--- /dev/null
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * KUnit tests for the Interconnect framework.
+ *
+ * Copyright (c) 2025 Kuan-Wei Chiu <visitorckw@gmail.com>
+ *
+ * This suite verifies the behavior of the interconnect core, including
+ * topology construction, bandwidth aggregation, and path lifecycle.
+ */
+
+#include <kunit/platform_device.h>
+#include <kunit/test.h>
+#include <linux/interconnect-provider.h>
+#include <linux/interconnect.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/overflow.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+
+#include "internal.h"
+
+enum {
+ NODE_CPU,
+ NODE_GPU,
+ NODE_BUS,
+ NODE_DDR,
+ NODE_MAX
+};
+
+struct test_node_data {
+ int id;
+ const char *name;
+ int num_links;
+ int links[2];
+};
+
+/*
+ * Static Topology:
+ * CPU -\
+ * -> BUS -> DDR
+ * GPU -/
+ */
+static const struct test_node_data test_topology[] = {
+ { NODE_CPU, "cpu", 1, { NODE_BUS } },
+ { NODE_GPU, "gpu", 1, { NODE_BUS } },
+ { NODE_BUS, "bus", 1, { NODE_DDR } },
+ { NODE_DDR, "ddr", 0, { } },
+};
+
+struct icc_test_priv {
+ struct icc_provider provider;
+ struct platform_device *pdev;
+ struct icc_node *nodes[NODE_MAX];
+};
+
+static struct icc_node *get_node(struct icc_test_priv *priv, int id)
+{
+ int idx = id - NODE_CPU;
+
+ if (idx < 0 || idx >= ARRAY_SIZE(test_topology))
+ return NULL;
+ return priv->nodes[idx];
+}
+
+static int icc_test_set(struct icc_node *src, struct icc_node *dst)
+{
+ return 0;
+}
+
+static int icc_test_aggregate(struct icc_node *node, u32 tag, u32 avg_bw,
+ u32 peak_bw, u32 *agg_avg, u32 *agg_peak)
+{
+ return icc_std_aggregate(node, tag, avg_bw, peak_bw, agg_avg, agg_peak);
+}
+
+static struct icc_node *icc_test_xlate(const struct of_phandle_args *spec, void *data)
+{
+ return NULL;
+}
+
+static int icc_test_get_bw(struct icc_node *node, u32 *avg, u32 *peak)
+{
+ *avg = 0;
+ *peak = 0;
+
+ return 0;
+}
+
+static int icc_test_init(struct kunit *test)
+{
+ struct icc_test_priv *priv;
+ struct icc_node *node;
+ int i, j, ret;
+
+ priv = kunit_kzalloc(test, sizeof(*priv), GFP_KERNEL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, priv);
+ test->priv = priv;
+
+ priv->pdev = kunit_platform_device_alloc(test, "icc-test-dev", -1);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, priv->pdev);
+ KUNIT_ASSERT_EQ(test, kunit_platform_device_add(test, priv->pdev), 0);
+
+ priv->provider.set = icc_test_set;
+ priv->provider.aggregate = icc_test_aggregate;
+ priv->provider.xlate = icc_test_xlate;
+ priv->provider.get_bw = icc_test_get_bw;
+ priv->provider.dev = &priv->pdev->dev;
+ priv->provider.data = priv;
+ INIT_LIST_HEAD(&priv->provider.nodes);
+
+ ret = icc_provider_register(&priv->provider);
+ KUNIT_ASSERT_EQ(test, ret, 0);
+
+ for (i = 0; i < ARRAY_SIZE(test_topology); i++) {
+ const struct test_node_data *data = &test_topology[i];
+
+ node = icc_node_create(data->id);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, node);
+
+ node->name = data->name;
+ icc_node_add(node, &priv->provider);
+ priv->nodes[i] = node;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(test_topology); i++) {
+ const struct test_node_data *data = &test_topology[i];
+ struct icc_node *src = get_node(priv, data->id);
+
+ for (j = 0; j < data->num_links; j++) {
+ ret = icc_link_create(src, data->links[j]);
+ KUNIT_ASSERT_EQ_MSG(test, ret, 0, "Failed to link %s->%d",
+ src->name, data->links[j]);
+ }
+ }
+
+ icc_sync_state(&priv->pdev->dev);
+
+ return 0;
+}
+
+static void icc_test_exit(struct kunit *test)
+{
+ struct icc_test_priv *priv = test->priv;
+
+ icc_nodes_remove(&priv->provider);
+ icc_provider_deregister(&priv->provider);
+}
+
+/*
+ * Helper to construct a mock path.
+ *
+ * Because we are bypassing icc_get(), we must manually link the requests
+ * to the nodes' req_list so that icc_std_aggregate() can discover them.
+ */
+static struct icc_path *icc_test_create_path(struct kunit *test,
+ struct icc_node **nodes, int num)
+{
+ struct icc_path *path;
+ int i;
+
+ path = kunit_kzalloc(test, struct_size(path, reqs, num), GFP_KERNEL);
+ KUNIT_ASSERT_NOT_ERR_OR_NULL(test, path);
+
+ path->num_nodes = num;
+ for (i = 0; i < num; i++) {
+ path->reqs[i].node = nodes[i];
+ hlist_add_head(&path->reqs[i].req_node, &nodes[i]->req_list);
+ }
+ path->name = "mock-path";
+
+ return path;
+}
+
+static void icc_test_destroy_path(struct kunit *test, struct icc_path *path)
+{
+ int i;
+
+ for (i = 0; i < path->num_nodes; i++)
+ hlist_del(&path->reqs[i].req_node);
+
+ kunit_kfree(test, path);
+}
+
+static void icc_test_topology_integrity(struct kunit *test)
+{
+ struct icc_test_priv *priv = test->priv;
+ struct icc_node *cpu = get_node(priv, NODE_CPU);
+ struct icc_node *bus = get_node(priv, NODE_BUS);
+
+ KUNIT_EXPECT_EQ(test, cpu->num_links, 1);
+ KUNIT_EXPECT_PTR_EQ(test, cpu->links[0], bus);
+ KUNIT_EXPECT_PTR_EQ(test, cpu->provider, &priv->provider);
+}
+
+static void icc_test_set_bw(struct kunit *test)
+{
+ struct icc_test_priv *priv = test->priv;
+ struct icc_path *path;
+ struct icc_node *path_nodes[3];
+ int ret;
+
+ /* Path: CPU -> BUS -> DDR */
+ path_nodes[0] = get_node(priv, NODE_CPU);
+ path_nodes[1] = get_node(priv, NODE_BUS);
+ path_nodes[2] = get_node(priv, NODE_DDR);
+
+ path = icc_test_create_path(test, path_nodes, 3);
+
+ ret = icc_enable(path);
+ KUNIT_ASSERT_EQ(test, ret, 0);
+
+ ret = icc_set_bw(path, 1000, 2000);
+ KUNIT_EXPECT_EQ(test, ret, 0);
+
+ KUNIT_EXPECT_EQ(test, path_nodes[0]->avg_bw, 1000);
+ KUNIT_EXPECT_EQ(test, path_nodes[0]->peak_bw, 2000);
+ KUNIT_EXPECT_EQ(test, path_nodes[1]->avg_bw, 1000);
+ KUNIT_EXPECT_EQ(test, path_nodes[1]->peak_bw, 2000);
+
+ icc_set_tag(path, 0xABC);
+ KUNIT_EXPECT_EQ(test, path->reqs[0].tag, 0xABC);
+
+ icc_disable(path);
+ KUNIT_EXPECT_EQ(test, path_nodes[0]->avg_bw, 0);
+
+ icc_test_destroy_path(test, path);
+}
+
+static void icc_test_aggregation(struct kunit *test)
+{
+ struct icc_test_priv *priv = test->priv;
+ struct icc_path *path_cpu, *path_gpu;
+ struct icc_node *nodes_cpu[3], *nodes_gpu[2];
+ struct icc_node *bus = get_node(priv, NODE_BUS);
+ int ret;
+
+ nodes_cpu[0] = get_node(priv, NODE_CPU);
+ nodes_cpu[1] = bus;
+ nodes_cpu[2] = get_node(priv, NODE_DDR);
+ path_cpu = icc_test_create_path(test, nodes_cpu, 3);
+
+ nodes_gpu[0] = get_node(priv, NODE_GPU);
+ nodes_gpu[1] = bus;
+ path_gpu = icc_test_create_path(test, nodes_gpu, 2);
+
+ icc_enable(path_cpu);
+ icc_enable(path_gpu);
+
+ ret = icc_set_bw(path_cpu, 1000, 1000);
+ KUNIT_EXPECT_EQ(test, ret, 0);
+ KUNIT_EXPECT_EQ(test, bus->avg_bw, 1000);
+
+ ret = icc_set_bw(path_gpu, 2000, 2000);
+ KUNIT_EXPECT_EQ(test, ret, 0);
+
+ /* Bus aggregates: CPU(1000) + GPU(2000) */
+ KUNIT_EXPECT_EQ(test, bus->avg_bw, 3000);
+ /* Peak aggregates: max(CPU, GPU) */
+ KUNIT_EXPECT_EQ(test, bus->peak_bw, 2000);
+
+ icc_test_destroy_path(test, path_cpu);
+ icc_test_destroy_path(test, path_gpu);
+}
+
+static void icc_test_bulk_ops(struct kunit *test)
+{
+ struct icc_test_priv *priv = test->priv;
+ struct icc_node *nodes_cpu[3], *nodes_gpu[2];
+ struct icc_bulk_data bulk[2];
+ int ret;
+
+ nodes_cpu[0] = get_node(priv, NODE_CPU);
+ nodes_cpu[1] = get_node(priv, NODE_BUS);
+ nodes_cpu[2] = get_node(priv, NODE_DDR);
+
+ nodes_gpu[0] = get_node(priv, NODE_GPU);
+ nodes_gpu[1] = get_node(priv, NODE_BUS);
+
+ bulk[0].path = icc_test_create_path(test, nodes_cpu, 3);
+ bulk[0].avg_bw = 500;
+ bulk[0].peak_bw = 500;
+
+ bulk[1].path = icc_test_create_path(test, nodes_gpu, 2);
+ bulk[1].avg_bw = 600;
+ bulk[1].peak_bw = 600;
+
+ ret = icc_bulk_set_bw(2, bulk);
+ KUNIT_EXPECT_EQ(test, ret, 0);
+ /* Paths disabled, bandwidth should be 0 */
+ KUNIT_EXPECT_EQ(test, get_node(priv, NODE_BUS)->avg_bw, 0);
+
+ ret = icc_bulk_enable(2, bulk);
+ KUNIT_EXPECT_EQ(test, ret, 0);
+ /* Paths enabled, aggregation applies */
+ KUNIT_EXPECT_EQ(test, get_node(priv, NODE_BUS)->avg_bw, 1100);
+
+ icc_bulk_disable(2, bulk);
+ KUNIT_EXPECT_EQ(test, get_node(priv, NODE_BUS)->avg_bw, 0);
+
+ icc_test_destroy_path(test, bulk[0].path);
+ icc_test_destroy_path(test, bulk[1].path);
+}
+
+static struct kunit_case icc_test_cases[] = {
+ KUNIT_CASE(icc_test_topology_integrity),
+ KUNIT_CASE(icc_test_set_bw),
+ KUNIT_CASE(icc_test_aggregation),
+ KUNIT_CASE(icc_test_bulk_ops),
+ {}
+};
+
+static struct kunit_suite icc_test_suite = {
+ .name = "interconnect",
+ .init = icc_test_init,
+ .exit = icc_test_exit,
+ .test_cases = icc_test_cases,
+};
+
+kunit_test_suite(icc_test_suite);
+
+MODULE_AUTHOR("Kuan-Wei Chiu <visitorckw@gmail.com>");
+MODULE_DESCRIPTION("KUnit tests for the Interconnect framework");
+MODULE_LICENSE("GPL");
projects / thirdparty / linux.git / commitdiff
