Commit | Line | Data |
---|---|---|
8ae6e163 DS |
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 | * | |
c72881e8 LW |
10 | * Author: Mian Yousaf Kaukab <mian.yousaf.kaukab@stericsson.com> |
11 | * Copyright 2010 (c) ST-Ericsson AB | |
12 | * | |
8ae6e163 DS |
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 | */ | |
8ae6e163 DS |
18 | #include <linux/module.h> |
19 | #include <linux/rtc.h> | |
20 | #include <linux/init.h> | |
8ae6e163 | 21 | #include <linux/interrupt.h> |
8ae6e163 | 22 | #include <linux/amba/bus.h> |
2dba8518 | 23 | #include <linux/io.h> |
c72881e8 LW |
24 | #include <linux/bcd.h> |
25 | #include <linux/delay.h> | |
5a0e3ad6 | 26 | #include <linux/slab.h> |
8ae6e163 DS |
27 | |
28 | /* | |
29 | * Register definitions | |
30 | */ | |
31 | #define RTC_DR 0x00 /* Data read register */ | |
32 | #define RTC_MR 0x04 /* Match register */ | |
33 | #define RTC_LR 0x08 /* Data load register */ | |
34 | #define RTC_CR 0x0c /* Control register */ | |
35 | #define RTC_IMSC 0x10 /* Interrupt mask and set register */ | |
36 | #define RTC_RIS 0x14 /* Raw interrupt status register */ | |
37 | #define RTC_MIS 0x18 /* Masked interrupt status register */ | |
38 | #define RTC_ICR 0x1c /* Interrupt clear register */ | |
c72881e8 LW |
39 | /* ST variants have additional timer functionality */ |
40 | #define RTC_TDR 0x20 /* Timer data read register */ | |
41 | #define RTC_TLR 0x24 /* Timer data load register */ | |
42 | #define RTC_TCR 0x28 /* Timer control register */ | |
43 | #define RTC_YDR 0x30 /* Year data read register */ | |
44 | #define RTC_YMR 0x34 /* Year match register */ | |
45 | #define RTC_YLR 0x38 /* Year data load register */ | |
46 | ||
47 | #define RTC_CR_CWEN (1 << 26) /* Clockwatch enable bit */ | |
48 | ||
49 | #define RTC_TCR_EN (1 << 1) /* Periodic timer enable bit */ | |
50 | ||
51 | /* Common bit definitions for Interrupt status and control registers */ | |
52 | #define RTC_BIT_AI (1 << 0) /* Alarm interrupt bit */ | |
53 | #define RTC_BIT_PI (1 << 1) /* Periodic interrupt bit. ST variants only. */ | |
54 | ||
55 | /* Common bit definations for ST v2 for reading/writing time */ | |
56 | #define RTC_SEC_SHIFT 0 | |
57 | #define RTC_SEC_MASK (0x3F << RTC_SEC_SHIFT) /* Second [0-59] */ | |
58 | #define RTC_MIN_SHIFT 6 | |
59 | #define RTC_MIN_MASK (0x3F << RTC_MIN_SHIFT) /* Minute [0-59] */ | |
60 | #define RTC_HOUR_SHIFT 12 | |
61 | #define RTC_HOUR_MASK (0x1F << RTC_HOUR_SHIFT) /* Hour [0-23] */ | |
62 | #define RTC_WDAY_SHIFT 17 | |
63 | #define RTC_WDAY_MASK (0x7 << RTC_WDAY_SHIFT) /* Day of Week [1-7] 1=Sunday */ | |
64 | #define RTC_MDAY_SHIFT 20 | |
65 | #define RTC_MDAY_MASK (0x1F << RTC_MDAY_SHIFT) /* Day of Month [1-31] */ | |
66 | #define RTC_MON_SHIFT 25 | |
67 | #define RTC_MON_MASK (0xF << RTC_MON_SHIFT) /* Month [1-12] 1=January */ | |
68 | ||
69 | #define RTC_TIMER_FREQ 32768 | |
8ae6e163 DS |
70 | |
71 | struct pl031_local { | |
72 | struct rtc_device *rtc; | |
73 | void __iomem *base; | |
c72881e8 LW |
74 | u8 hw_designer; |
75 | u8 hw_revision:4; | |
8ae6e163 DS |
76 | }; |
77 | ||
c72881e8 LW |
78 | static int pl031_alarm_irq_enable(struct device *dev, |
79 | unsigned int enabled) | |
80 | { | |
81 | struct pl031_local *ldata = dev_get_drvdata(dev); | |
82 | unsigned long imsc; | |
83 | ||
84 | /* Clear any pending alarm interrupts. */ | |
85 | writel(RTC_BIT_AI, ldata->base + RTC_ICR); | |
86 | ||
87 | imsc = readl(ldata->base + RTC_IMSC); | |
88 | ||
89 | if (enabled == 1) | |
90 | writel(imsc | RTC_BIT_AI, ldata->base + RTC_IMSC); | |
91 | else | |
92 | writel(imsc & ~RTC_BIT_AI, ldata->base + RTC_IMSC); | |
93 | ||
94 | return 0; | |
95 | } | |
96 | ||
97 | /* | |
98 | * Convert Gregorian date to ST v2 RTC format. | |
99 | */ | |
100 | static int pl031_stv2_tm_to_time(struct device *dev, | |
101 | struct rtc_time *tm, unsigned long *st_time, | |
102 | unsigned long *bcd_year) | |
103 | { | |
104 | int year = tm->tm_year + 1900; | |
105 | int wday = tm->tm_wday; | |
106 | ||
107 | /* wday masking is not working in hardware so wday must be valid */ | |
108 | if (wday < -1 || wday > 6) { | |
109 | dev_err(dev, "invalid wday value %d\n", tm->tm_wday); | |
110 | return -EINVAL; | |
111 | } else if (wday == -1) { | |
112 | /* wday is not provided, calculate it here */ | |
113 | unsigned long time; | |
114 | struct rtc_time calc_tm; | |
115 | ||
116 | rtc_tm_to_time(tm, &time); | |
117 | rtc_time_to_tm(time, &calc_tm); | |
118 | wday = calc_tm.tm_wday; | |
119 | } | |
120 | ||
121 | *bcd_year = (bin2bcd(year % 100) | bin2bcd(year / 100) << 8); | |
122 | ||
123 | *st_time = ((tm->tm_mon + 1) << RTC_MON_SHIFT) | |
124 | | (tm->tm_mday << RTC_MDAY_SHIFT) | |
125 | | ((wday + 1) << RTC_WDAY_SHIFT) | |
126 | | (tm->tm_hour << RTC_HOUR_SHIFT) | |
127 | | (tm->tm_min << RTC_MIN_SHIFT) | |
128 | | (tm->tm_sec << RTC_SEC_SHIFT); | |
129 | ||
130 | return 0; | |
131 | } | |
132 | ||
133 | /* | |
134 | * Convert ST v2 RTC format to Gregorian date. | |
135 | */ | |
136 | static int pl031_stv2_time_to_tm(unsigned long st_time, unsigned long bcd_year, | |
137 | struct rtc_time *tm) | |
138 | { | |
139 | tm->tm_year = bcd2bin(bcd_year) + (bcd2bin(bcd_year >> 8) * 100); | |
140 | tm->tm_mon = ((st_time & RTC_MON_MASK) >> RTC_MON_SHIFT) - 1; | |
141 | tm->tm_mday = ((st_time & RTC_MDAY_MASK) >> RTC_MDAY_SHIFT); | |
142 | tm->tm_wday = ((st_time & RTC_WDAY_MASK) >> RTC_WDAY_SHIFT) - 1; | |
143 | tm->tm_hour = ((st_time & RTC_HOUR_MASK) >> RTC_HOUR_SHIFT); | |
144 | tm->tm_min = ((st_time & RTC_MIN_MASK) >> RTC_MIN_SHIFT); | |
145 | tm->tm_sec = ((st_time & RTC_SEC_MASK) >> RTC_SEC_SHIFT); | |
146 | ||
147 | tm->tm_yday = rtc_year_days(tm->tm_mday, tm->tm_mon, tm->tm_year); | |
148 | tm->tm_year -= 1900; | |
149 | ||
150 | return 0; | |
151 | } | |
152 | ||
153 | static int pl031_stv2_read_time(struct device *dev, struct rtc_time *tm) | |
154 | { | |
155 | struct pl031_local *ldata = dev_get_drvdata(dev); | |
156 | ||
157 | pl031_stv2_time_to_tm(readl(ldata->base + RTC_DR), | |
158 | readl(ldata->base + RTC_YDR), tm); | |
159 | ||
160 | return 0; | |
161 | } | |
162 | ||
163 | static int pl031_stv2_set_time(struct device *dev, struct rtc_time *tm) | |
164 | { | |
165 | unsigned long time; | |
166 | unsigned long bcd_year; | |
167 | struct pl031_local *ldata = dev_get_drvdata(dev); | |
168 | int ret; | |
169 | ||
170 | ret = pl031_stv2_tm_to_time(dev, tm, &time, &bcd_year); | |
171 | if (ret == 0) { | |
172 | writel(bcd_year, ldata->base + RTC_YLR); | |
173 | writel(time, ldata->base + RTC_LR); | |
174 | } | |
175 | ||
176 | return ret; | |
177 | } | |
178 | ||
179 | static int pl031_stv2_read_alarm(struct device *dev, struct rtc_wkalrm *alarm) | |
8ae6e163 | 180 | { |
c72881e8 LW |
181 | struct pl031_local *ldata = dev_get_drvdata(dev); |
182 | int ret; | |
8ae6e163 | 183 | |
c72881e8 LW |
184 | ret = pl031_stv2_time_to_tm(readl(ldata->base + RTC_MR), |
185 | readl(ldata->base + RTC_YMR), &alarm->time); | |
8ae6e163 | 186 | |
c72881e8 LW |
187 | alarm->pending = readl(ldata->base + RTC_RIS) & RTC_BIT_AI; |
188 | alarm->enabled = readl(ldata->base + RTC_IMSC) & RTC_BIT_AI; | |
189 | ||
190 | return ret; | |
8ae6e163 DS |
191 | } |
192 | ||
c72881e8 | 193 | static int pl031_stv2_set_alarm(struct device *dev, struct rtc_wkalrm *alarm) |
8ae6e163 DS |
194 | { |
195 | struct pl031_local *ldata = dev_get_drvdata(dev); | |
c72881e8 LW |
196 | unsigned long time; |
197 | unsigned long bcd_year; | |
198 | int ret; | |
199 | ||
200 | /* At the moment, we can only deal with non-wildcarded alarm times. */ | |
201 | ret = rtc_valid_tm(&alarm->time); | |
202 | if (ret == 0) { | |
203 | ret = pl031_stv2_tm_to_time(dev, &alarm->time, | |
204 | &time, &bcd_year); | |
205 | if (ret == 0) { | |
206 | writel(bcd_year, ldata->base + RTC_YMR); | |
207 | writel(time, ldata->base + RTC_MR); | |
208 | ||
209 | pl031_alarm_irq_enable(dev, alarm->enabled); | |
210 | } | |
211 | } | |
212 | ||
213 | return ret; | |
214 | } | |
215 | ||
216 | static irqreturn_t pl031_interrupt(int irq, void *dev_id) | |
217 | { | |
218 | struct pl031_local *ldata = dev_id; | |
219 | unsigned long rtcmis; | |
220 | unsigned long events = 0; | |
221 | ||
222 | rtcmis = readl(ldata->base + RTC_MIS); | |
ac2dee59 RK |
223 | if (rtcmis & RTC_BIT_AI) { |
224 | writel(RTC_BIT_AI, ldata->base + RTC_ICR); | |
225 | events |= (RTC_AF | RTC_IRQF); | |
c72881e8 | 226 | rtc_update_irq(ldata->rtc, 1, events); |
8ae6e163 | 227 | |
c72881e8 | 228 | return IRQ_HANDLED; |
8ae6e163 DS |
229 | } |
230 | ||
c72881e8 | 231 | return IRQ_NONE; |
8ae6e163 DS |
232 | } |
233 | ||
234 | static int pl031_read_time(struct device *dev, struct rtc_time *tm) | |
235 | { | |
236 | struct pl031_local *ldata = dev_get_drvdata(dev); | |
237 | ||
2934d6a8 | 238 | rtc_time_to_tm(readl(ldata->base + RTC_DR), tm); |
8ae6e163 DS |
239 | |
240 | return 0; | |
241 | } | |
242 | ||
243 | static int pl031_set_time(struct device *dev, struct rtc_time *tm) | |
244 | { | |
245 | unsigned long time; | |
246 | struct pl031_local *ldata = dev_get_drvdata(dev); | |
c72881e8 | 247 | int ret; |
8ae6e163 | 248 | |
c72881e8 | 249 | ret = rtc_tm_to_time(tm, &time); |
8ae6e163 | 250 | |
c72881e8 LW |
251 | if (ret == 0) |
252 | writel(time, ldata->base + RTC_LR); | |
253 | ||
254 | return ret; | |
8ae6e163 DS |
255 | } |
256 | ||
257 | static int pl031_read_alarm(struct device *dev, struct rtc_wkalrm *alarm) | |
258 | { | |
259 | struct pl031_local *ldata = dev_get_drvdata(dev); | |
260 | ||
2934d6a8 | 261 | rtc_time_to_tm(readl(ldata->base + RTC_MR), &alarm->time); |
c72881e8 LW |
262 | |
263 | alarm->pending = readl(ldata->base + RTC_RIS) & RTC_BIT_AI; | |
264 | alarm->enabled = readl(ldata->base + RTC_IMSC) & RTC_BIT_AI; | |
8ae6e163 DS |
265 | |
266 | return 0; | |
267 | } | |
268 | ||
269 | static int pl031_set_alarm(struct device *dev, struct rtc_wkalrm *alarm) | |
270 | { | |
271 | struct pl031_local *ldata = dev_get_drvdata(dev); | |
272 | unsigned long time; | |
c72881e8 LW |
273 | int ret; |
274 | ||
275 | /* At the moment, we can only deal with non-wildcarded alarm times. */ | |
276 | ret = rtc_valid_tm(&alarm->time); | |
277 | if (ret == 0) { | |
278 | ret = rtc_tm_to_time(&alarm->time, &time); | |
279 | if (ret == 0) { | |
280 | writel(time, ldata->base + RTC_MR); | |
281 | pl031_alarm_irq_enable(dev, alarm->enabled); | |
282 | } | |
283 | } | |
284 | ||
285 | return ret; | |
286 | } | |
287 | ||
8ae6e163 DS |
288 | static int pl031_remove(struct amba_device *adev) |
289 | { | |
290 | struct pl031_local *ldata = dev_get_drvdata(&adev->dev); | |
291 | ||
2dba8518 RK |
292 | amba_set_drvdata(adev, NULL); |
293 | free_irq(adev->irq[0], ldata->rtc); | |
294 | rtc_device_unregister(ldata->rtc); | |
295 | iounmap(ldata->base); | |
296 | kfree(ldata); | |
297 | amba_release_regions(adev); | |
8ae6e163 DS |
298 | |
299 | return 0; | |
300 | } | |
301 | ||
aa25afad | 302 | static int pl031_probe(struct amba_device *adev, const struct amba_id *id) |
8ae6e163 DS |
303 | { |
304 | int ret; | |
305 | struct pl031_local *ldata; | |
c72881e8 | 306 | struct rtc_class_ops *ops = id->data; |
c0a5f4a0 | 307 | unsigned long time; |
8ae6e163 | 308 | |
2dba8518 RK |
309 | ret = amba_request_regions(adev, NULL); |
310 | if (ret) | |
311 | goto err_req; | |
8ae6e163 | 312 | |
c72881e8 | 313 | ldata = kzalloc(sizeof(struct pl031_local), GFP_KERNEL); |
8ae6e163 DS |
314 | if (!ldata) { |
315 | ret = -ENOMEM; | |
316 | goto out; | |
317 | } | |
8ae6e163 | 318 | |
dc890c2d | 319 | ldata->base = ioremap(adev->res.start, resource_size(&adev->res)); |
c72881e8 | 320 | |
8ae6e163 DS |
321 | if (!ldata->base) { |
322 | ret = -ENOMEM; | |
323 | goto out_no_remap; | |
324 | } | |
325 | ||
2dba8518 RK |
326 | amba_set_drvdata(adev, ldata); |
327 | ||
c72881e8 LW |
328 | ldata->hw_designer = amba_manf(adev); |
329 | ldata->hw_revision = amba_rev(adev); | |
330 | ||
331 | dev_dbg(&adev->dev, "designer ID = 0x%02x\n", ldata->hw_designer); | |
332 | dev_dbg(&adev->dev, "revision = 0x%01x\n", ldata->hw_revision); | |
8ae6e163 | 333 | |
c72881e8 | 334 | /* Enable the clockwatch on ST Variants */ |
2f397216 | 335 | if (ldata->hw_designer == AMBA_VENDOR_ST) |
c72881e8 LW |
336 | writel(readl(ldata->base + RTC_CR) | RTC_CR_CWEN, |
337 | ldata->base + RTC_CR); | |
338 | ||
c0a5f4a0 RK |
339 | /* |
340 | * On ST PL031 variants, the RTC reset value does not provide correct | |
341 | * weekday for 2000-01-01. Correct the erroneous sunday to saturday. | |
342 | */ | |
343 | if (ldata->hw_designer == AMBA_VENDOR_ST) { | |
344 | if (readl(ldata->base + RTC_YDR) == 0x2000) { | |
345 | time = readl(ldata->base + RTC_DR); | |
346 | if ((time & | |
347 | (RTC_MON_MASK | RTC_MDAY_MASK | RTC_WDAY_MASK)) | |
348 | == 0x02120000) { | |
349 | time = time | (0x7 << RTC_WDAY_SHIFT); | |
350 | writel(0x2000, ldata->base + RTC_YLR); | |
351 | writel(time, ldata->base + RTC_LR); | |
352 | } | |
353 | } | |
354 | } | |
355 | ||
c72881e8 LW |
356 | ldata->rtc = rtc_device_register("pl031", &adev->dev, ops, |
357 | THIS_MODULE); | |
8ae6e163 DS |
358 | if (IS_ERR(ldata->rtc)) { |
359 | ret = PTR_ERR(ldata->rtc); | |
360 | goto out_no_rtc; | |
361 | } | |
362 | ||
c72881e8 | 363 | if (request_irq(adev->irq[0], pl031_interrupt, |
2f6e5f94 | 364 | 0, "rtc-pl031", ldata)) { |
c72881e8 LW |
365 | ret = -EIO; |
366 | goto out_no_irq; | |
367 | } | |
368 | ||
8ae6e163 DS |
369 | return 0; |
370 | ||
8ae6e163 | 371 | out_no_irq: |
c72881e8 LW |
372 | rtc_device_unregister(ldata->rtc); |
373 | out_no_rtc: | |
8ae6e163 | 374 | iounmap(ldata->base); |
2dba8518 | 375 | amba_set_drvdata(adev, NULL); |
8ae6e163 | 376 | out_no_remap: |
8ae6e163 DS |
377 | kfree(ldata); |
378 | out: | |
2dba8518 RK |
379 | amba_release_regions(adev); |
380 | err_req: | |
c72881e8 | 381 | |
8ae6e163 DS |
382 | return ret; |
383 | } | |
384 | ||
c72881e8 LW |
385 | /* Operations for the original ARM version */ |
386 | static struct rtc_class_ops arm_pl031_ops = { | |
387 | .read_time = pl031_read_time, | |
388 | .set_time = pl031_set_time, | |
389 | .read_alarm = pl031_read_alarm, | |
390 | .set_alarm = pl031_set_alarm, | |
391 | .alarm_irq_enable = pl031_alarm_irq_enable, | |
392 | }; | |
393 | ||
394 | /* The First ST derivative */ | |
395 | static struct rtc_class_ops stv1_pl031_ops = { | |
396 | .read_time = pl031_read_time, | |
397 | .set_time = pl031_set_time, | |
398 | .read_alarm = pl031_read_alarm, | |
399 | .set_alarm = pl031_set_alarm, | |
400 | .alarm_irq_enable = pl031_alarm_irq_enable, | |
c72881e8 LW |
401 | }; |
402 | ||
403 | /* And the second ST derivative */ | |
404 | static struct rtc_class_ops stv2_pl031_ops = { | |
405 | .read_time = pl031_stv2_read_time, | |
406 | .set_time = pl031_stv2_set_time, | |
407 | .read_alarm = pl031_stv2_read_alarm, | |
408 | .set_alarm = pl031_stv2_set_alarm, | |
409 | .alarm_irq_enable = pl031_alarm_irq_enable, | |
c72881e8 LW |
410 | }; |
411 | ||
2c39c9e1 | 412 | static struct amba_id pl031_ids[] = { |
8ae6e163 | 413 | { |
2934d6a8 LW |
414 | .id = 0x00041031, |
415 | .mask = 0x000fffff, | |
c72881e8 LW |
416 | .data = &arm_pl031_ops, |
417 | }, | |
418 | /* ST Micro variants */ | |
419 | { | |
420 | .id = 0x00180031, | |
421 | .mask = 0x00ffffff, | |
422 | .data = &stv1_pl031_ops, | |
423 | }, | |
424 | { | |
425 | .id = 0x00280031, | |
426 | .mask = 0x00ffffff, | |
427 | .data = &stv2_pl031_ops, | |
2934d6a8 | 428 | }, |
8ae6e163 DS |
429 | {0, 0}, |
430 | }; | |
431 | ||
f5feac2a DM |
432 | MODULE_DEVICE_TABLE(amba, pl031_ids); |
433 | ||
8ae6e163 DS |
434 | static struct amba_driver pl031_driver = { |
435 | .drv = { | |
436 | .name = "rtc-pl031", | |
437 | }, | |
438 | .id_table = pl031_ids, | |
439 | .probe = pl031_probe, | |
440 | .remove = pl031_remove, | |
441 | }; | |
442 | ||
9e5ed094 | 443 | module_amba_driver(pl031_driver); |
8ae6e163 DS |
444 | |
445 | MODULE_AUTHOR("Deepak Saxena <dsaxena@plexity.net"); | |
446 | MODULE_DESCRIPTION("ARM AMBA PL031 RTC Driver"); | |
447 | MODULE_LICENSE("GPL"); |