plymouth/plymouth-only_use_fb_for_cirrus_bochs.patch

diff -Nura plymouth-0.9.5~git20220412.e960111/src/libply-splash-core/ply-device-manager.c plymouth-0.9.5~git20220412.e960111_new/src/libply-splash-core/ply-device-manager.c
--- plymouth-0.9.5~git20220412.e960111/src/libply-splash-core/ply-device-manager.c	2022-04-15 16:39:24.000000000 +0800
+++ plymouth-0.9.5~git20220412.e960111_new/src/libply-splash-core/ply-device-manager.c	2022-04-18 16:33:00.126364096 +0800
@@ -279,13 +279,33 @@
                 subsystem = udev_device_get_subsystem (device);
                 ply_trace ("device subsystem is %s", subsystem);
 
+                const char *card_vendor = udev_device_get_sysattr_value (device, "device/vendor");
+                const char *card_device = udev_device_get_sysattr_value (device, "device/device");
+                bool use_fb = false;
+                if (card_vendor) {
+                        /* Cirrus */
+                        if (strcmp ("0x1013", card_vendor) == 0)
+                                use_fb = true;
+                        /* "Technical Corp", also used by bochs */
+                        else if (strcmp ("0x1234", card_vendor) == 0)
+                                use_fb = strcmp("0x1111", card_device) == 0;
+                }
+
                 if (strcmp (subsystem, SUBSYSTEM_DRM) == 0) {
                         ply_trace ("found DRM device %s", device_path);
                         renderer_type = PLY_RENDERER_TYPE_DRM;
+                        if (use_fb) {
+                                ply_trace ("forcing use of framebuffer for cirrusdrmfb");
+                                renderer_type = PLY_RENDERER_TYPE_NONE;
+                        }
                 } else if (strcmp (subsystem, SUBSYSTEM_FRAME_BUFFER) == 0) {
                         ply_trace ("found frame buffer device %s", device_path);
-                        if (!fb_device_has_drm_device (manager, device))
+                        if (use_fb) {
                                 renderer_type = PLY_RENDERER_TYPE_FRAME_BUFFER;
+                        }
+                        else if (!fb_device_has_drm_device (manager, device)) {
+                                ply_trace ("avoiding use of framebuffer to not block DRM drivers from working");
+                        }
                         else
                                 ply_trace ("ignoring, since there's a DRM device associated with it");
                 }