backends: force enable modifiers on tagged devices

Some devices can't scanout to linear buffers directly as the hw is not
capable of eg rendering into a linear depth buffer.

Add code to force kms-modifiers on udev taged devices.

Closes: https://gitlab.gnome.org/GNOME/mutter/-/issues/1408

https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1443

data/61-mutter.rules

@@ -0,0 +1 @@
+DRIVER=="tegra-host1x", SUBSYSTEM=="platform", TAG+="mutter-device-requires-kms-modifiers"

data/meson.build

@@ -58,3 +58,9 @@ configure_file(
 install_data(['mutter-schemas.convert'],
   install_dir: join_paths(datadir, 'GConf/gsettings'),
 )
+
+if have_libgudev
+  install_data(['61-mutter.rules'],
+    install_dir: join_paths(udevdir, 'rules.d'),
+  )
+endif

meson.build

@@ -182,6 +182,8 @@ have_libgudev = get_option('udev')
 if have_libgudev
   libudev_dep = dependency('libudev', version: udev_req)
   gudev_dep = dependency('gudev-1.0', version: gudev_req)
+  udev_dep = dependency('udev')
+  udevdir = udev_dep.get_pkgconfig_variable('udevdir')
 endif
 
 have_native_backend = get_option('native_backend')

src/backends/native/meta-backend-native.c

@@ -571,6 +571,9 @@ create_gpu_from_udev_device (MetaBackendNative  *native,
   if (meta_is_udev_device_boot_vga (device))
     flags |= META_KMS_DEVICE_FLAG_BOOT_VGA;
 
+  if (meta_is_udev_device_requires_modifiers (device))
+    flags |= META_KMS_DEVICE_FLAG_REQUIRES_MODIFIERS;
+
   device_path = g_udev_device_get_device_file (device);
 
   kms_device = meta_kms_create_device (native->kms, device_path, flags,

src/backends/native/meta-gpu-kms.c

@@ -266,6 +266,15 @@ meta_gpu_kms_is_platform_device (MetaGpuKms *gpu_kms)
   return !!(flags & META_KMS_DEVICE_FLAG_PLATFORM_DEVICE);
 }
 
+gboolean
+meta_gpu_kms_requires_modifiers (MetaGpuKms *gpu_kms)
+{
+  MetaKmsDeviceFlag flags;
+
+  flags = meta_kms_device_get_flags (gpu_kms->kms_device);
+  return !!(flags & META_KMS_DEVICE_FLAG_REQUIRES_MODIFIERS);
+}
+
 static int
 compare_outputs (gconstpointer one,
                  gconstpointer two)

src/backends/native/meta-gpu-kms.h

@@ -47,6 +47,7 @@ gboolean meta_gpu_kms_is_crtc_active (MetaGpuKms *gpu_kms,
 
 gboolean meta_gpu_kms_is_boot_vga (MetaGpuKms *gpu_kms);
 gboolean meta_gpu_kms_is_platform_device (MetaGpuKms *gpu_kms);
+gboolean meta_gpu_kms_requires_modifiers (MetaGpuKms *gpu_kms);
 
 MetaKmsDevice * meta_gpu_kms_get_kms_device (MetaGpuKms *gpu_kms);
 

src/backends/native/meta-kms-types.h

@@ -56,6 +56,7 @@ typedef enum _MetaKmsDeviceFlag
   META_KMS_DEVICE_FLAG_NONE = 0,
   META_KMS_DEVICE_FLAG_BOOT_VGA = 1 << 0,
   META_KMS_DEVICE_FLAG_PLATFORM_DEVICE = 1 << 1,
+  META_KMS_DEVICE_FLAG_REQUIRES_MODIFIERS = 1 << 2,
 } MetaKmsDeviceFlag;
 
 typedef enum _MetaKmsPlaneType MetaKmsPlaneType;

src/backends/native/meta-renderer-native.c

@@ -320,6 +320,12 @@ meta_renderer_native_get_egl (MetaRendererNative *renderer_native)
   return meta_backend_get_egl (meta_renderer_get_backend (renderer));
 }
 
+gboolean
+meta_renderer_native_use_modifiers (MetaRendererNative *renderer_native)
+{
+  return renderer_native->use_modifiers;
+}
+
 static MetaEgl *
 meta_onscreen_native_get_egl (MetaOnscreenNative *onscreen_native)
 {
@@ -3804,6 +3810,9 @@ meta_renderer_native_initable_init (GInitable     *initable,
   if (!renderer_native->primary_gpu_kms)
     return FALSE;
 
+  if (meta_gpu_kms_requires_modifiers (renderer_native->primary_gpu_kms))
+    renderer_native->use_modifiers = TRUE;
+
   return TRUE;
 }
 

src/backends/native/meta-renderer-native.h

@@ -55,6 +55,8 @@ MetaGpuKms * meta_renderer_native_get_primary_gpu (MetaRendererNative *renderer_
 
 void meta_renderer_native_finish_frame (MetaRendererNative *renderer_native);
 
+gboolean meta_renderer_native_use_modifiers (MetaRendererNative *renderer_native);
+
 gboolean meta_onscreen_native_is_buffer_scanout_compatible (CoglOnscreen *onscreen,
                                                             uint32_t      drm_format,
                                                             uint64_t      drm_modifier,

src/backends/native/meta-udev.c

@@ -74,6 +74,27 @@ meta_is_udev_device_boot_vga (GUdevDevice *device)
   return g_udev_device_get_sysfs_attr_as_int (pci_device, "boot_vga") == 1;
 }
 
+gboolean
+meta_is_udev_device_requires_modifiers (GUdevDevice *device)
+{
+  g_autoptr (GUdevDevice) platform_device = NULL;
+  const char * const * tags;
+
+  platform_device = g_udev_device_get_parent_with_subsystem (device,
+                                                             "platform",
+                                                             NULL);
+
+  if (!platform_device)
+    return FALSE;
+
+  tags = g_udev_device_get_tags (platform_device);
+
+  if (!tags)
+    return FALSE;
+
+  return g_strv_contains (tags, "mutter-device-requires-kms-modifiers");
+}
+
 gboolean
 meta_udev_is_drm_device (MetaUdev    *udev,
                          GUdevDevice *device)

src/backends/native/meta-udev.h

@@ -32,6 +32,8 @@ gboolean meta_is_udev_device_platform_device (GUdevDevice *device);
 
 gboolean meta_is_udev_device_boot_vga (GUdevDevice *device);
 
+gboolean meta_is_udev_device_requires_modifiers (GUdevDevice *device);
+
 gboolean meta_udev_is_drm_device (MetaUdev    *udev,
                                   GUdevDevice *device);
 

src/wayland/meta-wayland-dma-buf.c

@@ -594,6 +594,15 @@ should_send_modifiers (MetaBackend *backend)
 {
   MetaSettings *settings = meta_backend_get_settings (backend);
 
+#ifdef HAVE_NATIVE_BACKEND
+  if (META_IS_BACKEND_NATIVE (backend))
+    {
+      MetaRenderer *renderer = meta_backend_get_renderer (backend);
+      MetaRendererNative *renderer_native = META_RENDERER_NATIVE (renderer);
+      return meta_renderer_native_use_modifiers (renderer_native);
+    }
+#endif
+
   return meta_settings_is_experimental_feature_enabled (
            settings, META_EXPERIMENTAL_FEATURE_KMS_MODIFIERS);
 }