drm/i915: Add display WA #1175 for planes ending close to right screen edge

As described in the WA on GLK and CNL planes on the right edge of the
screen that have less than 4 pixels visible from the beginning of the
plane to the edge of the screen can cause FIFO underflow and display
corruption.

On GLK/CNL I could trigger the problem only if the plane was at the same
time also aligned to the top edge of the screen (after clipping) and
there were exactly 2 pixels visible from the start of the plane to the
right edge of the screen (so couldn't trigger it with 1 or 3 pixels
visible). Nevertheless, to be sure, I also applied the WA for these cases.

I also couldn't see any problem with the cursor plane and later Art
confirmed that it's not affected, so the WA is applied only for the
other plane types.

v2:
- Use -ERANGE instead of -EINVAL. (Chris)

Signed-off-by: Imre Deak <imre.deak@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180116112415.22060-1-imre.deak@intel.com

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index f9372a21e32665c7e20a6b9d208ad043d0d8d495..eba716e6a7a7daf6872237ba817de04f22bd88e2 100644 (file)
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -2931,14 +2931,19 @@ static bool skl_check_main_ccs_coordinates(struct intel_plane_state *plane_state
        return true;
 }
 
-static int skl_check_main_surface(struct intel_plane_state *plane_state)
+static int skl_check_main_surface(const struct intel_crtc_state *crtc_state,
+                                 struct intel_plane_state *plane_state)
 {
+       struct drm_i915_private *dev_priv =
+               to_i915(plane_state->base.plane->dev);
        const struct drm_framebuffer *fb = plane_state->base.fb;
        unsigned int rotation = plane_state->base.rotation;
        int x = plane_state->base.src.x1 >> 16;
        int y = plane_state->base.src.y1 >> 16;
        int w = drm_rect_width(&plane_state->base.src) >> 16;
        int h = drm_rect_height(&plane_state->base.src) >> 16;
+       int dst_x = plane_state->base.dst.x1;
+       int pipe_src_w = crtc_state->pipe_src_w;
        int max_width = skl_max_plane_width(fb, 0, rotation);
        int max_height = 4096;
        u32 alignment, offset, aux_offset = plane_state->aux.offset;
@@ -2949,6 +2954,20 @@ static int skl_check_main_surface(struct intel_plane_state *plane_state)
                return -EINVAL;
        }
 
+       /*
+        * Display WA #1175: cnl,glk
+        * Planes other than the cursor may cause FIFO underflow and display
+        * corruption if starting less than 4 pixels from the right edge of
+        * the screen.
+        */
+       if ((IS_GEMINILAKE(dev_priv) || IS_CANNONLAKE(dev_priv)) &&
+           dst_x > pipe_src_w - 4) {
+               DRM_DEBUG_KMS("requested plane X start position %d invalid (valid range %d-%d)\n",
+                             dst_x,
+                             0, pipe_src_w - 4);
+               return -ERANGE;
+       }
+
        intel_add_fb_offsets(&x, &y, plane_state, 0);
        offset = intel_compute_tile_offset(&x, &y, plane_state, 0);
        alignment = intel_surf_alignment(fb, 0);
@@ -3073,7 +3092,8 @@ static int skl_check_ccs_aux_surface(struct intel_plane_state *plane_state)
        return 0;
 }
 
-int skl_check_plane_surface(struct intel_plane_state *plane_state)
+int skl_check_plane_surface(const struct intel_crtc_state *crtc_state,
+                           struct intel_plane_state *plane_state)
 {
        const struct drm_framebuffer *fb = plane_state->base.fb;
        unsigned int rotation = plane_state->base.rotation;
@@ -3113,7 +3133,7 @@ int skl_check_plane_surface(struct intel_plane_state *plane_state)
                plane_state->aux.y = 0;
        }
 
-       ret = skl_check_main_surface(plane_state);
+       ret = skl_check_main_surface(crtc_state, plane_state);
        if (ret)
                return ret;
 
@@ -12778,7 +12798,7 @@ intel_check_primary_plane(struct intel_plane *plane,
                return 0;
 
        if (INTEL_GEN(dev_priv) >= 9) {
-               ret = skl_check_plane_surface(state);
+               ret = skl_check_plane_surface(crtc_state, state);
                if (ret)
                        return ret;
 

diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index bb849b55548c60230486bcbb416a560f8aacb3a8..1695b2a76c139f5fc4ea03475fd5567fd1867ca9 100644 (file)
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1507,7 +1507,8 @@ u32 skl_plane_ctl(const struct intel_crtc_state *crtc_state,
                  const struct intel_plane_state *plane_state);
 u32 skl_plane_stride(const struct drm_framebuffer *fb, int plane,
                     unsigned int rotation);
-int skl_check_plane_surface(struct intel_plane_state *plane_state);
+int skl_check_plane_surface(const struct intel_crtc_state *crtc_state,
+                           struct intel_plane_state *plane_state);
 int i9xx_check_plane_surface(struct intel_plane_state *plane_state);
 
 /* intel_csr.c */

diff --git a/drivers/gpu/drm/i915/intel_sprite.c b/drivers/gpu/drm/i915/intel_sprite.c
index e4e4a1cbdd47d92b4acceab7d7337efdd9907b50..630d20eecf3c52ba94d057b33cbfed265fad519e 100644 (file)
--- a/drivers/gpu/drm/i915/intel_sprite.c
+++ b/drivers/gpu/drm/i915/intel_sprite.c
@@ -1028,7 +1028,7 @@ intel_check_sprite_plane(struct intel_plane *plane,
        dst->y2 = crtc_y + crtc_h;
 
        if (INTEL_GEN(dev_priv) >= 9) {
-               ret = skl_check_plane_surface(state);
+               ret = skl_check_plane_surface(crtc_state, state);
                if (ret)
                        return ret;