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1/*
2 * drivers/rtc/rtc-pl031.c
3 *
4 * Real Time Clock interface for ARM AMBA PrimeCell 031 RTC
5 *
6 * Author: Deepak Saxena <dsaxena@plexity.net>
7 *
8 * Copyright 2006 (c) MontaVista Software, Inc.
9 *
10 * Author: Mian Yousaf Kaukab <mian.yousaf.kaukab@stericsson.com>
11 * Copyright 2010 (c) ST-Ericsson AB
12 *
13 * This program is free software; you can redistribute it and/or
14 * modify it under the terms of the GNU General Public License
15 * as published by the Free Software Foundation; either version
16 * 2 of the License, or (at your option) any later version.
17 */
18#include <linux/module.h>
19#include <linux/rtc.h>
20#include <linux/init.h>
21#include <linux/interrupt.h>
22#include <linux/amba/bus.h>
23#include <linux/io.h>
24#include <linux/bcd.h>
25#include <linux/delay.h>
26#include <linux/pm_wakeirq.h>
27#include <linux/slab.h>
28
29/*
30 * Register definitions
31 */
32#define RTC_DR 0x00 /* Data read register */
33#define RTC_MR 0x04 /* Match register */
34#define RTC_LR 0x08 /* Data load register */
35#define RTC_CR 0x0c /* Control register */
36#define RTC_IMSC 0x10 /* Interrupt mask and set register */
37#define RTC_RIS 0x14 /* Raw interrupt status register */
38#define RTC_MIS 0x18 /* Masked interrupt status register */
39#define RTC_ICR 0x1c /* Interrupt clear register */
40/* ST variants have additional timer functionality */
41#define RTC_TDR 0x20 /* Timer data read register */
42#define RTC_TLR 0x24 /* Timer data load register */
43#define RTC_TCR 0x28 /* Timer control register */
44#define RTC_YDR 0x30 /* Year data read register */
45#define RTC_YMR 0x34 /* Year match register */
46#define RTC_YLR 0x38 /* Year data load register */
47
48#define RTC_CR_EN (1 << 0) /* counter enable bit */
49#define RTC_CR_CWEN (1 << 26) /* Clockwatch enable bit */
50
51#define RTC_TCR_EN (1 << 1) /* Periodic timer enable bit */
52
53/* Common bit definitions for Interrupt status and control registers */
54#define RTC_BIT_AI (1 << 0) /* Alarm interrupt bit */
55#define RTC_BIT_PI (1 << 1) /* Periodic interrupt bit. ST variants only. */
56
57/* Common bit definations for ST v2 for reading/writing time */
58#define RTC_SEC_SHIFT 0
59#define RTC_SEC_MASK (0x3F << RTC_SEC_SHIFT) /* Second [0-59] */
60#define RTC_MIN_SHIFT 6
61#define RTC_MIN_MASK (0x3F << RTC_MIN_SHIFT) /* Minute [0-59] */
62#define RTC_HOUR_SHIFT 12
63#define RTC_HOUR_MASK (0x1F << RTC_HOUR_SHIFT) /* Hour [0-23] */
64#define RTC_WDAY_SHIFT 17
65#define RTC_WDAY_MASK (0x7 << RTC_WDAY_SHIFT) /* Day of Week [1-7] 1=Sunday */
66#define RTC_MDAY_SHIFT 20
67#define RTC_MDAY_MASK (0x1F << RTC_MDAY_SHIFT) /* Day of Month [1-31] */
68#define RTC_MON_SHIFT 25
69#define RTC_MON_MASK (0xF << RTC_MON_SHIFT) /* Month [1-12] 1=January */
70
71#define RTC_TIMER_FREQ 32768
72
73/**
74 * struct pl031_vendor_data - per-vendor variations
75 * @ops: the vendor-specific operations used on this silicon version
76 * @clockwatch: if this is an ST Microelectronics silicon version with a
77 * clockwatch function
78 * @st_weekday: if this is an ST Microelectronics silicon version that need
79 * the weekday fix
80 * @irqflags: special IRQ flags per variant
81 */
82struct pl031_vendor_data {
83 struct rtc_class_ops ops;
84 bool clockwatch;
85 bool st_weekday;
86 unsigned long irqflags;
87};
88
89struct pl031_local {
90 struct pl031_vendor_data *vendor;
91 struct rtc_device *rtc;
92 void __iomem *base;
93};
94
95static int pl031_alarm_irq_enable(struct device *dev,
96 unsigned int enabled)
97{
98 struct pl031_local *ldata = dev_get_drvdata(dev);
99 unsigned long imsc;
100
101 /* Clear any pending alarm interrupts. */
102 writel(RTC_BIT_AI, ldata->base + RTC_ICR);
103
104 imsc = readl(ldata->base + RTC_IMSC);
105
106 if (enabled == 1)
107 writel(imsc | RTC_BIT_AI, ldata->base + RTC_IMSC);
108 else
109 writel(imsc & ~RTC_BIT_AI, ldata->base + RTC_IMSC);
110
111 return 0;
112}
113
114/*
115 * Convert Gregorian date to ST v2 RTC format.
116 */
117static int pl031_stv2_tm_to_time(struct device *dev,
118 struct rtc_time *tm, unsigned long *st_time,
119 unsigned long *bcd_year)
120{
121 int year = tm->tm_year + 1900;
122 int wday = tm->tm_wday;
123
124 /* wday masking is not working in hardware so wday must be valid */
125 if (wday < -1 || wday > 6) {
126 dev_err(dev, "invalid wday value %d\n", tm->tm_wday);
127 return -EINVAL;
128 } else if (wday == -1) {
129 /* wday is not provided, calculate it here */
130 unsigned long time;
131 struct rtc_time calc_tm;
132
133 rtc_tm_to_time(tm, &time);
134 rtc_time_to_tm(time, &calc_tm);
135 wday = calc_tm.tm_wday;
136 }
137
138 *bcd_year = (bin2bcd(year % 100) | bin2bcd(year / 100) << 8);
139
140 *st_time = ((tm->tm_mon + 1) << RTC_MON_SHIFT)
141 | (tm->tm_mday << RTC_MDAY_SHIFT)
142 | ((wday + 1) << RTC_WDAY_SHIFT)
143 | (tm->tm_hour << RTC_HOUR_SHIFT)
144 | (tm->tm_min << RTC_MIN_SHIFT)
145 | (tm->tm_sec << RTC_SEC_SHIFT);
146
147 return 0;
148}
149
150/*
151 * Convert ST v2 RTC format to Gregorian date.
152 */
153static int pl031_stv2_time_to_tm(unsigned long st_time, unsigned long bcd_year,
154 struct rtc_time *tm)
155{
156 tm->tm_year = bcd2bin(bcd_year) + (bcd2bin(bcd_year >> 8) * 100);
157 tm->tm_mon = ((st_time & RTC_MON_MASK) >> RTC_MON_SHIFT) - 1;
158 tm->tm_mday = ((st_time & RTC_MDAY_MASK) >> RTC_MDAY_SHIFT);
159 tm->tm_wday = ((st_time & RTC_WDAY_MASK) >> RTC_WDAY_SHIFT) - 1;
160 tm->tm_hour = ((st_time & RTC_HOUR_MASK) >> RTC_HOUR_SHIFT);
161 tm->tm_min = ((st_time & RTC_MIN_MASK) >> RTC_MIN_SHIFT);
162 tm->tm_sec = ((st_time & RTC_SEC_MASK) >> RTC_SEC_SHIFT);
163
164 tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
165 tm->tm_year -= 1900;
166
167 return 0;
168}
169
170static int pl031_stv2_read_time(struct device *dev, struct rtc_time *tm)
171{
172 struct pl031_local *ldata = dev_get_drvdata(dev);
173
174 pl031_stv2_time_to_tm(readl(ldata->base + RTC_DR),
175 readl(ldata->base + RTC_YDR), tm);
176
177 return 0;
178}
179
180static int pl031_stv2_set_time(struct device *dev, struct rtc_time *tm)
181{
182 unsigned long time;
183 unsigned long bcd_year;
184 struct pl031_local *ldata = dev_get_drvdata(dev);
185 int ret;
186
187 ret = pl031_stv2_tm_to_time(dev, tm, &time, &bcd_year);
188 if (ret == 0) {
189 writel(bcd_year, ldata->base + RTC_YLR);
190 writel(time, ldata->base + RTC_LR);
191 }
192
193 return ret;
194}
195
196static int pl031_stv2_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
197{
198 struct pl031_local *ldata = dev_get_drvdata(dev);
199 int ret;
200
201 ret = pl031_stv2_time_to_tm(readl(ldata->base + RTC_MR),
202 readl(ldata->base + RTC_YMR), &alarm->time);
203
204 alarm->pending = readl(ldata->base + RTC_RIS) & RTC_BIT_AI;
205 alarm->enabled = readl(ldata->base + RTC_IMSC) & RTC_BIT_AI;
206
207 return ret;
208}
209
210static int pl031_stv2_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
211{
212 struct pl031_local *ldata = dev_get_drvdata(dev);
213 unsigned long time;
214 unsigned long bcd_year;
215 int ret;
216
217 /* At the moment, we can only deal with non-wildcarded alarm times. */
218 ret = rtc_valid_tm(&alarm->time);
219 if (ret == 0) {
220 ret = pl031_stv2_tm_to_time(dev, &alarm->time,
221 &time, &bcd_year);
222 if (ret == 0) {
223 writel(bcd_year, ldata->base + RTC_YMR);
224 writel(time, ldata->base + RTC_MR);
225
226 pl031_alarm_irq_enable(dev, alarm->enabled);
227 }
228 }
229
230 return ret;
231}
232
233static irqreturn_t pl031_interrupt(int irq, void *dev_id)
234{
235 struct pl031_local *ldata = dev_id;
236 unsigned long rtcmis;
237 unsigned long events = 0;
238
239 rtcmis = readl(ldata->base + RTC_MIS);
240 if (rtcmis & RTC_BIT_AI) {
241 writel(RTC_BIT_AI, ldata->base + RTC_ICR);
242 events |= (RTC_AF | RTC_IRQF);
243 rtc_update_irq(ldata->rtc, 1, events);
244
245 return IRQ_HANDLED;
246 }
247
248 return IRQ_NONE;
249}
250
251static int pl031_read_time(struct device *dev, struct rtc_time *tm)
252{
253 struct pl031_local *ldata = dev_get_drvdata(dev);
254
255 rtc_time_to_tm(readl(ldata->base + RTC_DR), tm);
256
257 return 0;
258}
259
260static int pl031_set_time(struct device *dev, struct rtc_time *tm)
261{
262 unsigned long time;
263 struct pl031_local *ldata = dev_get_drvdata(dev);
264 int ret;
265
266 ret = rtc_tm_to_time(tm, &time);
267
268 if (ret == 0)
269 writel(time, ldata->base + RTC_LR);
270
271 return ret;
272}
273
274static int pl031_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
275{
276 struct pl031_local *ldata = dev_get_drvdata(dev);
277
278 rtc_time_to_tm(readl(ldata->base + RTC_MR), &alarm->time);
279
280 alarm->pending = readl(ldata->base + RTC_RIS) & RTC_BIT_AI;
281 alarm->enabled = readl(ldata->base + RTC_IMSC) & RTC_BIT_AI;
282
283 return 0;
284}
285
286static int pl031_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
287{
288 struct pl031_local *ldata = dev_get_drvdata(dev);
289 unsigned long time;
290 int ret;
291
292 /* At the moment, we can only deal with non-wildcarded alarm times. */
293 ret = rtc_valid_tm(&alarm->time);
294 if (ret == 0) {
295 ret = rtc_tm_to_time(&alarm->time, &time);
296 if (ret == 0) {
297 writel(time, ldata->base + RTC_MR);
298 pl031_alarm_irq_enable(dev, alarm->enabled);
299 }
300 }
301
302 return ret;
303}
304
305static int pl031_remove(struct amba_device *adev)
306{
307 struct pl031_local *ldata = dev_get_drvdata(&adev->dev);
308
309 dev_pm_clear_wake_irq(&adev->dev);
310 device_init_wakeup(&adev->dev, false);
311 free_irq(adev->irq[0], ldata);
312 rtc_device_unregister(ldata->rtc);
313 iounmap(ldata->base);
314 kfree(ldata);
315 amba_release_regions(adev);
316
317 return 0;
318}
319
320static int pl031_probe(struct amba_device *adev, const struct amba_id *id)
321{
322 int ret;
323 struct pl031_local *ldata;
324 struct pl031_vendor_data *vendor = id->data;
325 struct rtc_class_ops *ops = &vendor->ops;
326 unsigned long time, data;
327
328 ret = amba_request_regions(adev, NULL);
329 if (ret)
330 goto err_req;
331
332 ldata = kzalloc(sizeof(struct pl031_local), GFP_KERNEL);
333 if (!ldata) {
334 ret = -ENOMEM;
335 goto out;
336 }
337 ldata->vendor = vendor;
338
339 ldata->base = ioremap(adev->res.start, resource_size(&adev->res));
340
341 if (!ldata->base) {
342 ret = -ENOMEM;
343 goto out_no_remap;
344 }
345
346 amba_set_drvdata(adev, ldata);
347
348 dev_dbg(&adev->dev, "designer ID = 0x%02x\n", amba_manf(adev));
349 dev_dbg(&adev->dev, "revision = 0x%01x\n", amba_rev(adev));
350
351 data = readl(ldata->base + RTC_CR);
352 /* Enable the clockwatch on ST Variants */
353 if (vendor->clockwatch)
354 data |= RTC_CR_CWEN;
355 else
356 data |= RTC_CR_EN;
357 writel(data, ldata->base + RTC_CR);
358
359 /*
360 * On ST PL031 variants, the RTC reset value does not provide correct
361 * weekday for 2000-01-01. Correct the erroneous sunday to saturday.
362 */
363 if (vendor->st_weekday) {
364 if (readl(ldata->base + RTC_YDR) == 0x2000) {
365 time = readl(ldata->base + RTC_DR);
366 if ((time &
367 (RTC_MON_MASK | RTC_MDAY_MASK | RTC_WDAY_MASK))
368 == 0x02120000) {
369 time = time | (0x7 << RTC_WDAY_SHIFT);
370 writel(0x2000, ldata->base + RTC_YLR);
371 writel(time, ldata->base + RTC_LR);
372 }
373 }
374 }
375
376 device_init_wakeup(&adev->dev, true);
377 ldata->rtc = rtc_device_register("pl031", &adev->dev, ops,
378 THIS_MODULE);
379 if (IS_ERR(ldata->rtc)) {
380 ret = PTR_ERR(ldata->rtc);
381 goto out_no_rtc;
382 }
383
384 if (request_irq(adev->irq[0], pl031_interrupt,
385 vendor->irqflags, "rtc-pl031", ldata)) {
386 ret = -EIO;
387 goto out_no_irq;
388 }
389 dev_pm_set_wake_irq(&adev->dev, adev->irq[0]);
390 return 0;
391
392out_no_irq:
393 rtc_device_unregister(ldata->rtc);
394out_no_rtc:
395 iounmap(ldata->base);
396out_no_remap:
397 kfree(ldata);
398out:
399 amba_release_regions(adev);
400err_req:
401
402 return ret;
403}
404
405/* Operations for the original ARM version */
406static struct pl031_vendor_data arm_pl031 = {
407 .ops = {
408 .read_time = pl031_read_time,
409 .set_time = pl031_set_time,
410 .read_alarm = pl031_read_alarm,
411 .set_alarm = pl031_set_alarm,
412 .alarm_irq_enable = pl031_alarm_irq_enable,
413 },
414};
415
416/* The First ST derivative */
417static struct pl031_vendor_data stv1_pl031 = {
418 .ops = {
419 .read_time = pl031_read_time,
420 .set_time = pl031_set_time,
421 .read_alarm = pl031_read_alarm,
422 .set_alarm = pl031_set_alarm,
423 .alarm_irq_enable = pl031_alarm_irq_enable,
424 },
425 .clockwatch = true,
426 .st_weekday = true,
427};
428
429/* And the second ST derivative */
430static struct pl031_vendor_data stv2_pl031 = {
431 .ops = {
432 .read_time = pl031_stv2_read_time,
433 .set_time = pl031_stv2_set_time,
434 .read_alarm = pl031_stv2_read_alarm,
435 .set_alarm = pl031_stv2_set_alarm,
436 .alarm_irq_enable = pl031_alarm_irq_enable,
437 },
438 .clockwatch = true,
439 .st_weekday = true,
440 /*
441 * This variant shares the IRQ with another block and must not
442 * suspend that IRQ line.
443 * TODO check if it shares with IRQF_NO_SUSPEND user, else we can
444 * remove IRQF_COND_SUSPEND
445 */
446 .irqflags = IRQF_SHARED | IRQF_COND_SUSPEND,
447};
448
449static struct amba_id pl031_ids[] = {
450 {
451 .id = 0x00041031,
452 .mask = 0x000fffff,
453 .data = &arm_pl031,
454 },
455 /* ST Micro variants */
456 {
457 .id = 0x00180031,
458 .mask = 0x00ffffff,
459 .data = &stv1_pl031,
460 },
461 {
462 .id = 0x00280031,
463 .mask = 0x00ffffff,
464 .data = &stv2_pl031,
465 },
466 {0, 0},
467};
468
469MODULE_DEVICE_TABLE(amba, pl031_ids);
470
471static struct amba_driver pl031_driver = {
472 .drv = {
473 .name = "rtc-pl031",
474 },
475 .id_table = pl031_ids,
476 .probe = pl031_probe,
477 .remove = pl031_remove,
478};
479
480module_amba_driver(pl031_driver);
481
482MODULE_AUTHOR("Deepak Saxena <dsaxena@plexity.net>");
483MODULE_DESCRIPTION("ARM AMBA PL031 RTC Driver");
484MODULE_LICENSE("GPL");
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * drivers/rtc/rtc-pl031.c
4 *
5 * Real Time Clock interface for ARM AMBA PrimeCell 031 RTC
6 *
7 * Author: Deepak Saxena <dsaxena@plexity.net>
8 *
9 * Copyright 2006 (c) MontaVista Software, Inc.
10 *
11 * Author: Mian Yousaf Kaukab <mian.yousaf.kaukab@stericsson.com>
12 * Copyright 2010 (c) ST-Ericsson AB
13 */
14#include <linux/module.h>
15#include <linux/rtc.h>
16#include <linux/init.h>
17#include <linux/interrupt.h>
18#include <linux/amba/bus.h>
19#include <linux/io.h>
20#include <linux/bcd.h>
21#include <linux/delay.h>
22#include <linux/pm_wakeirq.h>
23#include <linux/slab.h>
24
25/*
26 * Register definitions
27 */
28#define RTC_DR 0x00 /* Data read register */
29#define RTC_MR 0x04 /* Match register */
30#define RTC_LR 0x08 /* Data load register */
31#define RTC_CR 0x0c /* Control register */
32#define RTC_IMSC 0x10 /* Interrupt mask and set register */
33#define RTC_RIS 0x14 /* Raw interrupt status register */
34#define RTC_MIS 0x18 /* Masked interrupt status register */
35#define RTC_ICR 0x1c /* Interrupt clear register */
36/* ST variants have additional timer functionality */
37#define RTC_TDR 0x20 /* Timer data read register */
38#define RTC_TLR 0x24 /* Timer data load register */
39#define RTC_TCR 0x28 /* Timer control register */
40#define RTC_YDR 0x30 /* Year data read register */
41#define RTC_YMR 0x34 /* Year match register */
42#define RTC_YLR 0x38 /* Year data load register */
43
44#define RTC_CR_EN (1 << 0) /* counter enable bit */
45#define RTC_CR_CWEN (1 << 26) /* Clockwatch enable bit */
46
47#define RTC_TCR_EN (1 << 1) /* Periodic timer enable bit */
48
49/* Common bit definitions for Interrupt status and control registers */
50#define RTC_BIT_AI (1 << 0) /* Alarm interrupt bit */
51#define RTC_BIT_PI (1 << 1) /* Periodic interrupt bit. ST variants only. */
52
53/* Common bit definations for ST v2 for reading/writing time */
54#define RTC_SEC_SHIFT 0
55#define RTC_SEC_MASK (0x3F << RTC_SEC_SHIFT) /* Second [0-59] */
56#define RTC_MIN_SHIFT 6
57#define RTC_MIN_MASK (0x3F << RTC_MIN_SHIFT) /* Minute [0-59] */
58#define RTC_HOUR_SHIFT 12
59#define RTC_HOUR_MASK (0x1F << RTC_HOUR_SHIFT) /* Hour [0-23] */
60#define RTC_WDAY_SHIFT 17
61#define RTC_WDAY_MASK (0x7 << RTC_WDAY_SHIFT) /* Day of Week [1-7] 1=Sunday */
62#define RTC_MDAY_SHIFT 20
63#define RTC_MDAY_MASK (0x1F << RTC_MDAY_SHIFT) /* Day of Month [1-31] */
64#define RTC_MON_SHIFT 25
65#define RTC_MON_MASK (0xF << RTC_MON_SHIFT) /* Month [1-12] 1=January */
66
67#define RTC_TIMER_FREQ 32768
68
69/**
70 * struct pl031_vendor_data - per-vendor variations
71 * @ops: the vendor-specific operations used on this silicon version
72 * @clockwatch: if this is an ST Microelectronics silicon version with a
73 * clockwatch function
74 * @st_weekday: if this is an ST Microelectronics silicon version that need
75 * the weekday fix
76 * @irqflags: special IRQ flags per variant
77 */
78struct pl031_vendor_data {
79 struct rtc_class_ops ops;
80 bool clockwatch;
81 bool st_weekday;
82 unsigned long irqflags;
83 time64_t range_min;
84 timeu64_t range_max;
85};
86
87struct pl031_local {
88 struct pl031_vendor_data *vendor;
89 struct rtc_device *rtc;
90 void __iomem *base;
91};
92
93static int pl031_alarm_irq_enable(struct device *dev,
94 unsigned int enabled)
95{
96 struct pl031_local *ldata = dev_get_drvdata(dev);
97 unsigned long imsc;
98
99 /* Clear any pending alarm interrupts. */
100 writel(RTC_BIT_AI, ldata->base + RTC_ICR);
101
102 imsc = readl(ldata->base + RTC_IMSC);
103
104 if (enabled == 1)
105 writel(imsc | RTC_BIT_AI, ldata->base + RTC_IMSC);
106 else
107 writel(imsc & ~RTC_BIT_AI, ldata->base + RTC_IMSC);
108
109 return 0;
110}
111
112/*
113 * Convert Gregorian date to ST v2 RTC format.
114 */
115static int pl031_stv2_tm_to_time(struct device *dev,
116 struct rtc_time *tm, unsigned long *st_time,
117 unsigned long *bcd_year)
118{
119 int year = tm->tm_year + 1900;
120 int wday = tm->tm_wday;
121
122 /* wday masking is not working in hardware so wday must be valid */
123 if (wday < -1 || wday > 6) {
124 dev_err(dev, "invalid wday value %d\n", tm->tm_wday);
125 return -EINVAL;
126 } else if (wday == -1) {
127 /* wday is not provided, calculate it here */
128 struct rtc_time calc_tm;
129
130 rtc_time64_to_tm(rtc_tm_to_time64(tm), &calc_tm);
131 wday = calc_tm.tm_wday;
132 }
133
134 *bcd_year = (bin2bcd(year % 100) | bin2bcd(year / 100) << 8);
135
136 *st_time = ((tm->tm_mon + 1) << RTC_MON_SHIFT)
137 | (tm->tm_mday << RTC_MDAY_SHIFT)
138 | ((wday + 1) << RTC_WDAY_SHIFT)
139 | (tm->tm_hour << RTC_HOUR_SHIFT)
140 | (tm->tm_min << RTC_MIN_SHIFT)
141 | (tm->tm_sec << RTC_SEC_SHIFT);
142
143 return 0;
144}
145
146/*
147 * Convert ST v2 RTC format to Gregorian date.
148 */
149static int pl031_stv2_time_to_tm(unsigned long st_time, unsigned long bcd_year,
150 struct rtc_time *tm)
151{
152 tm->tm_year = bcd2bin(bcd_year) + (bcd2bin(bcd_year >> 8) * 100);
153 tm->tm_mon = ((st_time & RTC_MON_MASK) >> RTC_MON_SHIFT) - 1;
154 tm->tm_mday = ((st_time & RTC_MDAY_MASK) >> RTC_MDAY_SHIFT);
155 tm->tm_wday = ((st_time & RTC_WDAY_MASK) >> RTC_WDAY_SHIFT) - 1;
156 tm->tm_hour = ((st_time & RTC_HOUR_MASK) >> RTC_HOUR_SHIFT);
157 tm->tm_min = ((st_time & RTC_MIN_MASK) >> RTC_MIN_SHIFT);
158 tm->tm_sec = ((st_time & RTC_SEC_MASK) >> RTC_SEC_SHIFT);
159
160 tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year);
161 tm->tm_year -= 1900;
162
163 return 0;
164}
165
166static int pl031_stv2_read_time(struct device *dev, struct rtc_time *tm)
167{
168 struct pl031_local *ldata = dev_get_drvdata(dev);
169
170 pl031_stv2_time_to_tm(readl(ldata->base + RTC_DR),
171 readl(ldata->base + RTC_YDR), tm);
172
173 return 0;
174}
175
176static int pl031_stv2_set_time(struct device *dev, struct rtc_time *tm)
177{
178 unsigned long time;
179 unsigned long bcd_year;
180 struct pl031_local *ldata = dev_get_drvdata(dev);
181 int ret;
182
183 ret = pl031_stv2_tm_to_time(dev, tm, &time, &bcd_year);
184 if (ret == 0) {
185 writel(bcd_year, ldata->base + RTC_YLR);
186 writel(time, ldata->base + RTC_LR);
187 }
188
189 return ret;
190}
191
192static int pl031_stv2_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
193{
194 struct pl031_local *ldata = dev_get_drvdata(dev);
195 int ret;
196
197 ret = pl031_stv2_time_to_tm(readl(ldata->base + RTC_MR),
198 readl(ldata->base + RTC_YMR), &alarm->time);
199
200 alarm->pending = readl(ldata->base + RTC_RIS) & RTC_BIT_AI;
201 alarm->enabled = readl(ldata->base + RTC_IMSC) & RTC_BIT_AI;
202
203 return ret;
204}
205
206static int pl031_stv2_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
207{
208 struct pl031_local *ldata = dev_get_drvdata(dev);
209 unsigned long time;
210 unsigned long bcd_year;
211 int ret;
212
213 ret = pl031_stv2_tm_to_time(dev, &alarm->time,
214 &time, &bcd_year);
215 if (ret == 0) {
216 writel(bcd_year, ldata->base + RTC_YMR);
217 writel(time, ldata->base + RTC_MR);
218
219 pl031_alarm_irq_enable(dev, alarm->enabled);
220 }
221
222 return ret;
223}
224
225static irqreturn_t pl031_interrupt(int irq, void *dev_id)
226{
227 struct pl031_local *ldata = dev_id;
228 unsigned long rtcmis;
229 unsigned long events = 0;
230
231 rtcmis = readl(ldata->base + RTC_MIS);
232 if (rtcmis & RTC_BIT_AI) {
233 writel(RTC_BIT_AI, ldata->base + RTC_ICR);
234 events |= (RTC_AF | RTC_IRQF);
235 rtc_update_irq(ldata->rtc, 1, events);
236
237 return IRQ_HANDLED;
238 }
239
240 return IRQ_NONE;
241}
242
243static int pl031_read_time(struct device *dev, struct rtc_time *tm)
244{
245 struct pl031_local *ldata = dev_get_drvdata(dev);
246
247 rtc_time64_to_tm(readl(ldata->base + RTC_DR), tm);
248
249 return 0;
250}
251
252static int pl031_set_time(struct device *dev, struct rtc_time *tm)
253{
254 struct pl031_local *ldata = dev_get_drvdata(dev);
255
256 writel(rtc_tm_to_time64(tm), ldata->base + RTC_LR);
257
258 return 0;
259}
260
261static int pl031_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
262{
263 struct pl031_local *ldata = dev_get_drvdata(dev);
264
265 rtc_time64_to_tm(readl(ldata->base + RTC_MR), &alarm->time);
266
267 alarm->pending = readl(ldata->base + RTC_RIS) & RTC_BIT_AI;
268 alarm->enabled = readl(ldata->base + RTC_IMSC) & RTC_BIT_AI;
269
270 return 0;
271}
272
273static int pl031_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
274{
275 struct pl031_local *ldata = dev_get_drvdata(dev);
276
277 writel(rtc_tm_to_time64(&alarm->time), ldata->base + RTC_MR);
278 pl031_alarm_irq_enable(dev, alarm->enabled);
279
280 return 0;
281}
282
283static int pl031_remove(struct amba_device *adev)
284{
285 struct pl031_local *ldata = dev_get_drvdata(&adev->dev);
286
287 dev_pm_clear_wake_irq(&adev->dev);
288 device_init_wakeup(&adev->dev, false);
289 if (adev->irq[0])
290 free_irq(adev->irq[0], ldata);
291 amba_release_regions(adev);
292
293 return 0;
294}
295
296static int pl031_probe(struct amba_device *adev, const struct amba_id *id)
297{
298 int ret;
299 struct pl031_local *ldata;
300 struct pl031_vendor_data *vendor = id->data;
301 struct rtc_class_ops *ops;
302 unsigned long time, data;
303
304 ret = amba_request_regions(adev, NULL);
305 if (ret)
306 goto err_req;
307
308 ldata = devm_kzalloc(&adev->dev, sizeof(struct pl031_local),
309 GFP_KERNEL);
310 ops = devm_kmemdup(&adev->dev, &vendor->ops, sizeof(vendor->ops),
311 GFP_KERNEL);
312 if (!ldata || !ops) {
313 ret = -ENOMEM;
314 goto out;
315 }
316
317 ldata->vendor = vendor;
318 ldata->base = devm_ioremap(&adev->dev, adev->res.start,
319 resource_size(&adev->res));
320 if (!ldata->base) {
321 ret = -ENOMEM;
322 goto out;
323 }
324
325 amba_set_drvdata(adev, ldata);
326
327 dev_dbg(&adev->dev, "designer ID = 0x%02x\n", amba_manf(adev));
328 dev_dbg(&adev->dev, "revision = 0x%01x\n", amba_rev(adev));
329
330 data = readl(ldata->base + RTC_CR);
331 /* Enable the clockwatch on ST Variants */
332 if (vendor->clockwatch)
333 data |= RTC_CR_CWEN;
334 else
335 data |= RTC_CR_EN;
336 writel(data, ldata->base + RTC_CR);
337
338 /*
339 * On ST PL031 variants, the RTC reset value does not provide correct
340 * weekday for 2000-01-01. Correct the erroneous sunday to saturday.
341 */
342 if (vendor->st_weekday) {
343 if (readl(ldata->base + RTC_YDR) == 0x2000) {
344 time = readl(ldata->base + RTC_DR);
345 if ((time &
346 (RTC_MON_MASK | RTC_MDAY_MASK | RTC_WDAY_MASK))
347 == 0x02120000) {
348 time = time | (0x7 << RTC_WDAY_SHIFT);
349 writel(0x2000, ldata->base + RTC_YLR);
350 writel(time, ldata->base + RTC_LR);
351 }
352 }
353 }
354
355 if (!adev->irq[0]) {
356 /* When there's no interrupt, no point in exposing the alarm */
357 ops->read_alarm = NULL;
358 ops->set_alarm = NULL;
359 ops->alarm_irq_enable = NULL;
360 }
361
362 device_init_wakeup(&adev->dev, true);
363 ldata->rtc = devm_rtc_allocate_device(&adev->dev);
364 if (IS_ERR(ldata->rtc))
365 return PTR_ERR(ldata->rtc);
366
367 ldata->rtc->ops = ops;
368 ldata->rtc->range_min = vendor->range_min;
369 ldata->rtc->range_max = vendor->range_max;
370
371 ret = rtc_register_device(ldata->rtc);
372 if (ret)
373 goto out;
374
375 if (adev->irq[0]) {
376 ret = request_irq(adev->irq[0], pl031_interrupt,
377 vendor->irqflags, "rtc-pl031", ldata);
378 if (ret)
379 goto out;
380 dev_pm_set_wake_irq(&adev->dev, adev->irq[0]);
381 }
382 return 0;
383
384out:
385 amba_release_regions(adev);
386err_req:
387
388 return ret;
389}
390
391/* Operations for the original ARM version */
392static struct pl031_vendor_data arm_pl031 = {
393 .ops = {
394 .read_time = pl031_read_time,
395 .set_time = pl031_set_time,
396 .read_alarm = pl031_read_alarm,
397 .set_alarm = pl031_set_alarm,
398 .alarm_irq_enable = pl031_alarm_irq_enable,
399 },
400 .range_max = U32_MAX,
401};
402
403/* The First ST derivative */
404static struct pl031_vendor_data stv1_pl031 = {
405 .ops = {
406 .read_time = pl031_read_time,
407 .set_time = pl031_set_time,
408 .read_alarm = pl031_read_alarm,
409 .set_alarm = pl031_set_alarm,
410 .alarm_irq_enable = pl031_alarm_irq_enable,
411 },
412 .clockwatch = true,
413 .st_weekday = true,
414 .range_max = U32_MAX,
415};
416
417/* And the second ST derivative */
418static struct pl031_vendor_data stv2_pl031 = {
419 .ops = {
420 .read_time = pl031_stv2_read_time,
421 .set_time = pl031_stv2_set_time,
422 .read_alarm = pl031_stv2_read_alarm,
423 .set_alarm = pl031_stv2_set_alarm,
424 .alarm_irq_enable = pl031_alarm_irq_enable,
425 },
426 .clockwatch = true,
427 .st_weekday = true,
428 /*
429 * This variant shares the IRQ with another block and must not
430 * suspend that IRQ line.
431 * TODO check if it shares with IRQF_NO_SUSPEND user, else we can
432 * remove IRQF_COND_SUSPEND
433 */
434 .irqflags = IRQF_SHARED | IRQF_COND_SUSPEND,
435 .range_min = RTC_TIMESTAMP_BEGIN_0000,
436 .range_max = RTC_TIMESTAMP_END_9999,
437};
438
439static const struct amba_id pl031_ids[] = {
440 {
441 .id = 0x00041031,
442 .mask = 0x000fffff,
443 .data = &arm_pl031,
444 },
445 /* ST Micro variants */
446 {
447 .id = 0x00180031,
448 .mask = 0x00ffffff,
449 .data = &stv1_pl031,
450 },
451 {
452 .id = 0x00280031,
453 .mask = 0x00ffffff,
454 .data = &stv2_pl031,
455 },
456 {0, 0},
457};
458
459MODULE_DEVICE_TABLE(amba, pl031_ids);
460
461static struct amba_driver pl031_driver = {
462 .drv = {
463 .name = "rtc-pl031",
464 },
465 .id_table = pl031_ids,
466 .probe = pl031_probe,
467 .remove = pl031_remove,
468};
469
470module_amba_driver(pl031_driver);
471
472MODULE_AUTHOR("Deepak Saxena <dsaxena@plexity.net>");
473MODULE_DESCRIPTION("ARM AMBA PL031 RTC Driver");
474MODULE_LICENSE("GPL");