[PATCH 8/9] drm/i915/wm: Include ddb_y in skl_print_wm_changes() on pre-icl

Ville Syrjala
2026-03-19T11:41:20Z

From: Ville Syrjälä <ville.syrjala@linux.intel.com>

Pre-icl doesn't use a separate hardware plane for Y scanout,
and instead it's all handled magially by the hardware. We
do still need to allocate DDB space for the Y color plane
though (PLANE_NV12_BUF_CFG). Include that information in the
debugs so that we know where it ended up.

On icl+ the equivalent information is dumped as the hardware
Y plane's normal ddb allocation.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
---
drivers/gpu/drm/i915/display/skl_watermark.c | 11 +++++++++--
1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/skl_watermark.c b/drivers/gpu/drm/i915/display/skl_watermark.c
index 8687026935e9..345767349988 100644
--- a/drivers/gpu/drm/i915/display/skl_watermark.c
+++ b/drivers/gpu/drm/i915/display/skl_watermark.c
@@ -2735,10 +2735,17 @@ skl_print_wm_changes(struct intel_atomic_state *state)
old = &old_crtc_state->wm.skl.plane_ddb[plane_id];
new = &new_crtc_state->wm.skl.plane_ddb[plane_id];

- if (skl_ddb_entry_equal(old, new))
+ if (!skl_ddb_entry_equal(old, new))
+ skl_print_plane_ddb_changes(plane, old, new, " ddb");
+
+ if (DISPLAY_VER(display) >= 11)
continue;

- skl_print_plane_ddb_changes(plane, old, new, "ddb");
+ old = &old_crtc_state->wm.skl.plane_ddb_y[plane_id];
+ new = &new_crtc_state->wm.skl.plane_ddb_y[plane_id];
+
+ if (!skl_ddb_entry_equal(old, new))
+ skl_print_plane_ddb_changes(plane, old, new, "ddb_y");
}

for_each_intel_plane_on_crtc(display->drm, crtc, plane) {
--
2.52.0