Add kunit test cases for drm_dp_get_vc_payload_bw() with all the DP1.4
and UHBR link configurations.
v2:
- List test cases in decreasing rate,lane count order matching the
corresponding DP Standard tables. (Ville)
- Add references to the DP Standard tables.
v3:
- Sort the testcases properly.
v4:
- Avoid 'stack frame size x exceeds limit y in
drm_test_dp_mst_calc_pbn_div()' compiler warn. (LKP)
Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx>
Cc: Lyude Paul <lyude@xxxxxxxxxx>
Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
Cc: kernel test robot <lkp@xxxxxxxxx>
Reviewed-by: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> (v3)
Signed-off-by: Imre Deak <imre.deak@xxxxxxxxx>
---
.../gpu/drm/tests/drm_dp_mst_helper_test.c | 160 ++++++++++++++++++
1 file changed, 160 insertions(+)
diff --git a/drivers/gpu/drm/tests/drm_dp_mst_helper_test.c b/drivers/gpu/drm/tests/drm_dp_mst_helper_test.c
index e3c818dfc0e6d..d916e548fcb12 100644
--- a/drivers/gpu/drm/tests/drm_dp_mst_helper_test.c
+++ b/drivers/gpu/drm/tests/drm_dp_mst_helper_test.c
@@ -68,6 +68,152 @@ static void dp_mst_calc_pbn_mode_desc(const struct drm_dp_mst_calc_pbn_mode_test
KUNIT_ARRAY_PARAM(drm_dp_mst_calc_pbn_mode, drm_dp_mst_calc_pbn_mode_cases,
dp_mst_calc_pbn_mode_desc);
+struct drm_dp_mst_calc_pbn_div_test {
+ int link_rate;
+ int lane_count;
+ fixed20_12 expected;
+};
+
+#define fp_init(__int, __frac) { \
+ .full = (__int) * (1 << 12) + \
+ (__frac) * (1 << 12) / 100000 \
+}
+
+static const struct drm_dp_mst_calc_pbn_div_test drm_dp_mst_calc_pbn_div_dp1_4_cases[] = {
+ /*
+ * UHBR rates (DP Standard v2.1 2.7.6.3, specifying the rounded to
+ * closest value to 2 decimal places):
+ * .expected = .link_rate * .lane_count * 0.9671 / 8 / 54 / 100
+ * DP1.4 rates (DP Standard v2.1 2.6.4.2):
+ * .expected = .link_rate * .lane_count * 0.8000 / 8 / 54 / 100
+ *
+ * truncated to 5 decimal places.
+ */
+ {
+ .link_rate = 2000000,
+ .lane_count = 4,
+ .expected = fp_init(179, 9259), /* 179.09259 */
+ },
+ {
+ .link_rate = 2000000,
+ .lane_count = 2,
+ .expected = fp_init(89, 54629),
+ },
+ {
+ .link_rate = 2000000,
+ .lane_count = 1,
+ .expected = fp_init(44, 77314),
+ },
+ {
+ .link_rate = 1350000,
+ .lane_count = 4,
+ .expected = fp_init(120, 88750),
+ },
+ {
+ .link_rate = 1350000,
+ .lane_count = 2,
+ .expected = fp_init(60, 44375),
+ },
+ {
+ .link_rate = 1350000,
+ .lane_count = 1,
+ .expected = fp_init(30, 22187),
+ },
+ {
+ .link_rate = 1000000,
+ .lane_count = 4,
+ .expected = fp_init(89, 54629),
+ },
+ {
+ .link_rate = 1000000,
+ .lane_count = 2,
+ .expected = fp_init(44, 77314),
+ },
+ {
+ .link_rate = 1000000,
+ .lane_count = 1,
+ .expected = fp_init(22, 38657),
+ },
+ {
+ .link_rate = 810000,
+ .lane_count = 4,
+ .expected = fp_init(60, 0),
+ },
+ {
+ .link_rate = 810000,
+ .lane_count = 2,
+ .expected = fp_init(30, 0),
+ },
+ {
+ .link_rate = 810000,
+ .lane_count = 1,
+ .expected = fp_init(15, 0),
+ },
+ {
+ .link_rate = 540000,
+ .lane_count = 4,
+ .expected = fp_init(40, 0),
+ },
+ {
+ .link_rate = 540000,
+ .lane_count = 2,
+ .expected = fp_init(20, 0),
+ },
+ {
+ .link_rate = 540000,
+ .lane_count = 1,
+ .expected = fp_init(10, 0),
+ },
+ {
+ .link_rate = 270000,
+ .lane_count = 4,
+ .expected = fp_init(20, 0),
+ },
+ {
+ .link_rate = 270000,
+ .lane_count = 2,
+ .expected = fp_init(10, 0),
+ },
+ {
+ .link_rate = 270000,
+ .lane_count = 1,
+ .expected = fp_init(5, 0),
+ },
+ {
+ .link_rate = 162000,
+ .lane_count = 4,
+ .expected = fp_init(12, 0),
+ },
+ {
+ .link_rate = 162000,
+ .lane_count = 2,
+ .expected = fp_init(6, 0),
+ },
+ {
+ .link_rate = 162000,
+ .lane_count = 1,
+ .expected = fp_init(3, 0),
+ },
+};
+
+static void drm_test_dp_mst_calc_pbn_div(struct kunit *test)
+{
+ const struct drm_dp_mst_calc_pbn_div_test *params = test->param_value;
+ /* mgr->dev is only needed by drm_dbg_kms(), but it's not called for the test cases. */
+ struct drm_dp_mst_topology_mgr *mgr = test->priv;
+
+ KUNIT_EXPECT_EQ(test, drm_dp_get_vc_payload_bw(mgr, params->link_rate, params->lane_count).full,
+ params->expected.full);
+}
+
+static void dp_mst_calc_pbn_div_desc(const struct drm_dp_mst_calc_pbn_div_test *t, char *desc)
+{
+ sprintf(desc, "Link rate %d lane count %d", t->link_rate, t->lane_count);
+}
+
+KUNIT_ARRAY_PARAM(drm_dp_mst_calc_pbn_div, drm_dp_mst_calc_pbn_div_dp1_4_cases,
+ dp_mst_calc_pbn_div_desc);
+
static u8 data[] = { 0xff, 0x00, 0xdd };
struct drm_dp_mst_sideband_msg_req_test {
@@ -416,13 +562,27 @@ KUNIT_ARRAY_PARAM(drm_dp_mst_sideband_msg_req, drm_dp_mst_sideband_msg_req_cases
static struct kunit_case drm_dp_mst_helper_tests[] = {
KUNIT_CASE_PARAM(drm_test_dp_mst_calc_pbn_mode, drm_dp_mst_calc_pbn_mode_gen_params),
+ KUNIT_CASE_PARAM(drm_test_dp_mst_calc_pbn_div, drm_dp_mst_calc_pbn_div_gen_params),
KUNIT_CASE_PARAM(drm_test_dp_mst_sideband_msg_req_decode,
drm_dp_mst_sideband_msg_req_gen_params),
{ }
};
+static int drm_dp_mst_helper_tests_init(struct kunit *test)
+{
+ struct drm_dp_mst_topology_mgr *mgr;
+
+ mgr = kunit_kzalloc(test, sizeof(*mgr), GFP_KERNEL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, mgr);
+
+ test->priv = mgr;
+
+ return 0;
+}
+
static struct kunit_suite drm_dp_mst_helper_test_suite = {
.name = "drm_dp_mst_helper",
+ .init = drm_dp_mst_helper_tests_init,
.test_cases = drm_dp_mst_helper_tests,
};
--
2.39.2
