xref: /linux/drivers/ptp/ptp_pch.c (revision 87c9c16317882dd6dbbc07e349bc3223e14f3244)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * PTP 1588 clock using the EG20T PCH
4  *
5  * Copyright (C) 2010 OMICRON electronics GmbH
6  * Copyright (C) 2011-2012 LAPIS SEMICONDUCTOR Co., LTD.
7  *
8  * This code was derived from the IXP46X driver.
9  */
10 
11 #include <linux/device.h>
12 #include <linux/err.h>
13 #include <linux/init.h>
14 #include <linux/interrupt.h>
15 #include <linux/io.h>
16 #include <linux/irq.h>
17 #include <linux/kernel.h>
18 #include <linux/module.h>
19 #include <linux/pci.h>
20 #include <linux/ptp_clock_kernel.h>
21 #include <linux/ptp_pch.h>
22 #include <linux/slab.h>
23 
24 #define STATION_ADDR_LEN	20
25 #define PCI_DEVICE_ID_PCH_1588	0x8819
26 #define IO_MEM_BAR 1
27 
28 #define DEFAULT_ADDEND 0xA0000000
29 #define TICKS_NS_SHIFT  5
30 #define N_EXT_TS	2
31 
32 enum pch_status {
33 	PCH_SUCCESS,
34 	PCH_INVALIDPARAM,
35 	PCH_NOTIMESTAMP,
36 	PCH_INTERRUPTMODEINUSE,
37 	PCH_FAILED,
38 	PCH_UNSUPPORTED,
39 };
40 
41 /*
42  * struct pch_ts_regs - IEEE 1588 registers
43  */
44 struct pch_ts_regs {
45 	u32 control;
46 	u32 event;
47 	u32 addend;
48 	u32 accum;
49 	u32 test;
50 	u32 ts_compare;
51 	u32 rsystime_lo;
52 	u32 rsystime_hi;
53 	u32 systime_lo;
54 	u32 systime_hi;
55 	u32 trgt_lo;
56 	u32 trgt_hi;
57 	u32 asms_lo;
58 	u32 asms_hi;
59 	u32 amms_lo;
60 	u32 amms_hi;
61 	u32 ch_control;
62 	u32 ch_event;
63 	u32 tx_snap_lo;
64 	u32 tx_snap_hi;
65 	u32 rx_snap_lo;
66 	u32 rx_snap_hi;
67 	u32 src_uuid_lo;
68 	u32 src_uuid_hi;
69 	u32 can_status;
70 	u32 can_snap_lo;
71 	u32 can_snap_hi;
72 	u32 ts_sel;
73 	u32 ts_st[6];
74 	u32 reserve1[14];
75 	u32 stl_max_set_en;
76 	u32 stl_max_set;
77 	u32 reserve2[13];
78 	u32 srst;
79 };
80 
81 #define PCH_TSC_RESET		(1 << 0)
82 #define PCH_TSC_TTM_MASK	(1 << 1)
83 #define PCH_TSC_ASMS_MASK	(1 << 2)
84 #define PCH_TSC_AMMS_MASK	(1 << 3)
85 #define PCH_TSC_PPSM_MASK	(1 << 4)
86 #define PCH_TSE_TTIPEND		(1 << 1)
87 #define PCH_TSE_SNS		(1 << 2)
88 #define PCH_TSE_SNM		(1 << 3)
89 #define PCH_TSE_PPS		(1 << 4)
90 #define PCH_CC_MM		(1 << 0)
91 #define PCH_CC_TA		(1 << 1)
92 
93 #define PCH_CC_MODE_SHIFT	16
94 #define PCH_CC_MODE_MASK	0x001F0000
95 #define PCH_CC_VERSION		(1 << 31)
96 #define PCH_CE_TXS		(1 << 0)
97 #define PCH_CE_RXS		(1 << 1)
98 #define PCH_CE_OVR		(1 << 0)
99 #define PCH_CE_VAL		(1 << 1)
100 #define PCH_ECS_ETH		(1 << 0)
101 
102 #define PCH_ECS_CAN		(1 << 1)
103 #define PCH_STATION_BYTES	6
104 
105 #define PCH_IEEE1588_ETH	(1 << 0)
106 #define PCH_IEEE1588_CAN	(1 << 1)
107 
108 /*
109  * struct pch_dev - Driver private data
110  */
111 struct pch_dev {
112 	struct pch_ts_regs __iomem *regs;
113 	struct ptp_clock *ptp_clock;
114 	struct ptp_clock_info caps;
115 	int exts0_enabled;
116 	int exts1_enabled;
117 
118 	u32 mem_base;
119 	u32 mem_size;
120 	u32 irq;
121 	struct pci_dev *pdev;
122 	spinlock_t register_lock;
123 };
124 
125 /*
126  * struct pch_params - 1588 module parameter
127  */
128 struct pch_params {
129 	u8 station[STATION_ADDR_LEN];
130 };
131 
132 /* structure to hold the module parameters */
133 static struct pch_params pch_param = {
134 	"00:00:00:00:00:00"
135 };
136 
137 /*
138  * Register access functions
139  */
140 static inline void pch_eth_enable_set(struct pch_dev *chip)
141 {
142 	u32 val;
143 	/* SET the eth_enable bit */
144 	val = ioread32(&chip->regs->ts_sel) | (PCH_ECS_ETH);
145 	iowrite32(val, (&chip->regs->ts_sel));
146 }
147 
148 static u64 pch_systime_read(struct pch_ts_regs __iomem *regs)
149 {
150 	u64 ns;
151 	u32 lo, hi;
152 
153 	lo = ioread32(&regs->systime_lo);
154 	hi = ioread32(&regs->systime_hi);
155 
156 	ns = ((u64) hi) << 32;
157 	ns |= lo;
158 	ns <<= TICKS_NS_SHIFT;
159 
160 	return ns;
161 }
162 
163 static void pch_systime_write(struct pch_ts_regs __iomem *regs, u64 ns)
164 {
165 	u32 hi, lo;
166 
167 	ns >>= TICKS_NS_SHIFT;
168 	hi = ns >> 32;
169 	lo = ns & 0xffffffff;
170 
171 	iowrite32(lo, &regs->systime_lo);
172 	iowrite32(hi, &regs->systime_hi);
173 }
174 
175 static inline void pch_block_reset(struct pch_dev *chip)
176 {
177 	u32 val;
178 	/* Reset Hardware Assist block */
179 	val = ioread32(&chip->regs->control) | PCH_TSC_RESET;
180 	iowrite32(val, (&chip->regs->control));
181 	val = val & ~PCH_TSC_RESET;
182 	iowrite32(val, (&chip->regs->control));
183 }
184 
185 void pch_ch_control_write(struct pci_dev *pdev, u32 val)
186 {
187 	struct pch_dev *chip = pci_get_drvdata(pdev);
188 
189 	iowrite32(val, (&chip->regs->ch_control));
190 }
191 EXPORT_SYMBOL(pch_ch_control_write);
192 
193 u32 pch_ch_event_read(struct pci_dev *pdev)
194 {
195 	struct pch_dev *chip = pci_get_drvdata(pdev);
196 	u32 val;
197 
198 	val = ioread32(&chip->regs->ch_event);
199 
200 	return val;
201 }
202 EXPORT_SYMBOL(pch_ch_event_read);
203 
204 void pch_ch_event_write(struct pci_dev *pdev, u32 val)
205 {
206 	struct pch_dev *chip = pci_get_drvdata(pdev);
207 
208 	iowrite32(val, (&chip->regs->ch_event));
209 }
210 EXPORT_SYMBOL(pch_ch_event_write);
211 
212 u32 pch_src_uuid_lo_read(struct pci_dev *pdev)
213 {
214 	struct pch_dev *chip = pci_get_drvdata(pdev);
215 	u32 val;
216 
217 	val = ioread32(&chip->regs->src_uuid_lo);
218 
219 	return val;
220 }
221 EXPORT_SYMBOL(pch_src_uuid_lo_read);
222 
223 u32 pch_src_uuid_hi_read(struct pci_dev *pdev)
224 {
225 	struct pch_dev *chip = pci_get_drvdata(pdev);
226 	u32 val;
227 
228 	val = ioread32(&chip->regs->src_uuid_hi);
229 
230 	return val;
231 }
232 EXPORT_SYMBOL(pch_src_uuid_hi_read);
233 
234 u64 pch_rx_snap_read(struct pci_dev *pdev)
235 {
236 	struct pch_dev *chip = pci_get_drvdata(pdev);
237 	u64 ns;
238 	u32 lo, hi;
239 
240 	lo = ioread32(&chip->regs->rx_snap_lo);
241 	hi = ioread32(&chip->regs->rx_snap_hi);
242 
243 	ns = ((u64) hi) << 32;
244 	ns |= lo;
245 	ns <<= TICKS_NS_SHIFT;
246 
247 	return ns;
248 }
249 EXPORT_SYMBOL(pch_rx_snap_read);
250 
251 u64 pch_tx_snap_read(struct pci_dev *pdev)
252 {
253 	struct pch_dev *chip = pci_get_drvdata(pdev);
254 	u64 ns;
255 	u32 lo, hi;
256 
257 	lo = ioread32(&chip->regs->tx_snap_lo);
258 	hi = ioread32(&chip->regs->tx_snap_hi);
259 
260 	ns = ((u64) hi) << 32;
261 	ns |= lo;
262 	ns <<= TICKS_NS_SHIFT;
263 
264 	return ns;
265 }
266 EXPORT_SYMBOL(pch_tx_snap_read);
267 
268 /* This function enables all 64 bits in system time registers [high & low].
269 This is a work-around for non continuous value in the SystemTime Register*/
270 static void pch_set_system_time_count(struct pch_dev *chip)
271 {
272 	iowrite32(0x01, &chip->regs->stl_max_set_en);
273 	iowrite32(0xFFFFFFFF, &chip->regs->stl_max_set);
274 	iowrite32(0x00, &chip->regs->stl_max_set_en);
275 }
276 
277 static void pch_reset(struct pch_dev *chip)
278 {
279 	/* Reset Hardware Assist */
280 	pch_block_reset(chip);
281 
282 	/* enable all 32 bits in system time registers */
283 	pch_set_system_time_count(chip);
284 }
285 
286 /**
287  * pch_set_station_address() - This API sets the station address used by
288  *				    IEEE 1588 hardware when looking at PTP
289  *				    traffic on the  ethernet interface
290  * @addr:	dress which contain the column separated address to be used.
291  * @pdev:	PCI device.
292  */
293 int pch_set_station_address(u8 *addr, struct pci_dev *pdev)
294 {
295 	s32 i;
296 	struct pch_dev *chip = pci_get_drvdata(pdev);
297 
298 	/* Verify the parameter */
299 	if ((chip->regs == NULL) || addr == (u8 *)NULL) {
300 		dev_err(&pdev->dev,
301 			"invalid params returning PCH_INVALIDPARAM\n");
302 		return PCH_INVALIDPARAM;
303 	}
304 	/* For all station address bytes */
305 	for (i = 0; i < PCH_STATION_BYTES; i++) {
306 		u32 val;
307 		s32 tmp;
308 
309 		tmp = hex_to_bin(addr[i * 3]);
310 		if (tmp < 0) {
311 			dev_err(&pdev->dev,
312 				"invalid params returning PCH_INVALIDPARAM\n");
313 			return PCH_INVALIDPARAM;
314 		}
315 		val = tmp * 16;
316 		tmp = hex_to_bin(addr[(i * 3) + 1]);
317 		if (tmp < 0) {
318 			dev_err(&pdev->dev,
319 				"invalid params returning PCH_INVALIDPARAM\n");
320 			return PCH_INVALIDPARAM;
321 		}
322 		val += tmp;
323 		/* Expects ':' separated addresses */
324 		if ((i < 5) && (addr[(i * 3) + 2] != ':')) {
325 			dev_err(&pdev->dev,
326 				"invalid params returning PCH_INVALIDPARAM\n");
327 			return PCH_INVALIDPARAM;
328 		}
329 
330 		/* Ideally we should set the address only after validating
331 							 entire string */
332 		dev_dbg(&pdev->dev, "invoking pch_station_set\n");
333 		iowrite32(val, &chip->regs->ts_st[i]);
334 	}
335 	return 0;
336 }
337 EXPORT_SYMBOL(pch_set_station_address);
338 
339 /*
340  * Interrupt service routine
341  */
342 static irqreturn_t isr(int irq, void *priv)
343 {
344 	struct pch_dev *pch_dev = priv;
345 	struct pch_ts_regs __iomem *regs = pch_dev->regs;
346 	struct ptp_clock_event event;
347 	u32 ack = 0, lo, hi, val;
348 
349 	val = ioread32(&regs->event);
350 
351 	if (val & PCH_TSE_SNS) {
352 		ack |= PCH_TSE_SNS;
353 		if (pch_dev->exts0_enabled) {
354 			hi = ioread32(&regs->asms_hi);
355 			lo = ioread32(&regs->asms_lo);
356 			event.type = PTP_CLOCK_EXTTS;
357 			event.index = 0;
358 			event.timestamp = ((u64) hi) << 32;
359 			event.timestamp |= lo;
360 			event.timestamp <<= TICKS_NS_SHIFT;
361 			ptp_clock_event(pch_dev->ptp_clock, &event);
362 		}
363 	}
364 
365 	if (val & PCH_TSE_SNM) {
366 		ack |= PCH_TSE_SNM;
367 		if (pch_dev->exts1_enabled) {
368 			hi = ioread32(&regs->amms_hi);
369 			lo = ioread32(&regs->amms_lo);
370 			event.type = PTP_CLOCK_EXTTS;
371 			event.index = 1;
372 			event.timestamp = ((u64) hi) << 32;
373 			event.timestamp |= lo;
374 			event.timestamp <<= TICKS_NS_SHIFT;
375 			ptp_clock_event(pch_dev->ptp_clock, &event);
376 		}
377 	}
378 
379 	if (val & PCH_TSE_TTIPEND)
380 		ack |= PCH_TSE_TTIPEND; /* this bit seems to be always set */
381 
382 	if (ack) {
383 		iowrite32(ack, &regs->event);
384 		return IRQ_HANDLED;
385 	} else
386 		return IRQ_NONE;
387 }
388 
389 /*
390  * PTP clock operations
391  */
392 
393 static int ptp_pch_adjfreq(struct ptp_clock_info *ptp, s32 ppb)
394 {
395 	u64 adj;
396 	u32 diff, addend;
397 	int neg_adj = 0;
398 	struct pch_dev *pch_dev = container_of(ptp, struct pch_dev, caps);
399 	struct pch_ts_regs __iomem *regs = pch_dev->regs;
400 
401 	if (ppb < 0) {
402 		neg_adj = 1;
403 		ppb = -ppb;
404 	}
405 	addend = DEFAULT_ADDEND;
406 	adj = addend;
407 	adj *= ppb;
408 	diff = div_u64(adj, 1000000000ULL);
409 
410 	addend = neg_adj ? addend - diff : addend + diff;
411 
412 	iowrite32(addend, &regs->addend);
413 
414 	return 0;
415 }
416 
417 static int ptp_pch_adjtime(struct ptp_clock_info *ptp, s64 delta)
418 {
419 	s64 now;
420 	unsigned long flags;
421 	struct pch_dev *pch_dev = container_of(ptp, struct pch_dev, caps);
422 	struct pch_ts_regs __iomem *regs = pch_dev->regs;
423 
424 	spin_lock_irqsave(&pch_dev->register_lock, flags);
425 	now = pch_systime_read(regs);
426 	now += delta;
427 	pch_systime_write(regs, now);
428 	spin_unlock_irqrestore(&pch_dev->register_lock, flags);
429 
430 	return 0;
431 }
432 
433 static int ptp_pch_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
434 {
435 	u64 ns;
436 	unsigned long flags;
437 	struct pch_dev *pch_dev = container_of(ptp, struct pch_dev, caps);
438 	struct pch_ts_regs __iomem *regs = pch_dev->regs;
439 
440 	spin_lock_irqsave(&pch_dev->register_lock, flags);
441 	ns = pch_systime_read(regs);
442 	spin_unlock_irqrestore(&pch_dev->register_lock, flags);
443 
444 	*ts = ns_to_timespec64(ns);
445 	return 0;
446 }
447 
448 static int ptp_pch_settime(struct ptp_clock_info *ptp,
449 			   const struct timespec64 *ts)
450 {
451 	u64 ns;
452 	unsigned long flags;
453 	struct pch_dev *pch_dev = container_of(ptp, struct pch_dev, caps);
454 	struct pch_ts_regs __iomem *regs = pch_dev->regs;
455 
456 	ns = timespec64_to_ns(ts);
457 
458 	spin_lock_irqsave(&pch_dev->register_lock, flags);
459 	pch_systime_write(regs, ns);
460 	spin_unlock_irqrestore(&pch_dev->register_lock, flags);
461 
462 	return 0;
463 }
464 
465 static int ptp_pch_enable(struct ptp_clock_info *ptp,
466 			  struct ptp_clock_request *rq, int on)
467 {
468 	struct pch_dev *pch_dev = container_of(ptp, struct pch_dev, caps);
469 
470 	switch (rq->type) {
471 	case PTP_CLK_REQ_EXTTS:
472 		switch (rq->extts.index) {
473 		case 0:
474 			pch_dev->exts0_enabled = on ? 1 : 0;
475 			break;
476 		case 1:
477 			pch_dev->exts1_enabled = on ? 1 : 0;
478 			break;
479 		default:
480 			return -EINVAL;
481 		}
482 		return 0;
483 	default:
484 		break;
485 	}
486 
487 	return -EOPNOTSUPP;
488 }
489 
490 static const struct ptp_clock_info ptp_pch_caps = {
491 	.owner		= THIS_MODULE,
492 	.name		= "PCH timer",
493 	.max_adj	= 50000000,
494 	.n_ext_ts	= N_EXT_TS,
495 	.n_pins		= 0,
496 	.pps		= 0,
497 	.adjfreq	= ptp_pch_adjfreq,
498 	.adjtime	= ptp_pch_adjtime,
499 	.gettime64	= ptp_pch_gettime,
500 	.settime64	= ptp_pch_settime,
501 	.enable		= ptp_pch_enable,
502 };
503 
504 #define pch_suspend NULL
505 #define pch_resume NULL
506 
507 static void pch_remove(struct pci_dev *pdev)
508 {
509 	struct pch_dev *chip = pci_get_drvdata(pdev);
510 
511 	ptp_clock_unregister(chip->ptp_clock);
512 	/* free the interrupt */
513 	if (pdev->irq != 0)
514 		free_irq(pdev->irq, chip);
515 
516 	/* unmap the virtual IO memory space */
517 	if (chip->regs != NULL) {
518 		iounmap(chip->regs);
519 		chip->regs = NULL;
520 	}
521 	/* release the reserved IO memory space */
522 	if (chip->mem_base != 0) {
523 		release_mem_region(chip->mem_base, chip->mem_size);
524 		chip->mem_base = 0;
525 	}
526 	pci_disable_device(pdev);
527 	kfree(chip);
528 	dev_info(&pdev->dev, "complete\n");
529 }
530 
531 static s32
532 pch_probe(struct pci_dev *pdev, const struct pci_device_id *id)
533 {
534 	s32 ret;
535 	unsigned long flags;
536 	struct pch_dev *chip;
537 
538 	chip = kzalloc(sizeof(struct pch_dev), GFP_KERNEL);
539 	if (chip == NULL)
540 		return -ENOMEM;
541 
542 	/* enable the 1588 pci device */
543 	ret = pci_enable_device(pdev);
544 	if (ret != 0) {
545 		dev_err(&pdev->dev, "could not enable the pci device\n");
546 		goto err_pci_en;
547 	}
548 
549 	chip->mem_base = pci_resource_start(pdev, IO_MEM_BAR);
550 	if (!chip->mem_base) {
551 		dev_err(&pdev->dev, "could not locate IO memory address\n");
552 		ret = -ENODEV;
553 		goto err_pci_start;
554 	}
555 
556 	/* retrieve the available length of the IO memory space */
557 	chip->mem_size = pci_resource_len(pdev, IO_MEM_BAR);
558 
559 	/* allocate the memory for the device registers */
560 	if (!request_mem_region(chip->mem_base, chip->mem_size, "1588_regs")) {
561 		dev_err(&pdev->dev,
562 			"could not allocate register memory space\n");
563 		ret = -EBUSY;
564 		goto err_req_mem_region;
565 	}
566 
567 	/* get the virtual address to the 1588 registers */
568 	chip->regs = ioremap(chip->mem_base, chip->mem_size);
569 
570 	if (!chip->regs) {
571 		dev_err(&pdev->dev, "Could not get virtual address\n");
572 		ret = -ENOMEM;
573 		goto err_ioremap;
574 	}
575 
576 	chip->caps = ptp_pch_caps;
577 	chip->ptp_clock = ptp_clock_register(&chip->caps, &pdev->dev);
578 	if (IS_ERR(chip->ptp_clock)) {
579 		ret = PTR_ERR(chip->ptp_clock);
580 		goto err_ptp_clock_reg;
581 	}
582 
583 	spin_lock_init(&chip->register_lock);
584 
585 	ret = request_irq(pdev->irq, &isr, IRQF_SHARED, KBUILD_MODNAME, chip);
586 	if (ret != 0) {
587 		dev_err(&pdev->dev, "failed to get irq %d\n", pdev->irq);
588 		goto err_req_irq;
589 	}
590 
591 	/* indicate success */
592 	chip->irq = pdev->irq;
593 	chip->pdev = pdev;
594 	pci_set_drvdata(pdev, chip);
595 
596 	spin_lock_irqsave(&chip->register_lock, flags);
597 	/* reset the ieee1588 h/w */
598 	pch_reset(chip);
599 
600 	iowrite32(DEFAULT_ADDEND, &chip->regs->addend);
601 	iowrite32(1, &chip->regs->trgt_lo);
602 	iowrite32(0, &chip->regs->trgt_hi);
603 	iowrite32(PCH_TSE_TTIPEND, &chip->regs->event);
604 
605 	pch_eth_enable_set(chip);
606 
607 	if (strcmp(pch_param.station, "00:00:00:00:00:00") != 0) {
608 		if (pch_set_station_address(pch_param.station, pdev) != 0) {
609 			dev_err(&pdev->dev,
610 			"Invalid station address parameter\n"
611 			"Module loaded but station address not set correctly\n"
612 			);
613 		}
614 	}
615 	spin_unlock_irqrestore(&chip->register_lock, flags);
616 	return 0;
617 
618 err_req_irq:
619 	ptp_clock_unregister(chip->ptp_clock);
620 err_ptp_clock_reg:
621 	iounmap(chip->regs);
622 	chip->regs = NULL;
623 
624 err_ioremap:
625 	release_mem_region(chip->mem_base, chip->mem_size);
626 
627 err_req_mem_region:
628 	chip->mem_base = 0;
629 
630 err_pci_start:
631 	pci_disable_device(pdev);
632 
633 err_pci_en:
634 	kfree(chip);
635 	dev_err(&pdev->dev, "probe failed(ret=0x%x)\n", ret);
636 
637 	return ret;
638 }
639 
640 static const struct pci_device_id pch_ieee1588_pcidev_id[] = {
641 	{
642 	  .vendor = PCI_VENDOR_ID_INTEL,
643 	  .device = PCI_DEVICE_ID_PCH_1588
644 	 },
645 	{0}
646 };
647 
648 static SIMPLE_DEV_PM_OPS(pch_pm_ops, pch_suspend, pch_resume);
649 
650 static struct pci_driver pch_driver = {
651 	.name = KBUILD_MODNAME,
652 	.id_table = pch_ieee1588_pcidev_id,
653 	.probe = pch_probe,
654 	.remove = pch_remove,
655 	.driver.pm = &pch_pm_ops,
656 };
657 
658 static void __exit ptp_pch_exit(void)
659 {
660 	pci_unregister_driver(&pch_driver);
661 }
662 
663 static s32 __init ptp_pch_init(void)
664 {
665 	s32 ret;
666 
667 	/* register the driver with the pci core */
668 	ret = pci_register_driver(&pch_driver);
669 
670 	return ret;
671 }
672 
673 module_init(ptp_pch_init);
674 module_exit(ptp_pch_exit);
675 
676 module_param_string(station,
677 		    pch_param.station, sizeof(pch_param.station), 0444);
678 MODULE_PARM_DESC(station,
679 	 "IEEE 1588 station address to use - colon separated hex values");
680 
681 MODULE_AUTHOR("LAPIS SEMICONDUCTOR, <tshimizu818@gmail.com>");
682 MODULE_DESCRIPTION("PTP clock using the EG20T timer");
683 MODULE_LICENSE("GPL");
684