FSL/NXP P5020: USB problems with the latest Git kernels

[Darren Stevens]

Hello Scott

On 27/08/2018, Scott Wood wrote:
> On Mon, 2018-08-27 at 20:15 +0200, Christian Zigotzky wrote:
>> Hello,
>> 
>> Our users tested the RC1 of kernel 4.19 on their P5020 boards today.
>> Unfortunately the USB bug still exists. With mem values bigger than 4096M,
>> the USB mouse and keyboard doesn't work. With the bootarg mem=4096M, the USB
>> devices work without any problems. Please compile the RC1 and test it on
>> your P5020 board. There is a problem with the memory management since
>> 22/08/18. 
>
> I just tested 4.19-rc1 on a T4240 and got a similar problem with MMC.  MMC and
> USB on these chips both have a 32-bit DMA limitation.  I'll look into it.

I've run a bisect locally on my system and found the following bad commit:

# first bad commit: [1b1eeca7e4c19fa76d409d4c7b338dba21f2df45] init: allow initcall tables to be emitted using relative references

I can't see why this would fail though, and it only seems to affect fsl machines, and on mine it killed the onboard sata as well.

Hope this helps.

Regards
Darren