[igt-dev] [PATCH i-g-t 3/3] tests/kms_plane: Throw away yet another bi

Ville Syrjala
2019-06-28T19:44:51Z

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

CHV pipe A/C sprites are causing a crc mismatch with BT.601
when we keep the six msbs. If we throw away one more bit we get
matches for BT.601. BT.709 matches even with 6 bits, as do the
pipe B planes with their programmable CSC. Also IVB and KBL
were both happy with 6 bits, so doesn't seem that that these
CHV mismatches are due to bugs in our code, just the hw is
a bit imprecise.

Cc: Uma Shankar <uma.shankar@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
---
tests/kms_plane.c | 13 ++++++++++---
1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/tests/kms_plane.c b/tests/kms_plane.c
index 13d36254dfe3..e4f3b8d68748 100644
--- a/tests/kms_plane.c
+++ b/tests/kms_plane.c
@@ -30,6 +30,13 @@
#include <stdio.h>
#include <string.h>

+/*
+ * Throw away enough lsbs in pixel formats tests
+ * to get a match despite some differences between
+ * the software and hardware YCbCr<->RGB conversion
+ * routines.
+ */
+#define LUT_MASK 0xf800

typedef struct {
float red;
@@ -690,7 +697,7 @@ static bool test_format_plane(data_t *data, enum pipe pipe,
continue;

if (format == DRM_FORMAT_C8) {
- if (!set_c8_legacy_lut(data, pipe, 0xfc00))
+ if (!set_c8_legacy_lut(data, pipe, LUT_MASK))
continue;
} else {
if (!igt_fb_supported_format(format))
@@ -709,7 +716,7 @@ static bool test_format_plane(data_t *data, enum pipe pipe,
ref_crc, &fb);

if (format == DRM_FORMAT_C8)
- set_legacy_lut(data, pipe, 0xfc00);
+ set_legacy_lut(data, pipe, LUT_MASK);
}

igt_pipe_crc_stop(data->pipe_crc);
@@ -744,7 +751,7 @@ test_pixel_formats(data_t *data, enum pipe pipe)

igt_display_commit2(&data->display, data->display.is_atomic ? COMMIT_ATOMIC : COMMIT_LEGACY);

- set_legacy_lut(data, pipe, 0xfc00);
+ set_legacy_lut(data, pipe, LUT_MASK);

test_init(data, pipe);

--
2.21.0