selftests: drv-net: add HW timestamping tests

Add simple tests to validate that the driver sets up timestamping
configuration according to what is reported in capabilities.

For RX timestamping we allow driver to fallback to wider scope for
timestamping if filter is applied. That actually means that driver
can enable ptpv2-event when it reports ptpv2-l4-event is supported,
but not vice versa.

Signed-off-by: Vadim Fedorenko <vadim.fedorenko@linux.dev>
Link: https://patch.msgid.link/20250923173310.139623-5-vadim.fedorenko@linux.dev
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

2 files changed, 114 insertions, 0 deletions

diff --git a/tools/testing/selftests/drivers/net/hw/Makefile b/tools/testing/selftests/drivers/net/hw/Makefile
index 5159fd34cb33..ee09a40d532c 100644
--- a/tools/testing/selftests/drivers/net/hw/Makefile
+++ b/tools/testing/selftests/drivers/net/hw/Makefile
@@ -15,6 +15,7 @@ TEST_PROGS = \
 	iou-zcrx.py \
 	irq.py \
 	loopback.sh \
+	nic_timestamp.py \
 	pp_alloc_fail.py \
 	rss_api.py \
 	rss_ctx.py \
diff --git a/tools/testing/selftests/drivers/net/hw/nic_timestamp.py b/tools/testing/selftests/drivers/net/hw/nic_timestamp.py
new file mode 100755
index 000000000000..c1e943d53f19
--- /dev/null
+++ b/tools/testing/selftests/drivers/net/hw/nic_timestamp.py
@@ -0,0 +1,113 @@
+#!/usr/bin/env python3
+# SPDX-License-Identifier: GPL-2.0
+
+"""
+Tests related to configuration of HW timestamping
+"""
+
+import errno
+from lib.py import ksft_run, ksft_exit, ksft_ge, ksft_eq, KsftSkipEx
+from lib.py import NetDrvEnv, EthtoolFamily, NlError
+
+
+def __get_hwtimestamp_support(cfg):
+    """ Retrieve supported configuration information """
+
+    try:
+        tsinfo = cfg.ethnl.tsinfo_get({'header': {'dev-name': cfg.ifname}})
+    except NlError as e:
+        if e.error == errno.EOPNOTSUPP:
+            raise KsftSkipEx("timestamping configuration is not supported") from e
+        raise
+
+    ctx = {}
+    tx = tsinfo.get('tx-types', {})
+    rx = tsinfo.get('rx-filters', {})
+
+    bits = tx.get('bits', {})
+    ctx['tx'] = bits.get('bit', [])
+    bits = rx.get('bits', {})
+    ctx['rx'] = bits.get('bit', [])
+    return ctx
+
+
+def __get_hwtimestamp_config(cfg):
+    """ Retrieve current TS configuration information """
+
+    try:
+        tscfg = cfg.ethnl.tsconfig_get({'header': {'dev-name': cfg.ifname}})
+    except NlError as e:
+        if e.error == errno.EOPNOTSUPP:
+            raise KsftSkipEx("timestamping configuration is not supported via netlink") from e
+        raise
+    return tscfg
+
+
+def __set_hwtimestamp_config(cfg, ts):
+    """ Setup new TS configuration information """
+
+    ts['header'] = {'dev-name': cfg.ifname}
+    try:
+        res = cfg.ethnl.tsconfig_set(ts)
+    except NlError as e:
+        if e.error == errno.EOPNOTSUPP:
+            raise KsftSkipEx("timestamping configuration is not supported via netlink") from e
+        raise
+    return res
+
+
+def test_hwtstamp_tx(cfg):
+    """
+    Test TX timestamp configuration.
+    The driver should apply provided config and report back proper state.
+    """
+
+    orig_tscfg = __get_hwtimestamp_config(cfg)
+    ts = __get_hwtimestamp_support(cfg)
+    tx = ts['tx']
+    for t in tx:
+        tscfg = orig_tscfg
+        tscfg['tx-types']['bits']['bit'] = [t]
+        res = __set_hwtimestamp_config(cfg, tscfg)
+        if res is None:
+            res = __get_hwtimestamp_config(cfg)
+        ksft_eq(res['tx-types']['bits']['bit'], [t])
+    __set_hwtimestamp_config(cfg, orig_tscfg)
+
+
+def test_hwtstamp_rx(cfg):
+    """
+    Test RX timestamp configuration.
+    The filter configuration is taken from the list of supported filters.
+    The driver should apply the config without error and report back proper state.
+    Some extension of the timestamping scope is allowed for PTP filters.
+    """
+
+    orig_tscfg = __get_hwtimestamp_config(cfg)
+    ts = __get_hwtimestamp_support(cfg)
+    rx = ts['rx']
+    for r in rx:
+        tscfg = orig_tscfg
+        tscfg['rx-filters']['bits']['bit'] = [r]
+        res = __set_hwtimestamp_config(cfg, tscfg)
+        if res is None:
+            res = __get_hwtimestamp_config(cfg)
+        if r['index'] == 0 or r['index'] == 1:
+            ksft_eq(res['rx-filters']['bits']['bit'][0]['index'], r['index'])
+        else:
+            # the driver can fallback to some value which has higher coverage for timestamping
+            ksft_ge(res['rx-filters']['bits']['bit'][0]['index'], r['index'])
+    __set_hwtimestamp_config(cfg, orig_tscfg)
+
+
+def main() -> None:
+    """ Ksft boiler plate main """
+
+    with NetDrvEnv(__file__, nsim_test=False) as cfg:
+        cfg.ethnl = EthtoolFamily()
+        ksft_run([test_hwtstamp_tx, test_hwtstamp_rx], args=(cfg,))
+        ksft_exit()
+
+
+if __name__ == "__main__":
+    main()