2 * Fast Ethernet Controller (ENET) PTP driver for MX6x.
4 * Copyright (C) 2012 Freescale Semiconductor, Inc.
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms and conditions of the GNU General Public License,
8 * version 2, as published by the Free Software Foundation.
10 * This program is distributed in the hope it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
15 * You should have received a copy of the GNU General Public License along with
16 * this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
20 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
22 #include <linux/module.h>
23 #include <linux/kernel.h>
24 #include <linux/string.h>
25 #include <linux/ptrace.h>
26 #include <linux/errno.h>
27 #include <linux/ioport.h>
28 #include <linux/slab.h>
29 #include <linux/interrupt.h>
30 #include <linux/pci.h>
31 #include <linux/delay.h>
32 #include <linux/netdevice.h>
33 #include <linux/etherdevice.h>
34 #include <linux/skbuff.h>
35 #include <linux/spinlock.h>
36 #include <linux/workqueue.h>
37 #include <linux/bitops.h>
39 #include <linux/irq.h>
40 #include <linux/clk.h>
41 #include <linux/platform_device.h>
42 #include <linux/phy.h>
43 #include <linux/fec.h>
45 #include <linux/of_device.h>
46 #include <linux/of_gpio.h>
47 #include <linux/of_net.h>
51 /* FEC 1588 register bits */
52 #define FEC_T_CTRL_SLAVE 0x00002000
53 #define FEC_T_CTRL_CAPTURE 0x00000800
54 #define FEC_T_CTRL_RESTART 0x00000200
55 #define FEC_T_CTRL_PERIOD_RST 0x00000030
56 #define FEC_T_CTRL_PERIOD_EN 0x00000010
57 #define FEC_T_CTRL_ENABLE 0x00000001
59 #define FEC_T_INC_MASK 0x0000007f
60 #define FEC_T_INC_OFFSET 0
61 #define FEC_T_INC_CORR_MASK 0x00007f00
62 #define FEC_T_INC_CORR_OFFSET 8
64 #define FEC_T_CTRL_PINPER 0x00000080
65 #define FEC_T_TF0_MASK 0x00000001
66 #define FEC_T_TF0_OFFSET 0
67 #define FEC_T_TF1_MASK 0x00000002
68 #define FEC_T_TF1_OFFSET 1
69 #define FEC_T_TF2_MASK 0x00000004
70 #define FEC_T_TF2_OFFSET 2
71 #define FEC_T_TF3_MASK 0x00000008
72 #define FEC_T_TF3_OFFSET 3
73 #define FEC_T_TDRE_MASK 0x00000001
74 #define FEC_T_TDRE_OFFSET 0
75 #define FEC_T_TMODE_MASK 0x0000003C
76 #define FEC_T_TMODE_OFFSET 2
77 #define FEC_T_TIE_MASK 0x00000040
78 #define FEC_T_TIE_OFFSET 6
79 #define FEC_T_TF_MASK 0x00000080
80 #define FEC_T_TF_OFFSET 7
82 #define FEC_ATIME_CTRL 0x400
83 #define FEC_ATIME 0x404
84 #define FEC_ATIME_EVT_OFFSET 0x408
85 #define FEC_ATIME_EVT_PERIOD 0x40c
86 #define FEC_ATIME_CORR 0x410
87 #define FEC_ATIME_INC 0x414
88 #define FEC_TS_TIMESTAMP 0x418
90 #define FEC_TGSR 0x604
91 #define FEC_TCSR(n) (0x608 + n * 0x08)
92 #define FEC_TCCR(n) (0x60C + n * 0x08)
93 #define MAX_TIMER_CHANNEL 3
94 #define FEC_TMODE_TOGGLE 0x05
95 #define FEC_HIGH_PULSE 0x0F
97 #define FEC_CC_MULT (1 << 31)
98 #define FEC_COUNTER_PERIOD (1 << 31)
99 #define PPS_OUPUT_RELOAD_PERIOD NSEC_PER_SEC
100 #define FEC_CHANNLE_0 0
101 #define DEFAULT_PPS_CHANNEL FEC_CHANNLE_0
105 * @fep: the fec_enet_private structure handle
106 * @enable: enable the channel pps output
108 * This function enble the PPS ouput on the timer channel.
110 static int fec_ptp_enable_pps(struct fec_enet_private
*fep
, uint enable
)
120 if (!(fep
->hwts_tx_en
|| fep
->hwts_rx_en
)) {
121 dev_err(&fep
->pdev
->dev
, "No ptp stack is running\n");
125 if (fep
->pps_enable
== enable
)
128 fep
->pps_channel
= DEFAULT_PPS_CHANNEL
;
129 fep
->reload_period
= PPS_OUPUT_RELOAD_PERIOD
;
132 spin_lock_irqsave(&fep
->tmreg_lock
, flags
);
135 /* clear capture or output compare interrupt status if have.
137 writel(FEC_T_TF_MASK
, fep
->hwp
+ FEC_TCSR(fep
->pps_channel
));
139 /* It is recommended to doulbe check the TMODE field in the
140 * TCSR register to be cleared before the first compare counter
141 * is written into TCCR register. Just add a double check.
143 val
= readl(fep
->hwp
+ FEC_TCSR(fep
->pps_channel
));
145 val
&= ~(FEC_T_TMODE_MASK
);
146 writel(val
, fep
->hwp
+ FEC_TCSR(fep
->pps_channel
));
147 val
= readl(fep
->hwp
+ FEC_TCSR(fep
->pps_channel
));
148 } while (val
& FEC_T_TMODE_MASK
);
150 /* Dummy read counter to update the counter */
151 timecounter_read(&fep
->tc
);
152 /* We want to find the first compare event in the next
153 * second point. So we need to know what the ptp time
154 * is now and how many nanoseconds is ahead to get next second.
155 * The remaining nanosecond ahead before the next second would be
156 * NSEC_PER_SEC - ts.tv_nsec. Add the remaining nanoseconds
157 * to current timer would be next second.
159 tempval
= readl(fep
->hwp
+ FEC_ATIME_CTRL
);
160 tempval
|= FEC_T_CTRL_CAPTURE
;
161 writel(tempval
, fep
->hwp
+ FEC_ATIME_CTRL
);
163 tempval
= readl(fep
->hwp
+ FEC_ATIME
);
164 /* Convert the ptp local counter to 1588 timestamp */
165 ns
= timecounter_cyc2time(&fep
->tc
, tempval
);
166 ts
.tv_sec
= div_u64_rem(ns
, 1000000000ULL, &remainder
);
167 ts
.tv_nsec
= remainder
;
169 /* The tempval is less than 3 seconds, and so val is less than
170 * 4 seconds. No overflow for 32bit calculation.
172 val
= NSEC_PER_SEC
- (u32
)ts
.tv_nsec
+ tempval
;
174 /* Need to consider the situation that the current time is
175 * very close to the second point, which means NSEC_PER_SEC
176 * - ts.tv_nsec is close to be zero(For example 20ns); Since the timer
177 * is still running when we calculate the first compare event, it is
178 * possible that the remaining nanoseonds run out before the compare
179 * counter is calculated and written into TCCR register. To avoid
180 * this possibility, we will set the compare event to be the next
181 * of next second. The current setting is 31-bit timer and wrap
182 * around over 2 seconds. So it is okay to set the next of next
183 * seond for the timer.
187 /* We add (2 * NSEC_PER_SEC - (u32)ts.tv_nsec) to current
188 * ptp counter, which maybe cause 32-bit wrap. Since the
189 * (NSEC_PER_SEC - (u32)ts.tv_nsec) is less than 2 second.
190 * We can ensure the wrap will not cause issue. If the offset
191 * is bigger than fep->cc.mask would be a error.
194 writel(val
, fep
->hwp
+ FEC_TCCR(fep
->pps_channel
));
196 /* Calculate the second the compare event timestamp */
197 fep
->next_counter
= (val
+ fep
->reload_period
) & fep
->cc
.mask
;
199 /* * Enable compare event when overflow */
200 val
= readl(fep
->hwp
+ FEC_ATIME_CTRL
);
201 val
|= FEC_T_CTRL_PINPER
;
202 writel(val
, fep
->hwp
+ FEC_ATIME_CTRL
);
204 /* Compare channel setting. */
205 val
= readl(fep
->hwp
+ FEC_TCSR(fep
->pps_channel
));
206 val
|= (1 << FEC_T_TF_OFFSET
| 1 << FEC_T_TIE_OFFSET
);
207 val
&= ~(1 << FEC_T_TDRE_OFFSET
);
208 val
&= ~(FEC_T_TMODE_MASK
);
209 val
|= (FEC_HIGH_PULSE
<< FEC_T_TMODE_OFFSET
);
210 writel(val
, fep
->hwp
+ FEC_TCSR(fep
->pps_channel
));
212 /* Write the second compare event timestamp and calculate
213 * the third timestamp. Refer the TCCR register detail in the spec.
215 writel(fep
->next_counter
, fep
->hwp
+ FEC_TCCR(fep
->pps_channel
));
216 fep
->next_counter
= (fep
->next_counter
+ fep
->reload_period
) & fep
->cc
.mask
;
218 writel(0, fep
->hwp
+ FEC_TCSR(fep
->pps_channel
));
221 fep
->pps_enable
= enable
;
222 spin_unlock_irqrestore(&fep
->tmreg_lock
, flags
);
228 * fec_ptp_read - read raw cycle counter (to be used by time counter)
229 * @cc: the cyclecounter structure
231 * this function reads the cyclecounter registers and is called by the
232 * cyclecounter structure used to construct a ns counter from the
233 * arbitrary fixed point registers
235 static cycle_t
fec_ptp_read(const struct cyclecounter
*cc
)
237 struct fec_enet_private
*fep
=
238 container_of(cc
, struct fec_enet_private
, cc
);
239 const struct platform_device_id
*id_entry
=
240 platform_get_device_id(fep
->pdev
);
243 tempval
= readl(fep
->hwp
+ FEC_ATIME_CTRL
);
244 tempval
|= FEC_T_CTRL_CAPTURE
;
245 writel(tempval
, fep
->hwp
+ FEC_ATIME_CTRL
);
247 if (id_entry
->driver_data
& FEC_QUIRK_BUG_CAPTURE
)
250 return readl(fep
->hwp
+ FEC_ATIME
);
254 * fec_ptp_start_cyclecounter - create the cycle counter from hw
255 * @ndev: network device
257 * this function initializes the timecounter and cyclecounter
258 * structures for use in generated a ns counter from the arbitrary
259 * fixed point cycles registers in the hardware.
261 void fec_ptp_start_cyclecounter(struct net_device
*ndev
)
263 struct fec_enet_private
*fep
= netdev_priv(ndev
);
267 inc
= 1000000000 / fep
->cycle_speed
;
269 /* grab the ptp lock */
270 spin_lock_irqsave(&fep
->tmreg_lock
, flags
);
273 writel(inc
<< FEC_T_INC_OFFSET
, fep
->hwp
+ FEC_ATIME_INC
);
275 /* use 31-bit timer counter */
276 writel(FEC_COUNTER_PERIOD
, fep
->hwp
+ FEC_ATIME_EVT_PERIOD
);
278 writel(FEC_T_CTRL_ENABLE
| FEC_T_CTRL_PERIOD_RST
,
279 fep
->hwp
+ FEC_ATIME_CTRL
);
281 memset(&fep
->cc
, 0, sizeof(fep
->cc
));
282 fep
->cc
.read
= fec_ptp_read
;
283 fep
->cc
.mask
= CLOCKSOURCE_MASK(31);
285 fep
->cc
.mult
= FEC_CC_MULT
;
287 /* reset the ns time counter */
288 timecounter_init(&fep
->tc
, &fep
->cc
, ktime_to_ns(ktime_get_real()));
290 spin_unlock_irqrestore(&fep
->tmreg_lock
, flags
);
294 * fec_ptp_adjfreq - adjust ptp cycle frequency
295 * @ptp: the ptp clock structure
296 * @ppb: parts per billion adjustment from base
298 * Adjust the frequency of the ptp cycle counter by the
299 * indicated ppb from the base frequency.
301 * Because ENET hardware frequency adjust is complex,
302 * using software method to do that.
304 static int fec_ptp_adjfreq(struct ptp_clock_info
*ptp
, s32 ppb
)
309 u32 corr_inc
, corr_period
;
313 struct fec_enet_private
*fep
=
314 container_of(ptp
, struct fec_enet_private
, ptp_caps
);
324 /* In theory, corr_inc/corr_period = ppb/NSEC_PER_SEC;
325 * Try to find the corr_inc between 1 to fep->ptp_inc to
326 * meet adjustment requirement.
329 rhs
= (u64
)ppb
* (u64
)fep
->ptp_inc
;
330 for (i
= 1; i
<= fep
->ptp_inc
; i
++) {
333 corr_period
= div_u64(lhs
, rhs
);
338 /* Not found? Set it to high value - double speed
339 * correct in every clock step.
341 if (i
> fep
->ptp_inc
) {
342 corr_inc
= fep
->ptp_inc
;
347 corr_ns
= fep
->ptp_inc
- corr_inc
;
349 corr_ns
= fep
->ptp_inc
+ corr_inc
;
351 spin_lock_irqsave(&fep
->tmreg_lock
, flags
);
353 tmp
= readl(fep
->hwp
+ FEC_ATIME_INC
) & FEC_T_INC_MASK
;
354 tmp
|= corr_ns
<< FEC_T_INC_CORR_OFFSET
;
355 writel(tmp
, fep
->hwp
+ FEC_ATIME_INC
);
356 writel(corr_period
, fep
->hwp
+ FEC_ATIME_CORR
);
357 /* dummy read to update the timer. */
358 timecounter_read(&fep
->tc
);
360 spin_unlock_irqrestore(&fep
->tmreg_lock
, flags
);
367 * @ptp: the ptp clock structure
368 * @delta: offset to adjust the cycle counter by
370 * adjust the timer by resetting the timecounter structure.
372 static int fec_ptp_adjtime(struct ptp_clock_info
*ptp
, s64 delta
)
374 struct fec_enet_private
*fep
=
375 container_of(ptp
, struct fec_enet_private
, ptp_caps
);
380 spin_lock_irqsave(&fep
->tmreg_lock
, flags
);
382 now
= timecounter_read(&fep
->tc
);
385 /* Get the timer value based on adjusted timestamp.
386 * Update the counter with the masked value.
388 counter
= now
& fep
->cc
.mask
;
389 writel(counter
, fep
->hwp
+ FEC_ATIME
);
391 /* reset the timecounter */
392 timecounter_init(&fep
->tc
, &fep
->cc
, now
);
394 spin_unlock_irqrestore(&fep
->tmreg_lock
, flags
);
401 * @ptp: the ptp clock structure
402 * @ts: timespec structure to hold the current time value
404 * read the timecounter and return the correct value on ns,
405 * after converting it into a struct timespec.
407 static int fec_ptp_gettime(struct ptp_clock_info
*ptp
, struct timespec
*ts
)
409 struct fec_enet_private
*adapter
=
410 container_of(ptp
, struct fec_enet_private
, ptp_caps
);
415 spin_lock_irqsave(&adapter
->tmreg_lock
, flags
);
416 ns
= timecounter_read(&adapter
->tc
);
417 spin_unlock_irqrestore(&adapter
->tmreg_lock
, flags
);
419 ts
->tv_sec
= div_u64_rem(ns
, 1000000000ULL, &remainder
);
420 ts
->tv_nsec
= remainder
;
427 * @ptp: the ptp clock structure
428 * @ts: the timespec containing the new time for the cycle counter
430 * reset the timecounter to use a new base value instead of the kernel
433 static int fec_ptp_settime(struct ptp_clock_info
*ptp
,
434 const struct timespec
*ts
)
436 struct fec_enet_private
*fep
=
437 container_of(ptp
, struct fec_enet_private
, ptp_caps
);
443 mutex_lock(&fep
->ptp_clk_mutex
);
444 /* Check the ptp clock */
445 if (!fep
->ptp_clk_on
) {
446 mutex_unlock(&fep
->ptp_clk_mutex
);
450 ns
= ts
->tv_sec
* 1000000000ULL;
452 /* Get the timer value based on timestamp.
453 * Update the counter with the masked value.
455 counter
= ns
& fep
->cc
.mask
;
457 spin_lock_irqsave(&fep
->tmreg_lock
, flags
);
458 writel(counter
, fep
->hwp
+ FEC_ATIME
);
459 timecounter_init(&fep
->tc
, &fep
->cc
, ns
);
460 spin_unlock_irqrestore(&fep
->tmreg_lock
, flags
);
461 mutex_unlock(&fep
->ptp_clk_mutex
);
467 * @ptp: the ptp clock structure
468 * @rq: the requested feature to change
469 * @on: whether to enable or disable the feature
472 static int fec_ptp_enable(struct ptp_clock_info
*ptp
,
473 struct ptp_clock_request
*rq
, int on
)
475 struct fec_enet_private
*fep
=
476 container_of(ptp
, struct fec_enet_private
, ptp_caps
);
479 if (rq
->type
== PTP_CLK_REQ_PPS
) {
480 ret
= fec_ptp_enable_pps(fep
, on
);
488 * fec_ptp_hwtstamp_ioctl - control hardware time stamping
489 * @ndev: pointer to net_device
491 * @cmd: particular ioctl requested
493 int fec_ptp_set(struct net_device
*ndev
, struct ifreq
*ifr
)
495 struct fec_enet_private
*fep
= netdev_priv(ndev
);
497 struct hwtstamp_config config
;
499 if (copy_from_user(&config
, ifr
->ifr_data
, sizeof(config
)))
502 /* reserved for future extensions */
506 switch (config
.tx_type
) {
507 case HWTSTAMP_TX_OFF
:
517 switch (config
.rx_filter
) {
518 case HWTSTAMP_FILTER_NONE
:
521 config
.rx_filter
= HWTSTAMP_FILTER_NONE
;
526 * register RXMTRL must be set in order to do V1 packets,
527 * therefore it is not possible to time stamp both V1 Sync and
528 * Delay_Req messages and hardware does not support
529 * timestamping all packets => return error
532 config
.rx_filter
= HWTSTAMP_FILTER_ALL
;
536 return copy_to_user(ifr
->ifr_data
, &config
, sizeof(config
)) ?
540 int fec_ptp_get(struct net_device
*ndev
, struct ifreq
*ifr
)
542 struct fec_enet_private
*fep
= netdev_priv(ndev
);
543 struct hwtstamp_config config
;
546 config
.tx_type
= fep
->hwts_tx_en
? HWTSTAMP_TX_ON
: HWTSTAMP_TX_OFF
;
547 config
.rx_filter
= (fep
->hwts_rx_en
?
548 HWTSTAMP_FILTER_ALL
: HWTSTAMP_FILTER_NONE
);
550 return copy_to_user(ifr
->ifr_data
, &config
, sizeof(config
)) ?
555 * fec_time_keep - call timecounter_read every second to avoid timer overrun
556 * because ENET just support 32bit counter, will timeout in 4s
558 static void fec_time_keep(struct work_struct
*work
)
560 struct delayed_work
*dwork
= to_delayed_work(work
);
561 struct fec_enet_private
*fep
= container_of(dwork
, struct fec_enet_private
, time_keep
);
565 mutex_lock(&fep
->ptp_clk_mutex
);
566 if (fep
->ptp_clk_on
) {
567 spin_lock_irqsave(&fep
->tmreg_lock
, flags
);
568 ns
= timecounter_read(&fep
->tc
);
569 spin_unlock_irqrestore(&fep
->tmreg_lock
, flags
);
571 mutex_unlock(&fep
->ptp_clk_mutex
);
573 schedule_delayed_work(&fep
->time_keep
, HZ
);
578 * @ndev: The FEC network adapter
580 * This function performs the required steps for enabling ptp
581 * support. If ptp support has already been loaded it simply calls the
582 * cyclecounter init routine and exits.
585 void fec_ptp_init(struct platform_device
*pdev
)
587 struct net_device
*ndev
= platform_get_drvdata(pdev
);
588 struct fec_enet_private
*fep
= netdev_priv(ndev
);
590 fep
->ptp_caps
.owner
= THIS_MODULE
;
591 snprintf(fep
->ptp_caps
.name
, 16, "fec ptp");
593 fep
->ptp_caps
.max_adj
= 250000000;
594 fep
->ptp_caps
.n_alarm
= 0;
595 fep
->ptp_caps
.n_ext_ts
= 0;
596 fep
->ptp_caps
.n_per_out
= 0;
597 fep
->ptp_caps
.n_pins
= 0;
598 fep
->ptp_caps
.pps
= 1;
599 fep
->ptp_caps
.adjfreq
= fec_ptp_adjfreq
;
600 fep
->ptp_caps
.adjtime
= fec_ptp_adjtime
;
601 fep
->ptp_caps
.gettime
= fec_ptp_gettime
;
602 fep
->ptp_caps
.settime
= fec_ptp_settime
;
603 fep
->ptp_caps
.enable
= fec_ptp_enable
;
605 fep
->cycle_speed
= clk_get_rate(fep
->clk_ptp
);
606 fep
->ptp_inc
= NSEC_PER_SEC
/ fep
->cycle_speed
;
608 spin_lock_init(&fep
->tmreg_lock
);
610 fec_ptp_start_cyclecounter(ndev
);
612 INIT_DELAYED_WORK(&fep
->time_keep
, fec_time_keep
);
614 fep
->ptp_clock
= ptp_clock_register(&fep
->ptp_caps
, &pdev
->dev
);
615 if (IS_ERR(fep
->ptp_clock
)) {
616 fep
->ptp_clock
= NULL
;
617 pr_err("ptp_clock_register failed\n");
620 schedule_delayed_work(&fep
->time_keep
, HZ
);
624 * fec_ptp_check_pps_event
625 * @fep: the fec_enet_private structure handle
627 * This function check the pps event and reload the timer compare counter.
629 uint
fec_ptp_check_pps_event(struct fec_enet_private
*fep
)
632 u8 channel
= fep
->pps_channel
;
633 struct ptp_clock_event event
;
635 val
= readl(fep
->hwp
+ FEC_TCSR(channel
));
636 if (val
& FEC_T_TF_MASK
) {
637 /* Write the next next compare(not the next according the spec)
638 * value to the register
640 writel(fep
->next_counter
, fep
->hwp
+ FEC_TCCR(channel
));
642 writel(val
, fep
->hwp
+ FEC_TCSR(channel
));
643 } while (readl(fep
->hwp
+ FEC_TCSR(channel
)) & FEC_T_TF_MASK
);
645 /* Update the counter; */
646 fep
->next_counter
= (fep
->next_counter
+ fep
->reload_period
) & fep
->cc
.mask
;
648 event
.type
= PTP_CLOCK_PPS
;
649 ptp_clock_event(fep
->ptp_clock
, &event
);