diff options
| author | Ville Syrjälä <ville.syrjala@linux.intel.com> | 2023-04-13 19:49:12 +0300 |
|---|---|---|
| committer | Ville Syrjälä <ville.syrjala@linux.intel.com> | 2023-05-26 18:02:09 +0300 |
| commit | 2587c63aaaf47f6f4ea9d90047910534a3ecf432 (patch) | |
| tree | a9f2cdcb4dfe3dc452c286b3a4bc747b95a4a7f4 | |
| parent | d9ce4e430790ba4f45e5febd7b4bd87b0f23563e (diff) | |
drm/i915: Fix CHV CGM CSC coefficient sign handling
The CHV CGM CSC coefficients are in s4.12 two's complement
format. Fix the CTM->CGM conversion to handle that correctly
instead of pretending that the hw coefficients are also
in some sign-magnitude format.
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230413164916.4221-4-ville.syrjala@linux.intel.com
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
| -rw-r--r-- | drivers/gpu/drm/i915/display/intel_color.c | 46 |
1 files changed, 29 insertions, 17 deletions
diff --git a/drivers/gpu/drm/i915/display/intel_color.c b/drivers/gpu/drm/i915/display/intel_color.c index 0f2c3c22cf59..7c14b2aba9e5 100644 --- a/drivers/gpu/drm/i915/display/intel_color.c +++ b/drivers/gpu/drm/i915/display/intel_color.c @@ -568,29 +568,41 @@ static void icl_load_csc_matrix(const struct intel_crtc_state *crtc_state) icl_update_output_csc(crtc, &crtc_state->output_csc); } -static void chv_cgm_csc_convert_ctm(const struct intel_crtc_state *crtc_state, - struct intel_csc_matrix *csc) +static u16 ctm_to_twos_complement(u64 coeff, int int_bits, int frac_bits) { - const struct drm_color_ctm *ctm = crtc_state->hw.ctm->data; - int i; + s64 c = CTM_COEFF_ABS(coeff); - for (i = 0; i < 9; i++) { - u64 abs_coeff = ((1ULL << 63) - 1) & ctm->matrix[i]; + /* leave an extra bit for rounding */ + c >>= 32 - frac_bits - 1; - /* Round coefficient. */ - abs_coeff += 1 << (32 - 13); - /* Clamp to hardware limits. */ - abs_coeff = clamp_val(abs_coeff, 0, CTM_COEFF_8_0 - 1); + /* round and drop the extra bit */ + c = (c + 1) >> 1; - csc->coeff[i] = 0; + if (CTM_COEFF_NEGATIVE(coeff)) + c = -c; - /* Write coefficients in S3.12 format. */ - if (ctm->matrix[i] & (1ULL << 63)) - csc->coeff[i] |= 1 << 15; + c = clamp(c, -(s64)BIT(int_bits + frac_bits - 1), + (s64)(BIT(int_bits + frac_bits - 1) - 1)); - csc->coeff[i] |= ((abs_coeff >> 32) & 7) << 12; - csc->coeff[i] |= (abs_coeff >> 20) & 0xfff; - } + return c & (BIT(int_bits + frac_bits) - 1); +} + +/* + * CHV Color Gamut Mapping (CGM) CSC + * |r| | c0 c1 c2 | |r| + * |g| = | c3 c4 c5 | x |g| + * |b| | c6 c7 c8 | |b| + * + * Coefficients are two's complement s4.12. + */ +static void chv_cgm_csc_convert_ctm(const struct intel_crtc_state *crtc_state, + struct intel_csc_matrix *csc) +{ + const struct drm_color_ctm *ctm = crtc_state->hw.ctm->data; + int i; + + for (i = 0; i < 9; i++) + csc->coeff[i] = ctm_to_twos_complement(ctm->matrix[i], 4, 12); } static void chv_load_cgm_csc(struct intel_crtc *crtc, |