drm/vc4: tests: Introduce a test for LBM buffer size

The BCM2712 comes with a different LBM size computation than the previous generations, so let's add the few examples provided as kunit tests to make sure we always satisfy those requirements. Signed-off-by: Maxime Ripard <maxime@cerno.tech>
raspberrypi · gordoste · Aug 7, 2024 · Aug 28, 2024 · May 24, 2024 · Jun 27, 2024
commit 3825fc9c61d7bc655327c2afeb1dfe210d5558a2
diff --git a/drivers/gpu/drm/vc4/Makefile b/drivers/gpu/drm/vc4/Makefile
@@ -31,7 +31,8 @@ vc4-$(CONFIG_DRM_VC4_KUNIT_TEST) += \
 	tests/vc4_mock_crtc.o \
 	tests/vc4_mock_output.o \
 	tests/vc4_mock_plane.o \
-	tests/vc4_test_pv_muxing.o
+	tests/vc4_test_pv_muxing.o \
+	tests/vc4_test_lbm_size.o
 
 vc4-$(CONFIG_DEBUG_FS) += vc4_debugfs.o
 

diff --git a/drivers/gpu/drm/vc4/tests/vc4_test_lbm_size.c b/drivers/gpu/drm/vc4/tests/vc4_test_lbm_size.c
@@ -0,0 +1,308 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_atomic_uapi.h>
+#include <drm/drm_drv.h>
+#include <drm/drm_fourcc.h>
+#include <drm/drm_framebuffer.h>
+#include <drm/drm_plane.h>
+#include <drm/drm_kunit_helpers.h>
+
+#include "../../drm_crtc_internal.h"
+#include "../../drm_internal.h"
+
+#include <kunit/test.h>
+
+#include "../vc4_drv.h"
+
+#include "vc4_mock.h"
+
+u32 vc4_lbm_size(struct drm_plane_state *state);
+
+struct vc4_lbm_size_priv {
+	struct vc4_dev *vc4;
+	struct drm_file *file;
+	struct drm_modeset_acquire_ctx ctx;
+	struct drm_atomic_state *state;
+};
+
+struct vc4_lbm_size_param {
+	unsigned int src_w, src_h;
+	unsigned int crtc_w, crtc_h;
+	bool forced_alpha;
+	u32 fourcc;
+	enum vc4_scaling_mode expected_x_scaling[2];
+	enum vc4_scaling_mode expected_y_scaling[2];
+	unsigned int expected_lbm_size;
+};
+
+static const struct vc4_lbm_size_param vc4_test_lbm_size_params[] = {
+	{
+		.src_w = 256,
+		.crtc_w = 256,
+		.src_h = 256,
+		.crtc_h = 512,
+		.fourcc = DRM_FORMAT_ARGB8888,
+		.expected_x_scaling = { VC4_SCALING_NONE, },
+		.expected_y_scaling = { VC4_SCALING_PPF, },
+		.expected_lbm_size = 32,
+	},
+	{
+		.src_w = 256,
+		.crtc_w = 179,
+		.src_h = 256,
+		.crtc_h = 512,
+		.fourcc = DRM_FORMAT_ARGB8888,
+		.expected_x_scaling = { VC4_SCALING_PPF, },
+		.expected_y_scaling = { VC4_SCALING_PPF, },
+		.expected_lbm_size = 23,
+	},
+	{
+		.src_w = 256,
+		.crtc_w = 256,
+		.src_h = 256,
+		.crtc_h = 512,
+		.fourcc = DRM_FORMAT_XRGB8888,
+		.expected_x_scaling = { VC4_SCALING_NONE, },
+		.expected_y_scaling = { VC4_SCALING_PPF, },
+		.expected_lbm_size = 24,
+	},
+	{
+		.src_w = 100,
+		.crtc_w = 73,
+		.src_h = 100,
+		.crtc_h = 73,
+		.fourcc = DRM_FORMAT_XRGB8888,
+		.expected_x_scaling = { VC4_SCALING_PPF, },
+		.expected_y_scaling = { VC4_SCALING_PPF, },
+		.expected_lbm_size = 8,
+	},
+	{
+		.src_w = 256,
+		.crtc_w = 256,
+		.src_h = 256,
+		.crtc_h = 512,
+		.forced_alpha = true,
+		.fourcc = DRM_FORMAT_ARGB8888,
+		.expected_x_scaling = { VC4_SCALING_NONE, },
+		.expected_y_scaling = { VC4_SCALING_PPF, },
+		.expected_lbm_size = 24,
+	},
+	{
+		.src_w = 100,
+		.crtc_w = 73,
+		.src_h = 100,
+		.crtc_h = 73,
+		.forced_alpha = true,
+		.fourcc = DRM_FORMAT_ARGB8888,
+		.expected_x_scaling = { VC4_SCALING_PPF, },
+		.expected_y_scaling = { VC4_SCALING_PPF, },
+		.expected_lbm_size = 8,
+	},
+	{
+		.src_w = 256,
+		.crtc_w = 94,
+		.src_h = 256,
+		.crtc_h = 94,
+		.fourcc = DRM_FORMAT_ARGB8888,
+		.expected_x_scaling = { VC4_SCALING_TPZ, },
+		.expected_y_scaling = { VC4_SCALING_TPZ, },
+		.expected_lbm_size = 6,
+	},
+
+/*
+ * TODO: Those tests reflect the LBM size calculation examples, but the
+ * driver ends up taking different scaler filters decisions, and thus
+ * doesn't end up with the same sizes. It would be valuable to have
+ * those tests, but the driver doesn't take a bad decision either, so
+ * it's not clear what we should do at this point.
+ */
+#if 0
+	{
+		.src_w = 320,
+		.crtc_w = 320,
+		.src_h = 320,
+		.crtc_h = 320,
+		.fourcc = DRM_FORMAT_YUV420,
+		.expected_x_scaling = { VC4_SCALING_NONE, VC4_SCALING_NONE, },
+		.expected_y_scaling = { VC4_SCALING_NONE, VC4_SCALING_PPF, },
+		.expected_lbm_size = 10,
+	},
+	{
+		.src_w = 512,
+		.crtc_w = 512,
+		.src_h = 512,
+		.crtc_h = 256,
+		.fourcc = DRM_FORMAT_YUV420,
+		.expected_x_scaling = { VC4_SCALING_NONE, VC4_SCALING_NONE, },
+		.expected_y_scaling = { VC4_SCALING_TPZ, VC4_SCALING_NONE, },
+		.expected_lbm_size = 5,
+	},
+	{
+		.src_w = 486,
+		.crtc_w = 157,
+		.src_h = 404,
+		.crtc_h = 929,
+		.fourcc = DRM_FORMAT_YUV422,
+		.expected_x_scaling = { VC4_SCALING_PPF, VC4_SCALING_PPF, },
+		.expected_y_scaling = { VC4_SCALING_PPF, VC4_SCALING_PPF, },
+		.expected_lbm_size = 20,
+	},
+	{
+		.src_w = 320,
+		.crtc_w = 128,
+		.src_h = 176,
+		.crtc_h = 70,
+		.fourcc = DRM_FORMAT_YUV420,
+		.expected_x_scaling = { VC4_SCALING_TPZ, VC4_SCALING_TPZ, },
+		.expected_y_scaling = { VC4_SCALING_TPZ, VC4_SCALING_TPZ, },
+		.expected_lbm_size = 8,
+	},
+#endif
+};
+
+static void vc4_test_lbm_size_desc(const struct vc4_lbm_size_param *t, char *desc)
+{
+	snprintf(desc, KUNIT_PARAM_DESC_SIZE,
+		 "%ux%u to %ux%u %s(%p4cc)",
+		 t->src_w, t->src_h,
+		 t->crtc_w, t->crtc_h,
+		 t->forced_alpha ? "with forced alpha " : "",
+		 &t->fourcc);
+}
+
+KUNIT_ARRAY_PARAM(vc4_test_lbm_size,
+		  vc4_test_lbm_size_params,
+		  vc4_test_lbm_size_desc);
+
+static void drm_vc4_test_vc4_lbm_size(struct kunit *test)
+{
+	const struct vc4_lbm_size_param *params = test->param_value;
+	const struct vc4_lbm_size_priv *priv = test->priv;
+	const struct drm_format_info *info;
+	struct drm_mode_fb_cmd2 fb_req = { };
+	struct drm_atomic_state *state = priv->state;
+	struct vc4_plane_state *vc4_plane_state;
+	struct drm_plane_state *plane_state;
+	struct vc4_dummy_output *output;
+	struct drm_framebuffer *fb;
+	struct drm_plane *plane;
+	struct drm_crtc *crtc;
+	unsigned int i;
+	int ret;
+
+	info = drm_format_info(params->fourcc);
+	KUNIT_ASSERT_NOT_NULL(test, info);
+
+	output = vc4_mock_atomic_add_output(test, state, VC4_ENCODER_TYPE_HDMI0);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, output);
+
+	crtc = vc4_find_crtc_for_encoder(test, &output->encoder.base);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, crtc);
+
+	plane = vc4_mock_atomic_add_plane(test, state, crtc);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, plane);
+
+	plane_state = drm_atomic_get_plane_state(state, plane);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, plane_state);
+
+	vc4_plane_state = to_vc4_plane_state(plane_state);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, vc4_plane_state);
+
+	fb_req.pixel_format = params->fourcc;
+	fb_req.width = params->src_w;
+	fb_req.height = params->src_h;
+
+	for (i = 0; i < info->num_planes; i++) {
+		struct drm_mode_create_dumb dumb_args = { };
+
+		dumb_args.width = params->src_w;
+		dumb_args.height = params->src_h;
+		dumb_args.bpp = drm_format_info_bpp(info, i);
+
+		ret = drm_mode_create_dumb(state->dev, &dumb_args, priv->file);
+		KUNIT_ASSERT_EQ(test, ret, 0);
+
+		fb_req.handles[i] = dumb_args.handle;
+		fb_req.pitches[i] = dumb_args.pitch;
+	}
+
+	fb = drm_internal_framebuffer_create(state->dev, &fb_req, priv->file);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, fb);
+
+	drm_atomic_set_fb_for_plane(plane_state, fb);
+
+	plane_state->src_x = 0;
+	plane_state->src_y = 0;
+	plane_state->src_h = params->src_h << 16;
+	plane_state->src_w = params->src_w << 16;
+
+	plane_state->crtc_x = 0;
+	plane_state->crtc_y = 0;
+	plane_state->crtc_h = params->crtc_h;
+	plane_state->crtc_w = params->crtc_w;
+
+	if (params->forced_alpha)
+		plane_state->alpha = 128;
+
+	ret = drm_atomic_check_only(state);
+	KUNIT_ASSERT_EQ(test, ret, 0);
+
+	KUNIT_EXPECT_EQ(test, vc4_plane_state->lbm.size, params->expected_lbm_size);
+
+	for (i = 0; i < 2; i++) {
+		KUNIT_EXPECT_EQ(test,
+				vc4_plane_state->x_scaling[i],
+				params->expected_x_scaling[i]);
+		KUNIT_EXPECT_EQ(test,
+				vc4_plane_state->y_scaling[i],
+				params->expected_y_scaling[i]);
+	}
+
+	drm_framebuffer_put(fb);
+
+	for (i = 0; i < info->num_planes; i++)
+		drm_mode_destroy_dumb(state->dev, fb_req.handles[i], priv->file);
+}
+
+static struct kunit_case vc4_lbm_size_tests[] = {
+	KUNIT_CASE_PARAM(drm_vc4_test_vc4_lbm_size,
+			 vc4_test_lbm_size_gen_params),
+	{}
+};
+
+static int vc4_lbm_size_test_init(struct kunit *test)
+{
+	struct drm_modeset_acquire_ctx *ctx;
+	struct vc4_lbm_size_priv *priv;
+	struct drm_device *drm;
+	struct vc4_dev *vc4;
+
+	priv = kunit_kzalloc(test, sizeof(*priv), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, priv);
+	test->priv = priv;
+
+	vc4 = vc6_mock_device(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, vc4);
+	priv->vc4 = vc4;
+
+	priv->file = drm_file_alloc(priv->vc4->base.primary);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, priv->file);
+
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
+	drm = &vc4->base;
+	priv->state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, priv->state);
+
+	return 0;
+}
+
+static struct kunit_suite vc4_lbm_size_test_suite = {
+	.name = "vc4-lbm-size",
+	.init = vc4_lbm_size_test_init,
+	.test_cases = vc4_lbm_size_tests,
+};
+
+kunit_test_suite(vc4_lbm_size_test_suite);
diff --git a/drivers/gpu/drm/vc4/tests/vc4_test_pv_muxing.c b/drivers/gpu/drm/vc4/tests/vc4_test_pv_muxing.c
@@ -853,7 +853,6 @@ static struct kunit_case vc6_pv_muxing_tests[] = {
 static struct kunit_suite vc6_pv_muxing_test_suite = {
 	.name = "vc6-pv-muxing-combinations",
 	.init = vc4_pv_muxing_test_init,
-	.exit = vc4_pv_muxing_test_exit,
 	.test_cases = vc6_pv_muxing_tests,
 };