1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * Driver for the RTC in Marvell SoCs. |
4 | */ |
5 | |
6 | #include <linux/init.h> |
7 | #include <linux/kernel.h> |
8 | #include <linux/rtc.h> |
9 | #include <linux/bcd.h> |
10 | #include <linux/bitops.h> |
11 | #include <linux/io.h> |
12 | #include <linux/platform_device.h> |
13 | #include <linux/of.h> |
14 | #include <linux/delay.h> |
15 | #include <linux/clk.h> |
16 | #include <linux/gfp.h> |
17 | #include <linux/module.h> |
18 | |
19 | |
20 | #define RTC_TIME_REG_OFFS 0 |
21 | #define RTC_SECONDS_OFFS 0 |
22 | #define RTC_MINUTES_OFFS 8 |
23 | #define RTC_HOURS_OFFS 16 |
24 | #define RTC_WDAY_OFFS 24 |
25 | #define RTC_HOURS_12H_MODE BIT(22) /* 12 hour mode */ |
26 | |
27 | #define RTC_DATE_REG_OFFS 4 |
28 | #define RTC_MDAY_OFFS 0 |
29 | #define RTC_MONTH_OFFS 8 |
30 | #define RTC_YEAR_OFFS 16 |
31 | |
32 | #define RTC_ALARM_TIME_REG_OFFS 8 |
33 | #define RTC_ALARM_DATE_REG_OFFS 0xc |
34 | #define RTC_ALARM_VALID BIT(7) |
35 | |
36 | #define RTC_ALARM_INTERRUPT_MASK_REG_OFFS 0x10 |
37 | #define RTC_ALARM_INTERRUPT_CASUE_REG_OFFS 0x14 |
38 | |
39 | struct rtc_plat_data { |
40 | struct rtc_device *rtc; |
41 | void __iomem *ioaddr; |
42 | int irq; |
43 | struct clk *clk; |
44 | }; |
45 | |
46 | static int mv_rtc_set_time(struct device *dev, struct rtc_time *tm) |
47 | { |
48 | struct rtc_plat_data *pdata = dev_get_drvdata(dev); |
49 | void __iomem *ioaddr = pdata->ioaddr; |
50 | u32 rtc_reg; |
51 | |
52 | rtc_reg = (bin2bcd(tm->tm_sec) << RTC_SECONDS_OFFS) | |
53 | (bin2bcd(tm->tm_min) << RTC_MINUTES_OFFS) | |
54 | (bin2bcd(tm->tm_hour) << RTC_HOURS_OFFS) | |
55 | (bin2bcd(tm->tm_wday) << RTC_WDAY_OFFS); |
56 | writel(val: rtc_reg, addr: ioaddr + RTC_TIME_REG_OFFS); |
57 | |
58 | rtc_reg = (bin2bcd(tm->tm_mday) << RTC_MDAY_OFFS) | |
59 | (bin2bcd(tm->tm_mon + 1) << RTC_MONTH_OFFS) | |
60 | (bin2bcd(tm->tm_year - 100) << RTC_YEAR_OFFS); |
61 | writel(val: rtc_reg, addr: ioaddr + RTC_DATE_REG_OFFS); |
62 | |
63 | return 0; |
64 | } |
65 | |
66 | static int mv_rtc_read_time(struct device *dev, struct rtc_time *tm) |
67 | { |
68 | struct rtc_plat_data *pdata = dev_get_drvdata(dev); |
69 | void __iomem *ioaddr = pdata->ioaddr; |
70 | u32 rtc_time, rtc_date; |
71 | unsigned int year, month, day, hour, minute, second, wday; |
72 | |
73 | rtc_time = readl(addr: ioaddr + RTC_TIME_REG_OFFS); |
74 | rtc_date = readl(addr: ioaddr + RTC_DATE_REG_OFFS); |
75 | |
76 | second = rtc_time & 0x7f; |
77 | minute = (rtc_time >> RTC_MINUTES_OFFS) & 0x7f; |
78 | hour = (rtc_time >> RTC_HOURS_OFFS) & 0x3f; /* assume 24 hour mode */ |
79 | wday = (rtc_time >> RTC_WDAY_OFFS) & 0x7; |
80 | |
81 | day = rtc_date & 0x3f; |
82 | month = (rtc_date >> RTC_MONTH_OFFS) & 0x3f; |
83 | year = (rtc_date >> RTC_YEAR_OFFS) & 0xff; |
84 | |
85 | tm->tm_sec = bcd2bin(second); |
86 | tm->tm_min = bcd2bin(minute); |
87 | tm->tm_hour = bcd2bin(hour); |
88 | tm->tm_mday = bcd2bin(day); |
89 | tm->tm_wday = bcd2bin(wday); |
90 | tm->tm_mon = bcd2bin(month) - 1; |
91 | /* hw counts from year 2000, but tm_year is relative to 1900 */ |
92 | tm->tm_year = bcd2bin(year) + 100; |
93 | |
94 | return 0; |
95 | } |
96 | |
97 | static int mv_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alm) |
98 | { |
99 | struct rtc_plat_data *pdata = dev_get_drvdata(dev); |
100 | void __iomem *ioaddr = pdata->ioaddr; |
101 | u32 rtc_time, rtc_date; |
102 | unsigned int year, month, day, hour, minute, second, wday; |
103 | |
104 | rtc_time = readl(addr: ioaddr + RTC_ALARM_TIME_REG_OFFS); |
105 | rtc_date = readl(addr: ioaddr + RTC_ALARM_DATE_REG_OFFS); |
106 | |
107 | second = rtc_time & 0x7f; |
108 | minute = (rtc_time >> RTC_MINUTES_OFFS) & 0x7f; |
109 | hour = (rtc_time >> RTC_HOURS_OFFS) & 0x3f; /* assume 24 hour mode */ |
110 | wday = (rtc_time >> RTC_WDAY_OFFS) & 0x7; |
111 | |
112 | day = rtc_date & 0x3f; |
113 | month = (rtc_date >> RTC_MONTH_OFFS) & 0x3f; |
114 | year = (rtc_date >> RTC_YEAR_OFFS) & 0xff; |
115 | |
116 | alm->time.tm_sec = bcd2bin(second); |
117 | alm->time.tm_min = bcd2bin(minute); |
118 | alm->time.tm_hour = bcd2bin(hour); |
119 | alm->time.tm_mday = bcd2bin(day); |
120 | alm->time.tm_wday = bcd2bin(wday); |
121 | alm->time.tm_mon = bcd2bin(month) - 1; |
122 | /* hw counts from year 2000, but tm_year is relative to 1900 */ |
123 | alm->time.tm_year = bcd2bin(year) + 100; |
124 | |
125 | alm->enabled = !!readl(addr: ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); |
126 | |
127 | return rtc_valid_tm(tm: &alm->time); |
128 | } |
129 | |
130 | static int mv_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alm) |
131 | { |
132 | struct rtc_plat_data *pdata = dev_get_drvdata(dev); |
133 | void __iomem *ioaddr = pdata->ioaddr; |
134 | u32 rtc_reg = 0; |
135 | |
136 | if (alm->time.tm_sec >= 0) |
137 | rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_sec)) |
138 | << RTC_SECONDS_OFFS; |
139 | if (alm->time.tm_min >= 0) |
140 | rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_min)) |
141 | << RTC_MINUTES_OFFS; |
142 | if (alm->time.tm_hour >= 0) |
143 | rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_hour)) |
144 | << RTC_HOURS_OFFS; |
145 | |
146 | writel(val: rtc_reg, addr: ioaddr + RTC_ALARM_TIME_REG_OFFS); |
147 | |
148 | if (alm->time.tm_mday >= 0) |
149 | rtc_reg = (RTC_ALARM_VALID | bin2bcd(alm->time.tm_mday)) |
150 | << RTC_MDAY_OFFS; |
151 | else |
152 | rtc_reg = 0; |
153 | |
154 | if (alm->time.tm_mon >= 0) |
155 | rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_mon + 1)) |
156 | << RTC_MONTH_OFFS; |
157 | |
158 | if (alm->time.tm_year >= 0) |
159 | rtc_reg |= (RTC_ALARM_VALID | bin2bcd(alm->time.tm_year - 100)) |
160 | << RTC_YEAR_OFFS; |
161 | |
162 | writel(val: rtc_reg, addr: ioaddr + RTC_ALARM_DATE_REG_OFFS); |
163 | writel(val: 0, addr: ioaddr + RTC_ALARM_INTERRUPT_CASUE_REG_OFFS); |
164 | writel(val: alm->enabled ? 1 : 0, |
165 | addr: ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); |
166 | |
167 | return 0; |
168 | } |
169 | |
170 | static int mv_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) |
171 | { |
172 | struct rtc_plat_data *pdata = dev_get_drvdata(dev); |
173 | void __iomem *ioaddr = pdata->ioaddr; |
174 | |
175 | if (pdata->irq < 0) |
176 | return -EINVAL; /* fall back into rtc-dev's emulation */ |
177 | |
178 | if (enabled) |
179 | writel(val: 1, addr: ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); |
180 | else |
181 | writel(val: 0, addr: ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); |
182 | return 0; |
183 | } |
184 | |
185 | static irqreturn_t mv_rtc_interrupt(int irq, void *data) |
186 | { |
187 | struct rtc_plat_data *pdata = data; |
188 | void __iomem *ioaddr = pdata->ioaddr; |
189 | |
190 | /* alarm irq? */ |
191 | if (!readl(addr: ioaddr + RTC_ALARM_INTERRUPT_CASUE_REG_OFFS)) |
192 | return IRQ_NONE; |
193 | |
194 | /* clear interrupt */ |
195 | writel(val: 0, addr: ioaddr + RTC_ALARM_INTERRUPT_CASUE_REG_OFFS); |
196 | rtc_update_irq(rtc: pdata->rtc, num: 1, RTC_IRQF | RTC_AF); |
197 | return IRQ_HANDLED; |
198 | } |
199 | |
200 | static const struct rtc_class_ops mv_rtc_ops = { |
201 | .read_time = mv_rtc_read_time, |
202 | .set_time = mv_rtc_set_time, |
203 | .read_alarm = mv_rtc_read_alarm, |
204 | .set_alarm = mv_rtc_set_alarm, |
205 | .alarm_irq_enable = mv_rtc_alarm_irq_enable, |
206 | }; |
207 | |
208 | static int __init mv_rtc_probe(struct platform_device *pdev) |
209 | { |
210 | struct rtc_plat_data *pdata; |
211 | u32 rtc_time; |
212 | int ret = 0; |
213 | |
214 | pdata = devm_kzalloc(dev: &pdev->dev, size: sizeof(*pdata), GFP_KERNEL); |
215 | if (!pdata) |
216 | return -ENOMEM; |
217 | |
218 | pdata->ioaddr = devm_platform_ioremap_resource(pdev, index: 0); |
219 | if (IS_ERR(ptr: pdata->ioaddr)) |
220 | return PTR_ERR(ptr: pdata->ioaddr); |
221 | |
222 | pdata->clk = devm_clk_get(dev: &pdev->dev, NULL); |
223 | /* Not all SoCs require a clock.*/ |
224 | if (!IS_ERR(ptr: pdata->clk)) |
225 | clk_prepare_enable(clk: pdata->clk); |
226 | |
227 | /* make sure the 24 hour mode is enabled */ |
228 | rtc_time = readl(addr: pdata->ioaddr + RTC_TIME_REG_OFFS); |
229 | if (rtc_time & RTC_HOURS_12H_MODE) { |
230 | dev_err(&pdev->dev, "12 Hour mode is enabled but not supported.\n" ); |
231 | ret = -EINVAL; |
232 | goto out; |
233 | } |
234 | |
235 | /* make sure it is actually functional */ |
236 | if (rtc_time == 0x01000000) { |
237 | ssleep(seconds: 1); |
238 | rtc_time = readl(addr: pdata->ioaddr + RTC_TIME_REG_OFFS); |
239 | if (rtc_time == 0x01000000) { |
240 | dev_err(&pdev->dev, "internal RTC not ticking\n" ); |
241 | ret = -ENODEV; |
242 | goto out; |
243 | } |
244 | } |
245 | |
246 | pdata->irq = platform_get_irq(pdev, 0); |
247 | |
248 | platform_set_drvdata(pdev, data: pdata); |
249 | |
250 | pdata->rtc = devm_rtc_allocate_device(dev: &pdev->dev); |
251 | if (IS_ERR(ptr: pdata->rtc)) { |
252 | ret = PTR_ERR(ptr: pdata->rtc); |
253 | goto out; |
254 | } |
255 | |
256 | if (pdata->irq >= 0) { |
257 | writel(val: 0, addr: pdata->ioaddr + RTC_ALARM_INTERRUPT_MASK_REG_OFFS); |
258 | if (devm_request_irq(dev: &pdev->dev, irq: pdata->irq, handler: mv_rtc_interrupt, |
259 | IRQF_SHARED, |
260 | devname: pdev->name, dev_id: pdata) < 0) { |
261 | dev_warn(&pdev->dev, "interrupt not available.\n" ); |
262 | pdata->irq = -1; |
263 | } |
264 | } |
265 | |
266 | if (pdata->irq >= 0) |
267 | device_init_wakeup(dev: &pdev->dev, enable: 1); |
268 | else |
269 | clear_bit(RTC_FEATURE_ALARM, addr: pdata->rtc->features); |
270 | |
271 | pdata->rtc->ops = &mv_rtc_ops; |
272 | pdata->rtc->range_min = RTC_TIMESTAMP_BEGIN_2000; |
273 | pdata->rtc->range_max = RTC_TIMESTAMP_END_2099; |
274 | |
275 | ret = devm_rtc_register_device(pdata->rtc); |
276 | if (!ret) |
277 | return 0; |
278 | out: |
279 | if (!IS_ERR(ptr: pdata->clk)) |
280 | clk_disable_unprepare(clk: pdata->clk); |
281 | |
282 | return ret; |
283 | } |
284 | |
285 | static void __exit mv_rtc_remove(struct platform_device *pdev) |
286 | { |
287 | struct rtc_plat_data *pdata = platform_get_drvdata(pdev); |
288 | |
289 | if (pdata->irq >= 0) |
290 | device_init_wakeup(dev: &pdev->dev, enable: 0); |
291 | |
292 | if (!IS_ERR(ptr: pdata->clk)) |
293 | clk_disable_unprepare(clk: pdata->clk); |
294 | } |
295 | |
296 | #ifdef CONFIG_OF |
297 | static const struct of_device_id rtc_mv_of_match_table[] = { |
298 | { .compatible = "marvell,orion-rtc" , }, |
299 | {} |
300 | }; |
301 | MODULE_DEVICE_TABLE(of, rtc_mv_of_match_table); |
302 | #endif |
303 | |
304 | /* |
305 | * mv_rtc_remove() lives in .exit.text. For drivers registered via |
306 | * module_platform_driver_probe() this is ok because they cannot get unbound at |
307 | * runtime. So mark the driver struct with __refdata to prevent modpost |
308 | * triggering a section mismatch warning. |
309 | */ |
310 | static struct platform_driver mv_rtc_driver __refdata = { |
311 | .remove_new = __exit_p(mv_rtc_remove), |
312 | .driver = { |
313 | .name = "rtc-mv" , |
314 | .of_match_table = of_match_ptr(rtc_mv_of_match_table), |
315 | }, |
316 | }; |
317 | |
318 | module_platform_driver_probe(mv_rtc_driver, mv_rtc_probe); |
319 | |
320 | MODULE_AUTHOR("Saeed Bishara <saeed@marvell.com>" ); |
321 | MODULE_DESCRIPTION("Marvell RTC driver" ); |
322 | MODULE_LICENSE("GPL" ); |
323 | MODULE_ALIAS("platform:rtc-mv" ); |
324 | |