[PATCH i-g-t 1/6] lib/igt_kms: add DP link management helper functions
Kunal Joshi
kunal1.joshi at intel.com
Thu Sep 12 06:28:34 UTC 2024
Added helper functions for below
- read current/max link_rate/lane_count
- forcing link retraining
- forcing link training failures
- read pending retrain
- read pending link training failures
- checking output supports forcing lt failures
- force link_rate/lane_count
v2: combine all link training debugfs in one patch (Imre)
remove unwanted valid output check (Imre)
return link_rate/lane_count marked with '*' or an error (Imre)
Signed-off-by: Kunal Joshi <kunal1.joshi at intel.com>
---
lib/igt_kms.c | 210 ++++++++++++++++++++++++++++++++++++++++++++++++++
lib/igt_kms.h | 10 +++
2 files changed, 220 insertions(+)
diff --git a/lib/igt_kms.c b/lib/igt_kms.c
index dd530dbab..f0ac1e5dc 100644
--- a/lib/igt_kms.c
+++ b/lib/igt_kms.c
@@ -61,6 +61,7 @@
#include "sw_sync.h"
#ifdef HAVE_CHAMELIUM
#include "igt_chamelium.h"
+#include <ctype.h>
#endif
/**
@@ -6705,3 +6706,212 @@ int get_num_scalers(igt_display_t *display, enum pipe pipe)
return num_scalers;
}
+
+/**
+ * igt_get_dp_link_param_set_for_output:
+ * @drm_fd: A drm file descriptor
+ * @output: Target output
+ * @link_param: 0 for lane count, 1 for link rate
+ *
+ * Returns: link_rate / lane_count if set for output else -1
+ */
+int igt_get_dp_link_param_set_for_output(int drm_fd, igt_output_t *output, int link_param)
+{
+ char *star_ptr, *param_ptr;
+ char buf[512];
+ int dir, res;
+ int ret;
+
+ ret = -1;
+ dir = igt_debugfs_connector_dir(drm_fd, output->name, O_RDONLY);
+ igt_assert_f(dir >= 0, "Failed to open debugfs dir for connector %s\n",
+ igt_output_name(output));
+ res = igt_debugfs_simple_read(dir, link_param ? "i915_dp_force_link_rate" :
+ "i915_dp_force_lane_count", buf, sizeof(buf));
+ close(dir);
+ igt_require(res >= 0);
+
+ /*
+ * Check we have a mode enabled for the output
+ * If so we will have current active link rate
+ * marked with a *
+ */
+ star_ptr = strstr(buf, "*");
+
+ if (star_ptr) {
+ param_ptr = star_ptr - 1;
+ while (param_ptr > buf && isdigit(*param_ptr))
+ param_ptr--;
+
+ param_ptr++;
+ igt_assert(sscanf(param_ptr, "%d", &ret) == 1);
+ }
+ return ret;
+}
+
+/**
+ * igt_get_dp_max_link_param:
+ * @drm_fd: A drm file descriptor
+ * @output: The output to query
+ * @link_param: 0 for lane count, 1 for link rate
+ *
+ * Get the max link_rate / lane_count supported by the sink.
+ *
+ * Returns: max link_rate / lane_count supported by the sink.
+ */
+int igt_get_dp_max_link_param(int drm_fd, igt_output_t *output, int link_param)
+{
+ char buf[512];
+ int dir, res;
+ int max_link_param;
+
+ dir = igt_debugfs_connector_dir(drm_fd, output->name, O_DIRECTORY);
+ igt_assert_f(dir >= 0, "Failed to open debugfs dir for connector %s\n",
+ igt_output_name(output));
+ res = igt_debugfs_simple_read(dir, link_param ? "i915_dp_max_link_rate" :
+ "i915_dp_max_lane_count", buf, sizeof(buf));
+ close(dir);
+ igt_require_f(res >= 0, "Couldn't read i915_dp_max_link_rate");
+
+ igt_assert(sscanf(buf, "%d", &max_link_param) == 1);
+
+ return max_link_param;
+}
+
+/**
+ * igt_force_link_retrain:
+ * @drm_fd: A drm file descriptor
+ * @output: Target output
+ * @retrain_count: number of retraining required
+ *
+ * Force link retrain on the output.
+ */
+void igt_force_link_retrain(int drm_fd, igt_output_t *output, int retrain_count)
+{
+ int dir;
+ char value[2];
+
+ snprintf(value, sizeof(value), "%d", retrain_count);
+ dir = igt_debugfs_connector_dir(drm_fd, output->name, O_RDONLY);
+ igt_assert_f(dir >= 0, "Failed to open debugfs dir for connector %s\n",
+ igt_output_name(output));
+ igt_sysfs_write(dir, "i915_dp_force_link_retrain", value, sizeof(value));
+ close(dir);
+}
+
+/**
+ * igt_force_lt_failure:
+ * @drm_fd: A drm file descriptor
+ * @output: Target output
+ * @failure_count: 1 for same link param and
+ * 2 for reduced link params
+ *
+ * Force link training failure on the output.
+ * @failure_count: 1 for retraining with same link params
+ * 2 for retraining with reduced link params
+ */
+void igt_force_lt_failure(int drm_fd, igt_output_t *output, int failure_count)
+{
+ int dir;
+ char value[2];
+
+ snprintf(value, sizeof(value), "%d", failure_count);
+ dir = igt_debugfs_connector_dir(drm_fd, output->name, O_RDONLY);
+ igt_assert_f(dir >= 0, "Failed to open debugfs dir for connector %s\n",
+ igt_output_name(output));
+ igt_sysfs_write(dir, "i915_dp_force_link_training_failure",
+ value, sizeof(value));
+ close(dir);
+}
+
+/**
+ * igt_get_dp_link_retrain_disabled:
+ * @drm_fd: A drm file descriptor
+ * @output: Target output
+ *
+ * Returns: True if link retrain disabled, false otherwise
+ */
+bool igt_get_dp_link_retrain_disabled(int drm_fd, igt_output_t *output)
+{
+ int dir, res;
+ char buf[512];
+
+ dir = igt_debugfs_connector_dir(drm_fd, output->name, O_RDONLY);
+ igt_assert_f(dir >= 0, "Failed to open debugfs dir for connector %s\n",
+ igt_output_name(output));
+ res = igt_debugfs_simple_read(dir,
+ "i915_dp_link_retrain_disabled",
+ buf, sizeof(buf));
+ close(dir);
+ igt_require(res >= 0);
+ return strstr(buf, "yes");
+}
+
+/**
+ * Checks if the force link training failure debugfs
+ * is available for a specific output.
+ *
+ * @drmfd: file descriptor of the DRM device.
+ * @output: output to check.
+ * Returns:
+ * true if the debugfs is available, false otherwise.
+ */
+bool igt_has_force_link_training_failure_debugfs(int drmfd, igt_output_t *output)
+{
+ int debugfs_fd, ret;
+ char buf[512];
+
+ igt_assert_f(output->name, "Invalid output\n");
+ debugfs_fd = igt_debugfs_connector_dir(drmfd, output->name, O_RDONLY);
+ if (debugfs_fd < 0)
+ return false;
+ ret = igt_debugfs_simple_read(debugfs_fd,
+ "i915_dp_force_link_training_failure",
+ buf, sizeof(buf));
+ close(debugfs_fd);
+ return ret >= 0;
+}
+
+/**
+ * igt_get_dp_pending_lt_failures:
+ * @drm_fd: A drm file descriptor
+ * @output: Target output
+ *
+ * Returns: Number of pending link training failures.
+ */
+int igt_get_dp_pending_lt_failures(int drm_fd, igt_output_t *output)
+{
+ int dir, res, ret;
+ char buf[512];
+
+ dir = igt_debugfs_connector_dir(drm_fd, output->name, O_RDONLY);
+ igt_assert_f(dir >= 0, "Failed to open debugfs dir for connector %s\n",
+ igt_output_name(output));
+ res = igt_debugfs_simple_read(dir, "i915_dp_force_link_training_failure", buf, sizeof(buf));
+ close(dir);
+ igt_require(res >= 0);
+ sscanf(buf, "%d", &ret);
+ return ret;
+}
+
+/**
+ * igt_dp_pending_retrain:
+ * @drm_fd: A drm file descriptor
+ * @output: Target output
+ *
+ * Returns: Number of pending link retrains.
+ */
+int igt_get_dp_pending_retrain(int drm_fd, igt_output_t *output)
+{
+ int dir, res, ret;
+ char buf[512];
+
+ dir = igt_debugfs_connector_dir(drm_fd, output->name, O_RDONLY);
+ igt_assert_f(dir >= 0, "Failed to open debugfs dir for connector %s\n",
+ igt_output_name(output));
+ res = igt_debugfs_simple_read(dir, "i915_dp_force_link_retrain", buf, sizeof(buf));
+ close(dir);
+ igt_require(res >= 0);
+ sscanf(buf, "%d", &ret);
+ return ret;
+}
diff --git a/lib/igt_kms.h b/lib/igt_kms.h
index 25ba50916..895bc9d04 100644
--- a/lib/igt_kms.h
+++ b/lib/igt_kms.h
@@ -1224,5 +1224,15 @@ bool intel_pipe_output_combo_valid(igt_display_t *display);
bool igt_check_output_is_dp_mst(igt_output_t *output);
int igt_get_dp_mst_connector_id(igt_output_t *output);
int get_num_scalers(igt_display_t *display, enum pipe pipe);
+int igt_get_dp_link_param_set_for_output(int drm_fd, igt_output_t *output,
+ int link_param);
+int igt_get_dp_max_link_param(int drm_fd, igt_output_t *output,
+ int link_param);
+void igt_force_link_retrain(int drm_fd, igt_output_t *output, int retrain_count);
+void igt_force_lt_failure(int drm_fd, igt_output_t *output, int failure_count);
+bool igt_get_dp_link_retrain_disabled(int drm_fd, igt_output_t *output);
+bool igt_has_force_link_training_failure_debugfs(int drmfd, igt_output_t *output);
+int igt_get_dp_pending_lt_failures(int drm_fd, igt_output_t *output);
+int igt_get_dp_pending_retrain(int drm_fd, igt_output_t *output);
#endif /* __IGT_KMS_H__ */
--
2.43.0
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