[PATCH 2/2] media: iris: add support for vbv delay

Sachin Kumar Garg <[email protected]> Thu, 30 Jul 2026 20:25:27 +0530
Newsgroups org.kernel.vger.linux-media,org.kernel.vger.linux-arm-msm,org.kernel.vger.linux-kernel
Message-ID <[email protected]>
Add the VBV_DELAY instance capability for the HFI Gen2 encoder,
exposed to userspace via V4L2_CID_MPEG_VIDEO_VBV_DELAY and mapped to
HFI_PROP_VBV_DELAY through a new iris_set_vbv_delay(). The property
is only meaningful for CBR rate-control modes.

Low VBV delay values (34-100 ms) require the encoder to run
with a single video pipe, so extend iris_set_pipe() to force
work_route to 1 whenever the configured VBV_DELAY falls in that
range.

Signed-off-by: Sachin Kumar Garg <[email protected]>
---
 drivers/media/platform/qcom/iris/iris_ctrls.c      | 31 ++++++++++++++++++++++
 drivers/media/platform/qcom/iris/iris_ctrls.h      |  1 +
 drivers/media/platform/qcom/iris/iris_hfi_gen2.c   | 12 ++++++++-
 .../platform/qcom/iris/iris_hfi_gen2_defines.h     |  1 +
 .../platform/qcom/iris/iris_platform_common.h      |  1 +
 5 files changed, 45 insertions(+), 1 deletion(-)

diff --git a/drivers/media/platform/qcom/iris/iris_ctrls.c b/drivers/media/platform/qcom/iris/iris_ctrls.c
index 33114d80aa68..0ad873f3be78 100644
--- a/drivers/media/platform/qcom/iris/iris_ctrls.c
+++ b/drivers/media/platform/qcom/iris/iris_ctrls.c
@@ -154,6 +154,8 @@ static enum platform_inst_fw_cap_type iris_get_cap_id(u32 id)
 		return LAYER4_BITRATE_HEVC;
 	case V4L2_CID_MPEG_VIDEO_HEVC_HIER_CODING_L5_BR:
 		return LAYER5_BITRATE_HEVC;
+	case V4L2_CID_MPEG_VIDEO_VBV_DELAY:
+		return VBV_DELAY;
 	default:
 		return INST_FW_CAP_MAX;
 	}
@@ -297,6 +299,8 @@ static u32 iris_get_v4l2_id(enum platform_inst_fw_cap_type cap_id)
 		return V4L2_CID_MPEG_VIDEO_HEVC_HIER_CODING_L4_BR;
 	case LAYER5_BITRATE_HEVC:
 		return V4L2_CID_MPEG_VIDEO_HEVC_HIER_CODING_L5_BR;
+	case VBV_DELAY:
+		return V4L2_CID_MPEG_VIDEO_VBV_DELAY;
 	default:
 		return 0;
 	}
@@ -544,6 +548,11 @@ int iris_set_pipe(struct iris_inst *inst, enum platform_inst_fw_cap_type cap_id)
 	u32 work_route = inst->fw_caps[PIPE].value;
 	u32 hfi_id = inst->fw_caps[cap_id].hfi_id;
 
+	if (inst->domain == ENCODER) {
+		if (inst->fw_caps[VBV_DELAY].value > 34 && inst->fw_caps[VBV_DELAY].value < 100)
+			work_route = 1;
+	}
+
 	return hfi_ops->session_set_property(inst, hfi_id,
 					     HFI_HOST_FLAGS_NONE,
 					     iris_get_port_info(inst, cap_id),
@@ -1487,6 +1496,28 @@ int iris_set_layer_bitrate(struct iris_inst *inst, enum platform_inst_fw_cap_typ
 					     &bitrate, sizeof(u32));
 }
 
+int iris_set_vbv_delay(struct iris_inst *inst, enum platform_inst_fw_cap_type cap_id)
+{
+	const struct iris_hfi_session_ops *hfi_ops = inst->hfi_session_ops;
+	u32 hfi_id = inst->fw_caps[cap_id].hfi_id;
+	u32 rc_type = inst->hfi_rc_type;
+	u32 hfi_val;
+
+	if (rc_type != HFI_RC_CBR_VFR &&
+	    rc_type != HFI_RC_CBR_CFR) {
+		dev_err(inst->core->dev, "vbv_delay unsupported, rc_type: %#x\n", rc_type);
+		return -EINVAL;
+	}
+
+	hfi_val = inst->fw_caps[cap_id].value;
+
+	return hfi_ops->session_set_property(inst, hfi_id,
+					     HFI_HOST_FLAGS_NONE,
+					     iris_get_port_info(inst, cap_id),
+					     HFI_PAYLOAD_U32,
+					     &hfi_val, sizeof(u32));
+}
+
 int iris_set_properties(struct iris_inst *inst, u32 plane)
 {
 	const struct iris_hfi_session_ops *hfi_ops = inst->hfi_session_ops;
diff --git a/drivers/media/platform/qcom/iris/iris_ctrls.h b/drivers/media/platform/qcom/iris/iris_ctrls.h
index 3c462ec9190b..16939e31c784 100644
--- a/drivers/media/platform/qcom/iris/iris_ctrls.h
+++ b/drivers/media/platform/qcom/iris/iris_ctrls.h
@@ -47,6 +47,7 @@ int iris_set_layer_type(struct iris_inst *inst, enum platform_inst_fw_cap_type c
 int iris_set_layer_count_gen1(struct iris_inst *inst, enum platform_inst_fw_cap_type cap_id);
 int iris_set_layer_count_gen2(struct iris_inst *inst, enum platform_inst_fw_cap_type cap_id);
 int iris_set_layer_bitrate(struct iris_inst *inst, enum platform_inst_fw_cap_type cap_id);
+int iris_set_vbv_delay(struct iris_inst *inst, enum platform_inst_fw_cap_type cap_id);
 int iris_set_properties(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 45a418fde7e9..716947f256f1 100644
--- a/drivers/media/platform/qcom/iris/iris_hfi_gen2.c
+++ b/drivers/media/platform/qcom/iris/iris_hfi_gen2.c
@@ -944,7 +944,17 @@ static const struct platform_inst_fw_cap inst_fw_cap_sm8550_enc[] = {
 		.flags = CAP_FLAG_OUTPUT_PORT | CAP_FLAG_INPUT_PORT |
 			CAP_FLAG_DYNAMIC_ALLOWED,
 		.set = iris_set_layer_bitrate,
-	}
+	},
+	{
+		.cap_id = VBV_DELAY,
+		.min = 34,
+		.max = 300,
+		.step_or_mask = 1,
+		.value = 300,
+		.hfi_id = HFI_PROP_VBV_DELAY,
+		.flags = CAP_FLAG_OUTPUT_PORT,
+		.set = iris_set_vbv_delay,
+	},
 };
 
 static const u32 sm8550_vdec_input_config_params_default[] = {
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 776b21cd11b2..19d04981cdb9 100644
--- a/drivers/media/platform/qcom/iris/iris_hfi_gen2_defines.h
+++ b/drivers/media/platform/qcom/iris/iris_hfi_gen2_defines.h
@@ -127,6 +127,7 @@ enum hfi_flip {
 #define HFI_PROP_BUFFER_MARK			0x0300016c
 #define HFI_PROP_WORST_COMPRESSION_RATIO	0x03000174
 #define HFI_PROP_WORST_COMPLEXITY_FACTOR	0x03000175
+#define HFI_PROP_VBV_DELAY			0x03000176
 #define HFI_PROP_RAW_RESOLUTION		0x03000178
 #define HFI_PROP_TOTAL_PEAK_BITRATE		0x0300017C
 #define HFI_PROP_AV1_FILM_GRAIN_PRESENT	0x03000180
diff --git a/drivers/media/platform/qcom/iris/iris_platform_common.h b/drivers/media/platform/qcom/iris/iris_platform_common.h
index c9256f2323dc..a533740ced7c 100644
--- a/drivers/media/platform/qcom/iris/iris_platform_common.h
+++ b/drivers/media/platform/qcom/iris/iris_platform_common.h
@@ -183,6 +183,7 @@ enum platform_inst_fw_cap_type {
 	LAYER3_BITRATE_HEVC,
 	LAYER4_BITRATE_HEVC,
 	LAYER5_BITRATE_HEVC,
+	VBV_DELAY,
 	INST_FW_CAP_MAX,
 };
 

-- 
2.34.1