1/*
2 * cxgb4_ptp.c:Chelsio PTP support for T5/T6
3 *
4 * Copyright (c) 2003-2017 Chelsio Communications, Inc. All rights reserved.
5 *
6 * This software is available to you under a choice of one of two
7 * licenses. You may choose to be licensed under the terms of the GNU
8 * General Public License (GPL) Version 2, available from the file
9 * COPYING in the main directory of this source tree, or the
10 * OpenIB.org BSD license below:
11 *
12 * Redistribution and use in source and binary forms, with or
13 * without modification, are permitted provided that the following
14 * conditions are met:
15 *
16 * - Redistributions of source code must retain the above
17 * copyright notice, this list of conditions and the following
18 * disclaimer.
19 *
20 * - Redistributions in binary form must reproduce the above
21 * copyright notice, this list of conditions and the following
22 * disclaimer in the documentation and/or other materials
23 * provided with the distribution.
24 *
25 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
26 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
27 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
28 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
29 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
30 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
31 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
32 * SOFTWARE.
33 *
34 * Written by: Atul Gupta (atul.gupta@chelsio.com)
35 */
36
37#include <linux/module.h>
38#include <linux/net_tstamp.h>
39#include <linux/skbuff.h>
40#include <linux/netdevice.h>
41#include <linux/pps_kernel.h>
42#include <linux/ptp_clock_kernel.h>
43#include <linux/ptp_classify.h>
44#include <linux/udp.h>
45
46#include "cxgb4.h"
47#include "t4_hw.h"
48#include "t4_regs.h"
49#include "t4_msg.h"
50#include "t4fw_api.h"
51#include "cxgb4_ptp.h"
52
53/**
54 * cxgb4_ptp_is_ptp_tx - determine whether TX packet is PTP or not
55 * @skb: skb of outgoing ptp request
56 *
57 */
58bool cxgb4_ptp_is_ptp_tx(struct sk_buff *skb)
59{
60 struct udphdr *uh;
61
62 uh = udp_hdr(skb);
63 return skb->len >= PTP_MIN_LENGTH &&
64 skb->len <= PTP_IN_TRANSMIT_PACKET_MAXNUM &&
65 likely(skb->protocol == htons(ETH_P_IP)) &&
66 ip_hdr(skb)->protocol == IPPROTO_UDP &&
67 uh->dest == htons(PTP_EVENT_PORT);
68}
69
70bool is_ptp_enabled(struct sk_buff *skb, struct net_device *dev)
71{
72 struct port_info *pi;
73
74 pi = netdev_priv(dev);
75 return (pi->ptp_enable && cxgb4_xmit_with_hwtstamp(skb) &&
76 cxgb4_ptp_is_ptp_tx(skb));
77}
78
79/**
80 * cxgb4_ptp_is_ptp_rx - determine whether RX packet is PTP or not
81 * @skb: skb of incoming ptp request
82 *
83 */
84bool cxgb4_ptp_is_ptp_rx(struct sk_buff *skb)
85{
86 struct udphdr *uh = (struct udphdr *)(skb->data + ETH_HLEN +
87 IPV4_HLEN(skb->data));
88
89 return uh->dest == htons(PTP_EVENT_PORT) &&
90 uh->source == htons(PTP_EVENT_PORT);
91}
92
93/**
94 * cxgb4_ptp_read_hwstamp - read timestamp for TX event PTP message
95 * @adapter: board private structure
96 * @pi: port private structure
97 *
98 */
99void cxgb4_ptp_read_hwstamp(struct adapter *adapter, struct port_info *pi)
100{
101 struct skb_shared_hwtstamps *skb_ts = NULL;
102 u64 tx_ts;
103
104 skb_ts = skb_hwtstamps(skb: adapter->ptp_tx_skb);
105
106 tx_ts = t4_read_reg(adap: adapter,
107 T5_PORT_REG(pi->port_id, MAC_PORT_TX_TS_VAL_LO));
108
109 tx_ts |= (u64)t4_read_reg(adap: adapter,
110 T5_PORT_REG(pi->port_id,
111 MAC_PORT_TX_TS_VAL_HI)) << 32;
112 skb_ts->hwtstamp = ns_to_ktime(ns: tx_ts);
113 skb_tstamp_tx(orig_skb: adapter->ptp_tx_skb, hwtstamps: skb_ts);
114 dev_kfree_skb_any(skb: adapter->ptp_tx_skb);
115 spin_lock(lock: &adapter->ptp_lock);
116 adapter->ptp_tx_skb = NULL;
117 spin_unlock(lock: &adapter->ptp_lock);
118}
119
120/**
121 * cxgb4_ptprx_timestamping - Enable Timestamp for RX PTP event message
122 * @pi: port private structure
123 * @port: pot number
124 * @mode: RX mode
125 *
126 */
127int cxgb4_ptprx_timestamping(struct port_info *pi, u8 port, u16 mode)
128{
129 struct adapter *adapter = pi->adapter;
130 struct fw_ptp_cmd c;
131 int err;
132
133 memset(&c, 0, sizeof(c));
134 c.op_to_portid = cpu_to_be32(FW_CMD_OP_V(FW_PTP_CMD) |
135 FW_CMD_REQUEST_F |
136 FW_CMD_WRITE_F |
137 FW_PTP_CMD_PORTID_V(port));
138 c.retval_len16 = cpu_to_be32(FW_CMD_LEN16_V(sizeof(c) / 16));
139 c.u.init.sc = FW_PTP_SC_RXTIME_STAMP;
140 c.u.init.mode = cpu_to_be16(mode);
141
142 err = t4_wr_mbox(adap: adapter, mbox: adapter->mbox, cmd: &c, size: sizeof(c), NULL);
143 if (err < 0)
144 dev_err(adapter->pdev_dev,
145 "PTP: %s error %d\n", __func__, -err);
146 return err;
147}
148
149int cxgb4_ptp_txtype(struct adapter *adapter, u8 port)
150{
151 struct fw_ptp_cmd c;
152 int err;
153
154 memset(&c, 0, sizeof(c));
155 c.op_to_portid = cpu_to_be32(FW_CMD_OP_V(FW_PTP_CMD) |
156 FW_CMD_REQUEST_F |
157 FW_CMD_WRITE_F |
158 FW_PTP_CMD_PORTID_V(port));
159 c.retval_len16 = cpu_to_be32(FW_CMD_LEN16_V(sizeof(c) / 16));
160 c.u.init.sc = FW_PTP_SC_TX_TYPE;
161 c.u.init.mode = cpu_to_be16(PTP_TS_NONE);
162
163 err = t4_wr_mbox(adap: adapter, mbox: adapter->mbox, cmd: &c, size: sizeof(c), NULL);
164 if (err < 0)
165 dev_err(adapter->pdev_dev,
166 "PTP: %s error %d\n", __func__, -err);
167
168 return err;
169}
170
171int cxgb4_ptp_redirect_rx_packet(struct adapter *adapter, struct port_info *pi)
172{
173 struct sge *s = &adapter->sge;
174 struct sge_eth_rxq *receive_q = &s->ethrxq[pi->first_qset];
175 struct fw_ptp_cmd c;
176 int err;
177
178 memset(&c, 0, sizeof(c));
179 c.op_to_portid = cpu_to_be32(FW_CMD_OP_V(FW_PTP_CMD) |
180 FW_CMD_REQUEST_F |
181 FW_CMD_WRITE_F |
182 FW_PTP_CMD_PORTID_V(pi->port_id));
183
184 c.retval_len16 = cpu_to_be32(FW_CMD_LEN16_V(sizeof(c) / 16));
185 c.u.init.sc = FW_PTP_SC_RDRX_TYPE;
186 c.u.init.txchan = pi->tx_chan;
187 c.u.init.absid = cpu_to_be16(receive_q->rspq.abs_id);
188
189 err = t4_wr_mbox(adap: adapter, mbox: adapter->mbox, cmd: &c, size: sizeof(c), NULL);
190 if (err < 0)
191 dev_err(adapter->pdev_dev,
192 "PTP: %s error %d\n", __func__, -err);
193 return err;
194}
195
196/**
197 * cxgb4_ptp_adjfine - Adjust frequency of PHC cycle counter
198 * @ptp: ptp clock structure
199 * @scaled_ppm: Desired frequency in scaled parts per billion
200 *
201 * Adjust the frequency of the PHC cycle counter by the indicated amount from
202 * the base frequency.
203 *
204 * Scaled parts per million is ppm with a 16-bit binary fractional field.
205 */
206static int cxgb4_ptp_adjfine(struct ptp_clock_info *ptp, long scaled_ppm)
207{
208 struct adapter *adapter = (struct adapter *)container_of(ptp,
209 struct adapter, ptp_clock_info);
210 s32 ppb = scaled_ppm_to_ppb(ppm: scaled_ppm);
211 struct fw_ptp_cmd c;
212 int err;
213
214 memset(&c, 0, sizeof(c));
215 c.op_to_portid = cpu_to_be32(FW_CMD_OP_V(FW_PTP_CMD) |
216 FW_CMD_REQUEST_F |
217 FW_CMD_WRITE_F |
218 FW_PTP_CMD_PORTID_V(0));
219 c.retval_len16 = cpu_to_be32(FW_CMD_LEN16_V(sizeof(c) / 16));
220 c.u.ts.sc = FW_PTP_SC_ADJ_FREQ;
221 c.u.ts.sign = (ppb < 0) ? 1 : 0;
222 if (ppb < 0)
223 ppb = -ppb;
224 c.u.ts.ppb = cpu_to_be32(ppb);
225
226 err = t4_wr_mbox(adap: adapter, mbox: adapter->mbox, cmd: &c, size: sizeof(c), NULL);
227 if (err < 0)
228 dev_err(adapter->pdev_dev,
229 "PTP: %s error %d\n", __func__, -err);
230
231 return err;
232}
233
234/**
235 * cxgb4_ptp_fineadjtime - Shift the time of the hardware clock
236 * @adapter: board private structure
237 * @delta: Desired change in nanoseconds
238 *
239 * Adjust the timer by resetting the timecounter structure.
240 */
241static int cxgb4_ptp_fineadjtime(struct adapter *adapter, s64 delta)
242{
243 struct fw_ptp_cmd c;
244 int err;
245
246 memset(&c, 0, sizeof(c));
247 c.op_to_portid = cpu_to_be32(FW_CMD_OP_V(FW_PTP_CMD) |
248 FW_CMD_REQUEST_F |
249 FW_CMD_WRITE_F |
250 FW_PTP_CMD_PORTID_V(0));
251 c.retval_len16 = cpu_to_be32(FW_CMD_LEN16_V(sizeof(c) / 16));
252 c.u.ts.sc = FW_PTP_SC_ADJ_FTIME;
253 c.u.ts.sign = (delta < 0) ? 1 : 0;
254 if (delta < 0)
255 delta = -delta;
256 c.u.ts.tm = cpu_to_be64(delta);
257
258 err = t4_wr_mbox(adap: adapter, mbox: adapter->mbox, cmd: &c, size: sizeof(c), NULL);
259 if (err < 0)
260 dev_err(adapter->pdev_dev,
261 "PTP: %s error %d\n", __func__, -err);
262 return err;
263}
264
265/**
266 * cxgb4_ptp_adjtime - Shift the time of the hardware clock
267 * @ptp: ptp clock structure
268 * @delta: Desired change in nanoseconds
269 *
270 * Adjust the timer by resetting the timecounter structure.
271 */
272static int cxgb4_ptp_adjtime(struct ptp_clock_info *ptp, s64 delta)
273{
274 struct adapter *adapter =
275 (struct adapter *)container_of(ptp, struct adapter,
276 ptp_clock_info);
277 struct fw_ptp_cmd c;
278 s64 sign = 1;
279 int err;
280
281 if (delta < 0)
282 sign = -1;
283
284 if (delta * sign > PTP_CLOCK_MAX_ADJTIME) {
285 memset(&c, 0, sizeof(c));
286 c.op_to_portid = cpu_to_be32(FW_CMD_OP_V(FW_PTP_CMD) |
287 FW_CMD_REQUEST_F |
288 FW_CMD_WRITE_F |
289 FW_PTP_CMD_PORTID_V(0));
290 c.retval_len16 = cpu_to_be32(FW_CMD_LEN16_V(sizeof(c) / 16));
291 c.u.ts.sc = FW_PTP_SC_ADJ_TIME;
292 c.u.ts.sign = (delta < 0) ? 1 : 0;
293 if (delta < 0)
294 delta = -delta;
295 c.u.ts.tm = cpu_to_be64(delta);
296
297 err = t4_wr_mbox(adap: adapter, mbox: adapter->mbox, cmd: &c, size: sizeof(c), NULL);
298 if (err < 0)
299 dev_err(adapter->pdev_dev,
300 "PTP: %s error %d\n", __func__, -err);
301 } else {
302 err = cxgb4_ptp_fineadjtime(adapter, delta);
303 }
304
305 return err;
306}
307
308/**
309 * cxgb4_ptp_gettime - Reads the current time from the hardware clock
310 * @ptp: ptp clock structure
311 * @ts: timespec structure to hold the current time value
312 *
313 * Read the timecounter and return the correct value in ns after converting
314 * it into a struct timespec.
315 */
316static int cxgb4_ptp_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
317{
318 struct adapter *adapter = container_of(ptp, struct adapter,
319 ptp_clock_info);
320 u64 ns;
321
322 ns = t4_read_reg(adap: adapter, T5_PORT_REG(0, MAC_PORT_PTP_SUM_LO_A));
323 ns |= (u64)t4_read_reg(adap: adapter,
324 T5_PORT_REG(0, MAC_PORT_PTP_SUM_HI_A)) << 32;
325
326 /* convert to timespec*/
327 *ts = ns_to_timespec64(nsec: ns);
328 return 0;
329}
330
331/**
332 * cxgb4_ptp_settime - Set the current time on the hardware clock
333 * @ptp: ptp clock structure
334 * @ts: timespec containing the new time for the cycle counter
335 *
336 * Reset value to new base value instead of the kernel
337 * wall timer value.
338 */
339static int cxgb4_ptp_settime(struct ptp_clock_info *ptp,
340 const struct timespec64 *ts)
341{
342 struct adapter *adapter = (struct adapter *)container_of(ptp,
343 struct adapter, ptp_clock_info);
344 struct fw_ptp_cmd c;
345 u64 ns;
346 int err;
347
348 memset(&c, 0, sizeof(c));
349 c.op_to_portid = cpu_to_be32(FW_CMD_OP_V(FW_PTP_CMD) |
350 FW_CMD_REQUEST_F |
351 FW_CMD_WRITE_F |
352 FW_PTP_CMD_PORTID_V(0));
353 c.retval_len16 = cpu_to_be32(FW_CMD_LEN16_V(sizeof(c) / 16));
354 c.u.ts.sc = FW_PTP_SC_SET_TIME;
355
356 ns = timespec64_to_ns(ts);
357 c.u.ts.tm = cpu_to_be64(ns);
358
359 err = t4_wr_mbox(adap: adapter, mbox: adapter->mbox, cmd: &c, size: sizeof(c), NULL);
360 if (err < 0)
361 dev_err(adapter->pdev_dev,
362 "PTP: %s error %d\n", __func__, -err);
363
364 return err;
365}
366
367static void cxgb4_init_ptp_timer(struct adapter *adapter)
368{
369 struct fw_ptp_cmd c;
370 int err;
371
372 memset(&c, 0, sizeof(c));
373 c.op_to_portid = cpu_to_be32(FW_CMD_OP_V(FW_PTP_CMD) |
374 FW_CMD_REQUEST_F |
375 FW_CMD_WRITE_F |
376 FW_PTP_CMD_PORTID_V(0));
377 c.retval_len16 = cpu_to_be32(FW_CMD_LEN16_V(sizeof(c) / 16));
378 c.u.scmd.sc = FW_PTP_SC_INIT_TIMER;
379
380 err = t4_wr_mbox(adap: adapter, mbox: adapter->mbox, cmd: &c, size: sizeof(c), NULL);
381 if (err < 0)
382 dev_err(adapter->pdev_dev,
383 "PTP: %s error %d\n", __func__, -err);
384}
385
386/**
387 * cxgb4_ptp_enable - enable or disable an ancillary feature
388 * @ptp: ptp clock structure
389 * @request: Desired resource to enable or disable
390 * @on: Caller passes one to enable or zero to disable
391 *
392 * Enable (or disable) ancillary features of the PHC subsystem.
393 * Currently, no ancillary features are supported.
394 */
395static int cxgb4_ptp_enable(struct ptp_clock_info __always_unused *ptp,
396 struct ptp_clock_request __always_unused *request,
397 int __always_unused on)
398{
399 return -ENOTSUPP;
400}
401
402static const struct ptp_clock_info cxgb4_ptp_clock_info = {
403 .owner = THIS_MODULE,
404 .name = "cxgb4_clock",
405 .max_adj = MAX_PTP_FREQ_ADJ,
406 .n_alarm = 0,
407 .n_ext_ts = 0,
408 .n_per_out = 0,
409 .pps = 0,
410 .adjfine = cxgb4_ptp_adjfine,
411 .adjtime = cxgb4_ptp_adjtime,
412 .gettime64 = cxgb4_ptp_gettime,
413 .settime64 = cxgb4_ptp_settime,
414 .enable = cxgb4_ptp_enable,
415};
416
417/**
418 * cxgb4_ptp_init - initialize PTP for devices which support it
419 * @adapter: board private structure
420 *
421 * This function performs the required steps for enabling PTP support.
422 */
423void cxgb4_ptp_init(struct adapter *adapter)
424{
425 struct timespec64 now;
426 /* no need to create a clock device if we already have one */
427 if (!IS_ERR_OR_NULL(ptr: adapter->ptp_clock))
428 return;
429
430 adapter->ptp_tx_skb = NULL;
431 adapter->ptp_clock_info = cxgb4_ptp_clock_info;
432 spin_lock_init(&adapter->ptp_lock);
433
434 adapter->ptp_clock = ptp_clock_register(info: &adapter->ptp_clock_info,
435 parent: &adapter->pdev->dev);
436 if (IS_ERR_OR_NULL(ptr: adapter->ptp_clock)) {
437 adapter->ptp_clock = NULL;
438 dev_err(adapter->pdev_dev,
439 "PTP %s Clock registration has failed\n", __func__);
440 return;
441 }
442
443 now = ktime_to_timespec64(ktime_get_real());
444 cxgb4_init_ptp_timer(adapter);
445 if (cxgb4_ptp_settime(ptp: &adapter->ptp_clock_info, ts: &now) < 0) {
446 ptp_clock_unregister(ptp: adapter->ptp_clock);
447 adapter->ptp_clock = NULL;
448 }
449}
450
451/**
452 * cxgb4_ptp_stop - disable PTP device and stop the overflow check
453 * @adapter: board private structure
454 *
455 * Stop the PTP support.
456 */
457void cxgb4_ptp_stop(struct adapter *adapter)
458{
459 if (adapter->ptp_tx_skb) {
460 dev_kfree_skb_any(skb: adapter->ptp_tx_skb);
461 adapter->ptp_tx_skb = NULL;
462 }
463
464 if (adapter->ptp_clock) {
465 ptp_clock_unregister(ptp: adapter->ptp_clock);
466 adapter->ptp_clock = NULL;
467 }
468}
469

source code of linux/drivers/net/ethernet/chelsio/cxgb4/cxgb4_ptp.c