1 files changed, 80 insertions, 0 deletions
diff --git a/drivers/gpu/drm/xe/display/xe_panic.c b/drivers/gpu/drm/xe/display/xe_panic.c
new file mode 100644
index 000000000000..f32b23338331
--- /dev/null
+++ b/drivers/gpu/drm/xe/display/xe_panic.c
@@ -0,0 +1,80 @@
+// SPDX-License-Identifier: MIT
+/* Copyright © 2025 Intel Corporation */
+
+#include <drm/drm_cache.h>
+#include <drm/drm_panic.h>
+
+#include "intel_display_types.h"
+#include "intel_fb.h"
+#include "intel_panic.h"
+#include "xe_bo.h"
+
+struct intel_panic {
+	struct page **pages;
+	int page;
+	void *vaddr;
+};
+
+static void xe_panic_kunmap(struct intel_panic *panic)
+{
+	if (panic->vaddr) {
+		drm_clflush_virt_range(panic->vaddr, PAGE_SIZE);
+		kunmap_local(panic->vaddr);
+		panic->vaddr = NULL;
+	}
+}
+
+/*
+ * The scanout buffer pages are not mapped, so for each pixel,
+ * use kmap_local_page_try_from_panic() to map the page, and write the pixel.
+ * Try to keep the map from the previous pixel, to avoid too much map/unmap.
+ */
+static void xe_panic_page_set_pixel(struct drm_scanout_buffer *sb, unsigned int x,
+				    unsigned int y, u32 color)
+{
+	struct intel_framebuffer *fb = (struct intel_framebuffer *)sb->private;
+	struct intel_panic *panic = fb->panic;
+	struct xe_bo *bo = gem_to_xe_bo(intel_fb_bo(&fb->base));
+	unsigned int new_page;
+	unsigned int offset;
+
+	if (fb->panic_tiling)
+		offset = fb->panic_tiling(sb->width, x, y);
+	else
+		offset = y * sb->pitch[0] + x * sb->format->cpp[0];
+
+	new_page = offset >> PAGE_SHIFT;
+	offset = offset % PAGE_SIZE;
+	if (new_page != panic->page) {
+		xe_panic_kunmap(panic);
+		panic->page = new_page;
+		panic->vaddr = ttm_bo_kmap_try_from_panic(&bo->ttm,
+							  panic->page);
+	}
+	if (panic->vaddr) {
+		u32 *pix = panic->vaddr + offset;
+		*pix = color;
+	}
+}
+
+struct intel_panic *intel_panic_alloc(void)
+{
+	struct intel_panic *panic;
+
+	panic = kzalloc(sizeof(*panic), GFP_KERNEL);
+
+	return panic;
+}
+
+int intel_panic_setup(struct intel_panic *panic, struct drm_scanout_buffer *sb)
+{
+	panic->page = -1;
+	sb->set_pixel = xe_panic_page_set_pixel;
+	return 0;
+}
+
+void intel_panic_finish(struct intel_panic *panic)
+{
+	xe_panic_kunmap(panic);
+	panic->page = -1;
+}