[Intel-gfx] [PATCH 08/14] drm/i915: Debugfs support for GuC logging control

[akash.goel at intel.com]

From: Sagar Arun Kamble <sagar.a.kamble at intel.com>

This patch provides debugfs interface i915_guc_output_control for
on the fly enabling/disabling of logging in GuC firmware and controlling
the verbosity level of logs.
The value written to the file, should have bit 0 set to enable logging and
bits 4-7 should contain the verbosity info.

v2: Add a forceful flush, to collect left over logs, on disabling logging.
    Useful for Validation.

Signed-off-by: Sagar Arun Kamble <sagar.a.kamble at intel.com>
Signed-off-by: Akash Goel <akash.goel at intel.com>
---
 drivers/gpu/drm/i915/i915_debugfs.c        | 32 ++++++++++++++++-
 drivers/gpu/drm/i915/i915_guc_submission.c | 57 ++++++++++++++++++++++++++++++
 drivers/gpu/drm/i915/intel_guc.h           |  1 +
 3 files changed, 89 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index de197535..16aeab2 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -2648,6 +2648,35 @@ static int i915_guc_log_dump(struct seq_file *m, void *data)
 	return 0;
 }
 
+static int
+i915_guc_log_control_set(void *data, u64 val)
+{
+	struct drm_device *dev = data;
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	int ret;
+
+	ret = mutex_lock_interruptible(&dev->struct_mutex);
+	if (ret)
+		return ret;
+
+	if (!i915.enable_guc_submission || !dev_priv->guc.log.obj) {
+		ret = -EINVAL;
+		goto end;
+	}
+
+	intel_runtime_pm_get(dev_priv);
+	ret = i915_guc_log_control(dev, val);
+	intel_runtime_pm_put(dev_priv);
+
+end:
+	mutex_unlock(&dev->struct_mutex);
+	return ret;
+}
+
+DEFINE_SIMPLE_ATTRIBUTE(i915_guc_log_control_fops,
+			NULL, i915_guc_log_control_set,
+			"0x%08llx\n");
+
 static int i915_edp_psr_status(struct seq_file *m, void *data)
 {
 	struct drm_info_node *node = m->private;
@@ -5510,7 +5539,8 @@ static const struct i915_debugfs_files {
 	{"i915_fbc_false_color", &i915_fbc_fc_fops},
 	{"i915_dp_test_data", &i915_displayport_test_data_fops},
 	{"i915_dp_test_type", &i915_displayport_test_type_fops},
-	{"i915_dp_test_active", &i915_displayport_test_active_fops}
+	{"i915_dp_test_active", &i915_displayport_test_active_fops},
+	{"i915_guc_log_control", &i915_guc_log_control_fops}
 };
 
 void intel_display_crc_init(struct drm_device *dev)
diff --git a/drivers/gpu/drm/i915/i915_guc_submission.c b/drivers/gpu/drm/i915/i915_guc_submission.c
index 86c2381..5b44976 100644
--- a/drivers/gpu/drm/i915/i915_guc_submission.c
+++ b/drivers/gpu/drm/i915/i915_guc_submission.c
@@ -187,6 +187,16 @@ static int host2guc_force_logbuffer_flush(struct intel_guc *guc)
 	return host2guc_action(guc, data, 2);
 }
 
+static int host2guc_logging_control(struct intel_guc *guc, u32 control_val)
+{
+	u32 data[2];
+
+	data[0] = HOST2GUC_ACTION_UK_LOG_ENABLE_LOGGING;
+	data[1] = control_val;
+
+	return host2guc_action(guc, data, 2);
+}
+
 /*
  * Initialise, update, or clear doorbell data shared with the GuC
  *
@@ -1374,3 +1384,50 @@ void i915_guc_register(struct drm_device *dev)
 	guc_log_late_setup(dev);
 	mutex_unlock(&dev->struct_mutex);
 }
+
+int i915_guc_log_control(struct drm_device *dev, uint64_t control_val)
+{
+	struct drm_i915_private *dev_priv = dev->dev_private;
+	union guc_log_control log_param;
+	int ret;
+
+	log_param.logging_enabled = control_val & 0x1;
+	log_param.verbosity = (control_val >> 4) & 0xF;
+
+	if (log_param.verbosity < GUC_LOG_VERBOSITY_MIN ||
+	    log_param.verbosity > GUC_LOG_VERBOSITY_MAX)
+		return -EINVAL;
+
+	/* This combination doesn't make sense & won't have any effect */
+	if (!log_param.logging_enabled && (i915.guc_log_level < 0))
+		return -EINVAL;
+
+	ret = host2guc_logging_control(&dev_priv->guc, log_param.value);
+	if (ret < 0) {
+		DRM_DEBUG_DRIVER("host2guc action failed\n");
+		return ret;
+	}
+
+	i915.guc_log_level = log_param.verbosity;
+
+	/* If log_level was set as -1 at boot time, then the relay channel file
+	 * wouldn't have been created by now and interrupts also would not have
+	 * been enabled.
+	 */
+	if (!dev_priv->guc.log.relay_chan) {
+		ret = guc_log_late_setup(dev_priv->dev);
+		if (!ret)
+			gen9_enable_guc_interrupts(dev_priv);
+	} else if (!log_param.logging_enabled) {
+		/* Once logging is disabled, GuC won't generate logs & send an
+		 * interrupt. But there could be some data in the log buffer
+		 * which is yet to be captured. So request GuC to update the log
+		 * buffer state and send the flush interrupt so that Host can
+		 * collect the left over logs also.
+		 */
+		flush_work(&dev_priv->guc.events_work);
+		host2guc_force_logbuffer_flush(&dev_priv->guc);
+	}
+
+	return ret;
+}
diff --git a/drivers/gpu/drm/i915/intel_guc.h b/drivers/gpu/drm/i915/intel_guc.h
index 445c9e8..3e90279 100644
--- a/drivers/gpu/drm/i915/intel_guc.h
+++ b/drivers/gpu/drm/i915/intel_guc.h
@@ -177,5 +177,6 @@ void i915_guc_capture_logs(struct drm_device *dev, bool capture_all);
 void i915_guc_capture_logs_on_reset(struct drm_device *dev);
 void i915_guc_register(struct drm_device *dev);
 void i915_guc_unregister(struct drm_device *dev);
+int i915_guc_log_control(struct drm_device *dev, uint64_t control_val);
 
 #endif
-- 
1.9.2