Re: [PATCH v3 2/7] media: iris: switch to hardware mode after firmware boot

[Vikash Garodia]

On 3/13/2026 6:49 PM, Vikash Garodia wrote:
> Currently the driver switches the vcodec GDSC to hardware (HW) mode
> before firmware load and boot sequence. GDSC can be powered off, keeping
> in hw mode, thereby the vcodec registers programmed in TrustZone (TZ)
> carry default (reset) values.
> Move the transition to HW mode after firmware load and boot sequence.
>
> The bug was exposed with driver configuring different stream ids to
> different devices via iommu-map. With registers carrying reset values,
> VPU would not generate desired stream-id, thereby leading to SMMU fault.
>
> For vpu4, when GDSC is switched to HW mode, there is a need to perform
> the reset operation. Without reset, there are occassional issues of
> register corruption observed. Hence the vpu GDSC switch also involves
> the reset.
>
> Fixes: dde659d37036 ("media: iris: Introduce vpu ops for vpu4 with necessary hooks")
> Co-developed-by: Vishnu Reddy <busanna.reddy@xxxxxxxxxxxxxxxx>
> Signed-off-by: Vishnu Reddy <busanna.reddy@xxxxxxxxxxxxxxxx>
> Signed-off-by: Vikash Garodia <vikash.garodia@xxxxxxxxxxxxxxxx>
> ---

Hi Bryan,

Please pull this fix patch, let me know if you need me to resend this 
separately.

Regards,
Vikash