Re: [PATCH] crypto: caam: map job ring registers without claiming region

[Emanuele Ghidoli <ghidoliemanuele@gmail.com>]

On 9/2/26 08:10, Francesco Dolcini wrote:
> + Emanuele
> 
> On Tue, Sep 01, 2026 at 01:37:36PM -0700, Rosen Penev wrote:
>> devm_platform_ioremap_resource() ends up calling request_mem_region(),
>> which fails with -EBUSY on i.MX SoCs:
>>
>> There the job rings are modelled as sub-regions of their parent
>> fsl,sec-v4.0 register window, and caam_probe() already reserves the
>> whole window exclusively via devm_of_iomap() before the children are
>> populated.  Every job ring therefore collides with its own parent and
>> fails to probe, taking the hardware RNG offline (seen on i.MX6, i.MX7
>> and i.MX8 boards such as colibri-imx7 and verdin-imx8mp).
>>
>> Map the job ring registers with devm_ioremap() instead, which does not
>> claim the (already owned) region.
>>
>> Fixes: 9a955c0a7d11 ("crypto: caam - simplify probe resource and IRQ handling")
>> Assisted-by: opencode:big-pickle
>> Signed-off-by: Rosen Penev <rosenp@gmail.com>
> 
> Reported-by: Emanuele Ghidoli <ghidoliemanuele@gmail.com>
> Closes: https://lore.kernel.org/lkml/20260901194524.908240-1-ghidoliemanuele@gmail.com/
> 
> Thanks,
> Francesco

Tested on colibri-imx7.

Tested-by: Emanuele Ghidoli <emanuele.ghidoli@toradex.com>

Thanks,
Emanuele