diff mbox series

[v4] coresight: Add a KUnit test for coresight_find_default_sink()

Message ID 20250312-james-cs-kunit-test-v4-1-ae3dd718a26a@linaro.org (mailing list archive)
State New
Headers show
Series [v4] coresight: Add a KUnit test for coresight_find_default_sink() | expand

Commit Message

James Clark March 12, 2025, 10:31 a.m. UTC 
Add a test to confirm that default sink selection skips over an ETF
and returns an ETR even if it's further away.

This also makes it easier to add new unit tests in the future.

Reviewed-by: Leo Yan <leo.yan@arm.com>
Signed-off-by: James Clark <james.clark@linaro.org>
---
Changes in v4:
- Rename etm to src now that it's not CORESIGHT_DEV_SUBTYPE_SOURCE_PROC
- Remove the now empty src_ops too
- Fix a rebase mistake in the Makefile that removed CTCU
- Link to v3: https://lore.kernel.org/r/20250312-james-cs-kunit-test-v3-1-dcfb69730161@linaro.org

Changes in v3:
- Use CORESIGHT_DEV_SUBTYPE_SOURCE_BUS type instead of the default
  (CORESIGHT_DEV_SUBTYPE_SOURCE_PROC) so that the test still works even
  when TRBE sinks are registered. This also removes the need for the
  fake CPU ID callback.
- Link to v2: https://lore.kernel.org/r/20250305-james-cs-kunit-test-v2-1-83ba682b976c@linaro.org

Changes in v2:
- Let devm free everything rather than doing individual kfrees:
  "Like with managed drivers, KUnit-managed fake devices are
  automatically cleaned up when the test finishes, but can be manually
  cleaned up early with kunit_device_unregister()."
- Link to v1: https://lore.kernel.org/r/20250225164639.522741-1-james.clark@linaro.org
---
 drivers/hwtracing/coresight/Kconfig                |  9 +++
 drivers/hwtracing/coresight/Makefile               |  1 +
 drivers/hwtracing/coresight/coresight-core.c       |  1 +
 .../hwtracing/coresight/coresight-kunit-tests.c    | 74 ++++++++++++++++++++++
 4 files changed, 85 insertions(+)


---
base-commit: 3eadce8308bc8d808fd9e3a9d211c84215087451
change-id: 20250305-james-cs-kunit-test-3af1df2401e6

Best regards,
diff mbox series

Patch

diff --git a/drivers/hwtracing/coresight/Kconfig b/drivers/hwtracing/coresight/Kconfig
index ecd7086a5b83..f064e3d172b3 100644
--- a/drivers/hwtracing/coresight/Kconfig
+++ b/drivers/hwtracing/coresight/Kconfig
@@ -259,4 +259,13 @@  config CORESIGHT_DUMMY
 
 	  To compile this driver as a module, choose M here: the module will be
 	  called coresight-dummy.
+
+config CORESIGHT_KUNIT_TESTS
+	  tristate "Enable Coresight unit tests"
+	  depends on KUNIT
+	  default KUNIT_ALL_TESTS
+	  help
+	    Enable Coresight unit tests. Only useful for development and not
+	    intended for production.
+
 endif
diff --git a/drivers/hwtracing/coresight/Makefile b/drivers/hwtracing/coresight/Makefile
index 8e62c3150aeb..4e6ea5b05b01 100644
--- a/drivers/hwtracing/coresight/Makefile
+++ b/drivers/hwtracing/coresight/Makefile
@@ -53,3 +53,4 @@  obj-$(CONFIG_ULTRASOC_SMB) += ultrasoc-smb.o
 obj-$(CONFIG_CORESIGHT_DUMMY) += coresight-dummy.o
 obj-$(CONFIG_CORESIGHT_CTCU) += coresight-ctcu.o
 coresight-ctcu-y := coresight-ctcu-core.o
+obj-$(CONFIG_CORESIGHT_KUNIT_TESTS) += coresight-kunit-tests.o
diff --git a/drivers/hwtracing/coresight/coresight-core.c b/drivers/hwtracing/coresight/coresight-core.c
index fb43ef6a3b1f..47af75ba7a00 100644
--- a/drivers/hwtracing/coresight/coresight-core.c
+++ b/drivers/hwtracing/coresight/coresight-core.c
@@ -959,6 +959,7 @@  coresight_find_default_sink(struct coresight_device *csdev)
 	}
 	return csdev->def_sink;
 }
+EXPORT_SYMBOL_GPL(coresight_find_default_sink);
 
 static int coresight_remove_sink_ref(struct device *dev, void *data)
 {
diff --git a/drivers/hwtracing/coresight/coresight-kunit-tests.c b/drivers/hwtracing/coresight/coresight-kunit-tests.c
new file mode 100644
index 000000000000..c8f361767c45
--- /dev/null
+++ b/drivers/hwtracing/coresight/coresight-kunit-tests.c
@@ -0,0 +1,74 @@ 
+// SPDX-License-Identifier: GPL-2.0
+
+#include <kunit/test.h>
+#include <kunit/device.h>
+#include <linux/coresight.h>
+
+#include "coresight-priv.h"
+
+static struct coresight_device *coresight_test_device(struct device *dev)
+{
+	struct coresight_device *csdev = devm_kcalloc(dev, 1,
+						     sizeof(struct coresight_device),
+						     GFP_KERNEL);
+	csdev->pdata = devm_kcalloc(dev, 1,
+				   sizeof(struct coresight_platform_data),
+				   GFP_KERNEL);
+	return csdev;
+}
+
+static void test_default_sink(struct kunit *test)
+{
+	/*
+	 * Source -> ETF -> ETR -> CATU
+	 *                   ^
+	 *                   | default
+	 */
+	struct device *dev = kunit_device_register(test, "coresight_kunit");
+	struct coresight_device *src = coresight_test_device(dev),
+				*etf = coresight_test_device(dev),
+				*etr = coresight_test_device(dev),
+				*catu = coresight_test_device(dev);
+	struct coresight_connection conn = {};
+
+	src->type = CORESIGHT_DEV_TYPE_SOURCE;
+	/*
+	 * Don't use CORESIGHT_DEV_SUBTYPE_SOURCE_PROC, that would always return
+	 * a TRBE sink if one is registered.
+	 */
+	src->subtype.source_subtype = CORESIGHT_DEV_SUBTYPE_SOURCE_BUS;
+	etf->type = CORESIGHT_DEV_TYPE_LINKSINK;
+	etf->subtype.sink_subtype = CORESIGHT_DEV_SUBTYPE_SINK_BUFFER;
+	etr->type = CORESIGHT_DEV_TYPE_SINK;
+	etr->subtype.sink_subtype = CORESIGHT_DEV_SUBTYPE_SINK_SYSMEM;
+	catu->type = CORESIGHT_DEV_TYPE_HELPER;
+
+	conn.src_dev = src;
+	conn.dest_dev = etf;
+	coresight_add_out_conn(dev, src->pdata, &conn);
+
+	conn.src_dev = etf;
+	conn.dest_dev = etr;
+	coresight_add_out_conn(dev, etf->pdata, &conn);
+
+	conn.src_dev = etr;
+	conn.dest_dev = catu;
+	coresight_add_out_conn(dev, etr->pdata, &conn);
+
+	KUNIT_ASSERT_PTR_EQ(test, coresight_find_default_sink(src), etr);
+}
+
+static struct kunit_case coresight_testcases[] = {
+	KUNIT_CASE(test_default_sink),
+	{}
+};
+
+static struct kunit_suite coresight_test_suite = {
+	.name = "coresight_test_suite",
+	.test_cases = coresight_testcases,
+};
+
+kunit_test_suites(&coresight_test_suite);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("James Clark <james.clark@linaro.org>");
+MODULE_DESCRIPTION("Arm CoreSight KUnit tests");