[PATCH 106/108] drm/i915/kunit: DP link: add baseline fixed table reference test

[Imre Deak <imre.deak@intel.com>]

Add a simple baseline test for DP link caps iteration using a fixed
standard DP configuration table. This provides a minimal validity check,
independent of more complex test setups, verifying the iterator returns
expected configurations in ascending and descending order.

Signed-off-by: Imre Deak <imre.deak@intel.com>
---
 .../i915/display/tests/intel_dp_link_test.c   | 238 ++++++++++++++++++
 1 file changed, 238 insertions(+)

diff --git a/drivers/gpu/drm/i915/display/tests/intel_dp_link_test.c b/drivers/gpu/drm/i915/display/tests/intel_dp_link_test.c
index 15179b4d08d1a..e6feb68cb912f 100644
--- a/drivers/gpu/drm/i915/display/tests/intel_dp_link_test.c
+++ b/drivers/gpu/drm/i915/display/tests/intel_dp_link_test.c
@@ -7,6 +7,7 @@
 
 #include <linux/compiler.h>
 #include <linux/device.h>
+#include <linux/log2.h>
 #include <linux/prandom.h>
 #include <linux/random.h>
 
@@ -20,6 +21,34 @@
 #include "intel_dp_link_caps.h"
 #include "intel_dp_link_training.h"
 
+#define test_for_each_dp_link_config_idx(__test_ctx, __config_order, __config_mask, \
+					 __config, __config_idx) \
+	for_each_dp_link_config_idx_iter((__test_ctx)->dev.dp.link.caps, \
+					 (__test_ctx)->link_caps_ops->get_config_by_pos, \
+					 (__config_order), (__config_mask), (__config), (__config_idx))
+
+#define test_for_each_dp_link_config(__test_ctx, __config_order, __config_mask, __config) \
+	test_for_each_dp_link_config_idx((__test_ctx), (__config_order), (__config_mask), \
+					 (__config), NULL)
+
+#define LINK_TEST_NUM_LANE_CONFIGS(__max_lane_count) \
+	(ilog2(__max_lane_count) + 1)
+
+#define LINK_TEST_NUM_CONFIGS(__num_rates, __max_lane_count) \
+	((__num_rates) * LINK_TEST_NUM_LANE_CONFIGS(__max_lane_count))
+
+#define LINK_TEST_MAX_LANE_COUNT		((u32)4)
+#define LINK_TEST_MAX_CONFIGS			LINK_TEST_NUM_CONFIGS(DP_MAX_SUPPORTED_RATES, \
+								      LINK_TEST_MAX_LANE_COUNT)
+
+#define LINK_TEST_NUM_RANDOM_ITERATIONS		50
+
+enum test_config_order_key {
+	TEST_CONFIG_ORDER_KEY_BW,
+	TEST_CONFIG_ORDER_KEY_RATE_LANE,
+	TEST_CONFIG_ORDER_KEY_LANE_RATE,
+};
+
 struct test_ctx {
 	struct {
 		struct intel_display display;
@@ -38,7 +67,216 @@ struct test_ctx {
 	struct rnd_state rnd;
 };
 
+struct test_config_order {
+	enum test_config_order_key key;
+	enum intel_dp_link_caps_config_order_direction dir;
+};
+
+struct link_rate_set {
+	const int *entries;
+	int size;
+};
+
+struct link_config_set {
+	struct intel_dp_link_config entries[LINK_TEST_MAX_CONFIGS];
+	int size;
+};
+
+static const int standard_dp_link_rates[] = {
+	162000, 270000, 540000, 810000, 1000000, 1350000, 2000000
+};
+
+#define LINK_TEST_NUM_STANDARD_RATES (ARRAY_SIZE(standard_dp_link_rates))
+
+static const struct link_config_set standard_dp_link_configs[] = {
+	[TEST_CONFIG_ORDER_KEY_BW] = {                        /* MBps    PBN    */
+		.entries = {
+			{ .rate =  162000, .lane_count = 1 }, /*  162.0    3.00 */
+			{ .rate =  270000, .lane_count = 1 }, /*  270.0    5.00 */
+			{ .rate =  162000, .lane_count = 2 }, /*  324.0    6.00 */
+			{ .rate =  270000, .lane_count = 2 }, /*  540.0   10.00 */
+			{ .rate =  540000, .lane_count = 1 }, /*  540.0   10.00 */
+			{ .rate =  162000, .lane_count = 4 }, /*  648.0   12.00 */
+			{ .rate =  810000, .lane_count = 1 }, /*  810.0   15.00 */
+			{ .rate =  270000, .lane_count = 4 }, /* 1080.0   20.00 */
+			{ .rate =  540000, .lane_count = 2 }, /* 1080.0   20.00 */
+			{ .rate = 1000000, .lane_count = 1 }, /* 1208.9   22.39 */
+			{ .rate =  810000, .lane_count = 2 }, /* 1620.0   30.00 */
+			{ .rate = 1350000, .lane_count = 1 }, /* 1632.0   30.22 */
+			{ .rate =  540000, .lane_count = 4 }, /* 2160.0   40.00 */
+			{ .rate = 1000000, .lane_count = 2 }, /* 2417.8   44.77 */
+			{ .rate = 2000000, .lane_count = 1 }, /* 2417.8   44.77 */
+			{ .rate =  810000, .lane_count = 4 }, /* 3240.0   60.00 */
+			{ .rate = 1350000, .lane_count = 2 }, /* 3264.0   60.44 */
+			{ .rate = 1000000, .lane_count = 4 }, /* 4835.6   89.55 */
+			{ .rate = 2000000, .lane_count = 2 }, /* 4835.6   89.55 */
+			{ .rate = 1350000, .lane_count = 4 }, /* 6527.9  120.89 */
+			{ .rate = 2000000, .lane_count = 4 }, /* 9671.1  179.09 */
+		},
+		.size = LINK_TEST_NUM_CONFIGS(ARRAY_SIZE(standard_dp_link_rates),
+					      LINK_TEST_MAX_LANE_COUNT),
+	},
+	[TEST_CONFIG_ORDER_KEY_RATE_LANE] = {
+		.entries = {
+			{ .rate = 162000,  .lane_count = 1 },
+			{ .rate = 162000,  .lane_count = 2 },
+			{ .rate = 162000,  .lane_count = 4 },
+
+			{ .rate = 270000,  .lane_count = 1 },
+			{ .rate = 270000,  .lane_count = 2 },
+			{ .rate = 270000,  .lane_count = 4 },
+
+			{ .rate = 540000,  .lane_count = 1 },
+			{ .rate = 540000,  .lane_count = 2 },
+			{ .rate = 540000,  .lane_count = 4 },
+
+			{ .rate = 810000,  .lane_count = 1 },
+			{ .rate = 810000,  .lane_count = 2 },
+			{ .rate = 810000,  .lane_count = 4 },
+
+			{ .rate = 1000000, .lane_count = 1 },
+			{ .rate = 1000000, .lane_count = 2 },
+			{ .rate = 1000000, .lane_count = 4 },
+
+			{ .rate = 1350000, .lane_count = 1 },
+			{ .rate = 1350000, .lane_count = 2 },
+			{ .rate = 1350000, .lane_count = 4 },
+
+			{ .rate = 2000000, .lane_count = 1 },
+			{ .rate = 2000000, .lane_count = 2 },
+			{ .rate = 2000000, .lane_count = 4 },
+		},
+		.size = LINK_TEST_NUM_CONFIGS(ARRAY_SIZE(standard_dp_link_rates),
+					      LINK_TEST_MAX_LANE_COUNT),
+	},
+	[TEST_CONFIG_ORDER_KEY_LANE_RATE] = {
+		.entries = {
+			{ .rate = 162000,  .lane_count = 1 },
+			{ .rate = 270000,  .lane_count = 1 },
+			{ .rate = 540000,  .lane_count = 1 },
+			{ .rate = 810000,  .lane_count = 1 },
+			{ .rate = 1000000, .lane_count = 1 },
+			{ .rate = 1350000, .lane_count = 1 },
+			{ .rate = 2000000, .lane_count = 1 },
+
+			{ .rate = 162000,  .lane_count = 2 },
+			{ .rate = 270000,  .lane_count = 2 },
+			{ .rate = 540000,  .lane_count = 2 },
+			{ .rate = 810000,  .lane_count = 2 },
+			{ .rate = 1000000, .lane_count = 2 },
+			{ .rate = 1350000, .lane_count = 2 },
+			{ .rate = 2000000, .lane_count = 2 },
+
+			{ .rate = 162000,  .lane_count = 4 },
+			{ .rate = 270000,  .lane_count = 4 },
+			{ .rate = 540000,  .lane_count = 4 },
+			{ .rate = 810000,  .lane_count = 4 },
+			{ .rate = 1000000, .lane_count = 4 },
+			{ .rate = 1350000, .lane_count = 4 },
+			{ .rate = 2000000, .lane_count = 4 },
+		},
+		.size = LINK_TEST_NUM_CONFIGS(ARRAY_SIZE(standard_dp_link_rates),
+					      LINK_TEST_MAX_LANE_COUNT),
+	},
+};
+
+static bool link_configs_match(const struct intel_dp_link_config *a,
+			       const struct intel_dp_link_config *b)
+{
+	return a->rate == b->rate && a->lane_count == b->lane_count;
+}
+
+static u32 get_all_config_mask(void)
+{
+	return GENMASK_U32(LINK_TEST_MAX_CONFIGS - 1, 0);
+}
+
+static const struct intel_dp_link_caps_config_order config_orders[] = {
+	{
+		.key = INTEL_DP_LINK_CAPS_CONFIG_ORDER_KEY_BW,
+		.dir = INTEL_DP_LINK_CAPS_CONFIG_ORDER_DIR_ASC,
+	}, {
+		.key = INTEL_DP_LINK_CAPS_CONFIG_ORDER_KEY_BW,
+		.dir = INTEL_DP_LINK_CAPS_CONFIG_ORDER_DIR_DESC,
+	}, {
+		.key = INTEL_DP_LINK_CAPS_CONFIG_ORDER_KEY_RATE_LANE,
+		.dir = INTEL_DP_LINK_CAPS_CONFIG_ORDER_DIR_ASC,
+	}, {
+		.key = INTEL_DP_LINK_CAPS_CONFIG_ORDER_KEY_RATE_LANE,
+		.dir = INTEL_DP_LINK_CAPS_CONFIG_ORDER_DIR_DESC,
+	}
+};
+
+static enum test_config_order_key
+link_caps_to_test_config_order_key(struct kunit *test, enum intel_dp_link_caps_config_order_key key)
+{
+	switch (key) {
+	case INTEL_DP_LINK_CAPS_CONFIG_ORDER_KEY_BW:
+		return TEST_CONFIG_ORDER_KEY_BW;
+	case INTEL_DP_LINK_CAPS_CONFIG_ORDER_KEY_RATE_LANE:
+		return TEST_CONFIG_ORDER_KEY_RATE_LANE;
+	default:
+		KUNIT_FAIL_AND_ABORT(test, "Missing link caps order key: %d\n", key);
+	}
+}
+
+static const struct link_config_set *
+link_caps_config_order_key_to_set(struct kunit *test, enum intel_dp_link_caps_config_order_key key)
+{
+	enum test_config_order_key test_order_key =
+		link_caps_to_test_config_order_key(test, key);
+
+	return &standard_dp_link_configs[test_order_key];
+}
+
+/*
+ * TEST: Baseline with fixed reference table
+ * -----------------------------------------
+ * Verify the link_caps config iterator using fixed standard DP config tables.
+ */
+static void baseline_test_for_order(struct kunit *test,
+				    struct intel_dp_link_caps *link_caps,
+				    struct intel_dp_link_caps_config_order config_order)
+{
+	struct test_ctx *ctx = test->priv;
+	const struct link_config_set *config_set =
+		link_caps_config_order_key_to_set(test, config_order.key);
+	struct intel_dp_link_config iter_config;
+	int pos = 0;
+
+	test_for_each_dp_link_config(ctx, config_order, get_all_config_mask(), &iter_config) {
+		int idx = pos;
+
+		if (config_order.dir == INTEL_DP_LINK_CAPS_CONFIG_ORDER_DIR_DESC)
+			idx = config_set->size - idx - 1;
+
+		KUNIT_EXPECT_TRUE(test, link_configs_match(&iter_config,
+							   &config_set->entries[idx]));
+
+		pos++;
+	}
+}
+
+static void intel_dp_link_caps_test_baseline(struct kunit *test)
+{
+	struct test_ctx *ctx = test->priv;
+	struct intel_dp_link_caps *link_caps = ctx->dev.dp.link.caps;
+	const struct intel_dp_link_caps_test_ops *ops =
+		ctx->link_caps_ops;
+	int i;
+
+	ops->update(link_caps,
+		    standard_dp_link_rates, LINK_TEST_NUM_STANDARD_RATES,
+		    LINK_TEST_MAX_LANE_COUNT,
+		    INTEL_DP_LINK_CAPS_UPDATE_RESET);
+
+	for (i = 0; i < ARRAY_SIZE(config_orders); i++)
+		baseline_test_for_order(test, link_caps, config_orders[i]);
+}
+
 static struct kunit_case intel_dp_link_test_cases[] = {
+	KUNIT_CASE(intel_dp_link_caps_test_baseline),
+
 	{}
 };
 
-- 
2.49.1