drm/xe/tests: Add object encoding helper test

We will soon be encoding complex objects as KLVs using our helper
function. Add few simple tests to make sure this helper function
works as expected.

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Michał Winiarski <michal.winiarski@intel.com>
Link: https://patch.msgid.link/20260710195945.7316-1-michal.wajdeczko@intel.com

1 files changed, 205 insertions, 0 deletions

diff --git a/drivers/gpu/drm/xe/tests/xe_guc_klv_helpers_kunit.c b/drivers/gpu/drm/xe/tests/xe_guc_klv_helpers_kunit.c
index cb4b182d88d0..33d7a52f6bf8 100644
--- a/drivers/gpu/drm/xe/tests/xe_guc_klv_helpers_kunit.c
+++ b/drivers/gpu/drm/xe/tests/xe_guc_klv_helpers_kunit.c
@@ -7,6 +7,7 @@
 #include <kunit/test-bug.h>
 
 #define TEST_KEY	(GUC_KLV_RESERVED_RANGE_START + 0x3de)
+#define TEST_GROUP_KEY	(GUC_KLV_RESERVED_RANGE_START + 0x3f0)
 #define TEST_PAD	0xdeadbeef
 
 static void test_count(struct kunit *test)
@@ -167,11 +168,215 @@ static void test_encode_string(struct kunit *test)
 			    xe_guc_klv_encode_string(klvs, avail, key, buf));
 }
 
+struct some_object {
+	u32 value1;
+	u64 value2;
+} __packed;
+
+static u32 *obj_raw_encoder(u32 *klvs, u32 avail, const void *arg)
+{
+	const struct some_object *obj = arg;
+	size_t sz = sizeof(*obj);
+	u32 dwords = to_num_dwords(sz);
+
+	if (IS_ERR(klvs))
+		return klvs;
+	if (dwords > avail)
+		return ERR_PTR(-ENOSPC);
+	memcpy(klvs, obj, sz);
+	return klvs + dwords;
+}
+
+static u32 *obj_klv_encoder(u32 *klvs, u32 avail, const void *arg)
+{
+	const struct some_object *obj = arg;
+	u32 *end = klvs + avail;
+
+	klvs = xe_guc_klv_encode_u32(klvs, end - klvs, TEST_KEY + 1, obj->value1);
+	klvs = xe_guc_klv_encode_u64(klvs, end - klvs, TEST_KEY + 2, obj->value2);
+	return klvs;
+}
+
+static u32 *obj_nested_encoder(u32 *klvs, u32 avail, const void *arg)
+{
+	u32 *end = klvs + avail;
+
+	klvs = xe_guc_klv_encode_object(klvs, end - klvs, TEST_GROUP_KEY + 1,
+					arg, obj_klv_encoder);
+	klvs = xe_guc_klv_encode_object(klvs, end - klvs, TEST_GROUP_KEY + 2,
+					arg, obj_klv_encoder);
+	return klvs;
+}
+
+static void test_encode_object_raw(struct kunit *test)
+{
+	const struct some_object obj = {
+		.value1 = 0xdead1234,
+		.value2 = 0xdead87654321dead,
+	};
+	u32 payload = to_num_dwords(sizeof(obj));
+	u32 *err = ERR_PTR(-ENOSPC);
+	u16 key = TEST_KEY;
+	u32 klvs[16];
+	u32 n;
+
+	/* too small, must fail */
+	for (n = 0; n < GUC_KLV_LEN_MIN + payload; n++) {
+		memset32(klvs, TEST_PAD, ARRAY_SIZE(klvs));
+		KUNIT_EXPECT_PTR_EQ_MSG(test, ERR_PTR(-ENOSPC),
+					xe_guc_klv_encode_object(klvs, n, key, &obj,
+								 obj_raw_encoder),
+					"buf size=%u dwords", n);
+	}
+
+	/* must pass */
+	memset32(klvs, TEST_PAD, ARRAY_SIZE(klvs));
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test,
+				     xe_guc_klv_encode_object(klvs, GUC_KLV_LEN_MIN + payload,
+							      key, &obj, obj_raw_encoder));
+	KUNIT_EXPECT_EQ(test, klvs[0], PREP_GUC_KLV(key, payload));
+	KUNIT_EXPECT_MEMEQ(test, &klvs[1], &obj, sizeof(obj));
+
+	/* already failed, must fail */
+	KUNIT_ASSERT_PTR_EQ(test, err,
+			    xe_guc_klv_encode_object(err, ARRAY_SIZE(klvs), key,
+						     &obj, obj_raw_encoder));
+}
+
+static void test_encode_object_klv(struct kunit *test)
+{
+	const struct some_object obj = {
+		.value1 = 0xdead1234,
+		.value2 = 0xdead87654321dead,
+	};
+	u16 key = TEST_GROUP_KEY;
+	u32 payload = 0;
+	u32 klvs[16];
+	u32 n;
+
+	payload += GUC_KLV_LEN_MIN + to_num_dwords(sizeof(obj.value1));
+	payload += GUC_KLV_LEN_MIN + to_num_dwords(sizeof(obj.value2));
+
+	/* too small, must fail */
+	for (n = 0; n < GUC_KLV_LEN_MIN + payload; n++) {
+		memset32(klvs, TEST_PAD, ARRAY_SIZE(klvs));
+		KUNIT_EXPECT_PTR_EQ_MSG(test, ERR_PTR(-ENOSPC),
+					xe_guc_klv_encode_object(klvs, n, key, &obj,
+								 obj_klv_encoder),
+					"buf size=%u dwords", n);
+	}
+
+	/* must pass */
+	memset32(klvs, TEST_PAD, ARRAY_SIZE(klvs));
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test,
+				     xe_guc_klv_encode_object(klvs, GUC_KLV_LEN_MIN + payload,
+							      key, &obj, obj_klv_encoder));
+	KUNIT_EXPECT_EQ(test, klvs[0], PREP_GUC_KLV(key, payload));
+	KUNIT_EXPECT_EQ(test, klvs[1], PREP_GUC_KLV(TEST_KEY + 1, 1));
+	KUNIT_EXPECT_EQ(test, klvs[2], obj.value1);
+	KUNIT_EXPECT_EQ(test, klvs[3], PREP_GUC_KLV(TEST_KEY + 2, 2));
+	KUNIT_EXPECT_EQ(test, klvs[4], lower_32_bits(obj.value2));
+	KUNIT_EXPECT_EQ(test, klvs[5], upper_32_bits(obj.value2));
+	KUNIT_EXPECT_EQ(test, klvs[6], TEST_PAD);
+}
+
+static void test_encode_object_nested(struct kunit *test)
+{
+	const struct some_object obj = {
+		.value1 = 0xdead1234,
+		.value2 = 0xdead87654321dead,
+	};
+	u16 key = TEST_GROUP_KEY;
+	u32 payload = 0;
+	u32 klvs[16];
+	u32 n;
+
+	payload += GUC_KLV_LEN_MIN;
+	payload += GUC_KLV_LEN_MIN + to_num_dwords(sizeof(obj.value1));
+	payload += GUC_KLV_LEN_MIN + to_num_dwords(sizeof(obj.value2));
+	payload *= 2;
+
+	/* too small, must fail */
+	for (n = 0; n < GUC_KLV_LEN_MIN + payload; n++) {
+		memset32(klvs, TEST_PAD, ARRAY_SIZE(klvs));
+		KUNIT_EXPECT_PTR_EQ_MSG(test, ERR_PTR(-ENOSPC),
+					xe_guc_klv_encode_object(klvs, n, key, &obj,
+								 obj_nested_encoder),
+					"buf size=%u dwords", n);
+	}
+
+	/* must pass */
+	memset32(klvs, TEST_PAD, ARRAY_SIZE(klvs));
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test,
+				     xe_guc_klv_encode_object(klvs, GUC_KLV_LEN_MIN + payload,
+							      key, &obj, obj_nested_encoder));
+	KUNIT_EXPECT_EQ(test, klvs[0], PREP_GUC_KLV(key, payload));
+	KUNIT_EXPECT_EQ(test, klvs[1], PREP_GUC_KLV(TEST_GROUP_KEY + 1, 5));
+	KUNIT_EXPECT_EQ(test, klvs[2], PREP_GUC_KLV(TEST_KEY + 1, 1));
+	KUNIT_EXPECT_EQ(test, klvs[3], obj.value1);
+	KUNIT_EXPECT_EQ(test, klvs[4], PREP_GUC_KLV(TEST_KEY + 2, 2));
+	KUNIT_EXPECT_EQ(test, klvs[5], lower_32_bits(obj.value2));
+	KUNIT_EXPECT_EQ(test, klvs[6], upper_32_bits(obj.value2));
+	KUNIT_EXPECT_EQ(test, klvs[7], PREP_GUC_KLV(TEST_GROUP_KEY + 2, 5));
+	KUNIT_EXPECT_EQ(test, klvs[8], PREP_GUC_KLV(TEST_KEY + 1, 1));
+	KUNIT_EXPECT_EQ(test, klvs[9], obj.value1);
+	KUNIT_EXPECT_EQ(test, klvs[10], PREP_GUC_KLV(TEST_KEY + 2, 2));
+	KUNIT_EXPECT_EQ(test, klvs[11], lower_32_bits(obj.value2));
+	KUNIT_EXPECT_EQ(test, klvs[12], upper_32_bits(obj.value2));
+	KUNIT_EXPECT_EQ(test, klvs[13], TEST_PAD);
+}
+
+static u32 *obj_echo_encoder(u32 *klvs, u32 avail, const void *arg)
+{
+	return ERR_CAST(arg);
+}
+
+static void test_encode_object_basic(struct kunit *test)
+{
+	u32 longest = GUC_KLV_LEN_MIN + FIELD_MAX(GUC_KLV_0_LEN);
+	u32 avail = GUC_KLV_LEN_MIN + longest;
+	u16 key = TEST_GROUP_KEY;
+	u32 *klvs;
+
+	klvs = kunit_kcalloc(test, avail, sizeof(u32), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, klvs);
+
+	/* smallest */
+	KUNIT_EXPECT_PTR_EQ(test, klvs + GUC_KLV_LEN_MIN,
+			    xe_guc_klv_encode_object(klvs, avail, key,
+						     klvs + GUC_KLV_LEN_MIN,
+						     obj_echo_encoder));
+	/* largest */
+	KUNIT_EXPECT_PTR_EQ(test, klvs + longest,
+			    xe_guc_klv_encode_object(klvs, avail, key,
+						     klvs + longest,
+						     obj_echo_encoder));
+	/* already failed */
+	KUNIT_EXPECT_PTR_EQ(test, ERR_PTR(-EROFS),
+			    xe_guc_klv_encode_object(ERR_PTR(-EROFS), avail, key,
+						     klvs + GUC_KLV_LEN_MIN,
+						     obj_echo_encoder));
+	/* encoding error */
+	KUNIT_EXPECT_PTR_EQ(test, ERR_PTR(-EUCLEAN),
+			    xe_guc_klv_encode_object(klvs, avail, key,
+						     ERR_PTR(-EUCLEAN),
+						     obj_echo_encoder));
+	/* no space */
+	KUNIT_EXPECT_PTR_EQ(test, ERR_PTR(-ENOSPC),
+			    xe_guc_klv_encode_object(klvs, 0, key,
+						     klvs + GUC_KLV_LEN_MIN,
+						     obj_echo_encoder));
+}
+
 static struct kunit_case guc_klv_helpers_test_cases[] = {
 	KUNIT_CASE(test_count),
 	KUNIT_CASE(test_encode_u32),
 	KUNIT_CASE(test_encode_u64),
 	KUNIT_CASE(test_encode_string),
+	KUNIT_CASE(test_encode_object_raw),
+	KUNIT_CASE(test_encode_object_klv),
+	KUNIT_CASE(test_encode_object_nested),
+	KUNIT_CASE(test_encode_object_basic),
 	{}
 };