[PATCH v5 5/6] drm/ast: Add drm_panic support

[Jocelyn Falempe <jfalempe@xxxxxxxxxx>]

Add support for the drm_panic module, which displays a message to
the screen when a kernel panic occurs.

Signed-off-by: Jocelyn Falempe <jfalempe@xxxxxxxxxx>
---
 drivers/gpu/drm/ast/ast_drv.c  |  4 ++--
 drivers/gpu/drm/ast/ast_drv.h  |  3 +++
 drivers/gpu/drm/ast/ast_mode.c | 26 ++++++++++++++++++++++++++
 3 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/ast/ast_drv.c b/drivers/gpu/drm/ast/ast_drv.c
index e1224ef4ad83..da60d2e237f5 100644
--- a/drivers/gpu/drm/ast/ast_drv.c
+++ b/drivers/gpu/drm/ast/ast_drv.c
@@ -62,8 +62,8 @@ static const struct drm_driver ast_driver = {
 	.major = DRIVER_MAJOR,
 	.minor = DRIVER_MINOR,
 	.patchlevel = DRIVER_PATCHLEVEL,
-
-	DRM_GEM_SHMEM_DRIVER_OPS
+	.get_scanout_buffer = ast_get_scanout_buffer,
+	DRM_GEM_SHMEM_DRIVER_OPS,
 };
 
 /*
diff --git a/drivers/gpu/drm/ast/ast_drv.h b/drivers/gpu/drm/ast/ast_drv.h
index 848a9f1403e8..b9c62d18e14e 100644
--- a/drivers/gpu/drm/ast/ast_drv.h
+++ b/drivers/gpu/drm/ast/ast_drv.h
@@ -504,6 +504,9 @@ int ast_mode_config_init(struct ast_device *ast);
 #define ASTDP_1366x768_60		0x1E
 #define ASTDP_1152x864_75		0x1F
 
+int ast_get_scanout_buffer(struct drm_device *dev,
+			   struct drm_scanout_buffer *sb);
+
 int ast_mm_init(struct ast_device *ast);
 
 /* ast post */
diff --git a/drivers/gpu/drm/ast/ast_mode.c b/drivers/gpu/drm/ast/ast_mode.c
index 32f04ec6c386..3653e65a135b 100644
--- a/drivers/gpu/drm/ast/ast_mode.c
+++ b/drivers/gpu/drm/ast/ast_mode.c
@@ -43,6 +43,7 @@
 #include <drm/drm_gem_framebuffer_helper.h>
 #include <drm/drm_gem_shmem_helper.h>
 #include <drm/drm_managed.h>
+#include <drm/drm_panic.h>
 #include <drm/drm_probe_helper.h>
 #include <drm/drm_simple_kms_helper.h>
 
@@ -1930,3 +1931,28 @@ int ast_mode_config_init(struct ast_device *ast)
 
 	return 0;
 }
+
+int ast_get_scanout_buffer(struct drm_device *dev,
+			   struct drm_scanout_buffer *sb)
+{
+	struct drm_plane *plane;
+	struct ast_plane *ast_plane;
+	struct iosys_map map;
+
+	drm_for_each_plane(plane, dev) {
+		if (!plane->state || !plane->state->visible || !plane->state->fb ||
+		    plane->type != DRM_PLANE_TYPE_PRIMARY)
+			continue;
+		ast_plane = to_ast_plane(plane);
+		if (!ast_plane->vaddr)
+			continue;
+
+		sb->format = plane->state->fb->format;
+		sb->width = plane->state->fb->width;
+		sb->height = plane->state->fb->height;
+		sb->pitch = plane->state->fb->pitches[0];
+		iosys_map_set_vaddr_iomem(&sb->map, ast_plane->vaddr);
+		return 0;
+	}
+	return -ENODEV;
+}
-- 
2.41.0