[PATCH v3 2/2] mmc: tegra: fix reporting of base clock frequency

Ulf Hansson ulf.hansson at linaro.org
Fri May 23 00:04:12 PDT 2014


On 22 May 2014 17:55, Andrew Bresticker <abrestic at chromium.org> wrote:
> Tegra SDHCI controllers, by default, report a base clock frequency
> of 208Mhz in SDHCI_CAPABILTIES which may or may not be equal to the
> actual base clock frequency.  This is because the clock rate is
> configured by the clock controller, which is external to the SD/MMC
> controller.  Since the SD/MMC controller has no knowledge of how this
> clock is configured, it will simply report the maximum frequency.
> While the reported value can be overridden by setting BASE_CLK_FREQ in
> VENDOR_CLOCK_CTRL on Tegra30 and later SoCs, just set CAP_CLOCK_BASE_BROKEN
> and supply sdhci_pltfm_clk_get_max_clock(), which simply does a
> clk_get_rate(), as the get_max_clock() callback.
>
> Signed-off-by: Andrew Bresticker <abrestic at chromium.org>
> Tested-by: Stephen Warren <swarren at nvidia.com>
> Acked-by: Stephen Warren <swarren at nvidia.com>

Thanks Andrew!

Signed-off-by: Ulf Hansson <ulf.hansson at linaro.org>

Chris, can you pick this up?

Kind regards
Ulf Hansson

> ---
> Changes from v2:
>  - rebased on mmc-next
> Changes from v1:
>  - fixed up commit message per Stephen's suggestions
> ---
>  drivers/mmc/host/sdhci-tegra.c | 10 +++++++---
>  1 file changed, 7 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci-tegra.c b/drivers/mmc/host/sdhci-tegra.c
> index 4375cd4..d93a063 100644
> --- a/drivers/mmc/host/sdhci-tegra.c
> +++ b/drivers/mmc/host/sdhci-tegra.c
> @@ -154,13 +154,15 @@ static const struct sdhci_ops tegra_sdhci_ops = {
>         .set_bus_width = tegra_sdhci_set_bus_width,
>         .reset      = tegra_sdhci_reset,
>         .set_uhs_signaling = sdhci_set_uhs_signaling,
> +       .get_max_clock = sdhci_pltfm_clk_get_max_clock,
>  };
>
>  static const struct sdhci_pltfm_data sdhci_tegra20_pdata = {
>         .quirks = SDHCI_QUIRK_BROKEN_TIMEOUT_VAL |
>                   SDHCI_QUIRK_SINGLE_POWER_WRITE |
>                   SDHCI_QUIRK_NO_HISPD_BIT |
> -                 SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC,
> +                 SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
> +                 SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
>         .ops  = &tegra_sdhci_ops,
>  };
>
> @@ -175,7 +177,8 @@ static const struct sdhci_pltfm_data sdhci_tegra30_pdata = {
>                   SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
>                   SDHCI_QUIRK_SINGLE_POWER_WRITE |
>                   SDHCI_QUIRK_NO_HISPD_BIT |
> -                 SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC,
> +                 SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
> +                 SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
>         .ops  = &tegra_sdhci_ops,
>  };
>
> @@ -191,7 +194,8 @@ static const struct sdhci_pltfm_data sdhci_tegra114_pdata = {
>                   SDHCI_QUIRK_DATA_TIMEOUT_USES_SDCLK |
>                   SDHCI_QUIRK_SINGLE_POWER_WRITE |
>                   SDHCI_QUIRK_NO_HISPD_BIT |
> -                 SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC,
> +                 SDHCI_QUIRK_BROKEN_ADMA_ZEROLEN_DESC |
> +                 SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN,
>         .ops  = &tegra_sdhci_ops,
>  };
>
> --
> 1.9.1.423.g4596e3a
>



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