drm/xe/debugfs: Add dump of default LRCs' MI instructions

For non-RCS engines, nearly all of the LRC state is composed of MI
instructions (specifically MI_LOAD_REGISTER_IMM).  Providing a dump
interface allows us to verify that the context image layout matches
what's documented in the bspec, and also allows us to check whether LRC
workarounds are being properly captured by the default state we record
at startup.

For now, the non-MI instructions found in the RCS and CCS engines will
dump as "unknown;" parsing of those will be added in a follow-up patch.

v2:
 - Add raw instruction header as well as decoded meaning.  (Lucas)
 - Check that num_dw isn't greater than remaining_dw for instructions
   that have a "# dwords" field.  (Lucas)
 - Clarify comment about skipping over ppHWSP.  (Lucas)

Bspec: 64993
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://lore.kernel.org/r/20231016163449.1300701-13-matthew.d.roper@intel.com
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>

1 files changed, 46 insertions, 0 deletions

diff --git a/drivers/gpu/drm/xe/xe_gt_debugfs.c b/drivers/gpu/drm/xe/xe_gt_debugfs.c
index cd6d28c7b923..c4b67cf09f8f 100644
--- a/drivers/gpu/drm/xe/xe_gt_debugfs.c
+++ b/drivers/gpu/drm/xe/xe_gt_debugfs.c
@@ -15,6 +15,7 @@
 #include "xe_gt_mcr.h"
 #include "xe_gt_topology.h"
 #include "xe_hw_engine.h"
+#include "xe_lrc.h"
 #include "xe_macros.h"
 #include "xe_pat.h"
 #include "xe_reg_sr.h"
@@ -149,6 +150,46 @@ static int pat(struct seq_file *m, void *data)
 	return 0;
 }
 
+static int rcs_default_lrc(struct seq_file *m, void *data)
+{
+	struct drm_printer p = drm_seq_file_printer(m);
+
+	xe_lrc_dump_default(&p, node_to_gt(m->private), XE_ENGINE_CLASS_RENDER);
+	return 0;
+}
+
+static int ccs_default_lrc(struct seq_file *m, void *data)
+{
+	struct drm_printer p = drm_seq_file_printer(m);
+
+	xe_lrc_dump_default(&p, node_to_gt(m->private), XE_ENGINE_CLASS_COMPUTE);
+	return 0;
+}
+
+static int bcs_default_lrc(struct seq_file *m, void *data)
+{
+	struct drm_printer p = drm_seq_file_printer(m);
+
+	xe_lrc_dump_default(&p, node_to_gt(m->private), XE_ENGINE_CLASS_COPY);
+	return 0;
+}
+
+static int vcs_default_lrc(struct seq_file *m, void *data)
+{
+	struct drm_printer p = drm_seq_file_printer(m);
+
+	xe_lrc_dump_default(&p, node_to_gt(m->private), XE_ENGINE_CLASS_VIDEO_DECODE);
+	return 0;
+}
+
+static int vecs_default_lrc(struct seq_file *m, void *data)
+{
+	struct drm_printer p = drm_seq_file_printer(m);
+
+	xe_lrc_dump_default(&p, node_to_gt(m->private), XE_ENGINE_CLASS_VIDEO_ENHANCE);
+	return 0;
+}
+
 static const struct drm_info_list debugfs_list[] = {
 	{"hw_engines", hw_engines, 0},
 	{"force_reset", force_reset, 0},
@@ -159,6 +200,11 @@ static const struct drm_info_list debugfs_list[] = {
 	{"register-save-restore", register_save_restore, 0},
 	{"workarounds", workarounds, 0},
 	{"pat", pat, 0},
+	{"default_lrc_rcs", rcs_default_lrc},
+	{"default_lrc_ccs", ccs_default_lrc},
+	{"default_lrc_bcs", bcs_default_lrc},
+	{"default_lrc_vcs", vcs_default_lrc},
+	{"default_lrc_vecs", vecs_default_lrc},
 };
 
 void xe_gt_debugfs_register(struct xe_gt *gt)