[U-Boot] [PATCH] ts4800: add CONFIG_SYS_FSL_ERRATUM_ESDHC_A001

[Sebastien Bourdelin <sebastien.bourdelin@savoirfairelinux.com>]

Hi,

On 04/21/2016 05:39 PM, Sebastien Bourdelin wrote:
> Hi,
> I add Fabio Estevam in the loop as suggested by Marek Vasut on IRC.
>
> On 04/21/2016 01:37 PM, Sebastien Bourdelin wrote:
>> This commit fixes the MMC data transactions timeout problem on the
>> TS4800.
>>
>> The changes introduced in the commit e978a31 on the timeout calculation
>> for the MMC data transactions has revealed there is something wrong with
>> the timeout setting of the eSDHC controller used in the IMX51.
>>
>> The IMX51 seems to be concerned by this erratum and without this change
>> the MMC driver is unable to do any transactions.
>>
>> Signed-off-by: Sebastien Bourdelin <sebastien.bourdelin@savoirfairelinux.com>
>> ---
>>  include/configs/ts4800.h | 2 ++
>>  1 file changed, 2 insertions(+)
>>
>> diff --git a/include/configs/ts4800.h b/include/configs/ts4800.h
>> index fcc9d80..5e5e4d3 100644
>> --- a/include/configs/ts4800.h
>> +++ b/include/configs/ts4800.h
>> @@ -63,6 +63,8 @@
>>  #define CONFIG_FSL_ESDHC
>>  #define CONFIG_SYS_FSL_ESDHC_ADDR	MMC_SDHC1_BASE_ADDR
>>  
>> +#define CONFIG_SYS_FSL_ERRATUM_ESDHC_A001
>> +
>>  #define CONFIG_MMC
>>  
>>  #define CONFIG_CMD_MMC
> The problem we found is related to the DTOCV field in the system control
> register of the IMX51's eSDHC controller.  If we set the value 4, 8 or
> 12 in this DTOCV field the MMC driver is unable to do any data
> transactions, we have a timeout (i.e: the DTOE field in the Interrupt
> status register of the eSDHC controller is set to 1).
> It works with other values, at least i tried with 5, 9, 11, 13 without
> having any timeout.
>
> Our guess and because we didn't find any errata related to this issue
> for the IMX51 is that this device is impacted by the same problem then
> devices MPC83XX and MPC85XX (see the ESDHC-A001 errata in the datasheet:
> http://pdf.datasheetarchive.com/indexerfiles/Datasheets-SW1/DSASW0012367.pdf)
>
> Perhaps someone from Freescale can give us more informations.
>
> Regards,
> Sebastien.

Did someone from Freescale had the time to take a look at this patch and can
give us more information?
We still need it to boot the TS4800.

Regards,
Sebastien.