Re: [PATCH] dmaengine: qcom: bam_dma: Avoid accessing BAM_REVISION on remote BAM

[Georgi Djakov]

On 7.02.25 22:17, Bjorn Andersson wrote:
> Commit '57a7138d0627 ("dmaengine: qcom: bam_dma: Avoid writing
> unavailable register")' made this read unconditional, in order to
> identify if the instance is BAM-NDP or BAM-Lite.
> But the BAM_REVISION register is not accessible on remotely managed BAM
> instances and attempts to access it causes the system to crash.
>
> Move the access back to be conditional and expand the checks that was
> introduced to restore the old behavior when no revision information is
> available.
>
> Fixes: 57a7138d0627 ("dmaengine: qcom: bam_dma: Avoid writing unavailable register")
> Reported-by: Georgi Djakov <djakov@xxxxxxxxxx>
> Closes: https://lore.kernel.org/lkml/9ef3daa8-cdb1-49f2-8d19-a72d6210ff3a@xxxxxxxxxx/
> Signed-off-by: Bjorn Andersson <bjorn.andersson@xxxxxxxxxxxxxxxx>

Tested-by: Georgi Djakov <djakov@xxxxxxxxxx> # db845c

Thanks,
Georgi