xref: /openbmc/linux/drivers/ptp/ptp_pch.c (revision c4e78957)
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/interrupt.h>
14 #include <linux/io.h>
15 #include <linux/io-64-nonatomic-lo-hi.h>
16 #include <linux/io-64-nonatomic-hi-lo.h>
17 #include <linux/irq.h>
18 #include <linux/kernel.h>
19 #include <linux/module.h>
20 #include <linux/pci.h>
21 #include <linux/ptp_clock_kernel.h>
22 #include <linux/ptp_pch.h>
23 #include <linux/slab.h>
24 
25 #define STATION_ADDR_LEN	20
26 #define PCI_DEVICE_ID_PCH_1588	0x8819
27 #define IO_MEM_BAR 1
28 
29 #define DEFAULT_ADDEND 0xA0000000
30 #define TICKS_NS_SHIFT  5
31 #define N_EXT_TS	2
32 
33 enum pch_status {
34 	PCH_SUCCESS,
35 	PCH_INVALIDPARAM,
36 	PCH_NOTIMESTAMP,
37 	PCH_INTERRUPTMODEINUSE,
38 	PCH_FAILED,
39 	PCH_UNSUPPORTED,
40 };
41 
42 /*
43  * struct pch_ts_regs - IEEE 1588 registers
44  */
45 struct pch_ts_regs {
46 	u32 control;
47 	u32 event;
48 	u32 addend;
49 	u32 accum;
50 	u32 test;
51 	u32 ts_compare;
52 	u32 rsystime_lo;
53 	u32 rsystime_hi;
54 	u32 systime_lo;
55 	u32 systime_hi;
56 	u32 trgt_lo;
57 	u32 trgt_hi;
58 	u32 asms_lo;
59 	u32 asms_hi;
60 	u32 amms_lo;
61 	u32 amms_hi;
62 	u32 ch_control;
63 	u32 ch_event;
64 	u32 tx_snap_lo;
65 	u32 tx_snap_hi;
66 	u32 rx_snap_lo;
67 	u32 rx_snap_hi;
68 	u32 src_uuid_lo;
69 	u32 src_uuid_hi;
70 	u32 can_status;
71 	u32 can_snap_lo;
72 	u32 can_snap_hi;
73 	u32 ts_sel;
74 	u32 ts_st[6];
75 	u32 reserve1[14];
76 	u32 stl_max_set_en;
77 	u32 stl_max_set;
78 	u32 reserve2[13];
79 	u32 srst;
80 };
81 
82 #define PCH_TSC_RESET		(1 << 0)
83 #define PCH_TSC_TTM_MASK	(1 << 1)
84 #define PCH_TSC_ASMS_MASK	(1 << 2)
85 #define PCH_TSC_AMMS_MASK	(1 << 3)
86 #define PCH_TSC_PPSM_MASK	(1 << 4)
87 #define PCH_TSE_TTIPEND		(1 << 1)
88 #define PCH_TSE_SNS		(1 << 2)
89 #define PCH_TSE_SNM		(1 << 3)
90 #define PCH_TSE_PPS		(1 << 4)
91 #define PCH_CC_MM		(1 << 0)
92 #define PCH_CC_TA		(1 << 1)
93 
94 #define PCH_CC_MODE_SHIFT	16
95 #define PCH_CC_MODE_MASK	0x001F0000
96 #define PCH_CC_VERSION		(1 << 31)
97 #define PCH_CE_TXS		(1 << 0)
98 #define PCH_CE_RXS		(1 << 1)
99 #define PCH_CE_OVR		(1 << 0)
100 #define PCH_CE_VAL		(1 << 1)
101 #define PCH_ECS_ETH		(1 << 0)
102 
103 #define PCH_ECS_CAN		(1 << 1)
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 irq;
119 	struct pci_dev *pdev;
120 	spinlock_t register_lock;
121 };
122 
123 /*
124  * struct pch_params - 1588 module parameter
125  */
126 struct pch_params {
127 	u8 station[STATION_ADDR_LEN];
128 };
129 
130 /* structure to hold the module parameters */
131 static struct pch_params pch_param = {
132 	"00:00:00:00:00:00"
133 };
134 
135 /*
136  * Register access functions
137  */
138 static inline void pch_eth_enable_set(struct pch_dev *chip)
139 {
140 	u32 val;
141 	/* SET the eth_enable bit */
142 	val = ioread32(&chip->regs->ts_sel) | (PCH_ECS_ETH);
143 	iowrite32(val, (&chip->regs->ts_sel));
144 }
145 
146 static u64 pch_systime_read(struct pch_ts_regs __iomem *regs)
147 {
148 	u64 ns;
149 
150 	ns = ioread64_lo_hi(&regs->systime_lo);
151 
152 	return ns << TICKS_NS_SHIFT;
153 }
154 
155 static void pch_systime_write(struct pch_ts_regs __iomem *regs, u64 ns)
156 {
157 	iowrite64_lo_hi(ns >> TICKS_NS_SHIFT, &regs->systime_lo);
158 }
159 
160 static inline void pch_block_reset(struct pch_dev *chip)
161 {
162 	u32 val;
163 	/* Reset Hardware Assist block */
164 	val = ioread32(&chip->regs->control) | PCH_TSC_RESET;
165 	iowrite32(val, (&chip->regs->control));
166 	val = val & ~PCH_TSC_RESET;
167 	iowrite32(val, (&chip->regs->control));
168 }
169 
170 void pch_ch_control_write(struct pci_dev *pdev, u32 val)
171 {
172 	struct pch_dev *chip = pci_get_drvdata(pdev);
173 
174 	iowrite32(val, (&chip->regs->ch_control));
175 }
176 EXPORT_SYMBOL(pch_ch_control_write);
177 
178 u32 pch_ch_event_read(struct pci_dev *pdev)
179 {
180 	struct pch_dev *chip = pci_get_drvdata(pdev);
181 	u32 val;
182 
183 	val = ioread32(&chip->regs->ch_event);
184 
185 	return val;
186 }
187 EXPORT_SYMBOL(pch_ch_event_read);
188 
189 void pch_ch_event_write(struct pci_dev *pdev, u32 val)
190 {
191 	struct pch_dev *chip = pci_get_drvdata(pdev);
192 
193 	iowrite32(val, (&chip->regs->ch_event));
194 }
195 EXPORT_SYMBOL(pch_ch_event_write);
196 
197 u32 pch_src_uuid_lo_read(struct pci_dev *pdev)
198 {
199 	struct pch_dev *chip = pci_get_drvdata(pdev);
200 	u32 val;
201 
202 	val = ioread32(&chip->regs->src_uuid_lo);
203 
204 	return val;
205 }
206 EXPORT_SYMBOL(pch_src_uuid_lo_read);
207 
208 u32 pch_src_uuid_hi_read(struct pci_dev *pdev)
209 {
210 	struct pch_dev *chip = pci_get_drvdata(pdev);
211 	u32 val;
212 
213 	val = ioread32(&chip->regs->src_uuid_hi);
214 
215 	return val;
216 }
217 EXPORT_SYMBOL(pch_src_uuid_hi_read);
218 
219 u64 pch_rx_snap_read(struct pci_dev *pdev)
220 {
221 	struct pch_dev *chip = pci_get_drvdata(pdev);
222 	u64 ns;
223 
224 	ns = ioread64_lo_hi(&chip->regs->rx_snap_lo);
225 
226 	return ns << TICKS_NS_SHIFT;
227 }
228 EXPORT_SYMBOL(pch_rx_snap_read);
229 
230 u64 pch_tx_snap_read(struct pci_dev *pdev)
231 {
232 	struct pch_dev *chip = pci_get_drvdata(pdev);
233 	u64 ns;
234 
235 	ns = ioread64_lo_hi(&chip->regs->tx_snap_lo);
236 
237 	return ns << TICKS_NS_SHIFT;
238 }
239 EXPORT_SYMBOL(pch_tx_snap_read);
240 
241 /* This function enables all 64 bits in system time registers [high & low].
242 This is a work-around for non continuous value in the SystemTime Register*/
243 static void pch_set_system_time_count(struct pch_dev *chip)
244 {
245 	iowrite32(0x01, &chip->regs->stl_max_set_en);
246 	iowrite32(0xFFFFFFFF, &chip->regs->stl_max_set);
247 	iowrite32(0x00, &chip->regs->stl_max_set_en);
248 }
249 
250 static void pch_reset(struct pch_dev *chip)
251 {
252 	/* Reset Hardware Assist */
253 	pch_block_reset(chip);
254 
255 	/* enable all 32 bits in system time registers */
256 	pch_set_system_time_count(chip);
257 }
258 
259 /**
260  * pch_set_station_address() - This API sets the station address used by
261  *				    IEEE 1588 hardware when looking at PTP
262  *				    traffic on the  ethernet interface
263  * @addr:	dress which contain the column separated address to be used.
264  * @pdev:	PCI device.
265  */
266 int pch_set_station_address(u8 *addr, struct pci_dev *pdev)
267 {
268 	struct pch_dev *chip = pci_get_drvdata(pdev);
269 	bool valid;
270 	u64 mac;
271 
272 	/* Verify the parameter */
273 	if ((chip->regs == NULL) || addr == (u8 *)NULL) {
274 		dev_err(&pdev->dev,
275 			"invalid params returning PCH_INVALIDPARAM\n");
276 		return PCH_INVALIDPARAM;
277 	}
278 
279 	valid = mac_pton(addr, (u8 *)&mac);
280 	if (!valid) {
281 		dev_err(&pdev->dev, "invalid params returning PCH_INVALIDPARAM\n");
282 		return PCH_INVALIDPARAM;
283 	}
284 
285 	dev_dbg(&pdev->dev, "invoking pch_station_set\n");
286 	iowrite64_lo_hi(mac, &chip->regs->ts_st);
287 	return 0;
288 }
289 EXPORT_SYMBOL(pch_set_station_address);
290 
291 /*
292  * Interrupt service routine
293  */
294 static irqreturn_t isr(int irq, void *priv)
295 {
296 	struct pch_dev *pch_dev = priv;
297 	struct pch_ts_regs __iomem *regs = pch_dev->regs;
298 	struct ptp_clock_event event;
299 	u32 ack = 0, val;
300 
301 	val = ioread32(&regs->event);
302 
303 	if (val & PCH_TSE_SNS) {
304 		ack |= PCH_TSE_SNS;
305 		if (pch_dev->exts0_enabled) {
306 			event.type = PTP_CLOCK_EXTTS;
307 			event.index = 0;
308 			event.timestamp = ioread64_hi_lo(&regs->asms_hi);
309 			event.timestamp <<= TICKS_NS_SHIFT;
310 			ptp_clock_event(pch_dev->ptp_clock, &event);
311 		}
312 	}
313 
314 	if (val & PCH_TSE_SNM) {
315 		ack |= PCH_TSE_SNM;
316 		if (pch_dev->exts1_enabled) {
317 			event.type = PTP_CLOCK_EXTTS;
318 			event.index = 1;
319 			event.timestamp = ioread64_hi_lo(&regs->asms_hi);
320 			event.timestamp <<= TICKS_NS_SHIFT;
321 			ptp_clock_event(pch_dev->ptp_clock, &event);
322 		}
323 	}
324 
325 	if (val & PCH_TSE_TTIPEND)
326 		ack |= PCH_TSE_TTIPEND; /* this bit seems to be always set */
327 
328 	if (ack) {
329 		iowrite32(ack, &regs->event);
330 		return IRQ_HANDLED;
331 	} else
332 		return IRQ_NONE;
333 }
334 
335 /*
336  * PTP clock operations
337  */
338 
339 static int ptp_pch_adjfreq(struct ptp_clock_info *ptp, s32 ppb)
340 {
341 	u64 adj;
342 	u32 diff, addend;
343 	int neg_adj = 0;
344 	struct pch_dev *pch_dev = container_of(ptp, struct pch_dev, caps);
345 	struct pch_ts_regs __iomem *regs = pch_dev->regs;
346 
347 	if (ppb < 0) {
348 		neg_adj = 1;
349 		ppb = -ppb;
350 	}
351 	addend = DEFAULT_ADDEND;
352 	adj = addend;
353 	adj *= ppb;
354 	diff = div_u64(adj, 1000000000ULL);
355 
356 	addend = neg_adj ? addend - diff : addend + diff;
357 
358 	iowrite32(addend, &regs->addend);
359 
360 	return 0;
361 }
362 
363 static int ptp_pch_adjtime(struct ptp_clock_info *ptp, s64 delta)
364 {
365 	s64 now;
366 	unsigned long flags;
367 	struct pch_dev *pch_dev = container_of(ptp, struct pch_dev, caps);
368 	struct pch_ts_regs __iomem *regs = pch_dev->regs;
369 
370 	spin_lock_irqsave(&pch_dev->register_lock, flags);
371 	now = pch_systime_read(regs);
372 	now += delta;
373 	pch_systime_write(regs, now);
374 	spin_unlock_irqrestore(&pch_dev->register_lock, flags);
375 
376 	return 0;
377 }
378 
379 static int ptp_pch_gettime(struct ptp_clock_info *ptp, struct timespec64 *ts)
380 {
381 	u64 ns;
382 	unsigned long flags;
383 	struct pch_dev *pch_dev = container_of(ptp, struct pch_dev, caps);
384 	struct pch_ts_regs __iomem *regs = pch_dev->regs;
385 
386 	spin_lock_irqsave(&pch_dev->register_lock, flags);
387 	ns = pch_systime_read(regs);
388 	spin_unlock_irqrestore(&pch_dev->register_lock, flags);
389 
390 	*ts = ns_to_timespec64(ns);
391 	return 0;
392 }
393 
394 static int ptp_pch_settime(struct ptp_clock_info *ptp,
395 			   const struct timespec64 *ts)
396 {
397 	u64 ns;
398 	unsigned long flags;
399 	struct pch_dev *pch_dev = container_of(ptp, struct pch_dev, caps);
400 	struct pch_ts_regs __iomem *regs = pch_dev->regs;
401 
402 	ns = timespec64_to_ns(ts);
403 
404 	spin_lock_irqsave(&pch_dev->register_lock, flags);
405 	pch_systime_write(regs, ns);
406 	spin_unlock_irqrestore(&pch_dev->register_lock, flags);
407 
408 	return 0;
409 }
410 
411 static int ptp_pch_enable(struct ptp_clock_info *ptp,
412 			  struct ptp_clock_request *rq, int on)
413 {
414 	struct pch_dev *pch_dev = container_of(ptp, struct pch_dev, caps);
415 
416 	switch (rq->type) {
417 	case PTP_CLK_REQ_EXTTS:
418 		switch (rq->extts.index) {
419 		case 0:
420 			pch_dev->exts0_enabled = on ? 1 : 0;
421 			break;
422 		case 1:
423 			pch_dev->exts1_enabled = on ? 1 : 0;
424 			break;
425 		default:
426 			return -EINVAL;
427 		}
428 		return 0;
429 	default:
430 		break;
431 	}
432 
433 	return -EOPNOTSUPP;
434 }
435 
436 static const struct ptp_clock_info ptp_pch_caps = {
437 	.owner		= THIS_MODULE,
438 	.name		= "PCH timer",
439 	.max_adj	= 50000000,
440 	.n_ext_ts	= N_EXT_TS,
441 	.n_pins		= 0,
442 	.pps		= 0,
443 	.adjfreq	= ptp_pch_adjfreq,
444 	.adjtime	= ptp_pch_adjtime,
445 	.gettime64	= ptp_pch_gettime,
446 	.settime64	= ptp_pch_settime,
447 	.enable		= ptp_pch_enable,
448 };
449 
450 static void pch_remove(struct pci_dev *pdev)
451 {
452 	struct pch_dev *chip = pci_get_drvdata(pdev);
453 
454 	free_irq(pdev->irq, chip);
455 	ptp_clock_unregister(chip->ptp_clock);
456 }
457 
458 static s32
459 pch_probe(struct pci_dev *pdev, const struct pci_device_id *id)
460 {
461 	s32 ret;
462 	unsigned long flags;
463 	struct pch_dev *chip;
464 
465 	chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
466 	if (chip == NULL)
467 		return -ENOMEM;
468 
469 	/* enable the 1588 pci device */
470 	ret = pcim_enable_device(pdev);
471 	if (ret != 0) {
472 		dev_err(&pdev->dev, "could not enable the pci device\n");
473 		return ret;
474 	}
475 
476 	ret = pcim_iomap_regions(pdev, BIT(IO_MEM_BAR), "1588_regs");
477 	if (ret) {
478 		dev_err(&pdev->dev, "could not locate IO memory address\n");
479 		return ret;
480 	}
481 
482 	/* get the virtual address to the 1588 registers */
483 	chip->regs = pcim_iomap_table(pdev)[IO_MEM_BAR];
484 	chip->caps = ptp_pch_caps;
485 	chip->ptp_clock = ptp_clock_register(&chip->caps, &pdev->dev);
486 	if (IS_ERR(chip->ptp_clock))
487 		return PTR_ERR(chip->ptp_clock);
488 
489 	spin_lock_init(&chip->register_lock);
490 
491 	ret = request_irq(pdev->irq, &isr, IRQF_SHARED, KBUILD_MODNAME, chip);
492 	if (ret != 0) {
493 		dev_err(&pdev->dev, "failed to get irq %d\n", pdev->irq);
494 		goto err_req_irq;
495 	}
496 
497 	/* indicate success */
498 	chip->irq = pdev->irq;
499 	chip->pdev = pdev;
500 	pci_set_drvdata(pdev, chip);
501 
502 	spin_lock_irqsave(&chip->register_lock, flags);
503 	/* reset the ieee1588 h/w */
504 	pch_reset(chip);
505 
506 	iowrite32(DEFAULT_ADDEND, &chip->regs->addend);
507 	iowrite64_lo_hi(1, &chip->regs->trgt_lo);
508 	iowrite32(PCH_TSE_TTIPEND, &chip->regs->event);
509 
510 	pch_eth_enable_set(chip);
511 
512 	if (strcmp(pch_param.station, "00:00:00:00:00:00") != 0) {
513 		if (pch_set_station_address(pch_param.station, pdev) != 0) {
514 			dev_err(&pdev->dev,
515 			"Invalid station address parameter\n"
516 			"Module loaded but station address not set correctly\n"
517 			);
518 		}
519 	}
520 	spin_unlock_irqrestore(&chip->register_lock, flags);
521 	return 0;
522 
523 err_req_irq:
524 	ptp_clock_unregister(chip->ptp_clock);
525 
526 	dev_err(&pdev->dev, "probe failed(ret=0x%x)\n", ret);
527 
528 	return ret;
529 }
530 
531 static const struct pci_device_id pch_ieee1588_pcidev_id[] = {
532 	{
533 	  .vendor = PCI_VENDOR_ID_INTEL,
534 	  .device = PCI_DEVICE_ID_PCH_1588
535 	 },
536 	{0}
537 };
538 MODULE_DEVICE_TABLE(pci, pch_ieee1588_pcidev_id);
539 
540 static struct pci_driver pch_driver = {
541 	.name = KBUILD_MODNAME,
542 	.id_table = pch_ieee1588_pcidev_id,
543 	.probe = pch_probe,
544 	.remove = pch_remove,
545 };
546 module_pci_driver(pch_driver);
547 
548 module_param_string(station,
549 		    pch_param.station, sizeof(pch_param.station), 0444);
550 MODULE_PARM_DESC(station,
551 	 "IEEE 1588 station address to use - colon separated hex values");
552 
553 MODULE_AUTHOR("LAPIS SEMICONDUCTOR, <tshimizu818@gmail.com>");
554 MODULE_DESCRIPTION("PTP clock using the EG20T timer");
555 MODULE_LICENSE("GPL");
556