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1.. SPDX-License-Identifier: GPL-2.0
2
3====================
4mlx5 devlink support
5====================
6
7This document describes the devlink features implemented by the ``mlx5``
8device driver.
9
10Parameters
11==========
12
13.. list-table:: Generic parameters implemented
14
15 * - Name
16 - Mode
17 - Validation
18 * - ``enable_roce``
19 - driverinit
20 - Type: Boolean
21
22 If the device supports RoCE disablement, RoCE enablement state controls
23 device support for RoCE capability. Otherwise, the control occurs in the
24 driver stack. When RoCE is disabled at the driver level, only raw
25 ethernet QPs are supported.
26 * - ``io_eq_size``
27 - driverinit
28 - The range is between 64 and 4096.
29 * - ``event_eq_size``
30 - driverinit
31 - The range is between 64 and 4096.
32 * - ``max_macs``
33 - driverinit
34 - The range is between 1 and 2^31. Only power of 2 values are supported.
35
36The ``mlx5`` driver also implements the following driver-specific
37parameters.
38
39.. list-table:: Driver-specific parameters implemented
40 :widths: 5 5 5 85
41
42 * - Name
43 - Type
44 - Mode
45 - Description
46 * - ``flow_steering_mode``
47 - string
48 - runtime
49 - Controls the flow steering mode of the driver
50
51 * ``dmfs`` Device managed flow steering. In DMFS mode, the HW
52 steering entities are created and managed through firmware.
53 * ``smfs`` Software managed flow steering. In SMFS mode, the HW
54 steering entities are created and manage through the driver without
55 firmware intervention.
56
57 SMFS mode is faster and provides better rule insertion rate compared to
58 default DMFS mode.
59 * - ``fdb_large_groups``
60 - u32
61 - driverinit
62 - Control the number of large groups (size > 1) in the FDB table.
63
64 * The default value is 15, and the range is between 1 and 1024.
65 * - ``esw_multiport``
66 - Boolean
67 - runtime
68 - Control MultiPort E-Switch shared fdb mode.
69
70 An experimental mode where a single E-Switch is used and all the vports
71 and physical ports on the NIC are connected to it.
72
73 An example is to send traffic from a VF that is created on PF0 to an
74 uplink that is natively associated with the uplink of PF1
75
76 Note: Future devices, ConnectX-8 and onward, will eventually have this
77 as the default to allow forwarding between all NIC ports in a single
78 E-switch environment and the dual E-switch mode will likely get
79 deprecated.
80
81 Default: disabled
82 * - ``esw_port_metadata``
83 - Boolean
84 - runtime
85 - When applicable, disabling eswitch metadata can increase packet rate up
86 to 20% depending on the use case and packet sizes.
87
88 Eswitch port metadata state controls whether to internally tag packets
89 with metadata. Metadata tagging must be enabled for multi-port RoCE,
90 failover between representors and stacked devices. By default metadata is
91 enabled on the supported devices in E-switch. Metadata is applicable only
92 for E-switch in switchdev mode and users may disable it when NONE of the
93 below use cases will be in use:
94 1. HCA is in Dual/multi-port RoCE mode.
95 2. VF/SF representor bonding (Usually used for Live migration)
96 3. Stacked devices
97
98 When metadata is disabled, the above use cases will fail to initialize if
99 users try to enable them.
100
101 Note: Setting this parameter does not take effect immediately. Setting
102 must happen in legacy mode and eswitch port metadata takes effect after
103 enabling switchdev mode.
104 * - ``hairpin_num_queues``
105 - u32
106 - driverinit
107 - We refer to a TC NIC rule that involves forwarding as "hairpin".
108 Hairpin queues are mlx5 hardware specific implementation for hardware
109 forwarding of such packets.
110
111 Control the number of hairpin queues.
112 * - ``hairpin_queue_size``
113 - u32
114 - driverinit
115 - Control the size (in packets) of the hairpin queues.
116
117The ``mlx5`` driver supports reloading via ``DEVLINK_CMD_RELOAD``
118
119Info versions
120=============
121
122The ``mlx5`` driver reports the following versions
123
124.. list-table:: devlink info versions implemented
125 :widths: 5 5 90
126
127 * - Name
128 - Type
129 - Description
130 * - ``fw.psid``
131 - fixed
132 - Used to represent the board id of the device.
133 * - ``fw.version``
134 - stored, running
135 - Three digit major.minor.subminor firmware version number.
136
137Health reporters
138================
139
140tx reporter
141-----------
142The tx reporter is responsible for reporting and recovering of the following three error scenarios:
143
144- tx timeout
145 Report on kernel tx timeout detection.
146 Recover by searching lost interrupts.
147- tx error completion
148 Report on error tx completion.
149 Recover by flushing the tx queue and reset it.
150- tx PTP port timestamping CQ unhealthy
151 Report too many CQEs never delivered on port ts CQ.
152 Recover by flushing and re-creating all PTP channels.
153
154tx reporter also support on demand diagnose callback, on which it provides
155real time information of its send queues status.
156
157User commands examples:
158
159- Diagnose send queues status::
160
161 $ devlink health diagnose pci/0000:82:00.0 reporter tx
162
163.. note::
164 This command has valid output only when interface is up, otherwise the command has empty output.
165
166- Show number of tx errors indicated, number of recover flows ended successfully,
167 is autorecover enabled and graceful period from last recover::
168
169 $ devlink health show pci/0000:82:00.0 reporter tx
170
171rx reporter
172-----------
173The rx reporter is responsible for reporting and recovering of the following two error scenarios:
174
175- rx queues' initialization (population) timeout
176 Population of rx queues' descriptors on ring initialization is done
177 in napi context via triggering an irq. In case of a failure to get
178 the minimum amount of descriptors, a timeout would occur, and
179 descriptors could be recovered by polling the EQ (Event Queue).
180- rx completions with errors (reported by HW on interrupt context)
181 Report on rx completion error.
182 Recover (if needed) by flushing the related queue and reset it.
183
184rx reporter also supports on demand diagnose callback, on which it
185provides real time information of its receive queues' status.
186
187- Diagnose rx queues' status and corresponding completion queue::
188
189 $ devlink health diagnose pci/0000:82:00.0 reporter rx
190
191.. note::
192 This command has valid output only when interface is up. Otherwise, the command has empty output.
193
194- Show number of rx errors indicated, number of recover flows ended successfully,
195 is autorecover enabled, and graceful period from last recover::
196
197 $ devlink health show pci/0000:82:00.0 reporter rx
198
199fw reporter
200-----------
201The fw reporter implements `diagnose` and `dump` callbacks.
202It follows symptoms of fw error such as fw syndrome by triggering
203fw core dump and storing it into the dump buffer.
204The fw reporter diagnose command can be triggered any time by the user to check
205current fw status.
206
207User commands examples:
208
209- Check fw heath status::
210
211 $ devlink health diagnose pci/0000:82:00.0 reporter fw
212
213- Read FW core dump if already stored or trigger new one::
214
215 $ devlink health dump show pci/0000:82:00.0 reporter fw
216
217.. note::
218 This command can run only on the PF which has fw tracer ownership,
219 running it on other PF or any VF will return "Operation not permitted".
220
221fw fatal reporter
222-----------------
223The fw fatal reporter implements `dump` and `recover` callbacks.
224It follows fatal errors indications by CR-space dump and recover flow.
225The CR-space dump uses vsc interface which is valid even if the FW command
226interface is not functional, which is the case in most FW fatal errors.
227The recover function runs recover flow which reloads the driver and triggers fw
228reset if needed.
229On firmware error, the health buffer is dumped into the dmesg. The log
230level is derived from the error's severity (given in health buffer).
231
232User commands examples:
233
234- Run fw recover flow manually::
235
236 $ devlink health recover pci/0000:82:00.0 reporter fw_fatal
237
238- Read FW CR-space dump if already stored or trigger new one::
239
240 $ devlink health dump show pci/0000:82:00.1 reporter fw_fatal
241
242.. note::
243 This command can run only on PF.
244
245vnic reporter
246-------------
247The vnic reporter implements only the `diagnose` callback.
248It is responsible for querying the vnic diagnostic counters from fw and displaying
249them in realtime.
250
251Description of the vnic counters:
252
253- total_error_queues
254 number of queues in an error state due to
255 an async error or errored command.
256- send_queue_priority_update_flow
257 number of QP/SQ priority/SL update events.
258- cq_overrun
259 number of times CQ entered an error state due to an overflow.
260- async_eq_overrun
261 number of times an EQ mapped to async events was overrun.
262- comp_eq_overrun
263 number of times an EQ mapped to completion events was
264 overrun.
265- quota_exceeded_command
266 number of commands issued and failed due to quota exceeded.
267- invalid_command
268 number of commands issued and failed dues to any reason other than quota
269 exceeded.
270- nic_receive_steering_discard
271 number of packets that completed RX flow
272 steering but were discarded due to a mismatch in flow table.
273- generated_pkt_steering_fail
274 number of packets generated by the VNIC experiencing unexpected steering
275 failure (at any point in steering flow).
276- handled_pkt_steering_fail
277 number of packets handled by the VNIC experiencing unexpected steering
278 failure (at any point in steering flow owned by the VNIC, including the FDB
279 for the eswitch owner).
280
281User commands examples:
282
283- Diagnose PF/VF vnic counters::
284
285 $ devlink health diagnose pci/0000:82:00.1 reporter vnic
286
287- Diagnose representor vnic counters (performed by supplying devlink port of the
288 representor, which can be obtained via devlink port command)::
289
290 $ devlink health diagnose pci/0000:82:00.1/65537 reporter vnic
291
292.. note::
293 This command can run over all interfaces such as PF/VF and representor ports.