glamor: Fall back to software for CopyPlane if we need to

glUniform4ui is available starting in GL{,ES} 3.0. Technically it's
also in EXT_gpu_shader4, but that's not worth supporting. There was also
a MESA_shading_language_130 spec proposed at one point; if that ever
gets finished, we can update epoxy to know about it and fix up the
feature check.

Signed-off-by: Adam Jackson <ajax@redhat.com>
Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>

glamor/glamor.c

@@ -616,6 +616,8 @@ glamor_init(ScreenPtr screen, unsigned int flags)
     glamor_priv->is_core_profile =
         gl_version >= 31 && !epoxy_has_gl_extension("GL_ARB_compatibility");
 
+    glamor_priv->can_copyplane = (gl_version >= 30);
+
     glamor_setup_debug_output(screen);
 
     glamor_priv->use_quads = (glamor_priv->gl_flavor == GLAMOR_GL_DESKTOP) &&

glamor/glamor_copy.c

@@ -351,6 +351,9 @@ glamor_copy_fbo_fbo_draw(DrawablePtr src,
     if (!glamor_set_alu(screen, gc ? gc->alu : GXcopy))
         goto bail_ctx;
 
+    if (bitplane && !glamor_priv->can_copyplane)
+        goto bail_ctx;
+
     if (bitplane) {
         prog = &glamor_priv->copy_plane_prog;
         copy_facet = &glamor_facet_copyplane;

glamor/glamor_priv.h

@@ -201,6 +201,7 @@ typedef struct glamor_screen_private {
     Bool has_dual_blend;
     Bool has_texture_swizzle;
     Bool is_core_profile;
+    Bool can_copyplane;
     int max_fbo_size;
 
     GLuint one_channel_format;