drm/nv50/kms: use dac loadval from vbios, where it's available

Regression from merging the old nv50/nvd9 code together, and may be
needed to fully fix fdo#64904.

The value is ignored completely by the hardware starting from nva3.

Reported-by: Emil Velikov <emil.l.velikov@gmail.com>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

1 files changed, 3 insertions, 1 deletions

diff --git a/drivers/gpu/drm/nouveau/nv50_display.c b/drivers/gpu/drm/nouveau/nv50_display.c
index 325887390677..e843cf86bcce 100644
--- a/drivers/gpu/drm/nouveau/nv50_display.c
+++ b/drivers/gpu/drm/nouveau/nv50_display.c
@@ -1554,7 +1554,9 @@ nv50_dac_detect(struct drm_encoder *encoder, struct drm_connector *connector)
 {
         struct nv50_disp *disp = nv50_disp(encoder->dev);
         int ret, or = nouveau_encoder(encoder)->or;
-        u32 load = 0;
+        u32 load = nouveau_drm(encoder->dev)->vbios.dactestval;
+        if (load == 0)
+                load = 340;
 
         ret = nv_exec(disp->core, NV50_DISP_DAC_LOAD + or, &load, sizeof(load));
         if (ret || load != 7)