[PATCH 2/2] drm/i915: add more debug info for when atomic updates fail

Jesse Barnes
2015-09-10T15:34:36Z

I used these additional fields to track down the issue I saw on HSW.

References: https://bugs.freedesktop.org/show_bug.cgi?id=91579
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
---
drivers/gpu/drm/i915/intel_drv.h | 2 ++
drivers/gpu/drm/i915/intel_sprite.c | 16 ++++++++++++----
2 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 46484e4..90cad50 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -565,6 +565,8 @@ struct intel_crtc {

unsigned start_vbl_count;
ktime_t start_vbl_time;
+ int min_vbl, max_vbl;
+ int scanline_start;

struct intel_crtc_atomic_commit atomic;

diff --git a/drivers/gpu/drm/i915/intel_sprite.c b/drivers/gpu/drm/i915/intel_sprite.c
index 0c2c62f..ff8c9d5 100644
--- a/drivers/gpu/drm/i915/intel_sprite.c
+++ b/drivers/gpu/drm/i915/intel_sprite.c
@@ -94,6 +94,9 @@ void intel_pipe_update_start(struct intel_crtc *crtc)
min = vblank_start - usecs_to_scanlines(mode, 100);
max = vblank_start - 1;

+ crtc->min_vbl = min;
+ crtc->max_vbl = max;
+
local_irq_disable();
crtc->start_vbl_count = 0;

@@ -122,8 +125,10 @@ void intel_pipe_update_start(struct intel_crtc *crtc)
* scanline_offset used to correct the DSL readout.)
*/
scanline = intel_get_crtc_scanline(crtc);
- if (scanline > 2 && (scanline < min || scanline > max))
+ if (scanline > 2 && (scanline < min || scanline > max)) {
+ crtc->scanline_start = scanline;
break;
+ }

if (timeout <= 0) {
DRM_ERROR("Potential atomic update failure on pipe %c\n",
@@ -169,10 +174,13 @@ void intel_pipe_update_end(struct intel_crtc *crtc)

local_irq_enable();

- if (crtc->start_vbl_count && crtc->start_vbl_count != end_vbl_count)
- DRM_ERROR("Atomic update failure on pipe %c (start=%u end=%u) time %lld us\n",
+ if (crtc->start_vbl_count && crtc->start_vbl_count != end_vbl_count) {
+ DRM_ERROR("Atomic update failure on pipe %c (start=%u end=%u) time %lld us, min %d, max %d, scanline start %d, end %d\n",
pipe_name(pipe), crtc->start_vbl_count, end_vbl_count,
- ktime_us_delta(end_vbl_time, crtc->start_vbl_time));
+ ktime_us_delta(end_vbl_time, crtc->start_vbl_time),
+ crtc->min_vbl, crtc->max_vbl, crtc->scanline_start,
+ intel_get_crtc_scanline(crtc));
+ }
}

static void
--
1.9.1