i965: Use MESA_FORMAT_AL1616 when appropriate

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

@@ -86,6 +86,9 @@ static GLuint translate_tex_format( gl_format mesa_format,
    case MESA_FORMAT_AL88:
       return BRW_SURFACEFORMAT_L8A8_UNORM;
 
+   case MESA_FORMAT_AL1616:
+      return BRW_SURFACEFORMAT_L16A16_UNORM;
+
    case MESA_FORMAT_RGB888:
       assert(0);		/* not supported for sampling */
       return BRW_SURFACEFORMAT_R8G8B8_UNORM;      

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

@@ -95,14 +95,20 @@ intelChooseTextureFormat(GLcontext * ctx, GLint internalFormat,
    case GL_COMPRESSED_LUMINANCE:
       return MESA_FORMAT_L8;
 
+   case GL_LUMINANCE12_ALPHA4:
+   case GL_LUMINANCE12_ALPHA12:
+   case GL_LUMINANCE16_ALPHA16:
+#ifndef I915
+      return MESA_FORMAT_AL1616;
+#else
+      /* FALLTHROUGH */
+#endif
+
    case 2:
    case GL_LUMINANCE_ALPHA:
    case GL_LUMINANCE4_ALPHA4:
    case GL_LUMINANCE6_ALPHA2:
    case GL_LUMINANCE8_ALPHA8:
-   case GL_LUMINANCE12_ALPHA4:
-   case GL_LUMINANCE12_ALPHA12:
-   case GL_LUMINANCE16_ALPHA16:
    case GL_COMPRESSED_LUMINANCE_ALPHA:
       return MESA_FORMAT_AL88;