Re: [PATCH] mmc: sdhci-pci: Only do AMD tuning for HS200

From: Ulf Hansson
Date: Wed Apr 11 2018 - 10:53:06 EST


On 7 April 2018 at 00:07, Daniel Kurtz <djkurtz@xxxxxxxxxxxx> wrote:
> Commit c31165d7400b ("mmc: sdhci-pci: Add support for HS200 tuning mode
> on AMD, eMMC-4.5.1") added a HS200 tuning method for use with AMD SDHCI
> controllers. As described in the commit subject, this tuning is specific
> for HS200. However, as implemented, this method is used for all host
> timings, because platform_execute_tuning, if it exists, is called
> unconditionally by sdhci_execute_tuning(). This breaks tuning when using
> the AMD controller with, for example, a DDR50 SD card.
>
> Instead, we can implement an amd execute_tuning wrapper callback, and
> then conditionally do the HS200 specific tuning for HS200, and otherwise
> call back to the standard sdhci_execute_tuning().
>
> Signed-off-by: Daniel Kurtz <djkurtz@xxxxxxxxxxxx>

Thanks, applied for fixes!

Added a fixes tag and stable tag.

Kind regards
Uffe

> ---
> drivers/mmc/host/sdhci-pci-core.c | 25 +++++++++++++++++++++++--
> 1 file changed, 23 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/mmc/host/sdhci-pci-core.c b/drivers/mmc/host/sdhci-pci-core.c
> index 787434e5589d..78c25ad35fd2 100644
> --- a/drivers/mmc/host/sdhci-pci-core.c
> +++ b/drivers/mmc/host/sdhci-pci-core.c
> @@ -1312,7 +1312,7 @@ static void amd_enable_manual_tuning(struct pci_dev *pdev)
> pci_write_config_dword(pdev, AMD_SD_MISC_CONTROL, val);
> }
>
> -static int amd_execute_tuning(struct sdhci_host *host, u32 opcode)
> +static int amd_execute_tuning_hs200(struct sdhci_host *host, u32 opcode)
> {
> struct sdhci_pci_slot *slot = sdhci_priv(host);
> struct pci_dev *pdev = slot->chip->pdev;
> @@ -1351,6 +1351,27 @@ static int amd_execute_tuning(struct sdhci_host *host, u32 opcode)
> return 0;
> }
>
> +static int amd_execute_tuning(struct mmc_host *mmc, u32 opcode)
> +{
> + struct sdhci_host *host = mmc_priv(mmc);
> +
> + /* AMD requires custom HS200 tuning */
> + if (host->timing == MMC_TIMING_MMC_HS200)
> + return amd_execute_tuning_hs200(host, opcode);
> +
> + /* Otherwise perform standard SDHCI tuning */
> + return sdhci_execute_tuning(mmc, opcode);
> +}
> +
> +static int amd_probe_slot(struct sdhci_pci_slot *slot)
> +{
> + struct mmc_host_ops *ops = &slot->host->mmc_host_ops;
> +
> + ops->execute_tuning = amd_execute_tuning;
> +
> + return 0;
> +}
> +
> static int amd_probe(struct sdhci_pci_chip *chip)
> {
> struct pci_dev *smbus_dev;
> @@ -1385,12 +1406,12 @@ static const struct sdhci_ops amd_sdhci_pci_ops = {
> .set_bus_width = sdhci_set_bus_width,
> .reset = sdhci_reset,
> .set_uhs_signaling = sdhci_set_uhs_signaling,
> - .platform_execute_tuning = amd_execute_tuning,
> };
>
> static const struct sdhci_pci_fixes sdhci_amd = {
> .probe = amd_probe,
> .ops = &amd_sdhci_pci_ops,
> + .probe_slot = amd_probe_slot,
> };
>
> static const struct pci_device_id pci_ids[] = {
> --
> 2.17.0.484.g0c8726318c-goog
>