Re: [PATCH v2 3/4] ddr: imx: Allow to call ddr init without logging failure

On 8/26/26 10:12 AM, Frieder Schrempf wrote:

[...]

>>> I'm not sure, but even if it would work, it would require several
>>> separate init attempts only to read the IDs
>>
>> Why ? Init the bus in slowest mode with widest bus settings, then try
>> MRRD on all available DRAM chips, then figure out which ones report
>> valid IDs and which ones fail the MRd .
> 
> As far as I can see this doesn't work. If we use the widest bus setting
> (CsPresent=0x3) on a single rank module, the training fails and the DDR
> remains in a state where the MR read doesn't work yet.

Do you need training to read the IDs ? Simply force-use the slowest bus 
mode (100 MTps iirc), the training is only relevant for the high-speed 
modes.

[...]