[U-Boot] [U-Boot, BUG] snow: mmc: SD card access broken: unable to select a mode

[Guillaume Gardet]

Hi,

Le 16/05/2018 à 09:22, Guillaume Gardet a écrit :
> Hi Jaehoon,
>
>
> Le 26/04/2018 à 15:15, Guillaume Gardet a écrit :
>>
>>
>> Le 26/04/2018 à 12:31, Jaehoon Chung a écrit :
>>> Hi,
>>>
>>> On 04/09/2018 09:02 PM, Guillaume Gardet wrote:
>>>> Hi Jaehoon,
>>>>
>>>> There are problems with SD card access on Samsung Chromebook (snow) with latest master (and also 2018.05-rc1 and 2018.03).
>>>>
>>>> eMMC is ok, but SD card access leads to 'unable to select a mode' problem. If I disable HS mode, I can access the SD card without problem:
>>>> ********************************************************************************
>>>> ********************************************************************************
>>>>
>>>> Once we try to select HS mode, all access to SD card result in failure, even when trying to setup a lower frequency mode, including SD legacy at 25 MHz.
>>>>
>>>> Any idea what is going? Maybe you have fixes pending?
>>> Sorry for late. Hmm. I will check your issue. Just disable MMC_MODE_HS, then it's working fine?
>>> or HS_52MHz?
>>
>> I tried to disable HS_52MHz only and it did not fix the problem. Then I tried to disable both HS and HS_52MHz and it fixed the problem.
>
> Any progress on this problem?


Ping again.
The problem is still there in u-boot v2018.11-rc1.


Guillaume


>
> Guillaume
>
>>
>>
>> Guillaume
>>
>>>
>>> Best Regards,
>>> Jaehoon Chung
>>>
>>>>
>>>> Guillaume
>>>>
>>>> diff --git a/drivers/mmc/dw_mmc.c b/drivers/mmc/dw_mmc.c
>>>> index 23f642980bf..28f4fa0f213 100644
>>>> --- a/drivers/mmc/dw_mmc.c
>>>> +++ b/drivers/mmc/dw_mmc.c
>>>> @@ -508,7 +508,8 @@ void dwmci_setup_cfg(struct mmc_config *cfg, struct dwmci_host *host,
>>>>            cfg->host_caps |= MMC_MODE_4BIT;
>>>>            cfg->host_caps &= ~MMC_MODE_8BIT;
>>>>        }
>>>> -    cfg->host_caps |= MMC_MODE_HS | MMC_MODE_HS_52MHz;
>>>> +    /* Temp workaround for Chromebook snow to avoid the 'unable to select a mode' error */
>>>> +//     cfg->host_caps |= MMC_MODE_HS | MMC_MODE_HS_52MHz;
>>>>
>>>>        cfg->b_max = CONFIG_SYS_MMC_MAX_BLK_COUNT;
>>>>    }
>>>>
>>>
>>
>