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

[Faiz Abbas <faiz_abbas@ti.com>]

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@ti.com>
>> ---
>>  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 */
>>
>