Re: [PATCH 09/11] media: iris: Add support to select core for dual core platforms
From: Dmitry Baryshkov
Date: Tue Apr 14 2026 - 12:07:46 EST
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?
>
> Signed-off-by: Vishnu Reddy <busanna.reddy@xxxxxxxxxxxxxxxx>
> ---
> 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
>
--
With best wishes
Dmitry