPMB access is complete.
> When tuning is re-enabled, the system has to switch from HS400
> to HS200 to do the tuning and then back to HS400. As part of
> sequence to switch from HS400 to HS200 the system is temporarily
> put into HS mode. When switching to HS mode, sdhci_get_preset_value()
> is called and does not have support for HS mode and prints the warning
> message and returns the preset for SDR12. The fix is to add support
> for MMC and SD HS modes to sdhci_get_preset_value().
>
> This can be reproduced on any system running eMMC in HS400 mode
> (not HS400ES) by using the "mmc" utility to run the following
> command: "mmc rpmb read-counter /dev/mmcblk0rpmb".
>
> Signed-off-by: Al Cooper <alcooperx@xxxxxxxxx>
I assume we want this for stable kernels, but it would be nice to add
a fixes tag as well.
Do you know if there is a specific commit that this fixes?
Kind regards
Uffe
> ---
> drivers/mmc/host/sdhci.c | 4 ++++
> drivers/mmc/host/sdhci.h | 1 +
> 2 files changed, 5 insertions(+)
>
> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
> index bf238ade1602..6b39126fbf06 100644
> --- a/drivers/mmc/host/sdhci.c
> +++ b/drivers/mmc/host/sdhci.c
> @@ -1812,6 +1812,10 @@ static u16 sdhci_get_preset_value(struct sdhci_host *host)
> u16 preset = 0;
>
> switch (host->timing) {
> + case MMC_TIMING_MMC_HS:
> + case MMC_TIMING_SD_HS:
> + preset = sdhci_readw(host, SDHCI_PRESET_FOR_HIGH_SPEED);
> + break;
> case MMC_TIMING_UHS_SDR12:
> preset = sdhci_readw(host, SDHCI_PRESET_FOR_SDR12);
> break;
> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
> index 0770c036e2ff..960fed78529e 100644
> --- a/drivers/mmc/host/sdhci.h
> +++ b/drivers/mmc/host/sdhci.h
> @@ -253,6 +253,7 @@
>
> /* 60-FB reserved */
>
> +#define SDHCI_PRESET_FOR_HIGH_SPEED 0x64
> #define SDHCI_PRESET_FOR_SDR12 0x66
> #define SDHCI_PRESET_FOR_SDR25 0x68
> #define SDHCI_PRESET_FOR_SDR50 0x6A
>
> base-commit: 7426cedc7dad67bf3c71ea6cc29ab7822e1a453f
> --
> 2.17.1
>
