[PATCH 0/2] media: iris: add vbv delay support

[PATCH 0/2] media: iris: add vbv delay support

[Sachin Kumar Garg]

This series adds VBV_DELAY (V4L2_CID_MPEG_VIDEO_VBV_DELAY) support
for Qualcomm iris encoder sessions, allowing users to configure the
initial VBV (Video Buffer Verifier) delay for CBR-encoded streams.
This is useful for latency-sensitive encoding use cases (e.g.
low-latency streaming) where the client needs explicit control over
the encoder's buffering delay.

Patch 1 is a prerequisite for patch 2. The PIPE capability (control
over the number of VPP hardware pipes used for a session) was
previously only wired up for decoder sessions. Achieving low VBV delay
values (34-100 ms) requires the encoder to be constrained to a single
VPP pipe, so patch 1 enables the PIPE capability on the encoder path as
well, which patch 2 then relies on to force single-pipe operation when
VBV delay falls in that low-latency range.

Patch 2 adds the VBV_DELAY capability: it registers HFI_PROP_VBV_DELAY,
wires up the V4L2_CID_MPEG_VIDEO_VBV_DELAY control for the gen2
encoder, and only applies the property when rate control is set to CBR
since VBV delay is only meaningful for constant-bitrate encoding.
It adds vbv_delay support for iris HFI Gen2 based targets (qcs8300,
sm8550, sm8650, sm8750, x1p42100). Support for HFI Gen1 targets will
be added in a follow-up series.

This series has been verified with GST level testing.
Command used:
gst-launch-1.0 -v videotestsrc ! video/x-raw,format=NV12, \
width=1280,height=720,framerate=30/1 ! v4l2h264enc output-io-mode=4 \
capture-io-mode=4 extra-controls="controls,video_bitrate_mode=1, \
initial_delay_for_vbv_control=300;" ! filesink location=/opt/test_enc.h264

Signed-off-by: Sachin Kumar Garg <sachin.garg@oss.qualcomm.com>
---
Sachin Kumar Garg (2):
      media: iris: enable pipe for hfi gen2 encoder
      media: iris: add support for vbv delay

 drivers/media/platform/qcom/iris/iris_ctrls.c      | 47 ++++++++++++++++++++--
 drivers/media/platform/qcom/iris/iris_ctrls.h      |  1 +
 drivers/media/platform/qcom/iris/iris_hfi_gen2.c   | 19 ++++++++-
 .../platform/qcom/iris/iris_hfi_gen2_defines.h     |  1 +
 .../platform/qcom/iris/iris_platform_common.h      |  1 +
 5 files changed, 65 insertions(+), 4 deletions(-)
---
base-commit: a52e6f7923c17a672135b485ffd96fbd72f46267
change-id: 20260730-iris_vbv_delay-343d2fa30842

Best regards,
-- 
Sachin Kumar Garg <sachin.garg@oss.qualcomm.com>

[PATCH 1/2] media: iris: enable pipe for hfi gen2 encoder

[Sachin Kumar Garg]

Currently the PIPE capability (HFI_PROP_PIPE / work-route) is only
wired up for the HFI Gen2 decoder. Add a PIPE entry to the HFI Gen2
encoder instance capability table, and extend the encoder
branch of iris_session_init_caps() to derive PIPE's min/max/value
from the platform's num_vpp_pipe, mirroring the existing decoder
handling.

Signed-off-by: Sachin Kumar Garg <sachin.garg@oss.qualcomm.com>
---
 drivers/media/platform/qcom/iris/iris_ctrls.c    | 16 +++++++++++++---
 drivers/media/platform/qcom/iris/iris_hfi_gen2.c |  7 +++++++
 2 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/drivers/media/platform/qcom/iris/iris_ctrls.c b/drivers/media/platform/qcom/iris/iris_ctrls.c
index 10e33b8a73f6..33114d80aa68 100644
--- a/drivers/media/platform/qcom/iris/iris_ctrls.c
+++ b/drivers/media/platform/qcom/iris/iris_ctrls.c
@@ -453,13 +453,23 @@ void iris_session_init_caps(struct iris_core *core)
 			continue;
 
 		core->inst_fw_caps_enc[cap_id].cap_id = caps[i].cap_id;
-		core->inst_fw_caps_enc[cap_id].min = caps[i].min;
-		core->inst_fw_caps_enc[cap_id].max = caps[i].max;
 		core->inst_fw_caps_enc[cap_id].step_or_mask = caps[i].step_or_mask;
-		core->inst_fw_caps_enc[cap_id].value = caps[i].value;
 		core->inst_fw_caps_enc[cap_id].flags = caps[i].flags;
 		core->inst_fw_caps_enc[cap_id].hfi_id = caps[i].hfi_id;
 		core->inst_fw_caps_enc[cap_id].set = caps[i].set;
+
+		if (cap_id == PIPE) {
+			core->inst_fw_caps_enc[cap_id].value =
+				core->iris_platform_data->num_vpp_pipe;
+			core->inst_fw_caps_enc[cap_id].min =
+				core->iris_platform_data->num_vpp_pipe;
+			core->inst_fw_caps_enc[cap_id].max =
+				core->iris_platform_data->num_vpp_pipe;
+		} else {
+			core->inst_fw_caps_enc[cap_id].min = caps[i].min;
+			core->inst_fw_caps_enc[cap_id].max = caps[i].max;
+			core->inst_fw_caps_enc[cap_id].value = caps[i].value;
+		}
 	}
 }
 
diff --git a/drivers/media/platform/qcom/iris/iris_hfi_gen2.c b/drivers/media/platform/qcom/iris/iris_hfi_gen2.c
index acc0ed8adda1..45a418fde7e9 100644
--- a/drivers/media/platform/qcom/iris/iris_hfi_gen2.c
+++ b/drivers/media/platform/qcom/iris/iris_hfi_gen2.c
@@ -365,6 +365,13 @@ static const struct platform_inst_fw_cap inst_fw_cap_sm8550_enc[] = {
 		.hfi_id = HFI_PROP_STAGE,
 		.set = iris_set_stage,
 	},
+	{
+		.cap_id = PIPE,
+		/* .max, .min and .value are set via platform data */
+		.step_or_mask = 1,
+		.hfi_id = HFI_PROP_PIPE,
+		.set = iris_set_pipe,
+	},
 	{
 		.cap_id = HEADER_MODE,
 		.min = V4L2_MPEG_VIDEO_HEADER_MODE_SEPARATE,

-- 
2.34.1

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

[Sachin Kumar Garg]

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 <sachin.garg@oss.qualcomm.com>
---
 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