Hi Adrian,

On Tuesday 15 August 2017 12:57 PM, Adrian Hunter wrote:
> On 07/08/17 19:01, Kishon Vijay Abraham I wrote:
>> TI's implementation of sdhci controller used in DRA7 SoC's doesn't
>> strip CRC in responses with length 136 bits. Add quirk to indicate
>> the controller does not strip CRC in MMC_RSP_136. If this quirk is
>> set sdhci library shouldn't shift the response present in
>> SDHCI_RESPONSE register.
>>
>> Signed-off-by: Kishon Vijay Abraham I <kis...@ti.com>
>> ---
>>  drivers/mmc/host/sdhci.c | 27 +++++++++++++++++++--------
>>  drivers/mmc/host/sdhci.h |  2 ++
>>  2 files changed, 21 insertions(+), 8 deletions(-)
>>
>> diff --git a/drivers/mmc/host/sdhci.c b/drivers/mmc/host/sdhci.c
>> index ecd0d4350e8a..ece3751d2a25 100644
>> --- a/drivers/mmc/host/sdhci.c
>> +++ b/drivers/mmc/host/sdhci.c
>> @@ -1182,14 +1182,25 @@ static void sdhci_finish_command(struct sdhci_host 
>> *host)
>>  
>>      if (cmd->flags & MMC_RSP_PRESENT) {
>>              if (cmd->flags & MMC_RSP_136) {
>> -                    /* CRC is stripped so we need to do some shifting. */
>> -                    for (i = 0;i < 4;i++) {
>> -                            cmd->resp[i] = sdhci_readl(host,
>> -                                    SDHCI_RESPONSE + (3-i)*4) << 8;
>> -                            if (i != 3)
>> -                                    cmd->resp[i] |=
>> -                                            sdhci_readb(host,
>> -                                            SDHCI_RESPONSE + (3-i)*4-1);
>> +                    if (!(host->quirks2 & SDHCI_QUIRK2_NO_CRC_STRIPPING)) {
> 
> This is about the 136-bit response so let's put that in the quirk name.  How 
> about SDHCI_QUIRK2_RSP_136_HAS_CRC

Since omap seems to be the only platform that doesn't have CRC, I prefer adding
SDHCI_QUIRK2_RSP_136_NO_CRC. That way we can add the quirk only in sdhci-omap
instead of all the existing sdhci drivers.

> 
>> +                            /*
>> +                             * CRC is stripped so we need to do some
>> +                             * shifting.
>> +                             */
>> +                            for (i = 0; i < 4; i++) {
>> +                                    cmd->resp[i] =
>> +                                            sdhci_readl(host, SDHCI_RESPONSE
>> +                                                        + (3 - i) * 4) << 8;
>> +                                    if (i != 3)
>> +                                            cmd->resp[i] |=
>> +                                            sdhci_readb(host, SDHCI_RESPONSE
>> +                                                        + (3 - i) * 4 - 1);
>> +                            }
>> +                    } else {
>> +                            for (i = 0; i < 4; i++)
>> +                                    cmd->resp[i] =
>> +                                    sdhci_readl(host, SDHCI_RESPONSE +
>> +                                                (3 - i) * 4);
>>                      }
> 
> This is all very jammed up against the 80 column margin.  Please make a new 
> patch to separate it into a new function sdhci_read_rsp_136() and then 
> another patch to add the quirk.
> i.e. completely untested!

Sure. Thanks for the patch.

Thanks
Kishon

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