Re: [PATCH RFC drm-misc-next v2 1/1] drm/hyperv: Add support for drm_panic

[Jocelyn Falempe]

On 26/05/2025 11:01, Ryosuke Yasuoka wrote:

Add drm_panic module for hyperv drm so that panic screen can be
displayed on panic.

Thanks, it looks good to me.

Reviewed-by: Jocelyn Falempe <jfale...@redhat.com>

Signed-off-by: Ryosuke Yasuoka <ryasu...@redhat.com>
---
  drivers/gpu/drm/hyperv/hyperv_drm_modeset.c | 36 +++++++++++++++++++++
  1 file changed, 36 insertions(+)

diff --git a/drivers/gpu/drm/hyperv/hyperv_drm_modeset.c 
b/drivers/gpu/drm/hyperv/hyperv_drm_modeset.c
index f7d2e973f79e..945b9482bcb3 100644
--- a/drivers/gpu/drm/hyperv/hyperv_drm_modeset.c
+++ b/drivers/gpu/drm/hyperv/hyperv_drm_modeset.c
@@ -17,6 +17,7 @@
  #include <drm/drm_gem_framebuffer_helper.h>
  #include <drm/drm_gem_shmem_helper.h>
  #include <drm/drm_probe_helper.h>
+#include <drm/drm_panic.h>
  #include <drm/drm_plane.h>

#include "hyperv_drm.h"

@@ -181,10 +182,45 @@ static void hyperv_plane_atomic_update(struct drm_plane 
*plane,
        }
  }

+static int hyperv_plane_get_scanout_buffer(struct drm_plane *plane,

+                                          struct drm_scanout_buffer *sb)
+{
+       struct hyperv_drm_device *hv = to_hv(plane->dev);
+       struct iosys_map map = IOSYS_MAP_INIT_VADDR_IOMEM(hv->vram);
+
+       if (plane->state && plane->state->fb) {
+               sb->format = plane->state->fb->format;
+               sb->width = plane->state->fb->width;
+               sb->height = plane->state->fb->height;
+               sb->pitch[0] = plane->state->fb->pitches[0];
+               sb->map[0] = map;
+               return 0;
+       }
+       return -ENODEV;
+}
+
+static void hyperv_plane_panic_flush(struct drm_plane *plane)
+{
+       struct hyperv_drm_device *hv = to_hv(plane->dev);
+       struct drm_rect rect;
+
+       if (!plane->state || !plane->state->fb)
+               return;
+
+       rect.x1 = 0;
+       rect.y1 = 0;
+       rect.x2 = plane->state->fb->width;
+       rect.y2 = plane->state->fb->height;
+
+       hyperv_update_dirt(hv->hdev, &rect);
+}
+
  static const struct drm_plane_helper_funcs hyperv_plane_helper_funcs = {
        DRM_GEM_SHADOW_PLANE_HELPER_FUNCS,
        .atomic_check = hyperv_plane_atomic_check,
        .atomic_update = hyperv_plane_atomic_update,
+       .get_scanout_buffer = hyperv_plane_get_scanout_buffer,
+       .panic_flush = hyperv_plane_panic_flush,
  };

static const struct drm_plane_funcs hyperv_plane_funcs = {