Re: [PATCH v5 12/14] media: iris: Add platform data for glymur

[Dmitry Baryshkov]

On Mon, May 11, 2026 at 09:45:01PM +0530, Vishnu Reddy wrote:
> 
> On 5/9/2026 2:35 AM, Dmitry Baryshkov wrote:
> > On Sat, May 09, 2026 at 12:30:01AM +0530, Vishnu Reddy wrote:
> >> On glymur platform, the iris core shares most properties with the
> >> iris core on the SM8550 platform. The major difference is that glymur
> >> integrates two codec cores (vcodec0 and vcodec1), while SM8550 has only
> >> one. Add glymur specific platform data, reusing SM8550 definitions
> >> wherever applicable.
> > This leave me in confusion. Having two cores, each with its own set of
> > clocks and pm domains, I'd have expected that each core scales
> > independently. I.e. if the load is pushed to the core0, it requires
> > core0 clocks to go higher (while core1 clocks can stay at the low freq).
> > Or, at least, the clocks would be set to the frequency corresponding to
> > the max of the workloads (if for some reason the cores should stay in
> > sync).
> >
> > However, I don't see it in the code. All clocks and all power domains
> > seem do be scaled using the common workload. If my assumptions were not
> > correct, please explain it in the commit message.
> 
> The OPP core logic sets the rpmhpd level and clock rate based on the OPP table
> defined in the DT node, where the clock frequency and power rail level are
> tightly coupled together. Since vcodec0 and vcodec1 share the same power rails,
> independently scaling one clock high while keeping the other low is not
> straightforward within this OPP framework.
> 
> Do you have any suggestion on how best to handle per core independent clock
> scaling within these constraints?

This would require more plumbing and driver changes, but:

	iris: video-codec@foo {
		compatible = "qcom,glymur-iris",
		clocks = <only-core-clocks>;
		resets = <only-core-resets>;

		/* or core@0 */
		codec@0 {
			clocks, resets, power-domains;
			operating-points-v2 = <&iris_opp_table>
		};

		/* or core@1 */
		codec@1 {
			clocks, resets, power-domains;
			operating-points-v2 = <&iris_opp_table>
		};

		iris_opp_table: opp-table {
			compatible = "operating-points-v2"
		};
	};

> 
> >> Reviewed-by: Vikash Garodia <vikash.garodia@xxxxxxxxxxxxxxxx>
> >> Signed-off-by: Vishnu Reddy <busanna.reddy@xxxxxxxxxxxxxxxx>
> >> ---
> >>  drivers/media/platform/qcom/iris/Makefile          |  1 +
> >>  .../platform/qcom/iris/iris_platform_common.h      |  5 ++
> >>  .../media/platform/qcom/iris/iris_platform_gen2.c  | 99 ++++++++++++++++++++++
> >>  .../platform/qcom/iris/iris_platform_glymur.c      | 97 +++++++++++++++++++++
> >>  .../platform/qcom/iris/iris_platform_glymur.h      | 17 ++++
> >>  drivers/media/platform/qcom/iris/iris_probe.c      |  4 +
> >>  6 files changed, 223 insertions(+)
> >>

-- 
With best wishes
Dmitry