[PATCH v4 0/3] Venus dynamic debug

[PATCH v4 0/3] Venus dynamic debug

[Stanimir Varbanov]

Hello,

Time for v4 with following changes:
 * 1/3 taken comments into account - Greg KH
 * 2/3 kept the patch version from v2.

Cc: jim.cromie@gmail.com
Cc: Joe Perches <joe@perches.com>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

I decided to keep 2/3 as it was in v2 of the current patchset
where the grouping of KERN_DEBUG messages has been accomplished
by dynamic debug 'format' filter. Depending on how WIP patches
from Jim [1] will progress I'm ready to change that. Until then
I'd like to have a  way to group the debug messages.
In case 2/3 is not accepted I'm willing to drop it from next
pull request.

v3 can be found at [2].

regards.
Stan

[1] https://lore.kernel.org/lkml/20200613155738.2249399-1-jim.cromie@gmail.com/T/#t
[2] https://lore.kernel.org/lkml/20200609104604.1594-1-stanimir.varbanov@linaro.org/

Stanimir Varbanov (3):
  venus: Add debugfs interface to set firmware log level
  venus: Make debug infrastructure more flexible
  venus: Add a debugfs file for SSR trigger

 drivers/media/platform/qcom/venus/Makefile    |  2 +-
 drivers/media/platform/qcom/venus/core.c      |  3 +
 drivers/media/platform/qcom/venus/core.h      |  8 +++
 drivers/media/platform/qcom/venus/dbgfs.c     | 51 +++++++++++++++
 drivers/media/platform/qcom/venus/dbgfs.h     | 12 ++++
 drivers/media/platform/qcom/venus/helpers.c   |  2 +-
 drivers/media/platform/qcom/venus/hfi_msgs.c  | 30 ++++-----
 drivers/media/platform/qcom/venus/hfi_venus.c | 27 ++++++--
 .../media/platform/qcom/venus/pm_helpers.c    |  3 +-
 drivers/media/platform/qcom/venus/vdec.c      | 63 +++++++++++++++++--
 drivers/media/platform/qcom/venus/venc.c      |  4 ++
 11 files changed, 172 insertions(+), 33 deletions(-)
 create mode 100644 drivers/media/platform/qcom/venus/dbgfs.c
 create mode 100644 drivers/media/platform/qcom/venus/dbgfs.h

-- 
2.17.1

[PATCH v4 1/3] venus: Add debugfs interface to set firmware log level

[Stanimir Varbanov]

This will be useful when debugging specific issues related to
firmware HFI interface.

Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
---
 drivers/media/platform/qcom/venus/Makefile    |  2 +-
 drivers/media/platform/qcom/venus/core.c      |  3 +++
 drivers/media/platform/qcom/venus/core.h      |  3 +++
 drivers/media/platform/qcom/venus/dbgfs.c     | 21 +++++++++++++++++++
 drivers/media/platform/qcom/venus/dbgfs.h     | 12 +++++++++++
 drivers/media/platform/qcom/venus/hfi_venus.c |  7 ++++++-
 6 files changed, 46 insertions(+), 2 deletions(-)
 create mode 100644 drivers/media/platform/qcom/venus/dbgfs.c
 create mode 100644 drivers/media/platform/qcom/venus/dbgfs.h

diff --git a/drivers/media/platform/qcom/venus/Makefile b/drivers/media/platform/qcom/venus/Makefile
index 64af0bc1edae..dfc636865709 100644
--- a/drivers/media/platform/qcom/venus/Makefile
+++ b/drivers/media/platform/qcom/venus/Makefile
@@ -3,7 +3,7 @@
 
 venus-core-objs += core.o helpers.o firmware.o \
 		   hfi_venus.o hfi_msgs.o hfi_cmds.o hfi.o \
-		   hfi_parser.o pm_helpers.o
+		   hfi_parser.o pm_helpers.o dbgfs.o
 
 venus-dec-objs += vdec.o vdec_ctrls.o
 venus-enc-objs += venc.o venc_ctrls.o
diff --git a/drivers/media/platform/qcom/venus/core.c b/drivers/media/platform/qcom/venus/core.c
index 203c6538044f..249141e27fea 100644
--- a/drivers/media/platform/qcom/venus/core.c
+++ b/drivers/media/platform/qcom/venus/core.c
@@ -290,6 +290,8 @@ static int venus_probe(struct platform_device *pdev)
 	if (ret)
 		goto err_dev_unregister;
 
+	venus_dbgfs_init(core);
+
 	return 0;
 
 err_dev_unregister:
@@ -337,6 +339,7 @@ static int venus_remove(struct platform_device *pdev)
 	v4l2_device_unregister(&core->v4l2_dev);
 	mutex_destroy(&core->pm_lock);
 	mutex_destroy(&core->lock);
+	venus_dbgfs_deinit(core);
 
 	return ret;
 }
diff --git a/drivers/media/platform/qcom/venus/core.h b/drivers/media/platform/qcom/venus/core.h
index 7118612673c9..b48782f9aa95 100644
--- a/drivers/media/platform/qcom/venus/core.h
+++ b/drivers/media/platform/qcom/venus/core.h
@@ -12,6 +12,7 @@
 #include <media/v4l2-ctrls.h>
 #include <media/v4l2-device.h>
 
+#include "dbgfs.h"
 #include "hfi.h"
 
 #define VIDC_CLKS_NUM_MAX		4
@@ -136,6 +137,7 @@ struct venus_caps {
  * @priv:	a private filed for HFI operations
  * @ops:		the core HFI operations
  * @work:	a delayed work for handling system fatal error
+ * @root:	debugfs root directory
  */
 struct venus_core {
 	void __iomem *base;
@@ -185,6 +187,7 @@ struct venus_core {
 	unsigned int codecs_count;
 	unsigned int core0_usage_count;
 	unsigned int core1_usage_count;
+	struct dentry *root;
 };
 
 struct vdec_controls {
diff --git a/drivers/media/platform/qcom/venus/dbgfs.c b/drivers/media/platform/qcom/venus/dbgfs.c
new file mode 100644
index 000000000000..782d54ac1b8f
--- /dev/null
+++ b/drivers/media/platform/qcom/venus/dbgfs.c
@@ -0,0 +1,21 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2020 Linaro Ltd.
+ */
+
+#include <linux/debugfs.h>
+
+#include "core.h"
+
+extern int venus_fw_debug;
+
+void venus_dbgfs_init(struct venus_core *core)
+{
+	core->root = debugfs_create_dir("venus", NULL);
+	debugfs_create_x32("fw_level", 0644, core->root, &venus_fw_debug);
+}
+
+void venus_dbgfs_deinit(struct venus_core *core)
+{
+	debugfs_remove_recursive(core->root);
+}
diff --git a/drivers/media/platform/qcom/venus/dbgfs.h b/drivers/media/platform/qcom/venus/dbgfs.h
new file mode 100644
index 000000000000..b7b621a8472f
--- /dev/null
+++ b/drivers/media/platform/qcom/venus/dbgfs.h
@@ -0,0 +1,12 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* Copyright (C) 2020 Linaro Ltd. */
+
+#ifndef __VENUS_DBGFS_H__
+#define __VENUS_DBGFS_H__
+
+struct venus_core;
+
+void venus_dbgfs_init(struct venus_core *core);
+void venus_dbgfs_deinit(struct venus_core *core);
+
+#endif
diff --git a/drivers/media/platform/qcom/venus/hfi_venus.c b/drivers/media/platform/qcom/venus/hfi_venus.c
index 0d8855014ab3..3a04b08ab85a 100644
--- a/drivers/media/platform/qcom/venus/hfi_venus.c
+++ b/drivers/media/platform/qcom/venus/hfi_venus.c
@@ -130,7 +130,7 @@ struct venus_hfi_device {
 };
 
 static bool venus_pkt_debug;
-static int venus_fw_debug = HFI_DEBUG_MSG_ERROR | HFI_DEBUG_MSG_FATAL;
+int venus_fw_debug = HFI_DEBUG_MSG_ERROR | HFI_DEBUG_MSG_FATAL;
 static bool venus_sys_idle_indicator;
 static bool venus_fw_low_power_mode = true;
 static int venus_hw_rsp_timeout = 1000;
@@ -1130,9 +1130,14 @@ static int venus_session_init(struct venus_inst *inst, u32 session_type,
 			      u32 codec)
 {
 	struct venus_hfi_device *hdev = to_hfi_priv(inst->core);
+	struct device *dev = hdev->core->dev;
 	struct hfi_session_init_pkt pkt;
 	int ret;
 
+	ret = venus_sys_set_debug(hdev, venus_fw_debug);
+	if (ret)
+		dev_warn(dev, "setting fw debug msg ON failed (%d)\n", ret);
+
 	ret = pkt_session_init(&pkt, inst, session_type, codec);
 	if (ret)
 		goto err;
-- 
2.17.1

[PATCH v4 2/3] venus: Make debug infrastructure more flexible

[Stanimir Varbanov]

Here we introduce few debug macros with levels (low, medium and
high) and debug macro for firmware. Enabling the particular level
will be done by dynamic debug.

For example to enable debug messages with low level:
echo 'format "VENUSL" +p' > debugfs/dynamic_debug/control

If you want to enable all levels:
echo 'format "VENUS" +p' > debugfs/dynamic_debug/control

All the features which dynamic debugging provide are preserved.

And finaly all dev_dbg are translated to VDBGX with appropriate
debug levels.

Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
---
 drivers/media/platform/qcom/venus/core.h      |  5 ++
 drivers/media/platform/qcom/venus/helpers.c   |  2 +-
 drivers/media/platform/qcom/venus/hfi_msgs.c  | 30 ++++-----
 drivers/media/platform/qcom/venus/hfi_venus.c | 20 ++++--
 .../media/platform/qcom/venus/pm_helpers.c    |  3 +-
 drivers/media/platform/qcom/venus/vdec.c      | 63 +++++++++++++++++--
 drivers/media/platform/qcom/venus/venc.c      |  4 ++
 7 files changed, 96 insertions(+), 31 deletions(-)

diff --git a/drivers/media/platform/qcom/venus/core.h b/drivers/media/platform/qcom/venus/core.h
index b48782f9aa95..82438f19afba 100644
--- a/drivers/media/platform/qcom/venus/core.h
+++ b/drivers/media/platform/qcom/venus/core.h
@@ -15,6 +15,11 @@
 #include "dbgfs.h"
 #include "hfi.h"
 
+#define VDBGL(fmt, args...)	pr_debug("VENUSL: " fmt, ##args)
+#define VDBGM(fmt, args...)	pr_debug("VENUSM: " fmt, ##args)
+#define VDBGH(fmt, args...)	pr_debug("VENUSH: " fmt, ##args)
+#define VDBGFW(fmt, args...)	pr_debug("VENUSFW: " fmt, ##args)
+
 #define VIDC_CLKS_NUM_MAX		4
 #define VIDC_VCODEC_CLKS_NUM_MAX	2
 #define VIDC_PMDOMAINS_NUM_MAX		3
diff --git a/drivers/media/platform/qcom/venus/helpers.c b/drivers/media/platform/qcom/venus/helpers.c
index 0143af7822b2..115a9a2af1d6 100644
--- a/drivers/media/platform/qcom/venus/helpers.c
+++ b/drivers/media/platform/qcom/venus/helpers.c
@@ -396,7 +396,7 @@ put_ts_metadata(struct venus_inst *inst, struct vb2_v4l2_buffer *vbuf)
 	}
 
 	if (slot == -1) {
-		dev_dbg(inst->core->dev, "%s: no free slot\n", __func__);
+		VDBGH("no free slot for timestamp\n");
 		return;
 	}
 
diff --git a/drivers/media/platform/qcom/venus/hfi_msgs.c b/drivers/media/platform/qcom/venus/hfi_msgs.c
index 279a9d6fe737..36986d402c96 100644
--- a/drivers/media/platform/qcom/venus/hfi_msgs.c
+++ b/drivers/media/platform/qcom/venus/hfi_msgs.c
@@ -138,10 +138,9 @@ static void event_sys_error(struct venus_core *core, u32 event,
 			    struct hfi_msg_event_notify_pkt *pkt)
 {
 	if (pkt)
-		dev_dbg(core->dev,
-			"sys error (session id:%x, data1:%x, data2:%x)\n",
-			pkt->shdr.session_id, pkt->event_data1,
-			pkt->event_data2);
+		VDBGH("sys error (session id: %x, data1: %x, data2: %x)\n",
+		      pkt->shdr.session_id, pkt->event_data1,
+		      pkt->event_data2);
 
 	core->core_ops->event_notify(core, event);
 }
@@ -152,8 +151,8 @@ event_session_error(struct venus_core *core, struct venus_inst *inst,
 {
 	struct device *dev = core->dev;
 
-	dev_dbg(dev, "session error: event id:%x, session id:%x\n",
-		pkt->event_data1, pkt->shdr.session_id);
+	VDBGH("session error: event id: %x, session id: %x\n",
+	      pkt->event_data1, pkt->shdr.session_id);
 
 	if (!inst)
 		return;
@@ -236,8 +235,7 @@ static void hfi_sys_init_done(struct venus_core *core, struct venus_inst *inst,
 }
 
 static void
-sys_get_prop_image_version(struct device *dev,
-			   struct hfi_msg_sys_property_info_pkt *pkt)
+sys_get_prop_image_version(struct hfi_msg_sys_property_info_pkt *pkt)
 {
 	int req_bytes;
 
@@ -247,26 +245,25 @@ sys_get_prop_image_version(struct device *dev,
 		/* bad packet */
 		return;
 
-	dev_dbg(dev, "F/W version: %s\n", (u8 *)&pkt->data[1]);
+	VDBGL("F/W version: %s\n", (u8 *)&pkt->data[1]);
 }
 
 static void hfi_sys_property_info(struct venus_core *core,
 				  struct venus_inst *inst, void *packet)
 {
 	struct hfi_msg_sys_property_info_pkt *pkt = packet;
-	struct device *dev = core->dev;
 
 	if (!pkt->num_properties) {
-		dev_dbg(dev, "%s: no properties\n", __func__);
+		VDBGM("no properties\n");
 		return;
 	}
 
 	switch (pkt->data[0]) {
 	case HFI_PROPERTY_SYS_IMAGE_VERSION:
-		sys_get_prop_image_version(dev, pkt);
+		sys_get_prop_image_version(pkt);
 		break;
 	default:
-		dev_dbg(dev, "%s: unknown property data\n", __func__);
+		VDBGM("unknown property data\n");
 		break;
 	}
 }
@@ -297,7 +294,7 @@ static void hfi_sys_ping_done(struct venus_core *core, struct venus_inst *inst,
 static void hfi_sys_idle_done(struct venus_core *core, struct venus_inst *inst,
 			      void *packet)
 {
-	dev_dbg(core->dev, "sys idle\n");
+	VDBGL("sys idle\n");
 }
 
 static void hfi_sys_pc_prepare_done(struct venus_core *core,
@@ -305,7 +302,7 @@ static void hfi_sys_pc_prepare_done(struct venus_core *core,
 {
 	struct hfi_msg_sys_pc_prep_done_pkt *pkt = packet;
 
-	dev_dbg(core->dev, "pc prepare done (error %x)\n", pkt->error_type);
+	VDBGL("pc prepare done (error %x)\n", pkt->error_type);
 }
 
 static unsigned int
@@ -387,8 +384,7 @@ static void hfi_session_prop_info(struct venus_core *core,
 	case HFI_PROPERTY_CONFIG_VDEC_ENTROPY:
 		break;
 	default:
-		dev_dbg(dev, "%s: unknown property id:%x\n", __func__,
-			pkt->data[0]);
+		VDBGH("unknown property id: %x\n", pkt->data[0]);
 		return;
 	}
 
diff --git a/drivers/media/platform/qcom/venus/hfi_venus.c b/drivers/media/platform/qcom/venus/hfi_venus.c
index 3a04b08ab85a..9aef62f9b59a 100644
--- a/drivers/media/platform/qcom/venus/hfi_venus.c
+++ b/drivers/media/platform/qcom/venus/hfi_venus.c
@@ -467,7 +467,6 @@ static int venus_boot_core(struct venus_hfi_device *hdev)
 
 static u32 venus_hwversion(struct venus_hfi_device *hdev)
 {
-	struct device *dev = hdev->core->dev;
 	u32 ver = venus_readl(hdev, WRAPPER_HW_VERSION);
 	u32 major, minor, step;
 
@@ -477,7 +476,7 @@ static u32 venus_hwversion(struct venus_hfi_device *hdev)
 	minor = minor >> WRAPPER_HW_VERSION_MINOR_VERSION_SHIFT;
 	step = ver & WRAPPER_HW_VERSION_STEP_VERSION_MASK;
 
-	dev_dbg(dev, "venus hw version %x.%x.%x\n", major, minor, step);
+	VDBGL("venus hw version %x.%x.%x\n", major, minor, step);
 
 	return major;
 }
@@ -897,7 +896,6 @@ static int venus_session_cmd(struct venus_inst *inst, u32 pkt_type)
 
 static void venus_flush_debug_queue(struct venus_hfi_device *hdev)
 {
-	struct device *dev = hdev->core->dev;
 	void *packet = hdev->dbg_buf;
 
 	while (!venus_iface_dbgq_read(hdev, packet)) {
@@ -906,7 +904,7 @@ static void venus_flush_debug_queue(struct venus_hfi_device *hdev)
 		if (pkt->hdr.pkt_type != HFI_MSG_SYS_COV) {
 			struct hfi_msg_sys_debug_pkt *pkt = packet;
 
-			dev_dbg(dev, "%s", pkt->msg_data);
+			VDBGFW("%s", pkt->msg_data);
 		}
 	}
 }
@@ -1230,6 +1228,11 @@ static int venus_session_etb(struct venus_inst *inst,
 		ret = -EINVAL;
 	}
 
+	VDBGM("etb: %s: itag: %u, flen: %u, addr: %x\n",
+	      session_type == VIDC_SESSION_TYPE_DEC ? "dec" : "enc",
+	      in_frame->clnt_data, in_frame->filled_len,
+	      in_frame->device_addr);
+
 	return ret;
 }
 
@@ -1244,7 +1247,14 @@ static int venus_session_ftb(struct venus_inst *inst,
 	if (ret)
 		return ret;
 
-	return venus_iface_cmdq_write(hdev, &pkt);
+	ret = venus_iface_cmdq_write(hdev, &pkt);
+
+	VDBGM("ftb: %s: otag: %u, flen: %u, addr: %x\n",
+	      inst->session_type == VIDC_SESSION_TYPE_DEC ? "dec" : "enc",
+	      out_frame->clnt_data, out_frame->filled_len,
+	      out_frame->device_addr);
+
+	return ret;
 }
 
 static int venus_session_set_buffers(struct venus_inst *inst,
diff --git a/drivers/media/platform/qcom/venus/pm_helpers.c b/drivers/media/platform/qcom/venus/pm_helpers.c
index abf93158857b..ec7394615ef8 100644
--- a/drivers/media/platform/qcom/venus/pm_helpers.c
+++ b/drivers/media/platform/qcom/venus/pm_helpers.c
@@ -212,8 +212,7 @@ static int load_scale_bw(struct venus_core *core)
 	}
 	mutex_unlock(&core->lock);
 
-	dev_dbg(core->dev, "total: avg_bw: %u, peak_bw: %u\n",
-		total_avg, total_peak);
+	VDBGL("total: avg_bw: %u, peak_bw: %u\n", total_avg, total_peak);
 
 	return icc_set_bw(core->video_path, total_avg, total_peak);
 }
diff --git a/drivers/media/platform/qcom/venus/vdec.c b/drivers/media/platform/qcom/venus/vdec.c
index 7c4c483d5438..7959e452fbf3 100644
--- a/drivers/media/platform/qcom/venus/vdec.c
+++ b/drivers/media/platform/qcom/venus/vdec.c
@@ -225,7 +225,7 @@ static int vdec_check_src_change(struct venus_inst *inst)
 
 	if (!(inst->codec_state == VENUS_DEC_STATE_CAPTURE_SETUP) ||
 	    !inst->reconfig)
-		dev_dbg(inst->core->dev, "%s: wrong state\n", __func__);
+		VDBGM("wrong codec state %u\n", inst->codec_state);
 
 done:
 	return 0;
@@ -790,6 +790,10 @@ static int vdec_queue_setup(struct vb2_queue *q,
 	unsigned int in_num, out_num;
 	int ret = 0;
 
+	VDBGM("vb2: queue_setup: %s: begin (codec_state: %u)\n",
+	      V4L2_TYPE_IS_OUTPUT(q->type) ? "out" : "cap",
+	      inst->codec_state);
+
 	if (*num_planes) {
 		unsigned int output_buf_size = venus_helper_get_opb_size(inst);
 
@@ -859,6 +863,10 @@ static int vdec_queue_setup(struct vb2_queue *q,
 		break;
 	}
 
+	VDBGM("vb2: queue_setup: %s: end (codec_state: %u, ret: %d)\n",
+	      V4L2_TYPE_IS_OUTPUT(q->type) ? "out" : "cap",
+	      inst->codec_state, ret);
+
 	return ret;
 
 put_power:
@@ -897,6 +905,8 @@ static int vdec_start_capture(struct venus_inst *inst)
 {
 	int ret;
 
+	VDBGM("on: cap: begin (codec_state: %u)\n", inst->codec_state);
+
 	if (!inst->streamon_out)
 		return 0;
 
@@ -955,11 +965,16 @@ static int vdec_start_capture(struct venus_inst *inst)
 	inst->sequence_cap = 0;
 	inst->reconfig = false;
 
+	VDBGM("on: cap: end (codec_state: %u)\n", inst->codec_state);
+
 	return 0;
 
 free_dpb_bufs:
 	venus_helper_free_dpb_bufs(inst);
 err:
+	VDBGM("on: cap: end (codec_state: %u, ret: %d)\n",
+	      inst->codec_state, ret);
+
 	return ret;
 }
 
@@ -967,6 +982,8 @@ static int vdec_start_output(struct venus_inst *inst)
 {
 	int ret;
 
+	VDBGM("on: out: begin (codec_state: %u)\n", inst->codec_state);
+
 	if (inst->codec_state == VENUS_DEC_STATE_SEEK) {
 		ret = venus_helper_process_initial_out_bufs(inst);
 		inst->codec_state = VENUS_DEC_STATE_DECODING;
@@ -1015,6 +1032,10 @@ static int vdec_start_output(struct venus_inst *inst)
 
 done:
 	inst->streamon_out = 1;
+
+	VDBGM("on: out: end (codec_state: %u, ret: %d)\n",
+	      inst->codec_state, ret);
+
 	return ret;
 }
 
@@ -1069,6 +1090,8 @@ static int vdec_stop_capture(struct venus_inst *inst)
 {
 	int ret = 0;
 
+	VDBGM("off: cap: begin (codec_state: %u)\n", inst->codec_state);
+
 	switch (inst->codec_state) {
 	case VENUS_DEC_STATE_DECODING:
 		ret = hfi_session_flush(inst, HFI_FLUSH_ALL, true);
@@ -1090,6 +1113,9 @@ static int vdec_stop_capture(struct venus_inst *inst)
 
 	INIT_LIST_HEAD(&inst->registeredbufs);
 
+	VDBGM("off: cap: end (codec_state: %u, ret: %d)\n",
+	      inst->codec_state, ret);
+
 	return ret;
 }
 
@@ -1097,6 +1123,8 @@ static int vdec_stop_output(struct venus_inst *inst)
 {
 	int ret = 0;
 
+	VDBGM("off: out: begin (codec_state: %u)\n", inst->codec_state);
+
 	switch (inst->codec_state) {
 	case VENUS_DEC_STATE_DECODING:
 	case VENUS_DEC_STATE_DRAIN:
@@ -1112,6 +1140,9 @@ static int vdec_stop_output(struct venus_inst *inst)
 		break;
 	}
 
+	VDBGM("off: out: end (codec_state: %u, ret %d)\n",
+	      inst->codec_state, ret);
+
 	return ret;
 }
 
@@ -1146,6 +1177,8 @@ static void vdec_session_release(struct venus_inst *inst)
 	struct venus_core *core = inst->core;
 	int ret, abort = 0;
 
+	VDBGM("rel: begin (codec_state: %u)\n", inst->codec_state);
+
 	vdec_pm_get(inst);
 
 	mutex_lock(&inst->lock);
@@ -1175,15 +1208,23 @@ static void vdec_session_release(struct venus_inst *inst)
 
 	venus_pm_release_core(inst);
 	vdec_pm_put(inst, false);
+
+	VDBGM("rel: end (codec_state: %u)\n", inst->codec_state);
 }
 
 static int vdec_buf_init(struct vb2_buffer *vb)
 {
 	struct venus_inst *inst = vb2_get_drv_priv(vb->vb2_queue);
+	int ret;
 
 	inst->buf_count++;
 
-	return venus_helper_vb2_buf_init(vb);
+	ret = venus_helper_vb2_buf_init(vb);
+
+	VDBGM("vb2: buf_init: %s: done (codec_state: %u)\n",
+	      V4L2_TYPE_IS_OUTPUT(vb->type) ? "out" : "cap", inst->codec_state);
+
+	return ret;
 }
 
 static void vdec_buf_cleanup(struct vb2_buffer *vb)
@@ -1193,6 +1234,9 @@ static void vdec_buf_cleanup(struct vb2_buffer *vb)
 	inst->buf_count--;
 	if (!inst->buf_count)
 		vdec_session_release(inst);
+
+	VDBGM("vb2: buf_cleanup: %s: done (codec_state: %u)\n",
+	      V4L2_TYPE_IS_OUTPUT(vb->type) ? "out" : "cap", inst->codec_state);
 }
 
 static void vdec_vb2_buf_queue(struct vb2_buffer *vb)
@@ -1281,6 +1325,10 @@ static void vdec_buf_done(struct venus_inst *inst, unsigned int buf_type,
 	}
 
 	v4l2_m2m_buf_done(vbuf, state);
+
+	VDBGH("done: %s, idx: %02u, flen: %08u, flags: hfi: %08x, v4l2: %08x\n",
+	      V4L2_TYPE_IS_OUTPUT(type) ? "out" : "cap",
+	      vbuf->vb2_buf.index, bytesused, hfi_flags, vbuf->flags);
 }
 
 static void vdec_event_change(struct venus_inst *inst,
@@ -1289,7 +1337,6 @@ static void vdec_event_change(struct venus_inst *inst,
 	static const struct v4l2_event ev = {
 		.type = V4L2_EVENT_SOURCE_CHANGE,
 		.u.src_change.changes = V4L2_EVENT_SRC_CH_RESOLUTION };
-	struct device *dev = inst->core->dev_dec;
 	struct v4l2_format format = {};
 
 	mutex_lock(&inst->lock);
@@ -1310,8 +1357,12 @@ static void vdec_event_change(struct venus_inst *inst,
 	if (inst->bit_depth != ev_data->bit_depth)
 		inst->bit_depth = ev_data->bit_depth;
 
-	dev_dbg(dev, "event %s sufficient resources (%ux%u)\n",
-		sufficient ? "" : "not", ev_data->width, ev_data->height);
+	VDBGH("event: %s sufficient resources (%ux%u)\n",
+	      sufficient ? "" : "not", ev_data->width, ev_data->height);
+
+	if (ev_data->buf_count)
+		VDBGH("event: buf_count: %u, old: %u\n",
+		      ev_data->buf_count, inst->num_output_bufs);
 
 	if (sufficient) {
 		hfi_session_continue(inst);
@@ -1344,7 +1395,7 @@ static void vdec_event_change(struct venus_inst *inst,
 
 		ret = hfi_session_flush(inst, HFI_FLUSH_OUTPUT, false);
 		if (ret)
-			dev_dbg(dev, "flush output error %d\n", ret);
+			VDBGH("flush output error (%d)\n", ret);
 	}
 
 	inst->reconfig = true;
diff --git a/drivers/media/platform/qcom/venus/venc.c b/drivers/media/platform/qcom/venus/venc.c
index feed648550d1..c591d00ee0a7 100644
--- a/drivers/media/platform/qcom/venus/venc.c
+++ b/drivers/media/platform/qcom/venus/venc.c
@@ -1074,6 +1074,10 @@ static void venc_buf_done(struct venus_inst *inst, unsigned int buf_type,
 	}
 
 	v4l2_m2m_buf_done(vbuf, VB2_BUF_STATE_DONE);
+
+	VDBGH("done: %s, idx: %02u, flen: %08u, flags: hfi: %08x, v4l2: %08x\n",
+	      V4L2_TYPE_IS_OUTPUT(type) ? "out" : "cap",
+	      vbuf->vb2_buf.index, bytesused, hfi_flags, vbuf->flags);
 }
 
 static void venc_event_notify(struct venus_inst *inst, u32 event,
-- 
2.17.1

[PATCH v4 3/3] venus: Add a debugfs file for SSR trigger

[Stanimir Varbanov]

The SSR (SubSystem Restart) is used to simulate an error on FW
side of Venus. We support following type of triggers - fatal error,
div by zero and watchdog IRQ.

Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
---
 drivers/media/platform/qcom/venus/dbgfs.c | 30 +++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/drivers/media/platform/qcom/venus/dbgfs.c b/drivers/media/platform/qcom/venus/dbgfs.c
index 782d54ac1b8f..f95b7b1febe5 100644
--- a/drivers/media/platform/qcom/venus/dbgfs.c
+++ b/drivers/media/platform/qcom/venus/dbgfs.c
@@ -9,10 +9,40 @@
 
 extern int venus_fw_debug;
 
+static int trigger_ssr_open(struct inode *inode, struct file *file)
+{
+	file->private_data = inode->i_private;
+	return 0;
+}
+
+static ssize_t trigger_ssr_write(struct file *filp, const char __user *buf,
+				 size_t count, loff_t *ppos)
+{
+	struct venus_core *core = filp->private_data;
+	u32 ssr_type;
+	int ret;
+
+	ret = kstrtou32_from_user(buf, count, 4, &ssr_type);
+	if (ret)
+		return ret;
+
+	ret = hfi_core_trigger_ssr(core, ssr_type);
+	if (ret < 0)
+		return ret;
+
+	return count;
+}
+
+static const struct file_operations ssr_fops = {
+	.open = trigger_ssr_open,
+	.write = trigger_ssr_write,
+};
+
 void venus_dbgfs_init(struct venus_core *core)
 {
 	core->root = debugfs_create_dir("venus", NULL);
 	debugfs_create_x32("fw_level", 0644, core->root, &venus_fw_debug);
+	debugfs_create_file("trigger_ssr", 0200, core->root, core, &ssr_fops);
 }
 
 void venus_dbgfs_deinit(struct venus_core *core)
-- 
2.17.1

Re: [PATCH v4 1/3] venus: Add debugfs interface to set firmware log level

[Greg KH]

On Sun, Jun 14, 2020 at 01:39:17AM +0300, Stanimir Varbanov wrote:
> This will be useful when debugging specific issues related to
> firmware HFI interface.
> 
> Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>

You didn't cc: any of us on the patchs, like you did on 0/3 :(


> ---
>  drivers/media/platform/qcom/venus/Makefile    |  2 +-
>  drivers/media/platform/qcom/venus/core.c      |  3 +++
>  drivers/media/platform/qcom/venus/core.h      |  3 +++
>  drivers/media/platform/qcom/venus/dbgfs.c     | 21 +++++++++++++++++++
>  drivers/media/platform/qcom/venus/dbgfs.h     | 12 +++++++++++
>  drivers/media/platform/qcom/venus/hfi_venus.c |  7 ++++++-
>  6 files changed, 46 insertions(+), 2 deletions(-)
>  create mode 100644 drivers/media/platform/qcom/venus/dbgfs.c
>  create mode 100644 drivers/media/platform/qcom/venus/dbgfs.h
> 
> diff --git a/drivers/media/platform/qcom/venus/Makefile b/drivers/media/platform/qcom/venus/Makefile
> index 64af0bc1edae..dfc636865709 100644
> --- a/drivers/media/platform/qcom/venus/Makefile
> +++ b/drivers/media/platform/qcom/venus/Makefile
> @@ -3,7 +3,7 @@
>  
>  venus-core-objs += core.o helpers.o firmware.o \
>  		   hfi_venus.o hfi_msgs.o hfi_cmds.o hfi.o \
> -		   hfi_parser.o pm_helpers.o
> +		   hfi_parser.o pm_helpers.o dbgfs.o
>  
>  venus-dec-objs += vdec.o vdec_ctrls.o
>  venus-enc-objs += venc.o venc_ctrls.o
> diff --git a/drivers/media/platform/qcom/venus/core.c b/drivers/media/platform/qcom/venus/core.c
> index 203c6538044f..249141e27fea 100644
> --- a/drivers/media/platform/qcom/venus/core.c
> +++ b/drivers/media/platform/qcom/venus/core.c
> @@ -290,6 +290,8 @@ static int venus_probe(struct platform_device *pdev)
>  	if (ret)
>  		goto err_dev_unregister;
>  
> +	venus_dbgfs_init(core);
> +
>  	return 0;
>  
>  err_dev_unregister:
> @@ -337,6 +339,7 @@ static int venus_remove(struct platform_device *pdev)
>  	v4l2_device_unregister(&core->v4l2_dev);
>  	mutex_destroy(&core->pm_lock);
>  	mutex_destroy(&core->lock);
> +	venus_dbgfs_deinit(core);
>  
>  	return ret;
>  }
> diff --git a/drivers/media/platform/qcom/venus/core.h b/drivers/media/platform/qcom/venus/core.h
> index 7118612673c9..b48782f9aa95 100644
> --- a/drivers/media/platform/qcom/venus/core.h
> +++ b/drivers/media/platform/qcom/venus/core.h
> @@ -12,6 +12,7 @@
>  #include <media/v4l2-ctrls.h>
>  #include <media/v4l2-device.h>
>  
> +#include "dbgfs.h"
>  #include "hfi.h"
>  
>  #define VIDC_CLKS_NUM_MAX		4
> @@ -136,6 +137,7 @@ struct venus_caps {
>   * @priv:	a private filed for HFI operations
>   * @ops:		the core HFI operations
>   * @work:	a delayed work for handling system fatal error
> + * @root:	debugfs root directory
>   */
>  struct venus_core {
>  	void __iomem *base;
> @@ -185,6 +187,7 @@ struct venus_core {
>  	unsigned int codecs_count;
>  	unsigned int core0_usage_count;
>  	unsigned int core1_usage_count;
> +	struct dentry *root;
>  };
>  
>  struct vdec_controls {
> diff --git a/drivers/media/platform/qcom/venus/dbgfs.c b/drivers/media/platform/qcom/venus/dbgfs.c
> new file mode 100644
> index 000000000000..782d54ac1b8f
> --- /dev/null
> +++ b/drivers/media/platform/qcom/venus/dbgfs.c
> @@ -0,0 +1,21 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2020 Linaro Ltd.
> + */
> +
> +#include <linux/debugfs.h>
> +
> +#include "core.h"
> +
> +extern int venus_fw_debug;
> +
> +void venus_dbgfs_init(struct venus_core *core)
> +{
> +	core->root = debugfs_create_dir("venus", NULL);
> +	debugfs_create_x32("fw_level", 0644, core->root, &venus_fw_debug);
> +}
> +
> +void venus_dbgfs_deinit(struct venus_core *core)
> +{
> +	debugfs_remove_recursive(core->root);
> +}
> diff --git a/drivers/media/platform/qcom/venus/dbgfs.h b/drivers/media/platform/qcom/venus/dbgfs.h
> new file mode 100644
> index 000000000000..b7b621a8472f
> --- /dev/null
> +++ b/drivers/media/platform/qcom/venus/dbgfs.h
> @@ -0,0 +1,12 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/* Copyright (C) 2020 Linaro Ltd. */
> +
> +#ifndef __VENUS_DBGFS_H__
> +#define __VENUS_DBGFS_H__
> +
> +struct venus_core;
> +
> +void venus_dbgfs_init(struct venus_core *core);
> +void venus_dbgfs_deinit(struct venus_core *core);
> +
> +#endif
> diff --git a/drivers/media/platform/qcom/venus/hfi_venus.c b/drivers/media/platform/qcom/venus/hfi_venus.c
> index 0d8855014ab3..3a04b08ab85a 100644
> --- a/drivers/media/platform/qcom/venus/hfi_venus.c
> +++ b/drivers/media/platform/qcom/venus/hfi_venus.c
> @@ -130,7 +130,7 @@ struct venus_hfi_device {
>  };
>  
>  static bool venus_pkt_debug;
> -static int venus_fw_debug = HFI_DEBUG_MSG_ERROR | HFI_DEBUG_MSG_FATAL;
> +int venus_fw_debug = HFI_DEBUG_MSG_ERROR | HFI_DEBUG_MSG_FATAL;
>  static bool venus_sys_idle_indicator;
>  static bool venus_fw_low_power_mode = true;
>  static int venus_hw_rsp_timeout = 1000;
> @@ -1130,9 +1130,14 @@ static int venus_session_init(struct venus_inst *inst, u32 session_type,
>  			      u32 codec)
>  {
>  	struct venus_hfi_device *hdev = to_hfi_priv(inst->core);
> +	struct device *dev = hdev->core->dev;
>  	struct hfi_session_init_pkt pkt;
>  	int ret;
>  
> +	ret = venus_sys_set_debug(hdev, venus_fw_debug);
> +	if (ret)
> +		dev_warn(dev, "setting fw debug msg ON failed (%d)\n", ret);

Why do you care about this to tell the user about it?

thanks,

greg k-h

Re: [PATCH v4 2/3] venus: Make debug infrastructure more flexible

[Greg KH]

On Sun, Jun 14, 2020 at 01:39:18AM +0300, Stanimir Varbanov wrote:
>  	if (slot == -1) {
> -		dev_dbg(inst->core->dev, "%s: no free slot\n", __func__);
> +		VDBGH("no free slot for timestamp\n");

Again, no, you just lost a lot of valuable information by changing to a
different format (like driver, specific device, etc.).  Please don't do
this, it just makes the information less than before.

thanks,

greg k-h

Re: [PATCH v4 2/3] venus: Make debug infrastructure more flexible

[Stanimir Varbanov]

Hi Greg,

On 6/14/20 9:37 AM, Greg KH wrote:
> On Sun, Jun 14, 2020 at 01:39:18AM +0300, Stanimir Varbanov wrote:
>>  	if (slot == -1) {
>> -		dev_dbg(inst->core->dev, "%s: no free slot\n", __func__);
>> +		VDBGH("no free slot for timestamp\n");
> 
> Again, no, you just lost a lot of valuable information by changing to a
> different format (like driver, specific device, etc.).  Please don't do
> this, it just makes the information less than before.

OK, one of the reasons to use pr_debug inside VDBGH macro is to avoid
having struct device *dev variable in every function with dev_dbg even
when the function doesn't use it.

Are you fine with s/pr_debug/dev_dbg in VDBGX macros?

-- 
regards,
Stan

Re: [PATCH v4 1/3] venus: Add debugfs interface to set firmware log level

[Stanimir Varbanov]

Hi Greg,

On 6/14/20 9:35 AM, Greg KH wrote:
> On Sun, Jun 14, 2020 at 01:39:17AM +0300, Stanimir Varbanov wrote:
>> This will be useful when debugging specific issues related to
>> firmware HFI interface.
>>
>> Signed-off-by: Stanimir Varbanov <stanimir.varbanov@linaro.org>
> 
> You didn't cc: any of us on the patchs, like you did on 0/3 :(

yes, sorry about that.

> 
> 
>> ---
>>  drivers/media/platform/qcom/venus/Makefile    |  2 +-
>>  drivers/media/platform/qcom/venus/core.c      |  3 +++
>>  drivers/media/platform/qcom/venus/core.h      |  3 +++
>>  drivers/media/platform/qcom/venus/dbgfs.c     | 21 +++++++++++++++++++
>>  drivers/media/platform/qcom/venus/dbgfs.h     | 12 +++++++++++
>>  drivers/media/platform/qcom/venus/hfi_venus.c |  7 ++++++-
>>  6 files changed, 46 insertions(+), 2 deletions(-)
>>  create mode 100644 drivers/media/platform/qcom/venus/dbgfs.c
>>  create mode 100644 drivers/media/platform/qcom/venus/dbgfs.h
>>
>> diff --git a/drivers/media/platform/qcom/venus/Makefile b/drivers/media/platform/qcom/venus/Makefile
>> index 64af0bc1edae..dfc636865709 100644
>> --- a/drivers/media/platform/qcom/venus/Makefile
>> +++ b/drivers/media/platform/qcom/venus/Makefile
>> @@ -3,7 +3,7 @@
>>  
>>  venus-core-objs += core.o helpers.o firmware.o \
>>  		   hfi_venus.o hfi_msgs.o hfi_cmds.o hfi.o \
>> -		   hfi_parser.o pm_helpers.o
>> +		   hfi_parser.o pm_helpers.o dbgfs.o
>>  
>>  venus-dec-objs += vdec.o vdec_ctrls.o
>>  venus-enc-objs += venc.o venc_ctrls.o
>> diff --git a/drivers/media/platform/qcom/venus/core.c b/drivers/media/platform/qcom/venus/core.c
>> index 203c6538044f..249141e27fea 100644
>> --- a/drivers/media/platform/qcom/venus/core.c
>> +++ b/drivers/media/platform/qcom/venus/core.c
>> @@ -290,6 +290,8 @@ static int venus_probe(struct platform_device *pdev)
>>  	if (ret)
>>  		goto err_dev_unregister;
>>  
>> +	venus_dbgfs_init(core);
>> +
>>  	return 0;
>>  
>>  err_dev_unregister:
>> @@ -337,6 +339,7 @@ static int venus_remove(struct platform_device *pdev)
>>  	v4l2_device_unregister(&core->v4l2_dev);
>>  	mutex_destroy(&core->pm_lock);
>>  	mutex_destroy(&core->lock);
>> +	venus_dbgfs_deinit(core);
>>  
>>  	return ret;
>>  }
>> diff --git a/drivers/media/platform/qcom/venus/core.h b/drivers/media/platform/qcom/venus/core.h
>> index 7118612673c9..b48782f9aa95 100644
>> --- a/drivers/media/platform/qcom/venus/core.h
>> +++ b/drivers/media/platform/qcom/venus/core.h
>> @@ -12,6 +12,7 @@
>>  #include <media/v4l2-ctrls.h>
>>  #include <media/v4l2-device.h>
>>  
>> +#include "dbgfs.h"
>>  #include "hfi.h"
>>  
>>  #define VIDC_CLKS_NUM_MAX		4
>> @@ -136,6 +137,7 @@ struct venus_caps {
>>   * @priv:	a private filed for HFI operations
>>   * @ops:		the core HFI operations
>>   * @work:	a delayed work for handling system fatal error
>> + * @root:	debugfs root directory
>>   */
>>  struct venus_core {
>>  	void __iomem *base;
>> @@ -185,6 +187,7 @@ struct venus_core {
>>  	unsigned int codecs_count;
>>  	unsigned int core0_usage_count;
>>  	unsigned int core1_usage_count;
>> +	struct dentry *root;
>>  };
>>  
>>  struct vdec_controls {
>> diff --git a/drivers/media/platform/qcom/venus/dbgfs.c b/drivers/media/platform/qcom/venus/dbgfs.c
>> new file mode 100644
>> index 000000000000..782d54ac1b8f
>> --- /dev/null
>> +++ b/drivers/media/platform/qcom/venus/dbgfs.c
>> @@ -0,0 +1,21 @@
>> +// SPDX-License-Identifier: GPL-2.0-only
>> +/*
>> + * Copyright (C) 2020 Linaro Ltd.
>> + */
>> +
>> +#include <linux/debugfs.h>
>> +
>> +#include "core.h"
>> +
>> +extern int venus_fw_debug;
>> +
>> +void venus_dbgfs_init(struct venus_core *core)
>> +{
>> +	core->root = debugfs_create_dir("venus", NULL);
>> +	debugfs_create_x32("fw_level", 0644, core->root, &venus_fw_debug);
>> +}
>> +
>> +void venus_dbgfs_deinit(struct venus_core *core)
>> +{
>> +	debugfs_remove_recursive(core->root);
>> +}
>> diff --git a/drivers/media/platform/qcom/venus/dbgfs.h b/drivers/media/platform/qcom/venus/dbgfs.h
>> new file mode 100644
>> index 000000000000..b7b621a8472f
>> --- /dev/null
>> +++ b/drivers/media/platform/qcom/venus/dbgfs.h
>> @@ -0,0 +1,12 @@
>> +/* SPDX-License-Identifier: GPL-2.0 */
>> +/* Copyright (C) 2020 Linaro Ltd. */
>> +
>> +#ifndef __VENUS_DBGFS_H__
>> +#define __VENUS_DBGFS_H__
>> +
>> +struct venus_core;
>> +
>> +void venus_dbgfs_init(struct venus_core *core);
>> +void venus_dbgfs_deinit(struct venus_core *core);
>> +
>> +#endif
>> diff --git a/drivers/media/platform/qcom/venus/hfi_venus.c b/drivers/media/platform/qcom/venus/hfi_venus.c
>> index 0d8855014ab3..3a04b08ab85a 100644
>> --- a/drivers/media/platform/qcom/venus/hfi_venus.c
>> +++ b/drivers/media/platform/qcom/venus/hfi_venus.c
>> @@ -130,7 +130,7 @@ struct venus_hfi_device {
>>  };
>>  
>>  static bool venus_pkt_debug;
>> -static int venus_fw_debug = HFI_DEBUG_MSG_ERROR | HFI_DEBUG_MSG_FATAL;
>> +int venus_fw_debug = HFI_DEBUG_MSG_ERROR | HFI_DEBUG_MSG_FATAL;
>>  static bool venus_sys_idle_indicator;
>>  static bool venus_fw_low_power_mode = true;
>>  static int venus_hw_rsp_timeout = 1000;
>> @@ -1130,9 +1130,14 @@ static int venus_session_init(struct venus_inst *inst, u32 session_type,
>>  			      u32 codec)
>>  {
>>  	struct venus_hfi_device *hdev = to_hfi_priv(inst->core);
>> +	struct device *dev = hdev->core->dev;
>>  	struct hfi_session_init_pkt pkt;
>>  	int ret;
>>  
>> +	ret = venus_sys_set_debug(hdev, venus_fw_debug);
>> +	if (ret)
>> +		dev_warn(dev, "setting fw debug msg ON failed (%d)\n", ret);
> 
> Why do you care about this to tell the user about it?

I already answered to this question in previous patchset version. I'll
drop the message and return an error if set_debug fail.

> 
> thanks,
> 
> greg k-h
> 

-- 
regards,
Stan

Re: [PATCH v4 2/3] venus: Make debug infrastructure more flexible

[Greg KH]

On Mon, Jun 15, 2020 at 12:55:29PM +0300, Stanimir Varbanov wrote:
> Hi Greg,
> 
> On 6/14/20 9:37 AM, Greg KH wrote:
> > On Sun, Jun 14, 2020 at 01:39:18AM +0300, Stanimir Varbanov wrote:
> >>  	if (slot == -1) {
> >> -		dev_dbg(inst->core->dev, "%s: no free slot\n", __func__);
> >> +		VDBGH("no free slot for timestamp\n");
> > 
> > Again, no, you just lost a lot of valuable information by changing to a
> > different format (like driver, specific device, etc.).  Please don't do
> > this, it just makes the information less than before.
> 
> OK, one of the reasons to use pr_debug inside VDBGH macro is to avoid
> having struct device *dev variable in every function with dev_dbg even
> when the function doesn't use it.

But the function _is_ using it, as you are referring to the device that
is being controlled by the driver.  That's the point, you are stripping
off that very valuable information for no reason.

Which means to me that you never really actually _NEED_ these debugging
messages, as you have not used them to see if it provides you with
something that can tell you something about something.

So, let me push harder, why do you even want this message at all?  What
can it provide you now that the driver is up and working properly?

> Are you fine with s/pr_debug/dev_dbg in VDBGX macros?

I would be a bit happier yes, but the fact that you didn't use it means
you aren't even looking at these messages, which implies that it isn't
even needed.

So, how about just stripping all of these debugging messages out
entirely?  What do they provide that you don't already know?  Who would
use them?

thanks,

greg k-h

Re: [PATCH v4 2/3] venus: Make debug infrastructure more flexible

[Stanimir Varbanov]

Hi Greg,

On 6/15/20 3:03 PM, Greg KH wrote:
> On Mon, Jun 15, 2020 at 12:55:29PM +0300, Stanimir Varbanov wrote:
>> Hi Greg,
>>
>> On 6/14/20 9:37 AM, Greg KH wrote:
>>> On Sun, Jun 14, 2020 at 01:39:18AM +0300, Stanimir Varbanov wrote:
>>>>  	if (slot == -1) {
>>>> -		dev_dbg(inst->core->dev, "%s: no free slot\n", __func__);
>>>> +		VDBGH("no free slot for timestamp\n");
>>>
>>> Again, no, you just lost a lot of valuable information by changing to a
>>> different format (like driver, specific device, etc.).  Please don't do
>>> this, it just makes the information less than before.
>>
>> OK, one of the reasons to use pr_debug inside VDBGH macro is to avoid
>> having struct device *dev variable in every function with dev_dbg even
>> when the function doesn't use it.
> 
> But the function _is_ using it, as you are referring to the device that
> is being controlled by the driver.  That's the point, you are stripping
> off that very valuable information for no git grep dev_dbg | wc -lreason.
> 
> Which means to me that you never really actually _NEED_ these debugging
> messages, as you have not used them to see if it provides you with
> something that can tell you something about something.
> 
> So, let me push harder, why do you even want this message at all?  What
> can it provide you now that the driver is up and working properly?

I will delete that message.

> 
>> Are you fine with s/pr_debug/dev_dbg in VDBGX macros?
> 
> I would be a bit happier yes, but the fact that you didn't use it means
> you aren't even looking at these messages, which implies that it isn't
> even needed.
> 
> So, how about just stripping all of these debugging messages out

I'm not sure for which messages you are talking. The messages added by
this patch or the messages which currently exist?

> entirely?  What do they provide that you don't already know?  Who would
> use them?

Presently in 5.8-rc1 debug messages count for similar (encoder/decoder)
drivers compared with Venus one:

Venus
$git grep dev_dbg | wc -l
15

Coda
$git grep coda_dbg | wc -l
56

Mtk-vcodec
$git grep mtk_v4l2_debug | wc -l
95

Mfc
$git grep mfc_debug | wc -l
227

As you can see Venus driver is the one with smallest count of debug
messages. It is smallest because I also don't want to overload the code
with so many debugs and thus make it unreadable.

I personally don't need so much debug messages. I can add them to debug
some particular issue and drop them before sending the fix. But now when
the driver is going to be used more widely I've been asked to "improve"
debug infrastructure. That will help to unfamiliar with the driver
persons to enable debug messages and send bug reports to help them to
diagnose the problem.

What messages are needed and where is a subjective question. I'm relying
on my experience with the driver and issues I had previously.

> 
> thanks,
> 
> greg k-h
> 

-- 
regards,
Stan