Re: Regression: memory corruption on Atmel SAMA5D31

From: Tudor.Ambarus
Date: Thu Jul 28 2022 - 03:45:34 EST


On 7/13/22 19:01, Tudor.Ambarus@xxxxxxxxxxxxx wrote:
> EXTERNAL EMAIL: Do not click links or open attachments unless you know the content is safe
>
> Hi, Peter,
>
> Thanks for the patience. I was still out of office last week,
> but now I have some news.
>
> On 6/27/22 19:53, Tudor.Ambarus@xxxxxxxxxxxxx wrote:
>> I think these are the last less invasive
>> changes that I try, I'll have to rewrite the logic anyway.
>
> I've chopped the driver to use virt-dma (check [1]). It's not clean, but
> it works and one can see how the logic is changed. Unfortunately the mem
> corruption is still present on high loads. Maybe it's a coherency problem.
> I need more time on it. Will get back to you.
>
> Cheers,
> ta
>
> [1] To github.com:ambarus/linux-0day.git
> a7351e6f4c12..1557e0df0fd0 at-hdmac-virt-dma -> at-hdmac-virt-dma

Hi, Peter,

Does this [1] one line patch solve the mem corruption on your side?
Even if yes, there are still bugs in at-hdmac that can be squashed by
using virt-dma. I'd like to follow up with patches that integrate
virt-dma logic in at-hdmac.

Cheers,
ta

[1] https://lore.kernel.org/linux-mtd/20220728074014.145406-1-tudor.ambarus@xxxxxxxxxxxxx/T/#u