Add kunit tests for drm_panic.
They check that drawing the panic screen doesn't crash, but they
don't check the correctness of the resulting image.
Signed-off-by: Jocelyn Falempe <jfale...@redhat.com>
---
v2:
* Add a few checks, and more comments in the kunit tests. (Maxime Ripard).
MAINTAINERS | 1 +
drivers/gpu/drm/drm_panic.c | 4 +
drivers/gpu/drm/tests/drm_panic_test.c | 198 +++++++++++++++++++++++++
3 files changed, 203 insertions(+)
create mode 100644 drivers/gpu/drm/tests/drm_panic_test.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 402fe14091f1..e9be893d6741 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8480,6 +8480,7 @@ T: git
https://gitlab.freedesktop.org/drm/misc/kernel.git
F: drivers/gpu/drm/drm_draw.c
F: drivers/gpu/drm/drm_draw_internal.h
F: drivers/gpu/drm/drm_panic*.c
+F: drivers/gpu/drm/tests/drm_panic_test.c
F: include/drm/drm_panic*
DRM PANIC QR CODE
diff --git a/drivers/gpu/drm/drm_panic.c b/drivers/gpu/drm/drm_panic.c
index 1e06e3a18d09..d89812ff1935 100644
--- a/drivers/gpu/drm/drm_panic.c
+++ b/drivers/gpu/drm/drm_panic.c
@@ -986,3 +986,7 @@ void drm_panic_exit(void)
{
drm_panic_qr_exit();
}
+
+#ifdef CONFIG_DRM_KUNIT_TEST
+#include "tests/drm_panic_test.c"
+#endif
diff --git a/drivers/gpu/drm/tests/drm_panic_test.c
b/drivers/gpu/drm/tests/drm_panic_test.c
new file mode 100644
index 000000000000..d5d20dd2aa7c
--- /dev/null
+++ b/drivers/gpu/drm/tests/drm_panic_test.c
@@ -0,0 +1,198 @@
+// SPDX-License-Identifier: GPL-2.0 or MIT
+/*
+ * Copyright (c) 2025 Red Hat.
+ * Author: Jocelyn Falempe <jfale...@redhat.com>
+ *
+ * KUNIT tests for drm panic
+ */
+
+#include <drm/drm_fourcc.h>
+#include <drm/drm_panic.h>
+
+#include <kunit/test.h>
+
+#include <linux/units.h>
+#include <linux/vmalloc.h>
+
+/* Check the framebuffer color only if the panic colors are the default */
+#if (CONFIG_DRM_PANIC_BACKGROUND_COLOR == 0 && \
+ CONFIG_DRM_PANIC_FOREGROUND_COLOR == 0xffffff)
+#define DRM_PANIC_CHECK_COLOR
+#endif
+
+struct drm_test_mode {
+ const int width;
+ const int height;
+ const u32 format;
+ void (*draw_screen)(struct drm_scanout_buffer *sb);
+ const char *fname;
+};
+
+/*
+ * Run all tests for the 3 panic screens: user, kmsg and qr_code
+ */
+#define DRM_TEST_MODE_LIST(func) \
+ DRM_PANIC_TEST_MODE(1024, 768, DRM_FORMAT_XRGB8888, func) \
+ DRM_PANIC_TEST_MODE(300, 200, DRM_FORMAT_XRGB8888, func) \
+ DRM_PANIC_TEST_MODE(1920, 1080, DRM_FORMAT_XRGB8888, func) \
+ DRM_PANIC_TEST_MODE(1024, 768, DRM_FORMAT_RGB565, func) \
+ DRM_PANIC_TEST_MODE(1024, 768, DRM_FORMAT_RGB888, func) \
+
+#define DRM_PANIC_TEST_MODE(w, h, f, name) { \
+ .width = w, \
+ .height = h, \
+ .format = f, \
+ .draw_screen = draw_panic_screen_##name, \
+ .fname = #name, \
+ }, \
+
+static const struct drm_test_mode drm_test_modes_cases[] = {
+ DRM_TEST_MODE_LIST(user)
+ DRM_TEST_MODE_LIST(kmsg)
+ DRM_TEST_MODE_LIST(qr_code)
+};
+#undef DRM_PANIC_TEST_MODE
+
+static int drm_test_panic_init(struct kunit *test)
+{
+ struct drm_scanout_buffer *priv;
+
+ priv = kunit_kzalloc(test, sizeof(*priv), GFP_KERNEL);
+ KUNIT_ASSERT_NOT_NULL(test, priv);
+
+ test->priv = priv;
+
+ drm_panic_set_description("Kunit testing");
+
+ return 0;
+}
+
+/*
+ * Test drawing the panic screen, using a memory mapped framebuffer
+ * Set the whole buffer to 0xa5, and then check that all pixels have been
+ * written.
+ */
+static void drm_test_panic_screen_user_map(struct kunit *test)
+{
+ struct drm_scanout_buffer *sb = test->priv;
+ const struct drm_test_mode *params = test->param_value;
+ char *fb;
+ int fb_size;
+
+ sb->format = drm_format_info(params->format);
+ fb_size = params->width * params->height * sb->format->cpp[0];
+
+ fb = vmalloc(fb_size);
+ KUNIT_ASSERT_NOT_NULL(test, fb);
+
+ memset(fb, 0xa5, fb_size);
+
+ iosys_map_set_vaddr(&sb->map[0], fb);
+ sb->width = params->width;
+ sb->height = params->height;
+ sb->pitch[0] = params->width * sb->format->cpp[0];
+
+ params->draw_screen(sb);
+
+#ifdef DRM_PANIC_CHECK_COLOR
+ {
+ int i;
+
+ for (i = 0; i < fb_size; i++)
+ KUNIT_ASSERT_TRUE(test, fb[i] == 0 || fb[i] == 0xff);
+ }
+#endif
