Extend loopback_nsim.py with netdevsim-specific tests for CMIS module loopback. These tests seed the EEPROM via debugfs and verify register-level behavior.
Tests cover: no-module GET, all/partial capability reporting, EEPROM byte verification for enable/disable and direction switching, rejection of unsupported directions, rejection without CMIS support, and combined MAC + MODULE dump. Signed-off-by: Björn Töpel <[email protected]> --- .../selftests/drivers/net/hw/loopback_nsim.py | 207 +++++++++++++++++- 1 file changed, 206 insertions(+), 1 deletion(-) diff --git a/tools/testing/selftests/drivers/net/hw/loopback_nsim.py b/tools/testing/selftests/drivers/net/hw/loopback_nsim.py index 5edc999d920b..26e74718098a 100755 --- a/tools/testing/selftests/drivers/net/hw/loopback_nsim.py +++ b/tools/testing/selftests/drivers/net/hw/loopback_nsim.py @@ -1,10 +1,13 @@ #!/usr/bin/env python3 # SPDX-License-Identifier: GPL-2.0 -"""Netdevsim-specific tests for MAC loopback via ethtool_ops. +"""Netdevsim-specific tests for ethtool loopback. Verifies that MAC loopback entries appear in dumps, that SET operations update state correctly (both via GET and debugfs). + +Seeds the CMIS EEPROM via debugfs and verifies register-level +behavior that can only be checked with controlled EEPROM contents. """ import errno @@ -15,6 +18,20 @@ from lib.py import KsftSkipEx, KsftFailEx, ksft_disruptive from lib.py import EthtoolFamily, NlError from lib.py import NetDrvEnv, ip, defer +# CMIS register constants matching net/ethtool/cmis_loopback.c +SFF8024_ID_QSFP_DD = 0x18 + +# Page 01h, Byte 142: bit 5 = Page 13h supported +CMIS_DIAG_PAGE13_BIT = 1 << 5 + +# Page 13h, Byte 128: loopback capability bits +CMIS_LB_CAP_MEDIA_OUTPUT = 1 << 0 +CMIS_LB_CAP_MEDIA_INPUT = 1 << 1 +CMIS_LB_CAP_HOST_OUTPUT = 1 << 2 +CMIS_LB_CAP_HOST_INPUT = 1 << 3 +CMIS_LB_CAP_ALL = (CMIS_LB_CAP_MEDIA_OUTPUT | CMIS_LB_CAP_MEDIA_INPUT | + CMIS_LB_CAP_HOST_OUTPUT | CMIS_LB_CAP_HOST_INPUT) + # Direction flags as YNL returns them DIR_NONE = set() DIR_NEAR_END = {'near-end'} @@ -35,6 +52,54 @@ def _dfs_write_u32(cfg, path, val): f.write(str(val)) +def _nsim_write_page_byte(cfg, page, offset, value): + """Write a single byte to a netdevsim EEPROM page via debugfs.""" + if offset < 128: + page_file = os.path.join(_nsim_dfs_path(cfg), + "ethtool/module/pages/0") + file_offset = offset + else: + page_file = os.path.join(_nsim_dfs_path(cfg), + f"ethtool/module/pages/{page}") + file_offset = offset - 128 + + with open(page_file, "r+b") as f: + f.seek(file_offset) + f.write(bytes([value])) + + +def _nsim_read_page_byte(cfg, page, offset): + """Read a single byte from a netdevsim EEPROM page via debugfs.""" + if offset < 128: + page_file = os.path.join(_nsim_dfs_path(cfg), + "ethtool/module/pages/0") + file_offset = offset + else: + page_file = os.path.join(_nsim_dfs_path(cfg), + f"ethtool/module/pages/{page}") + file_offset = offset - 128 + + with open(page_file, "rb") as f: + f.seek(file_offset) + return f.read(1)[0] + + +def _nsim_seed_cmis(cfg, caps=CMIS_LB_CAP_ALL): + """Seed the netdevsim EEPROM with CMIS module identity and + loopback capabilities. + """ + _nsim_write_page_byte(cfg, 0x00, 0, SFF8024_ID_QSFP_DD) + _nsim_write_page_byte(cfg, 0x01, 0x8e, CMIS_DIAG_PAGE13_BIT) + _nsim_write_page_byte(cfg, 0x13, 0x80, caps) + + +def _nsim_clear_cmis(cfg): + """Clear CMIS identity bytes left by previous tests.""" + _nsim_write_page_byte(cfg, 0x00, 0, 0) + _nsim_write_page_byte(cfg, 0x01, 0x8e, 0) + _nsim_write_page_byte(cfg, 0x13, 0x80, 0) + + def _get_loopback(cfg): results = cfg.ethnl.loopback_get({ 'header': {'dev-index': cfg.ifindex} @@ -118,6 +183,138 @@ def test_set_mac_unknown_name(cfg): "Expected EOPNOTSUPP for unknown name") +def test_get_no_module(cfg): + """GET on a device with no CMIS module returns no module entries.""" + _nsim_clear_cmis(cfg) + + entries = _get_loopback(cfg) + mod_entries = [e for e in entries if e['component'] == 'module'] + ksft_eq(len(mod_entries), 0, "Expected no module entries without CMIS module") + + +def test_get_all_caps(cfg): + """GET with all four CMIS loopback capabilities seeded.""" + _nsim_seed_cmis(cfg, CMIS_LB_CAP_ALL) + + entries = _get_loopback(cfg) + mod_entries = [e for e in entries if e['component'] == 'module'] + + # Expect 2 entries (one per name), each with both directions + ksft_eq(len(mod_entries), 2, "Expected 2 module loopback entries") + + host = [e for e in mod_entries if e['name'] == 'cmis-host'] + media = [e for e in mod_entries if e['name'] == 'cmis-media'] + ksft_eq(len(host), 1, "Expected 1 cmis-host entry") + ksft_eq(len(media), 1, "Expected 1 cmis-media entry") + + ksft_eq(host[0]['supported'], DIR_NEAR_END | DIR_FAR_END) + ksft_eq(media[0]['supported'], DIR_NEAR_END | DIR_FAR_END) + + for e in mod_entries: + ksft_eq(e['direction'], DIR_NONE, + f"Expected direction=off for {e['name']}") + + +def test_get_partial_caps(cfg): + """GET with only host-input capability advertised.""" + _nsim_seed_cmis(cfg, CMIS_LB_CAP_HOST_INPUT) + + entries = _get_loopback(cfg) + mod_entries = [e for e in entries if e['component'] == 'module'] + ksft_eq(len(mod_entries), 1, "Expected 1 module loopback entry") + ksft_eq(mod_entries[0]['name'], 'cmis-host') + ksft_eq(mod_entries[0]['supported'], DIR_NEAR_END) + + +@ksft_disruptive +def test_set_verify_eeprom(cfg): + """SET near-end and verify the EEPROM control byte directly.""" + _nsim_seed_cmis(cfg, CMIS_LB_CAP_ALL) + + ip(f"link set dev {cfg.ifname} down") + defer(ip, f"link set dev {cfg.ifname} up") + + _set_loopback(cfg, 'module', 'cmis-host', 'near-end') + defer(_set_loopback, cfg, 'module', 'cmis-host', 0) + + # Host Side Input = Page 13h, Byte 183 + val = _nsim_read_page_byte(cfg, 0x13, 183) + ksft_eq(val, 0xff, "Host Side Input control byte should be 0xff") + + # Disable and verify + _set_loopback(cfg, 'module', 'cmis-host', 0) + val = _nsim_read_page_byte(cfg, 0x13, 183) + ksft_eq(val, 0x00, "Host Side Input should be 0x00 after disable") + + +@ksft_disruptive +def test_set_direction_switch_eeprom(cfg): + """Switch directions and verify both EEPROM bytes.""" + _nsim_seed_cmis(cfg, CMIS_LB_CAP_ALL) + + ip(f"link set dev {cfg.ifname} down") + defer(ip, f"link set dev {cfg.ifname} up") + + _set_loopback(cfg, 'module', 'cmis-host', 'near-end') + defer(_set_loopback, cfg, 'module', 'cmis-host', 0) + + # Switch to far-end + _set_loopback(cfg, 'module', 'cmis-host', 'far-end') + + # Near-end (Host Input, Byte 183) should be disabled + val = _nsim_read_page_byte(cfg, 0x13, 183) + ksft_eq(val, 0x00, "Near-end should be disabled after switch") + # Far-end (Host Output, Byte 182) should be enabled + val = _nsim_read_page_byte(cfg, 0x13, 182) + ksft_eq(val, 0xff, "Far-end should be enabled after switch") + + +@ksft_disruptive +def test_set_unsupported_direction(cfg): + """SET with unsupported direction should fail.""" + _nsim_seed_cmis(cfg, CMIS_LB_CAP_HOST_INPUT) # only near-end + + ip(f"link set dev {cfg.ifname} down") + defer(ip, f"link set dev {cfg.ifname} up") + + try: + _set_loopback(cfg, 'module', 'cmis-host', 'far-end') + raise KsftFailEx("Should have rejected unsupported direction") + except NlError as e: + ksft_eq(e.error, errno.EOPNOTSUPP, + "Expected EOPNOTSUPP for unsupported direction") + + +@ksft_disruptive +def test_set_no_cmis(cfg): + """SET on a device without CMIS loopback support should fail.""" + _nsim_clear_cmis(cfg) + + ip(f"link set dev {cfg.ifname} down") + defer(ip, f"link set dev {cfg.ifname} up") + + try: + _set_loopback(cfg, 'module', 'cmis-host', 'near-end') + raise KsftFailEx("Should have rejected SET without CMIS support") + except NlError as e: + ksft_eq(e.error, errno.EOPNOTSUPP, + "Expected EOPNOTSUPP without CMIS support") + + +def test_combined_dump(cfg): + """Dump should return both MAC and MODULE entries.""" + _nsim_seed_cmis(cfg, CMIS_LB_CAP_ALL) + defer(_nsim_clear_cmis, cfg) + + entries = _get_loopback(cfg) + mac_entries = [e for e in entries if e['component'] == 'mac'] + mod_entries = [e for e in entries if e['component'] == 'module'] + + ksft_eq(len(mac_entries), 1, "Expected 1 MAC entry") + ksft_eq(len(mod_entries), 2, "Expected 2 MODULE entries") + ksft_eq(mac_entries[0]['name'], 'mac') + + def main() -> None: with NetDrvEnv(__file__) as cfg: cfg.ethnl = EthtoolFamily() @@ -127,6 +324,14 @@ def main() -> None: test_set_mac_near_end, test_set_mac_disable, test_set_mac_unknown_name, + test_get_no_module, + test_get_all_caps, + test_get_partial_caps, + test_set_verify_eeprom, + test_set_direction_switch_eeprom, + test_set_unsupported_direction, + test_set_no_cmis, + test_combined_dump, ], args=(cfg, )) ksft_exit() -- 2.53.0
