egl: Remove the 565 pbuffer-only EGL config under X11.

The CTS finally has agreed to drop the requirement for a
565-no-depth-no-stencil config for ES 3.0. Hence we can now remove the
code to satisfy this requirement using a pbuffer-only visual with
whatever other buffers the driver happens to have given us.

This reverts commit 82607f8a900796871470ac4f1a04e154392e4898,
commit 6ad31c4ff33d92f6359b196a94ace99682272111 and
commit dacb11a585face5ca179c34cfc588a71a425c1e0.

v2:
  - Reference the VK-GL-CTS issue (Eric E.).

v3:
  - Don't revert
    fc21394bc4d ("egl: Quiet warning about front buffer rendering for pixmaps/pbuffers")
    (Kenneth).

References: VK-GL-CTS issue 1601.
Cc: mesa-stable@lists.freedesktop.org
Signed-off-by: Andres Gomez <agomez@igalia.com>
Acked-by: Eric Engestrom <eric.engestrom@intel.com>
Acked-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
(cherry picked from commit 02c265be9dcc5c5c23123e716ef62b384540d2fa)
[Juan A. Suarez: resolve trivial conflicts]
Signed-off-by: Juan A. Suarez Romero <jasuarez@igalia.com>

Conflicts:
	src/egl/drivers/dri2/platform_x11.c

1 files changed, 4 insertions, 97 deletions

diff --git a/src/egl/drivers/dri2/platform_x11.c b/src/egl/drivers/dri2/platform_x11.c
index b73e1970595..2b3842881ba 100644
--- a/src/egl/drivers/dri2/platform_x11.c
+++ b/src/egl/drivers/dri2/platform_x11.c
@@ -753,61 +753,9 @@ dri2_x11_authenticate(_EGLDisplay *disp, uint32_t id)
    return dri2_x11_do_authenticate(dri2_dpy, id);
 }
 
-static bool
-dri2_x11_config_match_attrib(struct dri2_egl_display *dri2_dpy,
-                             const __DRIconfig *config,
-                             unsigned int attrib,
-                             unsigned int value)
-{
-   uint32_t config_val;
-   if (!dri2_dpy->core->getConfigAttrib(config, attrib, &config_val))
-      return false;
-   return config_val == value;
-}
-
-/**
- * See if the X server can export a pixmap with the given color depth.
- *
- * Glamor in xorg-server 1.20 can't export pixmaps which have a different
- * color depth than the root window as a DRI image.  This makes it impossible
- * to expose pbuffer-only visuals with, say, 16bpp on a 24bpp X display.
- */
-static bool
-x11_can_export_pixmap_with_bpp(struct dri2_egl_display *dri2_dpy, int bpp)
-{
-   bool supported = false;
-
-#ifdef HAVE_DRI3
-   xcb_dri3_buffer_from_pixmap_cookie_t cookie;
-   xcb_dri3_buffer_from_pixmap_reply_t *reply;
-
-   xcb_pixmap_t pixmap = xcb_generate_id(dri2_dpy->conn);
-   xcb_create_pixmap(dri2_dpy->conn, bpp, pixmap, dri2_dpy->screen->root, 1, 1);
-   cookie = xcb_dri3_buffer_from_pixmap(dri2_dpy->conn, pixmap);
-   reply = xcb_dri3_buffer_from_pixmap_reply(dri2_dpy->conn, cookie, NULL);
-
-   if (reply) {
-      int *fds = xcb_dri3_buffer_from_pixmap_reply_fds(dri2_dpy->conn, reply);
-
-      for (int i = 0; i < reply->nfd; i++) {
-         close(fds[i]);
-      }
-
-      supported = true;
-
-      free(reply);
-   }
-
-   xcb_free_pixmap(dri2_dpy->conn, pixmap);
-#endif
-
-   return supported;
-}
-
 static EGLBoolean
 dri2_x11_add_configs_for_visuals(struct dri2_egl_display *dri2_dpy,
-                                 _EGLDisplay *disp, bool supports_preserved,
-                                 bool add_pbuffer_configs)
+                                 _EGLDisplay *disp, bool supports_preserved)
 {
    xcb_depth_iterator_t d;
    xcb_visualtype_t *visuals;
@@ -883,47 +831,6 @@ dri2_x11_add_configs_for_visuals(struct dri2_egl_display *dri2_dpy,
       xcb_depth_next(&d);
    }
 
-   /* Add a 565-no-depth-no-stencil pbuffer-only config.  If X11 is depth 24,
-    * we wouldn't have 565 available, which the CTS demands.
-    */
-   if (add_pbuffer_configs && x11_can_export_pixmap_with_bpp(dri2_dpy, 16)) {
-      for (int j = 0; dri2_dpy->driver_configs[j]; j++) {
-         const __DRIconfig *config = dri2_dpy->driver_configs[j];
-         const EGLint config_attrs[] = {
-            EGL_NATIVE_VISUAL_ID,    0,
-            EGL_NATIVE_VISUAL_TYPE,  EGL_NONE,
-            EGL_NONE
-         };
-         EGLint surface_type = EGL_PBUFFER_BIT;
-         unsigned int rgba_masks[4] = {
-            0x1f << 11,
-            0x3f << 5,
-            0x1f << 0,
-            0,
-         };
-
-         /* Check that we've found single-sample, no depth, no stencil,
-          * and single-buffered.
-          */
-         if (!dri2_x11_config_match_attrib(dri2_dpy, config,
-                                           __DRI_ATTRIB_DEPTH_SIZE, 0) ||
-             !dri2_x11_config_match_attrib(dri2_dpy, config,
-                                           __DRI_ATTRIB_STENCIL_SIZE, 0) ||
-             !dri2_x11_config_match_attrib(dri2_dpy, config,
-                                           __DRI_ATTRIB_SAMPLES, 0) ||
-             !dri2_x11_config_match_attrib(dri2_dpy, config,
-                                           __DRI_ATTRIB_DOUBLE_BUFFER, 0)) {
-            continue;
-         }
-
-         if (dri2_add_config(disp, config, config_count + 1, surface_type,
-                             config_attrs, rgba_masks)) {
-            config_count++;
-            break;
-         }
-      }
-   }
-
    if (!config_count) {
       _eglLog(_EGL_WARNING, "DRI2: failed to create any config");
       return EGL_FALSE;
@@ -1388,7 +1295,7 @@ dri2_initialize_x11_swrast(_EGLDriver *drv, _EGLDisplay *disp)
 
    dri2_setup_screen(disp);
 
-   if (!dri2_x11_add_configs_for_visuals(dri2_dpy, disp, true, false))
+   if (!dri2_x11_add_configs_for_visuals(dri2_dpy, disp, true))
       goto cleanup;
 
    /* Fill vtbl last to prevent accidentally calling virtual function during
@@ -1486,7 +1393,7 @@ dri2_initialize_x11_dri3(_EGLDriver *drv, _EGLDisplay *disp)
 
    dri2_set_WL_bind_wayland_display(drv, disp);
 
-   if (!dri2_x11_add_configs_for_visuals(dri2_dpy, disp, false, true))
+   if (!dri2_x11_add_configs_for_visuals(dri2_dpy, disp, false))
       goto cleanup;
 
    dri2_dpy->loader_dri3_ext.core = dri2_dpy->core;
@@ -1596,7 +1503,7 @@ dri2_initialize_x11_dri2(_EGLDriver *drv, _EGLDisplay *disp)
 
    dri2_set_WL_bind_wayland_display(drv, disp);
 
-   if (!dri2_x11_add_configs_for_visuals(dri2_dpy, disp, true, false))
+   if (!dri2_x11_add_configs_for_visuals(dri2_dpy, disp, true))
       goto cleanup;
 
    /* Fill vtbl last to prevent accidentally calling virtual function during