Re: [PATCH 09/11] media: iris: Add support to select core for dual core platforms

[Vikash Garodia <vikash.garodia@oss.qualcomm.com>]

On 4/14/2026 9:32 PM, Dmitry Baryshkov wrote:
> On Tue, Apr 14, 2026 at 10:30:05AM +0530, Vishnu Reddy wrote:
>> Select the hardware core (vcodec) for a session, based on load when the
>> platform supports dual vcodec cores. Assign the session to vcodec if its
>> MBPF/MBPS capacity allows it, otherwise assign to vcodec1. Communicate
>> the selected vcodec core to firmware using new HFI_PROP_CORE_ID property.
> 
> Is it possibly do dynamically control power to those codec cores? Is it
> possible to shutdown unused vcodec?
> 

VPU core GDSCs are HW_CTRLed, so VPU does gate these GDSCs when not 
used, and even inbetween frames dynamically. So effectively it would not 
do any better doing the same thing in software.

Regards,
Vikash
>>
>> Signed-off-by: Vishnu Reddy <busanna.reddy@oss.qualcomm.com>
>> ---
>>   drivers/media/platform/qcom/iris/iris_common.c     |  7 +++
>>   drivers/media/platform/qcom/iris/iris_hfi_common.h |  1 +
>>   .../platform/qcom/iris/iris_hfi_gen2_command.c     | 19 ++++++
>>   .../platform/qcom/iris/iris_hfi_gen2_defines.h     |  1 +
>>   drivers/media/platform/qcom/iris/iris_instance.h   |  2 +
>>   .../platform/qcom/iris/iris_platform_common.h      |  1 +
>>   drivers/media/platform/qcom/iris/iris_utils.c      | 68 +++++++++++++++++-----
>>   7 files changed, 83 insertions(+), 16 deletions(-)
>>
>> diff --git a/drivers/media/platform/qcom/iris/iris_common.c b/drivers/media/platform/qcom/iris/iris_common.c
>> index 7f1c7fe144f7..e31d4c988c55 100644
>> --- a/drivers/media/platform/qcom/iris/iris_common.c
>> +++ b/drivers/media/platform/qcom/iris/iris_common.c
>> @@ -49,11 +49,18 @@ void iris_set_ts_metadata(struct iris_inst *inst, struct vb2_v4l2_buffer *vbuf)
>>   int iris_process_streamon_input(struct iris_inst *inst)
>>   {
>>   	const struct iris_hfi_command_ops *hfi_ops = inst->core->hfi_ops;
>> +	bool dual_core = inst->core->iris_platform_data->dual_core;
> 
> inline
> 
>>   	enum iris_inst_sub_state set_sub_state = 0;
>>   	int ret;
>>   
>>   	iris_scale_power(inst);
>>   
>> +	if (dual_core) {
>> +		ret = hfi_ops->session_set_core_id(inst, inst->core_id);
>> +		if (ret)
>> +			return ret;
>> +	}
>> +
>>   	ret = hfi_ops->session_start(inst, V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE);
>>   	if (ret)
>>   		return ret;
>> diff --git a/drivers/media/platform/qcom/iris/iris_hfi_common.h b/drivers/media/platform/qcom/iris/iris_hfi_common.h
>> index 3edb5ae582b4..fbaf852a6b99 100644
>> --- a/drivers/media/platform/qcom/iris/iris_hfi_common.h
>> +++ b/drivers/media/platform/qcom/iris/iris_hfi_common.h
>> @@ -124,6 +124,7 @@ struct iris_hfi_command_ops {
>>   	int (*session_drain)(struct iris_inst *inst, u32 plane);
>>   	int (*session_resume_drain)(struct iris_inst *inst, u32 plane);
>>   	int (*session_close)(struct iris_inst *inst);
>> +	int (*session_set_core_id)(struct iris_inst *inst, u32 core_id);
>>   };
>>   
>>   struct iris_hfi_response_ops {
>> diff --git a/drivers/media/platform/qcom/iris/iris_hfi_gen2_command.c b/drivers/media/platform/qcom/iris/iris_hfi_gen2_command.c
>> index 30bfd90d423b..9d9fae587297 100644
>> --- a/drivers/media/platform/qcom/iris/iris_hfi_gen2_command.c
>> +++ b/drivers/media/platform/qcom/iris/iris_hfi_gen2_command.c
>> @@ -1300,6 +1300,24 @@ static int iris_hfi_gen2_session_release_buffer(struct iris_inst *inst, struct i
>>   					inst_hfi_gen2->packet->size);
>>   }
>>   
>> +static int iris_hfi_gen2_set_core_id(struct iris_inst *inst, u32 core_id)
>> +{
>> +	struct iris_inst_hfi_gen2 *inst_hfi_gen2 = to_iris_inst_hfi_gen2(inst);
>> +	u32 payload = core_id;
>> +
>> +	iris_hfi_gen2_packet_session_command(inst,
>> +					     HFI_PROP_CORE_ID,
>> +					     HFI_HOST_FLAGS_NONE,
>> +					     HFI_PORT_NONE,
>> +					     inst->session_id,
>> +					     HFI_PAYLOAD_U32,
>> +					     &payload,
>> +					     sizeof(u32));
>> +
>> +	return iris_hfi_queue_cmd_write(inst->core, inst_hfi_gen2->packet,
>> +					inst_hfi_gen2->packet->size);
>> +}
>> +
>>   static const struct iris_hfi_command_ops iris_hfi_gen2_command_ops = {
>>   	.sys_init = iris_hfi_gen2_sys_init,
>>   	.sys_image_version = iris_hfi_gen2_sys_image_version,
>> @@ -1317,6 +1335,7 @@ static const struct iris_hfi_command_ops iris_hfi_gen2_command_ops = {
>>   	.session_drain = iris_hfi_gen2_session_drain,
>>   	.session_resume_drain = iris_hfi_gen2_session_resume_drain,
>>   	.session_close = iris_hfi_gen2_session_close,
>> +	.session_set_core_id = iris_hfi_gen2_set_core_id,
>>   };
>>   
>>   void iris_hfi_gen2_command_ops_init(struct iris_core *core)
>> diff --git a/drivers/media/platform/qcom/iris/iris_hfi_gen2_defines.h b/drivers/media/platform/qcom/iris/iris_hfi_gen2_defines.h
>> index cecf771c55dd..1926a5344427 100644
>> --- a/drivers/media/platform/qcom/iris/iris_hfi_gen2_defines.h
>> +++ b/drivers/media/platform/qcom/iris/iris_hfi_gen2_defines.h
>> @@ -56,6 +56,7 @@
>>   #define HFI_PROP_BUFFER_HOST_MAX_COUNT		0x03000123
>>   #define HFI_PROP_BUFFER_FW_MIN_OUTPUT_COUNT	0x03000124
>>   #define HFI_PROP_PIC_ORDER_CNT_TYPE		0x03000128
>> +#define HFI_PROP_CORE_ID			0x030001A9
> 
> lowercase hex
> 
>>   
>>   enum hfi_rate_control {
>>   	HFI_RC_VBR_CFR		= 0x00000000,
>> diff --git a/drivers/media/platform/qcom/iris/iris_instance.h b/drivers/media/platform/qcom/iris/iris_instance.h
>> index 16965150f427..dd341ca5be57 100644
>> --- a/drivers/media/platform/qcom/iris/iris_instance.h
>> +++ b/drivers/media/platform/qcom/iris/iris_instance.h
>> @@ -37,6 +37,7 @@ struct iris_fmt {
>>    *
>>    * @list: used for attach an instance to the core
>>    * @core: pointer to core structure
>> + * @core_id: specifies the hardware core on which the session runs
>>    * @session_id: id of current video session
>>    * @ctx_q_lock: lock to serialize queues related ioctls
>>    * @lock: lock to seralise forward and reverse threads
>> @@ -79,6 +80,7 @@ struct iris_fmt {
>>   struct iris_inst {
>>   	struct list_head		list;
>>   	struct iris_core		*core;
>> +	u32				core_id;
>>   	u32				session_id;
>>   	struct mutex			ctx_q_lock;/* lock to serialize queues related ioctls */
>>   	struct mutex			lock; /* lock to serialize forward and reverse threads */
>> diff --git a/drivers/media/platform/qcom/iris/iris_platform_common.h b/drivers/media/platform/qcom/iris/iris_platform_common.h
>> index e3c1aff770dd..aeb70f54be10 100644
>> --- a/drivers/media/platform/qcom/iris/iris_platform_common.h
>> +++ b/drivers/media/platform/qcom/iris/iris_platform_common.h
>> @@ -258,6 +258,7 @@ struct iris_platform_data {
>>   	const struct tz_cp_config *tz_cp_config_data;
>>   	u32 tz_cp_config_data_size;
>>   	u32 core_arch;
>> +	bool dual_core;
>>   	u32 hw_response_timeout;
>>   	struct ubwc_config_data *ubwc_config;
>>   	u32 num_vpp_pipe;
>> diff --git a/drivers/media/platform/qcom/iris/iris_utils.c b/drivers/media/platform/qcom/iris/iris_utils.c
>> index cfc5b576ec56..38ede9f76d0b 100644
>> --- a/drivers/media/platform/qcom/iris/iris_utils.c
>> +++ b/drivers/media/platform/qcom/iris/iris_utils.c
>> @@ -90,18 +90,51 @@ struct iris_inst *iris_get_instance(struct iris_core *core, u32 session_id)
>>   	return NULL;
>>   }
>>   
>> -int iris_check_core_mbpf(struct iris_inst *inst)
>> +static u32 iris_get_mbps(struct iris_inst *inst)
>>   {
>> -	struct iris_core *core = inst->core;
>> -	struct iris_inst *instance;
>> -	u32 total_mbpf = 0;
>> +	u32 fps = max(inst->frame_rate, inst->operating_rate);
>> +
>> +	return iris_get_mbpf(inst) * fps;
>> +}
>> +
>> +static void iris_get_core_load(struct iris_core *core, u32 *core_load, bool mbpf)
>> +{
>> +	bool dual_core = core->iris_platform_data->dual_core;
>> +	struct iris_inst *inst;
>> +	u32 load;
>>   
>>   	mutex_lock(&core->lock);
>> -	list_for_each_entry(instance, &core->instances, list)
>> -		total_mbpf += iris_get_mbpf(instance);
>> +	list_for_each_entry(inst, &core->instances, list) {
>> +		if (mbpf)
>> +			load = iris_get_mbpf(inst);
>> +		else
>> +			load = iris_get_mbps(inst);
>> +
>> +		if (inst->core_id == BIT(0))
>> +			core_load[0] += load;
>> +		else if (dual_core && inst->core_id == BIT(1))
>> +			core_load[1] += load;
>> +	}
>>   	mutex_unlock(&core->lock);
>> +}
>>   
>> -	if (total_mbpf > core->iris_platform_data->max_core_mbpf)
>> +int iris_check_core_mbpf(struct iris_inst *inst)
>> +{
>> +	struct iris_core *core = inst->core;
>> +	u32 max_core_mbpf = core->iris_platform_data->max_core_mbpf;
>> +	bool dual_core = core->iris_platform_data->dual_core;
>> +	u32 core_mbpf[2] = {0, 0}, new_mbpf;
>> +
>> +	inst->core_id = 0;
>> +	iris_get_core_load(core, core_mbpf, true);
>> +	new_mbpf = iris_get_mbpf(inst);
>> +
>> +	if (core_mbpf[0] + new_mbpf <= max_core_mbpf)
>> +		inst->core_id = BIT(0);
>> +	else if (dual_core && core_mbpf[1] + new_mbpf <= max_core_mbpf)
>> +		inst->core_id = BIT(1);
>> +
>> +	if (!inst->core_id)
>>   		return -ENOMEM;
>>   
>>   	return 0;
>> @@ -110,17 +143,20 @@ int iris_check_core_mbpf(struct iris_inst *inst)
>>   int iris_check_core_mbps(struct iris_inst *inst)
>>   {
>>   	struct iris_core *core = inst->core;
>> -	struct iris_inst *instance;
>> -	u32 total_mbps = 0, fps = 0;
>> +	u32 max_core_mbps = core->iris_platform_data->max_core_mbps;
>> +	bool dual_core = core->iris_platform_data->dual_core;
>> +	u32 core_mbps[2] = {0, 0}, new_mbps;
>>   
>> -	mutex_lock(&core->lock);
>> -	list_for_each_entry(instance, &core->instances, list) {
>> -		fps = max(instance->frame_rate, instance->operating_rate);
>> -		total_mbps += iris_get_mbpf(instance) * fps;
>> -	}
>> -	mutex_unlock(&core->lock);
>> +	inst->core_id = 0;
>> +	iris_get_core_load(core, core_mbps, false);
>> +	new_mbps = iris_get_mbps(inst);
>> +
>> +	if (core_mbps[0] + new_mbps <= max_core_mbps)
>> +		inst->core_id = BIT(0);
>> +	else if (dual_core && core_mbps[1] + new_mbps <= max_core_mbps)
>> +		inst->core_id = BIT(1);
> 
> else return -ENOMEM.
> 
> But... Which of the checks will be used in the wild? Will it be
> iris_check_core_mbpf() or iris_check_core_mbps()? What if they disagree?
> 
>>   
>> -	if (total_mbps > core->iris_platform_data->max_core_mbps)
>> +	if (!inst->core_id)
>>   		return -ENOMEM;
>>   
>>   	return 0;
>>
>> -- 
>> 2.34.1
>>
>