Re: [PATCH v7 5/5] media: iris: Add BUF_ROIMB_DELTAQP metadata buffer for ROI delta QP

[Deepa Guthyappa Madivalara <deepa.madivalara@oss.qualcomm.com>]

On 9/30/2026 3:58 AM, Vishnu Reddy wrote:
> On 9/25/2026 5:58 AM, Deepa Guthyappa Madivalara wrote:
>> - Introduce BUF_ROIMB_DELTAQP as a new internal buffer type to carry
>>    per-macroblock ROI delta QP data to the firmware. This buffer is
>>    allocated on demand when the application sets ROI parameters via
>>    V4L2_CID_MPEG_VIDEO_ROI_MB_DELTA_QP, and is queued alongside each
>>    raw input buffer as an HFI_BUFFER_METADATA packet on HFI_PORT_RAW.
>>
>> - The metadata buffer layout follows the firmware-defined metabuf_header
>>    and metapayload_header structures. The s8 per-MB delta QP values
>>    supplied by userspace are widened to s16 as required by the firmware.
>>
>> Signed-off-by: Deepa Guthyappa Madivalara <deepa.madivalara@oss.qualcomm.com>
>> ---
>>   drivers/media/platform/qcom/iris/iris_buffer.c     | 114 +++++++++++++++++++++
>>   drivers/media/platform/qcom/iris/iris_buffer.h     |   4 +
>>   drivers/media/platform/qcom/iris/iris_ctrls.c      |  37 +++++++
>>   drivers/media/platform/qcom/iris/iris_ctrls.h      |   1 +
>>   drivers/media/platform/qcom/iris/iris_hfi_gen2.c   |   1 +
>>   .../platform/qcom/iris/iris_hfi_gen2_command.c     |  24 +++++
>>   .../platform/qcom/iris/iris_hfi_gen2_response.c    |   2 +
>>   drivers/media/platform/qcom/iris/iris_vidc.c       |   2 +
>>   8 files changed, 185 insertions(+)
>>
>> diff --git a/drivers/media/platform/qcom/iris/iris_buffer.c b/drivers/media/platform/qcom/iris/iris_buffer.c
>> index eb8de60c1177f5e1ab83b90a3c8c80e0b4d1f02e..a7f1d74360d6a490959b27936fa5bbc61a7d9358 100644
>> --- a/drivers/media/platform/qcom/iris/iris_buffer.c
>> +++ b/drivers/media/platform/qcom/iris/iris_buffer.c
>> @@ -5,11 +5,13 @@
>>   
>>   #include <media/v4l2-event.h>
>>   #include <media/v4l2-mem2mem.h>
>> +#include <linux/slab.h>
>>   
>>   #include "iris_buffer.h"
>>   #include "iris_instance.h"
>>   #include "iris_power.h"
>>   #include "iris_vpu_buffer.h"
>> +#include "iris_hfi_gen2_defines.h"
>>   
>>   #define PIXELS_4K 4096
>>   #define MAX_WIDTH 4096
>> @@ -705,6 +707,20 @@ int iris_destroy_dequeued_internal_buffers(struct iris_inst *inst, u32 plane)
>>   	return iris_destroy_internal_buffers(inst, plane, false);
>>   }
>>   
>> +int iris_destroy_roi_metadata_buffers(struct iris_inst *inst)
>> +{
>> +	struct iris_buffer *buf, *next;
>> +	struct iris_buffers *buffers;
>> +
>> +	if (inst->domain == ENCODER) {
>> +		buffers = &inst->buffers[BUF_ROIMB_DELTAQP];
>> +		list_for_each_entry_safe(buf, next, &buffers->list, list)
>> +			iris_destroy_internal_buffer(inst, buf);
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>>   static int iris_release_internal_buffers(struct iris_inst *inst,
>>   					 enum iris_buffer_type buffer_type)
>>   {
>> @@ -928,3 +944,101 @@ int iris_vb2_buffer_done(struct iris_inst *inst, struct iris_buffer *buf)
>>   
>>   	return 0;
>>   }
>> +
>> +static int iris_fill_roi_data(struct iris_inst *inst, struct iris_buffer *buffer)
>> +{
>> +	s8 *p_array = (s8 *)inst->fw_caps[ROI_PARAMS].p_array;
>> +	u32 payload_offset, lcu_width, lcu_height, row_size;
>> +	u32 array_size = inst->fw_caps[ROI_PARAMS].elems;
>> +	struct metabuf_header *mbuf_hdr = buffer->kvaddr;
>> +	struct metapayload_header *mbuf_payload_hdr;
>> +	struct v4l2_format *f = inst->fmt_src;
>> +	s16 *p_16, *p_temp;
>> +
>> +	memset(mbuf_hdr, 0, sizeof(struct metabuf_header));
>> +	mbuf_hdr->count = 1;
>> +	mbuf_hdr->size = sizeof(struct metabuf_header) +
>> +			 sizeof(struct metapayload_header);
>> +	mbuf_hdr->version = BIT(16);
>> +	mbuf_hdr++;
>> +	mbuf_payload_hdr = (struct metapayload_header *)(mbuf_hdr);
>> +	payload_offset = sizeof(struct metabuf_header) +
>> +			 sizeof(struct metapayload_header);
>> +
>> +	memset(mbuf_payload_hdr, 0, sizeof(struct metapayload_header));
>> +	mbuf_payload_hdr->type = HFI_PROP_ROI_INFO;
>> +	mbuf_payload_hdr->size = array_size * sizeof(s16);
>> +	mbuf_payload_hdr->version = 1 << 16;
>> +	mbuf_payload_hdr->offset = ALIGN(payload_offset, (u32)256);
>> +	mbuf_payload_hdr->flags = 0;
>> +
>> +	if (inst->codec == V4L2_PIX_FMT_HEVC) {
>> +		lcu_width = (f->fmt.pix_mp.width + 31) >> 5;
>> +		lcu_height = (f->fmt.pix_mp.height + 31) >> 5;
>> +	} else {
>> +		lcu_width = (f->fmt.pix_mp.width + 15) >> 4;
>> +		lcu_height = (f->fmt.pix_mp.height + 15) >> 4;
>> +	}
>> +	/* Firmware expects each row to align to 8 LCU */
>> +	row_size = (((lcu_width + 7) >> 3) << 3);
>> +
>> +	/* Firmware expects 2bytes of delta_Qp, int16_t */
>> +	p_16 = buffer->kvaddr + mbuf_payload_hdr->offset;
>> +	for (int j = 0; j < lcu_height; j++) {
>> +		p_temp = p_16 + j * row_size;
>> +		for (int i = 0; i < lcu_width; i++)
>> +			*p_temp++ = (1 << 11) | (((u8)p_array[j * lcu_width + i]
>> +						   & 0x3F) << 4);
>> +	}
>> +
>> +	return 0;
>> +}
>> +
>> +int iris_hfi_gen2_session_alloc_roi_metadata_buffer(struct iris_inst *inst)
>> +{
>> +	struct iris_buffers *buffers = &inst->buffers[BUF_ROIMB_DELTAQP];
>> +	struct iris_core *core = inst->core;
>> +	struct iris_buffer *buffer, *first_buffer, *next;
>> +	bool found = false;
>> +	int ret = 0;
>> +
>> +	if (!buffers->size)
>> +		return 0;
>> +
>> +	list_for_each_entry_safe(buffer, next, &buffers->list, list) {
>> +		if (buffer->attr & BUF_ATTR_DEQUEUED) {
>> +			buffer->attr &= ~BUF_ATTR_DEQUEUED;
>> +			list_move(&buffer->list, &buffers->list);
>> +			found = true;
>> +			break;
>> +		}
>> +	}
>> +	if (!found) {
>> +		buffer = kzalloc_obj(*buffer);
>> +		if (!buffer)
>> +			return -ENOMEM;
>> +
>> +		INIT_LIST_HEAD(&buffer->list);
>> +		buffer->type = BUF_ROIMB_DELTAQP;
>> +		buffer->index++;
>> +		buffer->buffer_size = buffers->size;
>> +		buffer->dma_attrs = DMA_ATTR_WRITE_COMBINE;
>> +
>> +		buffer->kvaddr = dma_alloc_attrs(core->dev, buffer->buffer_size,
>> +						 &buffer->device_addr, GFP_KERNEL,
>> +						 buffer->dma_attrs);
>> +
>> +		if (!buffer->kvaddr) {
>> +			kfree(buffer);
>> +			return -ENOMEM;
>> +		}
>> +		list_add(&buffer->list, &buffers->list);
>> +	}
>> +
>> +	first_buffer = list_first_entry(&buffers->list, struct iris_buffer, list);
>> +	ret = iris_fill_roi_data(inst, first_buffer);
>> +	if (ret)
>> +		return ret;
>> +
>> +	return ret;
>> +}
>> diff --git a/drivers/media/platform/qcom/iris/iris_buffer.h b/drivers/media/platform/qcom/iris/iris_buffer.h
>> index ee2d24bb69c57220b0a735d9b4aae4434a33daf6..df9d018493f3ec37fd5e6b0ba049dba0b5ae76e9 100644
>> --- a/drivers/media/platform/qcom/iris/iris_buffer.h
>> +++ b/drivers/media/platform/qcom/iris/iris_buffer.h
>> @@ -28,6 +28,7 @@ struct iris_inst;
>>    * @BUF_SCRATCH_2: buffer to store encoding context data for HW
>>    * @BUF_VPSS: buffer to store VPSS context data for HW
>>    * @BUF_PARTIAL: buffer for AV1 IBC data
>> + * @BUF_ROIMB_DELTAQP: metadata buffer for ROI MB DeltaQp
>>    * @BUF_TYPE_MAX: max buffer types
>>    */
>>   enum iris_buffer_type {
>> @@ -44,6 +45,7 @@ enum iris_buffer_type {
>>   	BUF_SCRATCH_2,
>>   	BUF_VPSS,
>>   	BUF_PARTIAL,
>> +	BUF_ROIMB_DELTAQP,
>>   	BUF_TYPE_MAX,
>>   };
>>   
>> @@ -139,5 +141,7 @@ int iris_queue_buffer(struct iris_inst *inst, struct iris_buffer *buf);
>>   int iris_queue_deferred_buffers(struct iris_inst *inst, enum iris_buffer_type buf_type);
>>   int iris_vb2_buffer_done(struct iris_inst *inst, struct iris_buffer *buf);
>>   void iris_vb2_queue_error(struct iris_inst *inst);
>> +int iris_hfi_gen2_session_alloc_roi_metadata_buffer(struct iris_inst *inst);
>> +int iris_destroy_roi_metadata_buffers(struct iris_inst *inst);
>>   
>>   #endif
>> diff --git a/drivers/media/platform/qcom/iris/iris_ctrls.c b/drivers/media/platform/qcom/iris/iris_ctrls.c
>> index 1ce8eccdedbdeb840833bd92edb3f59dd6962d7f..2ab20cacbc2b79ac4cf28eda88b15cae332c4160 100644
>> --- a/drivers/media/platform/qcom/iris/iris_ctrls.c
>> +++ b/drivers/media/platform/qcom/iris/iris_ctrls.c
>> @@ -1624,3 +1624,40 @@ int iris_set_metadata_delivery(struct iris_inst *inst, u32 plane)
>>   
>>   	return ret;
>>   }
>> +
>> +int iris_set_roi_params(struct iris_inst *inst, u32 plane)
>> +{
>> +	struct iris_buffers *buffers = &inst->buffers[BUF_ROIMB_DELTAQP];
>> +	u32 height = inst->fmt_src->fmt.pix_mp.height;
>> +	u32 width = inst->fmt_src->fmt.pix_mp.width;
>> +	u32 metadata_header_bytes = 256;
>> +	u32 lcu_height = 0;
>> +	u32 lcu_width = 0;
>> +	u32 lcu_size = 16;
>> +	u32 n_shift = 0;
>> +	u32 size = 0;
>> +	int ret = 0;
>> +
>> +	if (!inst->fw_caps[ROI_PARAMS].p_array)
>> +		return -EINVAL;
>> +
>> +	if (inst->codec == V4L2_PIX_FMT_HEVC)
>> +		lcu_size = 32;
>> +
>> +	while (lcu_size && !(lcu_size & 0x1)) {
>> +		n_shift++;
>> +		lcu_size = lcu_size >> 1;
> Since lcu_size can only be 16 or 32 here, is the loop needed?
> n_shift could be derived using ilog2(lcu_size), and the lcu_size reassignment
> below could also be avoided.
>
>> +	}
>> +
>> +	lcu_size = inst->codec == V4L2_PIX_FMT_HEVC ? 32 : 16;
>> +	lcu_width = (width + (lcu_size - 1)) >> n_shift;
>> +	lcu_height = (height + (lcu_size - 1)) >> n_shift;
>> +	size = (((lcu_width + 7) >> 3) << 3) * lcu_height * 2;
>> +	size += metadata_header_bytes;
>> +	buffers->size = ALIGN(size, 4096);
>> +	ret = iris_hfi_gen2_session_alloc_roi_metadata_buffer(inst);
>> +	if (ret)
>> +		return ret;
>> +
>> +	return 0;
> return iris_hfi_gen2_session_alloc_roi_metadata_buffer(inst);
>
>> +}
>> diff --git a/drivers/media/platform/qcom/iris/iris_ctrls.h b/drivers/media/platform/qcom/iris/iris_ctrls.h
>> index 9957b69366f50310338a0c1470d9744592655c33..7587dfec052a320863889eb15203416b9c527a40 100644
>> --- a/drivers/media/platform/qcom/iris/iris_ctrls.h
>> +++ b/drivers/media/platform/qcom/iris/iris_ctrls.h
>> @@ -51,5 +51,6 @@ int iris_set_req_sync_frame(struct iris_inst *inst, enum platform_inst_fw_cap_ty
>>   int iris_set_time_delta_based_rc(struct iris_inst *inst, enum platform_inst_fw_cap_type cap_id);
>>   int iris_set_properties(struct iris_inst *inst, u32 plane);
>>   int iris_set_metadata_delivery(struct iris_inst *inst, u32 plane);
>> +int iris_set_roi_params(struct iris_inst *inst, u32 plane);
>>   
>>   #endif
>> diff --git a/drivers/media/platform/qcom/iris/iris_hfi_gen2.c b/drivers/media/platform/qcom/iris/iris_hfi_gen2.c
>> index d628bc6748438b19dac01cd11cb9f8da0b8500af..4d40d6733e5877a302ce63fb0b4a61b8f284e6dc 100644
>> --- a/drivers/media/platform/qcom/iris/iris_hfi_gen2.c
>> +++ b/drivers/media/platform/qcom/iris/iris_hfi_gen2.c
>> @@ -1789,6 +1789,7 @@ static const struct platform_inst_fw_cap inst_fw_cap_sm8550_enc[] = {
>>   		.hfi_id = HFI_PROP_ROI_INFO,
>>   		.flags = CAP_FLAG_INPUT_PORT | CAP_FLAG_CUSTOM |
>>   			 CAP_FLAG_DYNAMIC_ALLOWED,
>> +		.set = iris_set_roi_params,
>>   	},
>>   	{
>>   		.cap_id = MB_SIZE,
>> 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 cf88dbe11e8e9faef826e661d8e9909fd7f16b94..a1b0c4982f0d789a807f22a1dffdf61decd20d28 100644
>> --- a/drivers/media/platform/qcom/iris/iris_hfi_gen2_command.c
>> +++ b/drivers/media/platform/qcom/iris/iris_hfi_gen2_command.c
>> @@ -134,6 +134,7 @@ static u32 iris_hfi_gen2_get_port_from_buf_type(struct iris_inst *inst,
>>   		switch (buffer_type) {
>>   		case BUF_INPUT:
>>   		case BUF_VPSS:
>> +		case BUF_ROIMB_DELTAQP:
>>   			return HFI_PORT_RAW;
>>   		case BUF_OUTPUT:
>>   		case BUF_BIN:
>> @@ -1267,6 +1268,8 @@ static u32 iris_hfi_gen2_buf_type_from_driver(u32 domain, enum iris_buffer_type
>>   		return HFI_BUFFER_VPSS;
>>   	case BUF_PARTIAL:
>>   		return HFI_BUFFER_PARTIAL_DATA;
>> +	case BUF_ROIMB_DELTAQP:
>> +		return HFI_BUFFER_METADATA;
>>   	default:
>>   		return 0;
>>   	}
>> @@ -1328,6 +1331,7 @@ static struct iris_buffer *iris_queue_metadata_buffers(struct iris_inst *inst,
>>   static int iris_hfi_gen2_session_queue_buffer(struct iris_inst *inst, struct iris_buffer *buffer)
>>   {
>>   	struct iris_inst_hfi_gen2 *inst_hfi_gen2 = to_iris_inst_hfi_gen2(inst);
>> +	struct iris_hfi_buffer hfi_meta_buffer;
>>   	struct iris_hfi_buffer hfi_buffer;
>>   	u32 port;
>>   	int ret;
>> @@ -1349,6 +1353,26 @@ static int iris_hfi_gen2_session_queue_buffer(struct iris_inst *inst, struct iri
>>   					     &hfi_buffer,
>>   					     sizeof(hfi_buffer));
>>   
>> +	/* check if any metadata buffer is available not queued, queue it */
>> +	if (port == HFI_PORT_RAW) {
>> +		buffer = iris_queue_metadata_buffers(inst, BUF_ROIMB_DELTAQP, buffer->index);
>> +		if (buffer) {
>> +			iris_hfi_gen2_get_buffer(inst->domain, buffer, &hfi_meta_buffer);
>> +			port = iris_hfi_gen2_get_port_from_buf_type(inst, buffer->type);
>> +			iris_hfi_gen2_create_packet(inst_hfi_gen2->packet,
>> +						    HFI_CMD_BUFFER,
>> +						    HFI_HOST_FLAGS_INTR_REQUIRED,
>> +						    HFI_PAYLOAD_STRUCTURE,
>> +						    port,
>> +						    inst->core->packet_id++,
>> +						    &hfi_meta_buffer,
>> +						    sizeof(hfi_meta_buffer));
>> +
>> +			buffer->attr |= BUF_ATTR_QUEUED;
>> +			buffer->attr &= ~BUF_ATTR_DEQUEUED;
> If iris_queue_buffer() is the only caller, is this needed?
> The caller already updates QUEUED attribute on successful return.
This makes it clear that the buffer is actually is not dequeued yet, 
while I am searching for a
free buffer in iris_hfi_gen2_session_alloc_roi_metadata_buffer.
>> +		}
>> +	}
>> +
>>   	return iris_hfi_queue_cmd_write(inst->core, inst_hfi_gen2->packet,
>>   					inst_hfi_gen2->packet->size);
>>   }
>> diff --git a/drivers/media/platform/qcom/iris/iris_hfi_gen2_response.c b/drivers/media/platform/qcom/iris/iris_hfi_gen2_response.c
>> index 84b629b957442c024dccc18b354ac9a7e541abaa..f63e0a7723e8583da818c2b004e367c1dd3d94f7 100644
>> --- a/drivers/media/platform/qcom/iris/iris_hfi_gen2_response.c
>> +++ b/drivers/media/platform/qcom/iris/iris_hfi_gen2_response.c
>> @@ -58,6 +58,8 @@ static u32 iris_hfi_gen2_buf_type_to_driver(struct iris_inst *inst,
>>   		return BUF_PARTIAL;
>>   	case HFI_BUFFER_VPSS:
>>   		return BUF_VPSS;
>> +	case HFI_BUFFER_METADATA:
>> +		return BUF_ROIMB_DELTAQP;
>>   	default:
>>   		return 0;
>>   	}
>> diff --git a/drivers/media/platform/qcom/iris/iris_vidc.c b/drivers/media/platform/qcom/iris/iris_vidc.c
>> index fcbc60016beec693f2ce27927a09a2d51494bc38..fae3d113a9dc990f06167ee0b7fb8fab24a0552c 100644
>> --- a/drivers/media/platform/qcom/iris/iris_vidc.c
>> +++ b/drivers/media/platform/qcom/iris/iris_vidc.c
>> @@ -180,6 +180,7 @@ int iris_open(struct file *filp)
>>   	INIT_LIST_HEAD(&inst->buffers[BUF_SCRATCH_2].list);
>>   	INIT_LIST_HEAD(&inst->buffers[BUF_VPSS].list);
>>   	INIT_LIST_HEAD(&inst->buffers[BUF_PARTIAL].list);
>> +	INIT_LIST_HEAD(&inst->buffers[BUF_ROIMB_DELTAQP].list);
>>   	init_completion(&inst->completion);
>>   	init_completion(&inst->flush_completion);
>>   
>> @@ -299,6 +300,7 @@ int iris_close(struct file *filp)
>>   	iris_destroy_all_internal_buffers(inst, V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE);
>>   	iris_check_num_queued_internal_buffers(inst, V4L2_BUF_TYPE_VIDEO_OUTPUT_MPLANE);
>>   	iris_check_num_queued_internal_buffers(inst, V4L2_BUF_TYPE_VIDEO_CAPTURE_MPLANE);
>> +	iris_destroy_roi_metadata_buffers(inst);
>>   	iris_remove_session(inst);
>>   	mutex_unlock(&inst->lock);
>>   	mutex_destroy(&inst->ctx_q_lock);
>>