Re: [edk2-devel] [PATCH v3 6/7] Platform/RaspberryPi: Power up sd, and tweak GPIOs

["Jeremy Linton" <jeremy.linton@arm.com>]

Hi,

On 1/4/21 12:44 PM, Philippe Mathieu-Daudé wrote:
> On 1/4/21 6:37 PM, Jeremy Linton wrote:
>> It seems we should be powering up the sd cards, and possibly
>> the clocks as well to assure they are setup properly before
>> we attempt to access the controller.
>>
>> Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
>> Reviewed-by: Andrei Warkentin <awarkentin@vmware.com>
>> ---
>>   Platform/RaspberryPi/Drivers/ConfigDxe/ConfigDxe.c | 10 ++++++++++
>>   1 file changed, 10 insertions(+)
>>
>> diff --git a/Platform/RaspberryPi/Drivers/ConfigDxe/ConfigDxe.c b/Platform/RaspberryPi/Drivers/ConfigDxe/ConfigDxe.c
>> index 28f57438c5..e55ed63efa 100644
>> --- a/Platform/RaspberryPi/Drivers/ConfigDxe/ConfigDxe.c
>> +++ b/Platform/RaspberryPi/Drivers/ConfigDxe/ConfigDxe.c
>> @@ -552,6 +552,16 @@ ApplyVariables (
>>         GpioPinFuncSet (37, GPIO_FSEL_ALT3);
>>         GpioPinFuncSet (38, GPIO_FSEL_ALT3);
>>         GpioPinFuncSet (39, GPIO_FSEL_ALT3);
>> +
>> +      /*
>> +       * power and clock everything by default
> 
> Isn't this comment a bit exaggerated? You only power the minimum
> required to use the SD controller to access the card.

Maybe. Since I will be re-posting, maybe just dropping the comment is 
reasonable since the code is fairly self explanatory now.


> 
>> +       */
>> +      Status = mFwProtocol->SetPowerState (RPI_MBOX_POWER_STATE_SDHCI,
>> +                                           TRUE, TRUE); //SD on with wait
>> +      Status = mFwProtocol->SetGpioConfig (RPI_EXP_GPIO_SD_VOLT,
>> +                                           RPI_EXP_GPIO_DIR_OUT, TRUE); //3.3v
>> +      Status = mFwProtocol->SetClockState (RPI_MBOX_CLOCK_RATE_EMMC2, TRUE);
>> +      Status = mFwProtocol->SetClockState (RPI_MBOX_CLOCK_RATE_EMMC, TRUE);
>>       }
>>     } else {
>>       DEBUG ((DEBUG_ERROR, "Model Family %d not supported...\n", mModelFamily));
>>
>