Re: [PATCH v2 4/7] media: iris: add context bank devices using iommu-map

[Dmitry Baryshkov]

On Fri, Feb 27, 2026 at 07:41:20PM +0530, Vikash Garodia wrote:
> Introduce different context banks(CB) and the associated buffer region.
> Different stream IDs from VPU would be associated to one of these CB.
> Multiple CBs are needed to increase the IOVA for the video usecases like
> higher concurrent sessions.
> 
> Co-developed-by: Vishnu Reddy <busanna.reddy@xxxxxxxxxxxxxxxx>
> Signed-off-by: Vishnu Reddy <busanna.reddy@xxxxxxxxxxxxxxxx>
> Signed-off-by: Vikash Garodia <vikash.garodia@xxxxxxxxxxxxxxxx>
> ---
>  .../platform/qcom/iris/iris_platform_common.h      | 18 +++++++
>  drivers/media/platform/qcom/iris/iris_probe.c      | 60 ++++++++++++++++++++--
>  drivers/media/platform/qcom/iris/iris_resources.c  | 36 +++++++++++++
>  drivers/media/platform/qcom/iris/iris_resources.h  |  1 +
>  4 files changed, 111 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/media/platform/qcom/iris/iris_platform_common.h b/drivers/media/platform/qcom/iris/iris_platform_common.h
> index 5a489917580eb10022fdcb52f7321a915e8b239d..03c50d6e54853fca34d7d32f65d09eb80945fcdd 100644
> --- a/drivers/media/platform/qcom/iris/iris_platform_common.h
> +++ b/drivers/media/platform/qcom/iris/iris_platform_common.h
> @@ -204,6 +204,22 @@ struct icc_vote_data {
>  	u32 fps;
>  };
>  
> +enum iris_buffer_region {
> +	IRIS_BITSTREAM_REGION		= BIT(0),
> +	IRIS_NON_PIXEL_REGION		= BIT(1),
> +	IRIS_PIXEL_REGION		= BIT(2),
> +	IRIS_SECURE_BITSTREAM_REGION	= BIT(3),
> +	IRIS_SECURE_NON_PIXEL_REGION	= BIT(4),
> +	IRIS_SECURE_PIXEL_REGION	= BIT(5),

Can a context bank belong to multiple regions at the same time?

> +};
> +
> +struct iris_context_bank {
> +	struct device *dev;

Separate data and the actual device. Define a wrapper around struct
device for the actual runtime usage.

> +	const char *name;
> +	const u32 f_id;
> +	const enum iris_buffer_region region;
> +};
> +
>  enum platform_pm_domain_type {
>  	IRIS_CTRL_POWER_DOMAIN,
>  	IRIS_HW_POWER_DOMAIN,
> @@ -246,6 +262,8 @@ struct iris_platform_data {
>  	u32 inst_fw_caps_enc_size;
>  	const struct tz_cp_config *tz_cp_config_data;
>  	u32 tz_cp_config_data_size;
> +	struct iris_context_bank *cb_data;
> +	u32 cb_data_size;

Do they differ from platform to platform? Mark them as const, it should
be data only.

>  	u32 core_arch;
>  	u32 hw_response_timeout;
>  	struct ubwc_config_data *ubwc_config;
> diff --git a/drivers/media/platform/qcom/iris/iris_probe.c b/drivers/media/platform/qcom/iris/iris_probe.c
> index ddaacda523ecb9990af0dd0640196223fbcc2cab..557adb038328a75510591d91569819abc0b7b1c9 100644
> --- a/drivers/media/platform/qcom/iris/iris_probe.c
> +++ b/drivers/media/platform/qcom/iris/iris_probe.c
> @@ -123,6 +123,49 @@ static int iris_init_resets(struct iris_core *core)
>  				     core->iris_platform_data->controller_rst_tbl_size);
>  }
>  
> +static void iris_destroy_child_device(struct iris_context_bank *cb)
> +{
> +	struct device *dev = cb->dev;
> +
> +	if (dev)
> +		device_unregister(dev);
> +
> +	cb->dev = NULL;
> +}
> +
> +static void iris_deinit_context_bank_devices(struct iris_core *core)
> +{
> +	struct iris_context_bank *cb;
> +	int i;
> +
> +	for (i = 0; i < core->iris_platform_data->cb_data_size; i++) {
> +		cb = &core->iris_platform_data->cb_data[i];
> +		iris_destroy_child_device(cb);
> +	}
> +}
> +
> +static int iris_init_context_bank_devices(struct iris_core *core)
> +{
> +	struct iris_context_bank *cb;
> +	int ret, i;
> +
> +	for (i = 0; i < core->iris_platform_data->cb_data_size; i++) {
> +		cb = &core->iris_platform_data->cb_data[i];
> +
> +		ret = iris_create_child_device_and_map(core, cb);
> +		if (ret)
> +			goto err_deinit_cb;
> +	}
> +
> +	return 0;
> +
> +err_deinit_cb:
> +	while (i-- > 0)
> +		iris_destroy_child_device(&core->iris_platform_data->cb_data[i]);
> +
> +	return ret;
> +}
> +
>  static int iris_init_resources(struct iris_core *core)
>  {
>  	int ret;
> @@ -193,6 +236,7 @@ static void iris_remove(struct platform_device *pdev)
>  		return;
>  
>  	iris_core_deinit(core);
> +	iris_deinit_context_bank_devices(core);
>  
>  	video_unregister_device(core->vdev_dec);
>  	video_unregister_device(core->vdev_enc);
> @@ -275,12 +319,18 @@ static int iris_probe(struct platform_device *pdev)
>  
>  	platform_set_drvdata(pdev, core);
>  
> -	dma_mask = core->iris_platform_data->dma_mask;
> -
> -	ret = dma_set_mask_and_coherent(dev, dma_mask);
> +	ret = iris_init_context_bank_devices(core);
>  	if (ret)
>  		goto err_vdev_unreg_enc;
>  
> +	dma_mask = core->iris_platform_data->dma_mask;
> +
> +	if (device_iommu_mapped(core->dev)) {
> +		ret = dma_set_mask_and_coherent(core->dev, dma_mask);
> +		if (ret)
> +			goto err_deinit_cb;
> +	}
> +
>  	dma_set_max_seg_size(&pdev->dev, DMA_BIT_MASK(32));
>  	dma_set_seg_boundary(&pdev->dev, DMA_BIT_MASK(32));
>  
> @@ -288,10 +338,12 @@ static int iris_probe(struct platform_device *pdev)
>  	pm_runtime_use_autosuspend(core->dev);
>  	ret = devm_pm_runtime_enable(core->dev);
>  	if (ret)
> -		goto err_vdev_unreg_enc;
> +		goto err_deinit_cb;
>  
>  	return 0;
>  
> +err_deinit_cb:
> +	iris_deinit_context_bank_devices(core);
>  err_vdev_unreg_enc:
>  	video_unregister_device(core->vdev_enc);
>  err_vdev_unreg_dec:
> diff --git a/drivers/media/platform/qcom/iris/iris_resources.c b/drivers/media/platform/qcom/iris/iris_resources.c
> index 773f6548370a257b8ae7332242544266cbbd61a9..be58e8620086d0f82c2c2bda29247483f5c56d79 100644
> --- a/drivers/media/platform/qcom/iris/iris_resources.c
> +++ b/drivers/media/platform/qcom/iris/iris_resources.c
> @@ -6,6 +6,7 @@
>  #include <linux/clk.h>
>  #include <linux/devfreq.h>
>  #include <linux/interconnect.h>
> +#include <linux/iris_vpu_bus.h>
>  #include <linux/pm_domain.h>
>  #include <linux/pm_opp.h>
>  #include <linux/pm_runtime.h>
> @@ -141,3 +142,38 @@ int iris_disable_unprepare_clock(struct iris_core *core, enum platform_clk_type
>  
>  	return 0;
>  }
> +
> +static void iris_device_release(struct device *dev)
> +{
> +	dev_set_drvdata(dev, NULL);
> +	kfree(dev);
> +}
> +
> +int iris_create_child_device_and_map(struct iris_core *core, struct iris_context_bank *cb)
> +{
> +	struct device *dev;
> +	int ret;
> +
> +	dev = kzalloc_obj(*dev);
> +	if (!dev)
> +		return -ENOMEM;
> +
> +	dev->release = iris_device_release;
> +	dev->bus = &iris_vpu_bus_type;
> +	dev->parent = core->dev;
> +	dev->coherent_dma_mask = core->iris_platform_data->dma_mask;
> +	dev->dma_mask = &dev->coherent_dma_mask;
> +
> +	dev_set_name(dev, "%s", cb->name);
> +	dev_set_drvdata(dev, cb);
> +
> +	ret = device_register(dev);
> +	if (ret) {
> +		put_device(dev);
> +		return ret;
> +	}
> +
> +	cb->dev = dev;
> +
> +	return 0;
> +}
> diff --git a/drivers/media/platform/qcom/iris/iris_resources.h b/drivers/media/platform/qcom/iris/iris_resources.h
> index 6bfbd2dc6db095ec05e53c894e048285f82446c6..b7efe15facb203eea9ae13d5f0abdcc2ea718b4d 100644
> --- a/drivers/media/platform/qcom/iris/iris_resources.h
> +++ b/drivers/media/platform/qcom/iris/iris_resources.h
> @@ -15,5 +15,6 @@ int iris_unset_icc_bw(struct iris_core *core);
>  int iris_set_icc_bw(struct iris_core *core, unsigned long icc_bw);
>  int iris_disable_unprepare_clock(struct iris_core *core, enum platform_clk_type clk_type);
>  int iris_prepare_enable_clock(struct iris_core *core, enum platform_clk_type clk_type);
> +int iris_create_child_device_and_map(struct iris_core *core, struct iris_context_bank *cb);
>  
>  #endif
> 
> -- 
> 2.34.1
> 

-- 
With best wishes
Dmitry