drm/i915: clean up plane bpp confusion

- There is no 16bpc linear color format in our hw. gen4+ has a 16 bpc
  float layout, but we don't really support it.
- 10bpc is a gen4+ feature, fix up the support for it.
- Update_plane should never see a wrong fb bpp value, BUG in the
  corresponding cases.

v2: Rebase on top of Ville's plane pixel layout changes.

v3: Actually drop the old gen4 check for 10bpc planes, spotted
by Ville Syrjälä.

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 8 insertions, 12 deletions

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index e95c469afa6d..70c22b12b7c9 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -2113,8 +2113,7 @@ static int i9xx_update_plane(struct drm_crtc *crtc, struct drm_framebuffer *fb,
                 dspcntr |= DISPPLANE_RGBX101010;
                 break;
         default:
-                DRM_ERROR("Unknown pixel format 0x%08x\n", fb->pixel_format);
-                return -EINVAL;
+                BUG();
         }
 
         if (INTEL_INFO(dev)->gen >= 4) {
@@ -2207,8 +2206,7 @@ static int ironlake_update_plane(struct drm_crtc *crtc,
                 dspcntr |= DISPPLANE_RGBX101010;
                 break;
         default:
-                DRM_ERROR("Unknown pixel format 0x%08x\n", fb->pixel_format);
-                return -EINVAL;
+                BUG();
         }
 
         if (obj->tiling_mode != I915_TILING_NONE)
@@ -7400,21 +7398,19 @@ pipe_config_set_bpp(struct drm_crtc *crtc,
                 bpp = 8*3;
                 break;
         case 30:
+                if (INTEL_INFO(dev)->gen < 4) {
+                        DRM_DEBUG_KMS("10 bpc not supported on gen2/3\n");
+                        return -EINVAL;
+                }
+
                 bpp = 10*3;
                 break;
-        case 48:
-                bpp = 12*3;
-                break;
+        /* TODO: gen4+ supports 16 bpc floating point, too. */
         default:
                 DRM_DEBUG_KMS("unsupported depth\n");
                 return -EINVAL;
         }
 
-        if (fb->depth > 24 && !HAS_PCH_SPLIT(dev)) {
-                DRM_DEBUG_KMS("high depth not supported on gmch platforms\n");
-                return -EINVAL;
-        }
-
         pipe_config->pipe_bpp = bpp;
 
         /* Clamp display bpp to EDID value */