[PATCH 1/6] Revert "spi: zynq_qspi: Add parallel memories support in QSPI driver"

[Marek Vasut]

On 10/23/24 10:17 AM, Michal Simek wrote:
> 
> 
> On 10/22/24 23:06, Marek Vasut wrote:
>> This reverts commit 1e36d34b52e7a1ebe5a2a5339d6905540f4253aa.
>>
>> This parallel/stacked support breaks basic SPI NOR support,
>> e.g. this no longer works:
>>
>> => sf probe && sf update 0x50000000 0 0x160000
>> SF: Detected s25fs512s with page size 256 Bytes, erase size 256 KiB, 
>> total 64 MiB
>> device 0 offset 0x0, size 0x160000
>> SPI flash failed in read step
> 
> Reverting everything seems to me too much. Tom has tested it on his HW 
> and didn't see any issue. That's why better to look at code which is 
> causing this.
> You are reverting everything but likely there is specific patch which is 
> causing this. Which one is it?
> Which board was used for your testing? Likely we don't have access to it.
> Is there any QEMU available which can be used for debugging?

The testcase including the exact SPI NOR model is above.

iMX6 with w25q16dw seems to be broken too.

Basically every board I have access no longer has a working "sf probe ; 
sf update" combination ... so yeah, this means this patchset is 
fundamentally broken.

>> Since none of this seems to be in Linux either, revert it all.
> 
> This has been discussed with Tom before.

Tom is not the U-Boot MTD maintainer ?

> It wasn't in sync even before 
> and we can't really stop development on subsystems.
These patches have been rejected from mainline Linux for many years, why 
are they added to U-Boot which includes an import of MTD subsystem from 
Linux ? Such diverging code base with random patches will only make it 
much harder to synchronize Linux MTD subsystem back to U-Boot.