[PATCH v4 1/4] imx9: Add support for saving DDR training data to NVM

[Marek Vasut]

On 6/2/26 3:46 PM, Simona Toaca wrote:

Hi,

>>> +	ret = spi_flash_erase_dm(flash, offset, QB_STATE_LOAD_SIZE);
>> Can you please double-check whether "offset" here is always aligned to 64
>> kiB (SPI NOR erase block size) ? If not, this erase here will fail.
>>
>> Thank you
> 
> The erase size of the SPI NOR should actually be 4kiB.

That does not apply to all devices. I assume to align this data to 64 
kiB offset, I would need a replacement AHAB container?

> I added
> a patch a while back enabling SFDP support, so that the erase size is
> parsed correctly and this does not fail. I only enabled it on U-Boot,
> but if you are using SPL you should enable it there too.
> 
> The only reason why I did not enable it for SPL is that there seems
> to not be any defconfig for iMX95/943/952 for booting from SPI NOR.
> 
> Trying 'qb save spi' from eMMC on an iMX943 EVK (with SFDP enabled):
> u-boot=> qb save spi
> SF: Detected mt35xu512aba with page size 256 Bytes, erase size 4 KiB,
> total 64 MiB
> u-boot=> echo $?
> 0
> 
> Without SFDP, 'sf probe' reports 128kiB erase size, not 64kiB.
> 
> I also do not see why I would check if the offset is a multiple of
> the erase size, since the erase fails gracefully.
My understanding is, that the erase operation should erase the QB data 
from the SPI NOR, not ignore failure and keep the data there ?