intel: Add a vtbl hook for determining if a format is renderable.

By relying on just intel_span_supports_format, some formats that
aren't supported pre-gen4 were not reporting FBO incomplete.  And we
also complained in stderr when it happened on i915 because draw_region
gets called before framebuffer completeness validation.

src/mesa/drivers/dri/i915/i830_vtbl.c

@@ -585,6 +585,27 @@ i830_destroy_context(struct intel_context *intel)
    _tnl_free_vertices(&intel->ctx);
 }
 
+static uint32_t i830_render_target_format_for_mesa_format[MESA_FORMAT_COUNT] =
+{
+   [MESA_FORMAT_ARGB8888] = DV_PF_8888,
+   [MESA_FORMAT_XRGB8888] = DV_PF_8888,
+   [MESA_FORMAT_RGB565] = DV_PF_565,
+   [MESA_FORMAT_ARGB1555] = DV_PF_1555,
+   [MESA_FORMAT_ARGB4444] = DV_PF_4444,
+};
+
+static bool
+i830_render_target_supported(gl_format format)
+{
+   if (format == MESA_FORMAT_S8_Z24 ||
+       format == MESA_FORMAT_X8_Z24 ||
+       format == MESA_FORMAT_Z16) {
+      return true;
+   }
+
+   return i830_render_target_format_for_mesa_format[format] != 0;
+}
+
 static void
 i830_set_draw_region(struct intel_context *intel,
                      struct intel_region *color_regions[],
@@ -624,24 +645,7 @@ i830_set_draw_region(struct intel_context *intel,
             DSTORG_VERT_BIAS(0x8) | DEPTH_IS_Z);    /* .5 */
 
    if (irb != NULL) {
-      switch (irb->Base.Format) {
-      case MESA_FORMAT_ARGB8888:
-      case MESA_FORMAT_XRGB8888:
-	 value |= DV_PF_8888;
-	 break;
-      case MESA_FORMAT_RGB565:
-	 value |= DV_PF_565;
-	 break;
-      case MESA_FORMAT_ARGB1555:
-	 value |= DV_PF_1555;
-	 break;
-      case MESA_FORMAT_ARGB4444:
-	 value |= DV_PF_4444;
-	 break;
-      default:
-	 _mesa_problem(ctx, "Bad renderbuffer format: %d\n",
-		       irb->Base.Format);
-      }
+      value |= i830_render_target_format_for_mesa_format[irb->Base.Format];
    }
 
    if (depth_region && depth_region->cpp == 4) {
@@ -729,4 +733,5 @@ i830InitVtbl(struct i830_context *i830)
    i830->intel.vtbl.assert_not_dirty = i830_assert_not_dirty;
    i830->intel.vtbl.finish_batch = intel_finish_vb;
    i830->intel.vtbl.invalidate_state = i830_invalidate_state;
+   i830->intel.vtbl.render_target_supported = i830_render_target_supported;
 }

src/mesa/drivers/dri/i915/i915_vtbl.c

@@ -524,6 +524,27 @@ i915_set_buf_info_for_region(uint32_t *state, struct intel_region *region,
    }
 }
 
+static uint32_t i915_render_target_format_for_mesa_format[MESA_FORMAT_COUNT] =
+{
+   [MESA_FORMAT_ARGB8888] = DV_PF_8888,
+   [MESA_FORMAT_XRGB8888] = DV_PF_8888,
+   [MESA_FORMAT_RGB565] = DV_PF_565 | DITHER_FULL_ALWAYS,
+   [MESA_FORMAT_ARGB1555] = DV_PF_1555 | DITHER_FULL_ALWAYS,
+   [MESA_FORMAT_ARGB4444] = DV_PF_4444 | DITHER_FULL_ALWAYS,
+};
+
+static bool
+i915_render_target_supported(gl_format format)
+{
+   if (format == MESA_FORMAT_S8_Z24 ||
+       format == MESA_FORMAT_X8_Z24 ||
+       format == MESA_FORMAT_Z16) {
+      return true;
+   }
+
+   return i915_render_target_format_for_mesa_format[format] != 0;
+}
+
 static void
 i915_set_draw_region(struct intel_context *intel,
                      struct intel_region *color_regions[],
@@ -563,24 +584,7 @@ i915_set_draw_region(struct intel_context *intel,
             DSTORG_VERT_BIAS(0x8) |     /* .5 */
             LOD_PRECLAMP_OGL | TEX_DEFAULT_COLOR_OGL);
    if (irb != NULL) {
-      switch (irb->Base.Format) {
-      case MESA_FORMAT_ARGB8888:
-      case MESA_FORMAT_XRGB8888:
-	 value |= DV_PF_8888;
-	 break;
-      case MESA_FORMAT_RGB565:
-	 value |= DV_PF_565 | DITHER_FULL_ALWAYS;
-	 break;
-      case MESA_FORMAT_ARGB1555:
-	 value |= DV_PF_1555 | DITHER_FULL_ALWAYS;
-	 break;
-      case MESA_FORMAT_ARGB4444:
-	 value |= DV_PF_4444 | DITHER_FULL_ALWAYS;
-	 break;
-      default:
-	 _mesa_problem(ctx, "Bad renderbuffer format: %d\n",
-		       irb->Base.Format);
-      }
+      value |= i915_render_target_format_for_mesa_format[irb->Base.Format];
    }
 
    /* This isn't quite safe, thus being hidden behind an option.  When changing
@@ -687,4 +691,5 @@ i915InitVtbl(struct i915_context *i915)
    i915->intel.vtbl.update_texture_state = i915UpdateTextureState;
    i915->intel.vtbl.assert_not_dirty = i915_assert_not_dirty;
    i915->intel.vtbl.finish_batch = intel_finish_vb;
+   i915->intel.vtbl.render_target_supported = i915_render_target_supported;
 }

src/mesa/drivers/dri/i965/brw_vtbl.c

@@ -203,4 +203,5 @@ void brwInitVtbl( struct brw_context *brw )
    brw->intel.vtbl.destroy = brw_destroy_context;
    brw->intel.vtbl.set_draw_region = brw_set_draw_region;
    brw->intel.vtbl.debug_batch = brw_debug_batch;
+   brw->intel.vtbl.render_target_supported = brw_render_target_supported;
 }

src/mesa/drivers/dri/i965/brw_wm.h

@@ -474,5 +474,6 @@ struct gl_shader *brw_new_shader(struct gl_context *ctx, GLuint name, GLuint typ
 struct gl_shader_program *brw_new_shader_program(struct gl_context *ctx, GLuint name);
 
 bool brw_color_buffer_write_enabled(struct brw_context *brw);
+bool brw_render_target_supported(gl_format format);
 
 #endif

src/mesa/drivers/dri/i965/brw_wm_surface_state.c

@@ -42,7 +42,7 @@
 #include "brw_context.h"
 #include "brw_state.h"
 #include "brw_defines.h"
-
+#include "brw_wm.h"
 
 static GLuint translate_tex_target( GLenum target )
 {
@@ -103,6 +103,21 @@ static uint32_t brw_format_for_mesa_format[MESA_FORMAT_COUNT] =
    [MESA_FORMAT_SIGNED_RGBA8888_REV] = BRW_SURFACEFORMAT_R8G8B8A8_SNORM,
 };
 
+bool
+brw_render_target_supported(gl_format format)
+{
+   if (format == MESA_FORMAT_S8_Z24 ||
+       format == MESA_FORMAT_X8_Z24 ||
+       format == MESA_FORMAT_Z16) {
+      return true;
+   }
+
+   /* Not exactly true, as some of those formats are not renderable.
+    * But at least we know how to translate them.
+    */
+   return brw_format_for_mesa_format[format] != 0;
+}
+
 static GLuint translate_tex_format( gl_format mesa_format,
                                     GLenum internal_format,
 				    GLenum depth_mode )

src/mesa/drivers/dri/intel/intel_context.h

@@ -149,6 +149,7 @@ struct intel_context
       void (*assert_not_dirty) (struct intel_context *intel);
 
       void (*debug_batch)(struct intel_context *intel);
+      bool (*render_target_supported)(gl_format format);
    } vtbl;
 
    struct dri_metaops meta;

src/mesa/drivers/dri/intel/intel_fbo.c

@@ -564,6 +564,7 @@ intel_finish_render_texture(struct gl_context * ctx,
 static void
 intel_validate_framebuffer(struct gl_context *ctx, struct gl_framebuffer *fb)
 {
+   struct intel_context *intel = intel_context(ctx);
    const struct intel_renderbuffer *depthRb =
       intel_get_renderbuffer(fb, BUFFER_DEPTH);
    const struct intel_renderbuffer *stencilRb =
@@ -612,7 +613,8 @@ intel_validate_framebuffer(struct gl_context *ctx, struct gl_framebuffer *fb)
 	 continue;
       }
 
-      if (!intel_span_supports_format(irb->Base.Format)) {
+      if (!intel_span_supports_format(irb->Base.Format) ||
+	  !intel->vtbl.render_target_supported(irb->Base.Format)) {
 	 DBG("Unsupported texture/renderbuffer format attached: %s\n",
 	     _mesa_get_format_name(irb->Base.Format));
 	 fb->_Status = GL_FRAMEBUFFER_UNSUPPORTED_EXT;