Re: [PATCH v2 07/12] media: iris: Create pixel and non-pixel context banks on VPU3x

On Fri, Jul 31, 2026 at 11:52:22PM +0530, Vikash Garodia wrote:
> The VPU issues DMA through several SMMU streams, and the hardware does
> not give every stream the same addressable range. The non-pixel stream
> is restricted to use 0-600MB of IOVA space, while the pixel stream can
> address the full range.
> 
> Implement the context bank hooks for VPU3x. iris_vpu3x_init_cb_devs()
> creates the "non-pixel" and "pixel" devices from the matching device tree
> subnodes, and iris_vpu3x_deinit_cb_devs() unregisters them. If creating
> the pixel device fails, the non-pixel device is unregistered and its
> pointer cleared before the error is returned.
> 
> Wire the hooks into iris_vpu3_ops and iris_vpu33_ops, which cover the
> platforms whose device trees are converted to context bank subnodes.
> iris_vpu35_ops is left unchanged, as sm8750 still describes its streams
> with "iommus" on the parent node, and the fallback in iris_get_cb_dev()
> keeps it working until its device tree is converted.
> 
> Backports are intended since the first DTS of 8550 binding schema.
> 
> Fixes: 41661853ae8e ("arm64: dts: qcom: sm8550: add iris DT node")

Drop

> Cc: [email protected]
> Co-developed-by: Vishnu Reddy <[email protected]>
> Signed-off-by: Vishnu Reddy <[email protected]>
> Tested-by: Daniel J Blueman <[email protected]>
> Signed-off-by: Vikash Garodia <[email protected]>
> ---
>  drivers/media/platform/qcom/iris/iris_vpu3x.c | 38 +++++++++++++++++++++++++++
>  1 file changed, 38 insertions(+)
> 
> diff --git a/drivers/media/platform/qcom/iris/iris_vpu3x.c b/drivers/media/platform/qcom/iris/iris_vpu3x.c
> index 3dad47be78b58f6cd5ed6f333b3376571a04dbf0..623a0f8a7982c0b5c2e3741a34c1367e9aaf4e27 100644
> --- a/drivers/media/platform/qcom/iris/iris_vpu3x.c
> +++ b/drivers/media/platform/qcom/iris/iris_vpu3x.c
> @@ -254,6 +254,40 @@ static void iris_vpu35_power_off_hw(struct iris_core *core)
>  	iris_disable_unprepare_clock(core, IRIS_AXI_CLK);
>  }
>  
> +static int iris_vpu3x_init_cb_devs(struct iris_core *core)

What is 3x-specific in these functions? Can they go to vpu_common
instead, as they seem to be applicable to all generations. And also, if
they are common, do we really need callbacks? Can we just call these two
functions directly?

> +{
> +	struct device *dev;
> +
> +	dev = iris_create_cb_dev(core, "non-pixel");
> +	if (IS_ERR(dev))
> +		return PTR_ERR(dev);
> +
> +	core->np_dev = dev;
> +
> +	dev = iris_create_cb_dev(core, "pixel");
> +	if (IS_ERR(dev))
> +		goto unreg_np_dev;
> +
> +	core->p_dev = dev;
> +
> +	return 0;
> +
> +unreg_np_dev:
> +	if (core->np_dev)
> +		platform_device_unregister(to_platform_device(core->np_dev));
> +	core->np_dev = NULL;
> +
> +	return PTR_ERR(dev);
> +}
> +
> +static void iris_vpu3x_deinit_cb_devs(struct iris_core *core)
> +{
> +	if (core->p_dev)
> +		platform_device_unregister(to_platform_device(core->p_dev));
> +	if (core->np_dev)
> +		platform_device_unregister(to_platform_device(core->np_dev));
> +}
> +
>  const struct vpu_ops iris_vpu3_ops = {
>  	.power_off_hw = iris_vpu3_power_off_hardware,
>  	.power_on_hw = iris_vpu_power_on_hw,
> @@ -261,6 +295,8 @@ const struct vpu_ops iris_vpu3_ops = {
>  	.power_on_controller = iris_vpu_power_on_controller,
>  	.calc_freq = iris_vpu3x_vpu4x_calculate_frequency,
>  	.set_hwmode = iris_vpu_set_hwmode,
> +	.init_cb_devs = iris_vpu3x_init_cb_devs,
> +	.deinit_cb_devs = iris_vpu3x_deinit_cb_devs,
>  };
>  
>  const struct vpu_ops iris_vpu33_ops = {
> @@ -270,6 +306,8 @@ const struct vpu_ops iris_vpu33_ops = {
>  	.power_on_controller = iris_vpu_power_on_controller,
>  	.calc_freq = iris_vpu3x_vpu4x_calculate_frequency,
>  	.set_hwmode = iris_vpu_set_hwmode,
> +	.init_cb_devs = iris_vpu3x_init_cb_devs,
> +	.deinit_cb_devs = iris_vpu3x_deinit_cb_devs,
>  };
>  
>  const struct vpu_ops iris_vpu35_ops = {
> 
> -- 
> 2.34.1
> 

-- 
With best wishes
Dmitry