Re: [PATCH v5] dma: qcom: bam_dma: Fix command element mask field for BAM v1.6.0+

[Md Sadre Alam]

Hi,

On 6/4/2026 4:15 PM, Varadarajan Narayanan wrote:
> On Tue, May 19, 2026 at 11:01:51PM +0530, Vinod Koul wrote:
> > On 14-05-26, 12:09, Varadarajan Narayanan wrote:
> > > From: Md Sadre Alam <md.alam@xxxxxxxxxxxxxxxx>
> > >
> > > BAM version 1.6.0 and later changed the behavior of the mask field in
> > > command elements for read operations. In newer BAM versions, the mask
> > > field for read commands contains the upper 4 bits of the destination
> > > address to support 36-bit addressing, while for write commands it
> > > continues to function as a traditional write mask.
> >
> > But this changes behaviour for all versions. What happens to folks on older
> > versions, wont this break for them, if not what am I missing

It will not have any impact on older version of BAM controller. Konrad 
also had a similar concern. Please refer to [1]

[1] 
https://lore.kernel.org/linux-arm-msm/2394e63f-1df7-764e-5489-3567065707a1@xxxxxxxxxxx/

Thanks,
Alam.