From: "Leo (Sunpeng) Li" <sunpeng.li@xxxxxxx>
We compose the two LUTs when pushing non-legacy gamma changes, and the
same needs to be done when setting legacy gamma.
If a non-legacy LUT has not been set (i.e. using the default value),
the legacy LUT will act independantly. However, instead of using DRM's
legacy gamma code-path, we adapt to the non-legacy path by upscaling the
LUT to non-legacy size.
It's also possible that the kernel driver doesn't support non-legacy
color management. In which case, we fall back to legacy gamma.
Signed-off-by: Leo (Sunpeng) Li <sunpeng.li at amd.com>
---
src/drmmode_display.c | 111 +++++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 109 insertions(+), 2 deletions(-)
diff --git a/src/drmmode_display.c b/src/drmmode_display.c
index 9c8c344..2b38a71 100644
--- a/src/drmmode_display.c
+++ b/src/drmmode_display.c
@@ -958,6 +958,63 @@ static void drmmode_lut_compose(uint16_t *a_red,
}
/**
+ * Resize a LUT, using linear interpolation.
+ *
+ * @in_(red|green|blue): Legacy LUT components
+ * @out_lut: The resized LUT is returned here, in DRM color LUT format.
+ * @len_in: Length of legacy LUT.
+ * @len_out: Length of out_lut, i.e. the target size.
+ */
+static void drmmode_lut_interpolate(uint16_t *in_red,
+ uint16_t *in_green,
+ uint16_t *in_blue,
+ struct drm_color_lut *out_lut,
+ uint32_t len_in, uint32_t len_out)
+{
+ uint32_t i_l, i_r, i;
+ uint32_t i_amax, i_bmax;
+ uint32_t coeff_ibmax;
+ uint64_t out_ibmax;
+ int color;
+ size_t struct_size = sizeof(struct drm_color_lut);
+
+ i_amax = len_in - 1;
+ i_bmax = len_out - 1;
+
+ /* See @drmmode_lut_compose for details */
+ for (color = 0; color < 3; color++) {
+ uint16_t *in, *out;
+
+ if (color == 0) {
+ in = in_red;
+ out = &out_lut[0].red;
+ } else if (color == 1) {
+ in = in_green;
+ out = &out_lut[0].green;
+ } else {
+ in = in_blue;
+ out = &out_lut[0].blue;
+ }
+
+ for (i = 0; i < len_out; i++) {
+
+ i_l = i * i_amax / i_bmax;
+ i_r = i_l + !!(i_amax - i_l);
+
+ coeff_ibmax = (i * i_amax) - (i_l * i_bmax);
+ out_ibmax = i_bmax * in[i_l] +
+ coeff_ibmax * (in[i_r] - in[i_l]);
+
+ *(uint16_t*)((void*)out + (i*struct_size)) =
+ out_ibmax / i_bmax;
+ }
+ }
+
+ for (i = 0; i < len_out; i++)
+ out_lut[i].reserved = 0;
+}
+
+/**
* Configure and change a color property on a CRTC, through RandR. Only the
* specified output will be affected, even if the CRTC is attached to multiple
* outputs. If the request is pending, then the change will make it's way into
@@ -1293,9 +1350,59 @@ drmmode_crtc_gamma_do_set(xf86CrtcPtr crtc, uint16_t *red, uint16_t *green,
{
drmmode_crtc_private_ptr drmmode_crtc = crtc->driver_private;
AMDGPUEntPtr pAMDGPUEnt = AMDGPUEntPriv(crtc->scrn);
+ struct drm_color_lut *composed;
+ uint32_t drm_prop_id, created_blob_id;
+ size_t bytes;
+ int ret;
+
+ drm_prop_id = get_drm_cm_prop_id(crtc, CM_GAMMA_LUT);
+ /* Use legacy if kernel does not support non-legacy gamma */
+ if (!drm_prop_id) {
+ drmModeCrtcSetGamma(pAMDGPUEnt->fd,
+ drmmode_crtc->mode_crtc->crtc_id,
+ size, red, green, blue);
+ return;
+ }
+
+ bytes = sizeof(*composed) * drmmode_crtc->gamma_lut_size;
+
+ composed = malloc(bytes);
+ if (!composed) {
+ xf86DrvMsg(crtc->scrn->scrnIndex, X_ERROR,
+ "Memory error allocating legacy LUT.");
+ return;
+ }
+
+ if (drmmode_crtc->gamma_lut)
+ drmmode_lut_compose(red, green, blue, drmmode_crtc->gamma_lut,
+ composed, size,
+ drmmode_crtc->gamma_lut_size);
+ else
+ drmmode_lut_interpolate(red, green, blue, composed,
+ size, drmmode_crtc->gamma_lut_size);
+
+ ret = drmModeCreatePropertyBlob(pAMDGPUEnt->fd, composed, bytes,
+ &created_blob_id);
+ if (ret) {
+ xf86DrvMsg(crtc->scrn->scrnIndex, X_ERROR,
+ "Creating Gamma LUT failed with errno %d\n",
+ ret);
+ free(composed);
+ return;
+ }
+
+ ret = drmModeObjectSetProperty(pAMDGPUEnt->fd,
+ drmmode_crtc->mode_crtc->crtc_id,
+ DRM_MODE_OBJECT_CRTC,
+ drm_prop_id,
+ (uint64_t)created_blob_id);
+
+ if (ret)
+ xf86DrvMsg(crtc->scrn->scrnIndex, X_ERROR,
+ "Setting Gamma LUT failed with errno %d\n",
+ ret);
- drmModeCrtcSetGamma(pAMDGPUEnt->fd, drmmode_crtc->mode_crtc->crtc_id,
- size, red, green, blue);
+ free(composed);
}
Bool
--
2.7.4
