Re: [PATCH] [RFC] spi: cadence-quadspi: Disable DAC on SoCFPGA

[Dinh Nguyen <dinguyen@kernel.org>]

On 2/21/22 11:05, Marek Vasut wrote:
> On 2/21/22 17:38, Dinh Nguyen wrote:
>>
>>
>> On 2/20/22 22:32, Marek Vasut wrote:
>>> On SoCFPGA Gen5, DAC memcpy_fromio() in cqspi_direct_read_execute()
>>> leads to data abort, disable DAC to avoid triggering it:
>>>
>>> Unhandled fault: imprecise external abort (0x1406) at 0x0400d3e9
>>> [0400d3e9] *pgd=00000000
>>>
>>> Signed-off-by: Marek Vasut <marex@denx.de>
>>> Cc: Dinh Nguyen <dinguyen@kernel.org>
>>> Cc: Pratyush Yadav <p.yadav@ti.com>
>>> ---
>>>   drivers/spi/spi-cadence-quadspi.c | 2 +-
>>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/spi/spi-cadence-quadspi.c 
>>> b/drivers/spi/spi-cadence-quadspi.c
>>> index b808c94641fa6..65f2c2449be09 100644
>>> --- a/drivers/spi/spi-cadence-quadspi.c
>>> +++ b/drivers/spi/spi-cadence-quadspi.c
>>> @@ -1870,7 +1870,7 @@ static const struct cqspi_driver_platdata 
>>> intel_lgm_qspi = {
>>>   };
>>>   static const struct cqspi_driver_platdata socfpga_qspi = {
>>> -    .quirks = CQSPI_NO_SUPPORT_WR_COMPLETION,
>>> +    .quirks = CQSPI_DISABLE_DAC_MODE | CQSPI_NO_SUPPORT_WR_COMPLETION,
>>>   };
>>>   static const struct cqspi_driver_platdata versal_ospi = {
>>
>> Acked-by: Dinh Nguyen <dinguyen@kernel.org>
> 
> Is this DAC really not working on socfpga gen5 or is there some other 
> issue ?

I don't know the answer to this question. What is the DAC in the QSPI 
module and how do I go about testing it?

Dinh