drm/nv50/disp: fix scaling of doublescan modes

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>

1 files changed, 18 insertions, 15 deletions

diff --git a/drivers/gpu/drm/nouveau/nv50_crtc.c b/drivers/gpu/drm/nouveau/nv50_crtc.c
index 998ac7195419..8f6c2ace3adf 100644
--- a/drivers/gpu/drm/nouveau/nv50_crtc.c
+++ b/drivers/gpu/drm/nouveau/nv50_crtc.c
@@ -195,7 +195,8 @@ nv50_crtc_set_scale(struct nouveau_crtc *nv_crtc, bool update)
         struct drm_crtc *crtc = &nv_crtc->base;
         struct drm_device *dev = crtc->dev;
         struct nouveau_channel *evo = nv50_display(dev)->master;
-        struct drm_display_mode *mode = &crtc->mode;
+        struct drm_display_mode *umode = &crtc->mode;
+        struct drm_display_mode *omode;
         int scaling_mode, ret;
         u32 ctrl = 0, oX, oY;
 
@@ -212,13 +213,15 @@ nv50_crtc_set_scale(struct nouveau_crtc *nv_crtc, bool update)
         /* start off at the resolution we programmed the crtc for, this
          * effectively handles NONE/FULL scaling
          */
-        if (scaling_mode != DRM_MODE_SCALE_NONE) {
-                oX = nv_connector->native_mode->hdisplay;
-                oY = nv_connector->native_mode->vdisplay;
-        } else {
-                oX = mode->hdisplay;
-                oY = mode->vdisplay;
-        }
+        if (scaling_mode != DRM_MODE_SCALE_NONE)
+                omode = nv_connector->native_mode;
+        else
+                omode = umode;
+
+        oX = omode->hdisplay;
+        oY = omode->vdisplay;
+        if (omode->flags & DRM_MODE_FLAG_DBLSCAN)
+                oY *= 2;
 
         /* add overscan compensation if necessary, will keep the aspect
          * ratio the same as the backend mode unless overridden by the
@@ -248,15 +251,15 @@ nv50_crtc_set_scale(struct nouveau_crtc *nv_crtc, bool update)
          */
         switch (scaling_mode) {
         case DRM_MODE_SCALE_CENTER:
-                oX = min((u32)mode->hdisplay, oX);
-                oY = min((u32)mode->vdisplay, oY);
+                oX = min((u32)umode->hdisplay, oX);
+                oY = min((u32)umode->vdisplay, oY);
                 /* fall-through */
         case DRM_MODE_SCALE_ASPECT:
                 if (oY < oX) {
-                        u32 aspect = (mode->hdisplay << 19) / mode->vdisplay;
+                        u32 aspect = (umode->hdisplay << 19) / umode->vdisplay;
                         oX = ((oY * aspect) + (aspect / 2)) >> 19;
                 } else {
-                        u32 aspect = (mode->vdisplay << 19) / mode->hdisplay;
+                        u32 aspect = (umode->vdisplay << 19) / umode->hdisplay;
                         oY = ((oX * aspect) + (aspect / 2)) >> 19;
                 }
                 break;
@@ -264,9 +267,9 @@ nv50_crtc_set_scale(struct nouveau_crtc *nv_crtc, bool update)
                 break;
         }
 
-        if (mode->hdisplay != oX || mode->vdisplay != oY ||
-            mode->flags & DRM_MODE_FLAG_INTERLACE ||
-            mode->flags & DRM_MODE_FLAG_DBLSCAN)
+        if (umode->hdisplay != oX || umode->vdisplay != oY ||
+            umode->flags & DRM_MODE_FLAG_INTERLACE ||
+            umode->flags & DRM_MODE_FLAG_DBLSCAN)
                 ctrl |= NV50_EVO_CRTC_SCALE_CTRL_ACTIVE;
 
         ret = RING_SPACE(evo, 5);