Add unit test to the SubVP feature in order to avoid possible
regressions and assure the code robustness.

Signed-off-by: Maíra Canal <mairacanal@riseup.net>
---
 drivers/gpu/drm/amd/display/Kconfig           |  13 +
 drivers/gpu/drm/amd/display/dc/dc_dmub_srv.c  |   4 +
 .../gpu/drm/amd/display/tests/.kunitconfig    |   1 +
 .../amd/display/tests/dc/dc_dmub_srv_test.c   | 285 ++++++++++++++++++
 4 files changed, 303 insertions(+)
 create mode 100644 drivers/gpu/drm/amd/display/tests/dc/dc_dmub_srv_test.c

diff --git a/drivers/gpu/drm/amd/display/Kconfig b/drivers/gpu/drm/amd/display/Kconfig
index 039227baedfa..f667b954f89f 100644
--- a/drivers/gpu/drm/amd/display/Kconfig
+++ b/drivers/gpu/drm/amd/display/Kconfig
@@ -93,4 +93,17 @@ config AMD_DC_BASICS_KUNIT_TEST
 
 		If unsure, say N.
 
+config AMD_DC_KUNIT_TEST
+	bool "Enable KUnit tests for the 'utils' sub-component of DAL" if !KUNIT_ALL_TESTS
+	depends on DRM_AMD_DC && KUNIT
+	default KUNIT_ALL_TESTS
+	help
+		Enables unit tests for the basics folder of Display Core. Only useful for
+		kernel devs running KUnit.
+
+		For more information on KUnit and unit tests in general please refer to
+		the KUnit documentation in Documentation/dev-tools/kunit/.
+
+		If unsure, say N.
+
 endmenu
diff --git a/drivers/gpu/drm/amd/display/dc/dc_dmub_srv.c b/drivers/gpu/drm/amd/display/dc/dc_dmub_srv.c
index 7b765efe0825..2e8d5549a087 100644
--- a/drivers/gpu/drm/amd/display/dc/dc_dmub_srv.c
+++ b/drivers/gpu/drm/amd/display/dc/dc_dmub_srv.c
@@ -858,3 +858,7 @@ void dc_dmub_srv_log_diagnostic_data(struct dc_dmub_srv *dc_dmub_srv)
 		diag_data.is_cw0_enabled,
 		diag_data.is_cw6_enabled);
 }
+
+#if IS_ENABLED(CONFIG_AMD_DC_KUNIT_TEST)
+#include "../tests/dc/dc_dmub_srv_test.c"
+#endif
diff --git a/drivers/gpu/drm/amd/display/tests/.kunitconfig b/drivers/gpu/drm/amd/display/tests/.kunitconfig
index eb6f81601757..4c5861ad58bd 100644
--- a/drivers/gpu/drm/amd/display/tests/.kunitconfig
+++ b/drivers/gpu/drm/amd/display/tests/.kunitconfig
@@ -4,5 +4,6 @@ CONFIG_DRM=y
 CONFIG_DRM_AMDGPU=y
 CONFIG_DRM_AMD_DC=y
 CONFIG_AMD_DC_BASICS_KUNIT_TEST=y
+CONFIG_AMD_DC_KUNIT_TEST=y
 CONFIG_DCE_KUNIT_TEST=y
 CONFIG_DML_KUNIT_TEST=y
diff --git a/drivers/gpu/drm/amd/display/tests/dc/dc_dmub_srv_test.c b/drivers/gpu/drm/amd/display/tests/dc/dc_dmub_srv_test.c
new file mode 100644
index 000000000000..3f1f15397090
--- /dev/null
+++ b/drivers/gpu/drm/amd/display/tests/dc/dc_dmub_srv_test.c
@@ -0,0 +1,285 @@
+// SPDX-License-Identifier: MIT
+/*
+ * KUnit tests for dc_dmub_srv.c
+ *
+ * Copyright (C) 2022, Maíra Canal <mairacanal@riseup.net>
+ */
+
+#include <kunit/test.h>
+#include "dc_dmub_srv.h"
+
+struct populate_subvp_cmd_drr_info_test_case {
+	const char *desc;
+	struct dc *dc;
+	struct pipe_ctx *subvp_pipe;
+	struct pipe_ctx *vblank_pipe;
+	const u8 drr_in_use;
+	const u8 drr_window_size_ms;
+	const u16 min_vtotal_supported;
+	const u16 max_vtotal_supported;
+	const u8 use_ramping;
+};
+
+struct populate_subvp_cmd_drr_info_test_case populate_subvp_cmd_drr_info_cases[] = {
+	{
+		.desc = "Same Clock Frequency",
+		.dc = &(struct dc) {
+			.caps = {
+				.subvp_prefetch_end_to_mall_start_us = 0,
+			}
+		},
+		.subvp_pipe = &(struct pipe_ctx) {
+			.stream = &(struct dc_stream_state) {
+				.timing = {
+					.h_total = 2784,
+					.v_addressable = 1080,
+					.pix_clk_100hz = 1855800,
+				},
+				.mall_stream_config = {
+					.paired_stream = &(struct dc_stream_state) {
+						.timing = {
+							.h_total = 3600,
+							.v_total = 1111,
+							.v_addressable = 1080,
+							.v_front_porch = 3,
+							.pix_clk_100hz = 1855800,
+						},
+					},
+				},
+			},
+		},
+		.vblank_pipe = &(struct pipe_ctx) {
+			.stream = &(struct dc_stream_state) {
+				.timing = {
+					.h_total = 2784,
+					.v_total = 1111,
+					.v_addressable = 1080,
+					.pix_clk_100hz = 1855800,
+				},
+			},
+		},
+		.drr_in_use = true,
+		.use_ramping = false,
+		.drr_window_size_ms = 4,
+		.min_vtotal_supported = 63709,
+		.max_vtotal_supported = 363,
+	},
+	{
+		.desc = "Same Clock Frequency with Prefetch End to Mall Start",
+		.dc = &(struct dc) {
+			.caps = {
+				.subvp_prefetch_end_to_mall_start_us = 500,
+			}
+		},
+		.subvp_pipe = &(struct pipe_ctx) {
+			.stream = &(struct dc_stream_state) {
+				.timing = {
+					.h_total = 2784,
+					.v_addressable = 1080,
+					.pix_clk_100hz = 1855800,
+				},
+				.mall_stream_config = {
+					.paired_stream = &(struct dc_stream_state) {
+						.timing = {
+							.h_total = 3600,
+							.v_total = 1111,
+							.v_addressable = 1080,
+							.v_front_porch = 3,
+							.pix_clk_100hz = 1855800,
+						},
+					},
+				},
+			},
+		},
+		.vblank_pipe = &(struct pipe_ctx) {
+			.stream = &(struct dc_stream_state) {
+				.timing = {
+					.h_total = 2784,
+					.v_total = 1111,
+					.v_addressable = 1080,
+					.pix_clk_100hz = 1855800,
+				},
+			},
+		},
+		.drr_in_use = true,
+		.use_ramping = false,
+		.drr_window_size_ms = 4,
+		.min_vtotal_supported = 63709,
+		.max_vtotal_supported = 346,
+	},
+	{
+		.desc = "Same Clock Frequency Not Multiple of 2",
+		.dc = &(struct dc) {
+			.caps = {
+				.subvp_prefetch_end_to_mall_start_us = 0,
+			}
+		},
+		.subvp_pipe = &(struct pipe_ctx) {
+			.stream = &(struct dc_stream_state) {
+				.timing = {
+					.h_total = 2784,
+					.v_addressable = 1080,
+					.pix_clk_100hz = 1866743,
+				},
+				.mall_stream_config = {
+					.paired_stream = &(struct dc_stream_state) {
+						.timing = {
+							.h_total = 3600,
+							.v_total = 2400,
+							.v_addressable = 2360,
+							.v_front_porch = 4,
+							.pix_clk_100hz = 1866743,
+						},
+					},
+				},
+			},
+		},
+		.vblank_pipe = &(struct pipe_ctx) {
+			.stream = &(struct dc_stream_state) {
+				.timing = {
+					.h_total = 3600,
+					.v_total = 2400,
+					.v_addressable = 2360,
+					.pix_clk_100hz = 1866743,
+				},
+			},
+		},
+		.drr_in_use = true,
+		.use_ramping = false,
+		.drr_window_size_ms = 4,
+		.min_vtotal_supported = 1387,
+		.max_vtotal_supported = 399,
+	},
+	{
+		.desc = "Different Clock Frequency for smaller h_total and v_total",
+		.dc = &(struct dc) {
+			.caps = {
+				.subvp_prefetch_end_to_mall_start_us = 300,
+			}
+		},
+		.subvp_pipe = &(struct pipe_ctx) {
+			.stream = &(struct dc_stream_state) {
+				.timing = {
+					.h_total = 1280,
+					.v_addressable = 600,
+					.pix_clk_100hz = 1855800,
+				},
+				.mall_stream_config = {
+					.paired_stream = &(struct dc_stream_state) {
+						.timing = {
+							.h_total = 1280,
+							.v_total = 720,
+							.v_addressable = 600,
+							.v_front_porch = 4,
+							.pix_clk_100hz = 1866743,
+						},
+					},
+				},
+			},
+		},
+		.vblank_pipe = &(struct pipe_ctx) {
+			.stream = &(struct dc_stream_state) {
+				.timing = {
+					.h_total = 1280,
+					.v_total = 720,
+					.v_addressable = 600,
+					.pix_clk_100hz = 2100800,
+				},
+			},
+		},
+		.drr_in_use = true,
+		.use_ramping = false,
+		.drr_window_size_ms = 4,
+		.min_vtotal_supported = 1477,
+		.max_vtotal_supported = 212,
+	},
+	{
+		.desc = "Different Clock Frequency for approximately 1920x1080",
+		.dc = &(struct dc) {
+			.caps = {
+				.subvp_prefetch_end_to_mall_start_us = 0,
+			}
+		},
+		.subvp_pipe = &(struct pipe_ctx) {
+			.stream = &(struct dc_stream_state) {
+				.timing = {
+					.h_total = 1920,
+					.v_addressable = 1000,
+					.pix_clk_100hz = 1855800,
+				},
+				.mall_stream_config = {
+					.paired_stream = &(struct dc_stream_state) {
+						.timing = {
+							.h_total = 1911,
+							.v_total = 1080,
+							.v_addressable = 1000,
+							.v_front_porch = 7,
+							.pix_clk_100hz = 1866743,
+						},
+					},
+				},
+			},
+		},
+		.vblank_pipe = &(struct pipe_ctx) {
+			.stream = &(struct dc_stream_state) {
+				.timing = {
+					.h_total = 1280,
+					.v_total = 720,
+					.v_addressable = 600,
+					.pix_clk_100hz = 2100800,
+				},
+			},
+		},
+		.drr_in_use = true,
+		.use_ramping = false,
+		.drr_window_size_ms = 4,
+		.min_vtotal_supported = 2482,
+		.max_vtotal_supported = 247,
+	},
+};
+
+static void populate_subvp_cmd_drr_info_test_to_desc(struct
+		populate_subvp_cmd_drr_info_test_case * t, char *desc)
+{
+	strcpy(desc, t->desc);
+}
+
+KUNIT_ARRAY_PARAM(populate_subvp_cmd_drr_info, populate_subvp_cmd_drr_info_cases,
+		  populate_subvp_cmd_drr_info_test_to_desc);
+
+static void populate_subvp_cmd_drr_info_test(struct kunit *test)
+{
+	const struct populate_subvp_cmd_drr_info_test_case *test_param =
+		test->param_value;
+	struct dmub_cmd_fw_assisted_mclk_switch_pipe_data_v2 *pipe_data;
+
+	pipe_data = kunit_kzalloc(test,
+				  sizeof(struct dmub_cmd_fw_assisted_mclk_switch_pipe_data_v2),
+				  GFP_KERNEL);
+
+	populate_subvp_cmd_drr_info(test_param->dc, test_param->subvp_pipe,
+				    test_param->vblank_pipe, pipe_data);
+
+	KUNIT_EXPECT_EQ(test, test_param->drr_in_use,
+			pipe_data->pipe_config.vblank_data.drr_info.drr_in_use);
+	KUNIT_EXPECT_EQ(test, test_param->drr_window_size_ms,
+			pipe_data->pipe_config.vblank_data.drr_info.drr_window_size_ms);
+	KUNIT_EXPECT_EQ(test, test_param->use_ramping,
+			pipe_data->pipe_config.vblank_data.drr_info.use_ramping);
+	KUNIT_EXPECT_EQ(test, test_param->min_vtotal_supported,
+			pipe_data->pipe_config.vblank_data.drr_info.min_vtotal_supported);
+	KUNIT_EXPECT_EQ(test, test_param->max_vtotal_supported,
+			pipe_data->pipe_config.vblank_data.drr_info.max_vtotal_supported);
+}
+
+static struct kunit_case dc_dmub_srv_cases[] = {
+	KUNIT_CASE_PARAM(populate_subvp_cmd_drr_info_test, populate_subvp_cmd_drr_info_gen_params),
+	{  }
+};
+
+static struct kunit_suite dc_dmub_srv_suite = {
+	.name = "dc_dmub_srv",
+	.test_cases = dc_dmub_srv_cases,
+};
+
+kunit_test_suite(dc_dmub_srv_suite);
-- 
2.37.3

Hi Maíra,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on drm/drm-next]
[also build test ERROR on drm-intel/for-linux-next drm-tip/drm-tip linus/master v6.0-rc5 next-20220914]
[cannot apply to drm-misc/drm-misc-next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Ma-ra-Canal/drm-amd-display-Introduce-KUnit-to-Display-Mode-Library/20220913-000256
base:   git://anongit.freedesktop.org/drm/drm drm-next
config: loongarch-randconfig-r026-20220914 (https://download.01.org/0day-ci/archive/20220915/202209150834.M0BeSpLy-lkp@intel.com/config)
compiler: loongarch64-linux-gcc (GCC) 12.1.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/intel-lab-lkp/linux/commit/50e2391775a6552a521c783a6fcd36942b906e3f
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Ma-ra-Canal/drm-amd-display-Introduce-KUnit-to-Display-Mode-Library/20220913-000256
        git checkout 50e2391775a6552a521c783a6fcd36942b906e3f
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross W=1 O=build_dir ARCH=loongarch SHELL=/bin/bash

If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   In file included from drivers/gpu/drm/amd/amdgpu/../display/dc/dc_dmub_srv.c:863:
   drivers/gpu/drm/amd/amdgpu/../display/dc/../tests/dc/dc_dmub_srv_test.c: In function 'populate_subvp_cmd_drr_info_test':
>> drivers/gpu/drm/amd/amdgpu/../display/dc/../tests/dc/dc_dmub_srv_test.c:260:9: error: implicit declaration of function 'populate_subvp_cmd_drr_info'; did you mean 'populate_subvp_cmd_drr_info_test'? [-Werror=implicit-function-declaration]
     260 |         populate_subvp_cmd_drr_info(test_param->dc, test_param->subvp_pipe,
         |         ^~~~~~~~~~~~~~~~~~~~~~~~~~~
         |         populate_subvp_cmd_drr_info_test
   In file included from drivers/gpu/drm/amd/amdgpu/../display/dc/inc/core_types.h:32,
                    from drivers/gpu/drm/amd/amdgpu/../display/dc/dc_dmub_srv.c:31:
   drivers/gpu/drm/amd/amdgpu/../display/include/ddc_service_types.h: At top level:
   drivers/gpu/drm/amd/amdgpu/../display/include/ddc_service_types.h:137:22: warning: 'SYNAPTICS_DEVICE_ID' defined but not used [-Wunused-const-variable=]
     137 | static const uint8_t SYNAPTICS_DEVICE_ID[] = "SYNA";
         |                      ^~~~~~~~~~~~~~~~~~~
   drivers/gpu/drm/amd/amdgpu/../display/include/ddc_service_types.h:134:17: warning: 'DP_SINK_BRANCH_DEV_NAME_7580' defined but not used [-Wunused-const-variable=]
     134 | static const u8 DP_SINK_BRANCH_DEV_NAME_7580[] = "7580\x80u";
         |                 ^~~~~~~~~~~~~~~~~~~~~~~~~~~~
   drivers/gpu/drm/amd/amdgpu/../display/include/ddc_service_types.h:132:22: warning: 'DP_SINK_DEVICE_STR_ID_2' defined but not used [-Wunused-const-variable=]
     132 | static const uint8_t DP_SINK_DEVICE_STR_ID_2[] = {7, 1, 8, 7, 5, 0};
         |                      ^~~~~~~~~~~~~~~~~~~~~~~
   drivers/gpu/drm/amd/amdgpu/../display/include/ddc_service_types.h:131:22: warning: 'DP_SINK_DEVICE_STR_ID_1' defined but not used [-Wunused-const-variable=]
     131 | static const uint8_t DP_SINK_DEVICE_STR_ID_1[] = {7, 1, 8, 7, 3, 0};
         |                      ^~~~~~~~~~~~~~~~~~~~~~~
   cc1: some warnings being treated as errors


vim +260 drivers/gpu/drm/amd/amdgpu/../display/dc/../tests/dc/dc_dmub_srv_test.c

   246	
   247	KUNIT_ARRAY_PARAM(populate_subvp_cmd_drr_info, populate_subvp_cmd_drr_info_cases,
   248			  populate_subvp_cmd_drr_info_test_to_desc);
   249	
   250	static void populate_subvp_cmd_drr_info_test(struct kunit *test)
   251	{
   252		const struct populate_subvp_cmd_drr_info_test_case *test_param =
   253			test->param_value;
   254		struct dmub_cmd_fw_assisted_mclk_switch_pipe_data_v2 *pipe_data;
   255	
   256		pipe_data = kunit_kzalloc(test,
   257					  sizeof(struct dmub_cmd_fw_assisted_mclk_switch_pipe_data_v2),
   258					  GFP_KERNEL);
   259	
 > 260		populate_subvp_cmd_drr_info(test_param->dc, test_param->subvp_pipe,
   261					    test_param->vblank_pipe, pipe_data);
   262	
   263		KUNIT_EXPECT_EQ(test, test_param->drr_in_use,
   264				pipe_data->pipe_config.vblank_data.drr_info.drr_in_use);
   265		KUNIT_EXPECT_EQ(test, test_param->drr_window_size_ms,
   266				pipe_data->pipe_config.vblank_data.drr_info.drr_window_size_ms);
   267		KUNIT_EXPECT_EQ(test, test_param->use_ramping,
   268				pipe_data->pipe_config.vblank_data.drr_info.use_ramping);
   269		KUNIT_EXPECT_EQ(test, test_param->min_vtotal_supported,
   270				pipe_data->pipe_config.vblank_data.drr_info.min_vtotal_supported);
   271		KUNIT_EXPECT_EQ(test, test_param->max_vtotal_supported,
   272				pipe_data->pipe_config.vblank_data.drr_info.max_vtotal_supported);
   273	}
   274	

-- 
0-DAY CI Kernel Test Service
https://01.org/lkp