drm/i915/gen9+: Fix initial readout for Y tiled framebuffers

If BIOS configured a Y tiled FB we failed to set up the backing object
tiling accordingly, leading to a lack of GT fence installed and a
garbled console.

The problem was bisected to
commit 011f22eb545a ("drm/i915: Do NOT skip the first 4k of stolen memory for pre-allocated buffers v2")
but it just revealed a pre-existing issue.

Kudos to Ville who suspected a missing fence looking at the corruption
on the screen.

Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
Cc: Hans de Goede <hdegoede@redhat.com>
Cc: <ronald@innovation.ch>
Cc: <stable@vger.kernel.org>
Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reported-by: <ronald@innovation.ch>
Tested-by: <ronald@innovation.ch>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=108264
Fixes: bc8d7dffacb1 ("drm/i915/skl: Provide a Skylake version of get_plane_config()")
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/20181016160011.28347-1-imre.deak@intel.com

diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 3999d02cd18ce0f4420b2ea99c26c068a7a442bf..cfed45b9957a5e594b3943b515997ee687829303 100644 (file)
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -2673,6 +2673,17 @@ intel_alloc_initial_plane_obj(struct intel_crtc *crtc,
        if (size_aligned * 2 > dev_priv->stolen_usable_size)
                return false;
 
+       switch (fb->modifier) {
+       case DRM_FORMAT_MOD_LINEAR:
+       case I915_FORMAT_MOD_X_TILED:
+       case I915_FORMAT_MOD_Y_TILED:
+               break;
+       default:
+               DRM_DEBUG_DRIVER("Unsupported modifier for initial FB: 0x%llx\n",
+                                fb->modifier);
+               return false;
+       }
+
        mutex_lock(&dev->struct_mutex);
        obj = i915_gem_object_create_stolen_for_preallocated(dev_priv,
                                                             base_aligned,
@@ -2682,8 +2693,17 @@ intel_alloc_initial_plane_obj(struct intel_crtc *crtc,
        if (!obj)
                return false;
 
-       if (plane_config->tiling == I915_TILING_X)
-               obj->tiling_and_stride = fb->pitches[0] | I915_TILING_X;
+       switch (plane_config->tiling) {
+       case I915_TILING_NONE:
+               break;
+       case I915_TILING_X:
+       case I915_TILING_Y:
+               obj->tiling_and_stride = fb->pitches[0] | plane_config->tiling;
+               break;
+       default:
+               MISSING_CASE(plane_config->tiling);
+               return false;
+       }
 
        mode_cmd.pixel_format = fb->format->format;
        mode_cmd.width = fb->width;
@@ -8837,6 +8857,7 @@ skylake_get_initial_plane_config(struct intel_crtc *crtc,
                fb->modifier = I915_FORMAT_MOD_X_TILED;
                break;
        case PLANE_CTL_TILED_Y:
+               plane_config->tiling = I915_TILING_Y;
                if (val & PLANE_CTL_RENDER_DECOMPRESSION_ENABLE)
                        fb->modifier = I915_FORMAT_MOD_Y_TILED_CCS;
                else