Re: [PATCH v2 1/3] mmc: sunxi: Disable HS-DDR mode for H5 eMMC controller by default

[Ulf Hansson]

On Tue, 5 Feb 2019 at 16:42, Chen-Yu Tsai <wens@xxxxxxxx> wrote:
>
> Some H5 boards seem to not have proper trace lengths for eMMC to be able
> to use the default setting for the delay chains under HS-DDR mode. These
> include the Bananapi M2+ H5 and NanoPi NEO Core2. However the Libre
> Computer ALL-H3-CC-H5 works just fine.
>
> For the H5 (at least for now), default to not enabling HS-DDR modes in
> the driver, and expect the device tree to signal HS-DDR capability on
> boards that work.
>
> Reported-by: Chris Blake <chrisrblake93@xxxxxxxxx>
> Fixes: 07bafc1e3536 ("mmc: sunxi: Use new timing mode for A64 eMMC controller")
> Cc: <stable@xxxxxxxxxxxxxxx>
> Acked-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxx>
> Signed-off-by: Chen-Yu Tsai <wens@xxxxxxxx>

Applied for fixes, thanks!

Kind regards
Uffe


> ---
>  drivers/mmc/host/sunxi-mmc.c | 11 ++++++++++-
>  1 file changed, 10 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/mmc/host/sunxi-mmc.c b/drivers/mmc/host/sunxi-mmc.c
> index 279e326e397e..7415af8c8ff6 100644
> --- a/drivers/mmc/host/sunxi-mmc.c
> +++ b/drivers/mmc/host/sunxi-mmc.c
> @@ -1399,7 +1399,16 @@ static int sunxi_mmc_probe(struct platform_device *pdev)
>         mmc->caps              |= MMC_CAP_MMC_HIGHSPEED | MMC_CAP_SD_HIGHSPEED |
>                                   MMC_CAP_ERASE | MMC_CAP_SDIO_IRQ;
>
> -       if (host->cfg->clk_delays || host->use_new_timings)
> +       /*
> +        * Some H5 devices do not have signal traces precise enough to
> +        * use HS DDR mode for their eMMC chips.
> +        *
> +        * We still enable HS DDR modes for all the other controller
> +        * variants that support them.
> +        */
> +       if ((host->cfg->clk_delays || host->use_new_timings) &&
> +           !of_device_is_compatible(pdev->dev.of_node,
> +                                    "allwinner,sun50i-h5-emmc"))
>                 mmc->caps      |= MMC_CAP_1_8V_DDR | MMC_CAP_3_3V_DDR;
>
>         ret = mmc_of_parse(mmc);
> --
> 2.20.1
>