On Tue, Mar 19, 2019 at 11:12:59AM +0100, Wolfram Sang wrote:
> R-Car Gen2 has two different SDHI incarnations in the same chip. The
> older one does not support the recently introduced 32 bit register
> access to the block count register. Make sure we use this feature only
> after the first known version.
>
> Thanks to the Renesas Testing team for this bug report!
>
> Fixes:5603731a15ef ("mmc: tmio: fix access width of Block Count Register")
> Reported-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@xxxxxxxxxxx>
> Signed-off-by: Wolfram Sang <wsa+renesas@xxxxxxxxxxxxxxxxxxxx>
Reviewed-by: Simon Horman <horms+renesas@xxxxxxxxxxxx>
> ---
>
> I could reproduce the issue on my Renesas Lager board (R-Car H2) and this patch
> fixes the issue for me. Still, if we could confirmation from the testing team,
> this would be awesome to have before applying, I think.
>
> drivers/mmc/host/renesas_sdhi_core.c | 8 +++++++-
> 1 file changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/host/renesas_sdhi_core.c b/drivers/mmc/host/renesas_sdhi_core.c
> index 71e13844df6c..8742e27e4e8b 100644
> --- a/drivers/mmc/host/renesas_sdhi_core.c
> +++ b/drivers/mmc/host/renesas_sdhi_core.c
> @@ -641,6 +641,7 @@ int renesas_sdhi_probe(struct platform_device *pdev,
> struct renesas_sdhi *priv;
> struct resource *res;
> int irq, ret, i;
> + u16 ver;
>
> of_data = of_device_get_match_data(&pdev->dev);
>
> @@ -773,12 +774,17 @@ int renesas_sdhi_probe(struct platform_device *pdev,
> if (ret)
> goto efree;
>
> + ver = sd_ctrl_read16(host, CTL_VERSION);
> + /* GEN2_SDR104 is first known SDHI to use 32bit block count */
> + if (ver < SDHI_VER_GEN2_SDR104 && mmc_data->max_blk_count > U16_MAX)
> + mmc_data->max_blk_count = U16_MAX;
> +
> ret = tmio_mmc_host_probe(host);
> if (ret < 0)
> goto edisclk;
>
> /* One Gen2 SDHI incarnation does NOT have a CBSY bit */
> - if (sd_ctrl_read16(host, CTL_VERSION) == SDHI_VER_GEN2_SDR50)
> + if (ver == SDHI_VER_GEN2_SDR50)
> mmc_data->flags &= ~TMIO_MMC_HAVE_CBSY;
>
> /* Enable tuning iff we have an SCC and a supported mode */
> --
> 2.11.0
>
