Re: [PATCH 1/2] mmc: sdhci: Add Quirk for enabling HISPD under special conditions

From: Faiz Abbas
Date: Mon Apr 01 2019 - 05:02:11 EST


Hi Adrian,

On 01/04/19 2:21 PM, Adrian Hunter wrote:
> On 29/03/19 4:22 PM, Faiz Abbas wrote:
>> Some controllers on TI devices requires the HISPD bit to be cleared
>> even in some high speed modes. Add a quirk that facilitates this
>> requirement.
>
> Could you use sdhci I/O accessors for this?

Can you elaborate? Not sure how this would be solved with
CONFIG_MMC_SDHCI_IO_ACCESSORS.

Thanks,
Faiz

>
>>
>> Signed-off-by: Faiz Abbas <faiz_abbas@xxxxxx>
>> ---
>> drivers/mmc/host/sdhci.c | 36 ++++++++++++++++++++++++------------
>> drivers/mmc/host/sdhci.h | 2 ++
>> 2 files changed, 26 insertions(+), 12 deletions(-)
>>
>> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
>> index a8141ff9be03..ed4ed6054ddf 100644
>> --- a/drivers/mmc/host/sdhci.c
>> +++ b/drivers/mmc/host/sdhci.c
>> @@ -1916,18 +1916,30 @@ void sdhci_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
>> ctrl = sdhci_readb(host, SDHCI_HOST_CONTROL);
>>
>> if (!(host->quirks & SDHCI_QUIRK_NO_HISPD_BIT)) {
>> - if (ios->timing == MMC_TIMING_SD_HS ||
>> - ios->timing == MMC_TIMING_MMC_HS ||
>> - ios->timing == MMC_TIMING_MMC_HS400 ||
>> - ios->timing == MMC_TIMING_MMC_HS200 ||
>> - ios->timing == MMC_TIMING_MMC_DDR52 ||
>> - ios->timing == MMC_TIMING_UHS_SDR50 ||
>> - ios->timing == MMC_TIMING_UHS_SDR104 ||
>> - ios->timing == MMC_TIMING_UHS_DDR50 ||
>> - ios->timing == MMC_TIMING_UHS_SDR25)
>> - ctrl |= SDHCI_CTRL_HISPD;
>> - else
>> - ctrl &= ~SDHCI_CTRL_HISPD;
>> + if ((host->quirks2 & SDHCI_QUIRK2_TI_HISPD_BIT)) {
>> + if (ios->timing == MMC_TIMING_MMC_HS400 ||
>> + ios->timing == MMC_TIMING_MMC_HS200 ||
>> + ios->timing == MMC_TIMING_MMC_DDR52 ||
>> + ios->timing == MMC_TIMING_UHS_SDR50 ||
>> + ios->timing == MMC_TIMING_UHS_SDR104 ||
>> + ios->timing == MMC_TIMING_UHS_DDR50)
>> + ctrl |= SDHCI_CTRL_HISPD;
>> + else
>> + ctrl &= ~SDHCI_CTRL_HISPD;
>> + } else {
>> + if (ios->timing == MMC_TIMING_SD_HS ||
>> + ios->timing == MMC_TIMING_MMC_HS ||
>> + ios->timing == MMC_TIMING_MMC_HS400 ||
>> + ios->timing == MMC_TIMING_MMC_HS200 ||
>> + ios->timing == MMC_TIMING_MMC_DDR52 ||
>> + ios->timing == MMC_TIMING_UHS_SDR50 ||
>> + ios->timing == MMC_TIMING_UHS_SDR104 ||
>> + ios->timing == MMC_TIMING_UHS_DDR50 ||
>> + ios->timing == MMC_TIMING_UHS_SDR25)
>> + ctrl |= SDHCI_CTRL_HISPD;
>> + else
>> + ctrl &= ~SDHCI_CTRL_HISPD;
>> + }
>> }
>>
>> if (host->version >= SDHCI_SPEC_300) {
>> diff --git a/drivers/mmc/host/sdhci.h b/drivers/mmc/host/sdhci.h
>> index 01002cba1359..aac026c5e184 100644
>> --- a/drivers/mmc/host/sdhci.h
>> +++ b/drivers/mmc/host/sdhci.h
>> @@ -485,6 +485,8 @@ struct sdhci_host {
>> * block count.
>> */
>> #define SDHCI_QUIRK2_USE_32BIT_BLK_CNT (1<<18)
>> +/* Some TI devices need the high speed bit disabled even in high speed modes */
>> +#define SDHCI_QUIRK2_TI_HISPD_BIT (1<<19)
>>
>> int irq; /* Device IRQ */
>> void __iomem *ioaddr; /* Mapped address */
>>
>