Commit | Line | Data |
---|---|---|
67905540 MR |
1 | /* |
2 | * Allwinner SoCs hstimer driver. | |
3 | * | |
4 | * Copyright (C) 2013 Maxime Ripard | |
5 | * | |
6 | * Maxime Ripard <maxime.ripard@free-electrons.com> | |
7 | * | |
8 | * This file is licensed under the terms of the GNU General Public | |
9 | * License version 2. This program is licensed "as is" without any | |
10 | * warranty of any kind, whether express or implied. | |
11 | */ | |
12 | ||
13 | #include <linux/clk.h> | |
14 | #include <linux/clockchips.h> | |
459fa246 | 15 | #include <linux/clocksource.h> |
67905540 MR |
16 | #include <linux/delay.h> |
17 | #include <linux/interrupt.h> | |
18 | #include <linux/irq.h> | |
19 | #include <linux/irqreturn.h> | |
e50a00be | 20 | #include <linux/reset.h> |
4a59058f | 21 | #include <linux/slab.h> |
67905540 MR |
22 | #include <linux/of.h> |
23 | #include <linux/of_address.h> | |
24 | #include <linux/of_irq.h> | |
25 | ||
26 | #define TIMER_IRQ_EN_REG 0x00 | |
27 | #define TIMER_IRQ_EN(val) BIT(val) | |
28 | #define TIMER_IRQ_ST_REG 0x04 | |
29 | #define TIMER_CTL_REG(val) (0x20 * (val) + 0x10) | |
30 | #define TIMER_CTL_ENABLE BIT(0) | |
31 | #define TIMER_CTL_RELOAD BIT(1) | |
32 | #define TIMER_CTL_CLK_PRES(val) (((val) & 0x7) << 4) | |
33 | #define TIMER_CTL_ONESHOT BIT(7) | |
34 | #define TIMER_INTVAL_LO_REG(val) (0x20 * (val) + 0x14) | |
35 | #define TIMER_INTVAL_HI_REG(val) (0x20 * (val) + 0x18) | |
36 | #define TIMER_CNTVAL_LO_REG(val) (0x20 * (val) + 0x1c) | |
37 | #define TIMER_CNTVAL_HI_REG(val) (0x20 * (val) + 0x20) | |
38 | ||
39 | #define TIMER_SYNC_TICKS 3 | |
40 | ||
4a59058f MR |
41 | struct sun5i_timer { |
42 | void __iomem *base; | |
43 | struct clk *clk; | |
3071efa4 | 44 | struct notifier_block clk_rate_cb; |
4a59058f MR |
45 | u32 ticks_per_jiffy; |
46 | }; | |
47 | ||
3071efa4 MR |
48 | #define to_sun5i_timer(x) \ |
49 | container_of(x, struct sun5i_timer, clk_rate_cb) | |
50 | ||
4a59058f MR |
51 | struct sun5i_timer_clksrc { |
52 | struct sun5i_timer timer; | |
53 | struct clocksource clksrc; | |
54 | }; | |
55 | ||
56 | #define to_sun5i_timer_clksrc(x) \ | |
57 | container_of(x, struct sun5i_timer_clksrc, clksrc) | |
58 | ||
59 | struct sun5i_timer_clkevt { | |
60 | struct sun5i_timer timer; | |
61 | struct clock_event_device clkevt; | |
62 | }; | |
63 | ||
64 | #define to_sun5i_timer_clkevt(x) \ | |
65 | container_of(x, struct sun5i_timer_clkevt, clkevt) | |
67905540 MR |
66 | |
67 | /* | |
68 | * When we disable a timer, we need to wait at least for 2 cycles of | |
69 | * the timer source clock. We will use for that the clocksource timer | |
70 | * that is already setup and runs at the same frequency than the other | |
71 | * timers, and we never will be disabled. | |
72 | */ | |
4a59058f | 73 | static void sun5i_clkevt_sync(struct sun5i_timer_clkevt *ce) |
67905540 | 74 | { |
4a59058f | 75 | u32 old = readl(ce->timer.base + TIMER_CNTVAL_LO_REG(1)); |
67905540 | 76 | |
4a59058f | 77 | while ((old - readl(ce->timer.base + TIMER_CNTVAL_LO_REG(1))) < TIMER_SYNC_TICKS) |
67905540 MR |
78 | cpu_relax(); |
79 | } | |
80 | ||
4a59058f | 81 | static void sun5i_clkevt_time_stop(struct sun5i_timer_clkevt *ce, u8 timer) |
67905540 | 82 | { |
4a59058f MR |
83 | u32 val = readl(ce->timer.base + TIMER_CTL_REG(timer)); |
84 | writel(val & ~TIMER_CTL_ENABLE, ce->timer.base + TIMER_CTL_REG(timer)); | |
67905540 | 85 | |
4a59058f | 86 | sun5i_clkevt_sync(ce); |
67905540 MR |
87 | } |
88 | ||
4a59058f | 89 | static void sun5i_clkevt_time_setup(struct sun5i_timer_clkevt *ce, u8 timer, u32 delay) |
67905540 | 90 | { |
4a59058f | 91 | writel(delay, ce->timer.base + TIMER_INTVAL_LO_REG(timer)); |
67905540 MR |
92 | } |
93 | ||
4a59058f | 94 | static void sun5i_clkevt_time_start(struct sun5i_timer_clkevt *ce, u8 timer, bool periodic) |
67905540 | 95 | { |
4a59058f | 96 | u32 val = readl(ce->timer.base + TIMER_CTL_REG(timer)); |
67905540 MR |
97 | |
98 | if (periodic) | |
99 | val &= ~TIMER_CTL_ONESHOT; | |
100 | else | |
101 | val |= TIMER_CTL_ONESHOT; | |
102 | ||
103 | writel(val | TIMER_CTL_ENABLE | TIMER_CTL_RELOAD, | |
4a59058f | 104 | ce->timer.base + TIMER_CTL_REG(timer)); |
67905540 MR |
105 | } |
106 | ||
7486f5ad | 107 | static int sun5i_clkevt_shutdown(struct clock_event_device *clkevt) |
67905540 | 108 | { |
4a59058f MR |
109 | struct sun5i_timer_clkevt *ce = to_sun5i_timer_clkevt(clkevt); |
110 | ||
7486f5ad VK |
111 | sun5i_clkevt_time_stop(ce, 0); |
112 | return 0; | |
113 | } | |
114 | ||
115 | static int sun5i_clkevt_set_oneshot(struct clock_event_device *clkevt) | |
116 | { | |
117 | struct sun5i_timer_clkevt *ce = to_sun5i_timer_clkevt(clkevt); | |
118 | ||
119 | sun5i_clkevt_time_stop(ce, 0); | |
120 | sun5i_clkevt_time_start(ce, 0, false); | |
121 | return 0; | |
122 | } | |
123 | ||
124 | static int sun5i_clkevt_set_periodic(struct clock_event_device *clkevt) | |
125 | { | |
126 | struct sun5i_timer_clkevt *ce = to_sun5i_timer_clkevt(clkevt); | |
127 | ||
128 | sun5i_clkevt_time_stop(ce, 0); | |
129 | sun5i_clkevt_time_setup(ce, 0, ce->timer.ticks_per_jiffy); | |
130 | sun5i_clkevt_time_start(ce, 0, true); | |
131 | return 0; | |
67905540 MR |
132 | } |
133 | ||
134 | static int sun5i_clkevt_next_event(unsigned long evt, | |
4a59058f | 135 | struct clock_event_device *clkevt) |
67905540 | 136 | { |
4a59058f MR |
137 | struct sun5i_timer_clkevt *ce = to_sun5i_timer_clkevt(clkevt); |
138 | ||
139 | sun5i_clkevt_time_stop(ce, 0); | |
140 | sun5i_clkevt_time_setup(ce, 0, evt - TIMER_SYNC_TICKS); | |
141 | sun5i_clkevt_time_start(ce, 0, false); | |
67905540 MR |
142 | |
143 | return 0; | |
144 | } | |
145 | ||
67905540 MR |
146 | static irqreturn_t sun5i_timer_interrupt(int irq, void *dev_id) |
147 | { | |
4a59058f | 148 | struct sun5i_timer_clkevt *ce = (struct sun5i_timer_clkevt *)dev_id; |
67905540 | 149 | |
4a59058f MR |
150 | writel(0x1, ce->timer.base + TIMER_IRQ_ST_REG); |
151 | ce->clkevt.event_handler(&ce->clkevt); | |
67905540 MR |
152 | |
153 | return IRQ_HANDLED; | |
154 | } | |
155 | ||
a5a1d1c2 | 156 | static u64 sun5i_clksrc_read(struct clocksource *clksrc) |
59387683 CYT |
157 | { |
158 | struct sun5i_timer_clksrc *cs = to_sun5i_timer_clksrc(clksrc); | |
159 | ||
160 | return ~readl(cs->timer.base + TIMER_CNTVAL_LO_REG(1)); | |
161 | } | |
162 | ||
3071efa4 MR |
163 | static int sun5i_rate_cb_clksrc(struct notifier_block *nb, |
164 | unsigned long event, void *data) | |
165 | { | |
166 | struct clk_notifier_data *ndata = data; | |
167 | struct sun5i_timer *timer = to_sun5i_timer(nb); | |
168 | struct sun5i_timer_clksrc *cs = container_of(timer, struct sun5i_timer_clksrc, timer); | |
169 | ||
170 | switch (event) { | |
171 | case PRE_RATE_CHANGE: | |
172 | clocksource_unregister(&cs->clksrc); | |
173 | break; | |
174 | ||
175 | case POST_RATE_CHANGE: | |
176 | clocksource_register_hz(&cs->clksrc, ndata->new_rate); | |
177 | break; | |
178 | ||
179 | default: | |
180 | break; | |
181 | } | |
182 | ||
183 | return NOTIFY_DONE; | |
184 | } | |
185 | ||
4a59058f MR |
186 | static int __init sun5i_setup_clocksource(struct device_node *node, |
187 | void __iomem *base, | |
188 | struct clk *clk, int irq) | |
189 | { | |
190 | struct sun5i_timer_clksrc *cs; | |
191 | unsigned long rate; | |
192 | int ret; | |
193 | ||
194 | cs = kzalloc(sizeof(*cs), GFP_KERNEL); | |
195 | if (!cs) | |
196 | return -ENOMEM; | |
197 | ||
198 | ret = clk_prepare_enable(clk); | |
199 | if (ret) { | |
200 | pr_err("Couldn't enable parent clock\n"); | |
201 | goto err_free; | |
202 | } | |
203 | ||
204 | rate = clk_get_rate(clk); | |
e7e7e0d7 CYT |
205 | if (!rate) { |
206 | pr_err("Couldn't get parent clock rate\n"); | |
207 | ret = -EINVAL; | |
208 | goto err_disable_clk; | |
209 | } | |
4a59058f MR |
210 | |
211 | cs->timer.base = base; | |
212 | cs->timer.clk = clk; | |
3071efa4 MR |
213 | cs->timer.clk_rate_cb.notifier_call = sun5i_rate_cb_clksrc; |
214 | cs->timer.clk_rate_cb.next = NULL; | |
215 | ||
216 | ret = clk_notifier_register(clk, &cs->timer.clk_rate_cb); | |
217 | if (ret) { | |
218 | pr_err("Unable to register clock notifier.\n"); | |
219 | goto err_disable_clk; | |
220 | } | |
4a59058f MR |
221 | |
222 | writel(~0, base + TIMER_INTVAL_LO_REG(1)); | |
223 | writel(TIMER_CTL_ENABLE | TIMER_CTL_RELOAD, | |
224 | base + TIMER_CTL_REG(1)); | |
225 | ||
59387683 CYT |
226 | cs->clksrc.name = node->name; |
227 | cs->clksrc.rating = 340; | |
228 | cs->clksrc.read = sun5i_clksrc_read; | |
229 | cs->clksrc.mask = CLOCKSOURCE_MASK(32); | |
230 | cs->clksrc.flags = CLOCK_SOURCE_IS_CONTINUOUS; | |
231 | ||
232 | ret = clocksource_register_hz(&cs->clksrc, rate); | |
4a59058f MR |
233 | if (ret) { |
234 | pr_err("Couldn't register clock source.\n"); | |
3071efa4 | 235 | goto err_remove_notifier; |
4a59058f MR |
236 | } |
237 | ||
238 | return 0; | |
239 | ||
3071efa4 MR |
240 | err_remove_notifier: |
241 | clk_notifier_unregister(clk, &cs->timer.clk_rate_cb); | |
4a59058f MR |
242 | err_disable_clk: |
243 | clk_disable_unprepare(clk); | |
244 | err_free: | |
245 | kfree(cs); | |
246 | return ret; | |
247 | } | |
248 | ||
3071efa4 MR |
249 | static int sun5i_rate_cb_clkevt(struct notifier_block *nb, |
250 | unsigned long event, void *data) | |
251 | { | |
252 | struct clk_notifier_data *ndata = data; | |
253 | struct sun5i_timer *timer = to_sun5i_timer(nb); | |
254 | struct sun5i_timer_clkevt *ce = container_of(timer, struct sun5i_timer_clkevt, timer); | |
255 | ||
256 | if (event == POST_RATE_CHANGE) { | |
257 | clockevents_update_freq(&ce->clkevt, ndata->new_rate); | |
258 | ce->timer.ticks_per_jiffy = DIV_ROUND_UP(ndata->new_rate, HZ); | |
259 | } | |
260 | ||
261 | return NOTIFY_DONE; | |
262 | } | |
263 | ||
4a59058f MR |
264 | static int __init sun5i_setup_clockevent(struct device_node *node, void __iomem *base, |
265 | struct clk *clk, int irq) | |
266 | { | |
267 | struct sun5i_timer_clkevt *ce; | |
268 | unsigned long rate; | |
269 | int ret; | |
270 | u32 val; | |
271 | ||
272 | ce = kzalloc(sizeof(*ce), GFP_KERNEL); | |
273 | if (!ce) | |
274 | return -ENOMEM; | |
275 | ||
276 | ret = clk_prepare_enable(clk); | |
277 | if (ret) { | |
278 | pr_err("Couldn't enable parent clock\n"); | |
279 | goto err_free; | |
280 | } | |
281 | ||
282 | rate = clk_get_rate(clk); | |
e7e7e0d7 CYT |
283 | if (!rate) { |
284 | pr_err("Couldn't get parent clock rate\n"); | |
285 | ret = -EINVAL; | |
286 | goto err_disable_clk; | |
287 | } | |
4a59058f MR |
288 | |
289 | ce->timer.base = base; | |
290 | ce->timer.ticks_per_jiffy = DIV_ROUND_UP(rate, HZ); | |
291 | ce->timer.clk = clk; | |
3071efa4 MR |
292 | ce->timer.clk_rate_cb.notifier_call = sun5i_rate_cb_clkevt; |
293 | ce->timer.clk_rate_cb.next = NULL; | |
294 | ||
295 | ret = clk_notifier_register(clk, &ce->timer.clk_rate_cb); | |
296 | if (ret) { | |
297 | pr_err("Unable to register clock notifier.\n"); | |
298 | goto err_disable_clk; | |
299 | } | |
4a59058f MR |
300 | |
301 | ce->clkevt.name = node->name; | |
302 | ce->clkevt.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT; | |
303 | ce->clkevt.set_next_event = sun5i_clkevt_next_event; | |
7486f5ad VK |
304 | ce->clkevt.set_state_shutdown = sun5i_clkevt_shutdown; |
305 | ce->clkevt.set_state_periodic = sun5i_clkevt_set_periodic; | |
306 | ce->clkevt.set_state_oneshot = sun5i_clkevt_set_oneshot; | |
307 | ce->clkevt.tick_resume = sun5i_clkevt_shutdown; | |
4a59058f MR |
308 | ce->clkevt.rating = 340; |
309 | ce->clkevt.irq = irq; | |
310 | ce->clkevt.cpumask = cpu_possible_mask; | |
311 | ||
312 | /* Enable timer0 interrupt */ | |
313 | val = readl(base + TIMER_IRQ_EN_REG); | |
314 | writel(val | TIMER_IRQ_EN(0), base + TIMER_IRQ_EN_REG); | |
315 | ||
316 | clockevents_config_and_register(&ce->clkevt, rate, | |
317 | TIMER_SYNC_TICKS, 0xffffffff); | |
318 | ||
319 | ret = request_irq(irq, sun5i_timer_interrupt, IRQF_TIMER | IRQF_IRQPOLL, | |
320 | "sun5i_timer0", ce); | |
321 | if (ret) { | |
322 | pr_err("Unable to register interrupt\n"); | |
3071efa4 | 323 | goto err_remove_notifier; |
4a59058f MR |
324 | } |
325 | ||
326 | return 0; | |
327 | ||
3071efa4 MR |
328 | err_remove_notifier: |
329 | clk_notifier_unregister(clk, &ce->timer.clk_rate_cb); | |
4a59058f MR |
330 | err_disable_clk: |
331 | clk_disable_unprepare(clk); | |
332 | err_free: | |
333 | kfree(ce); | |
334 | return ret; | |
335 | } | |
336 | ||
e4d9f2ee | 337 | static int __init sun5i_timer_init(struct device_node *node) |
67905540 | 338 | { |
e50a00be | 339 | struct reset_control *rstc; |
4a59058f | 340 | void __iomem *timer_base; |
67905540 | 341 | struct clk *clk; |
e4d9f2ee | 342 | int irq, ret; |
67905540 | 343 | |
a45860d0 | 344 | timer_base = of_io_request_and_map(node, 0, of_node_full_name(node)); |
e4d9f2ee | 345 | if (IS_ERR(timer_base)) { |
ac9ce6d1 | 346 | pr_err("Can't map registers\n"); |
ed7158ba | 347 | return PTR_ERR(timer_base); |
e4d9f2ee | 348 | } |
67905540 MR |
349 | |
350 | irq = irq_of_parse_and_map(node, 0); | |
e4d9f2ee | 351 | if (irq <= 0) { |
ac9ce6d1 | 352 | pr_err("Can't parse IRQ\n"); |
e4d9f2ee DL |
353 | return -EINVAL; |
354 | } | |
67905540 MR |
355 | |
356 | clk = of_clk_get(node, 0); | |
e4d9f2ee | 357 | if (IS_ERR(clk)) { |
ac9ce6d1 | 358 | pr_err("Can't get timer clock\n"); |
e4d9f2ee DL |
359 | return PTR_ERR(clk); |
360 | } | |
67905540 | 361 | |
e50a00be MR |
362 | rstc = of_reset_control_get(node, NULL); |
363 | if (!IS_ERR(rstc)) | |
364 | reset_control_deassert(rstc); | |
365 | ||
e4d9f2ee DL |
366 | ret = sun5i_setup_clocksource(node, timer_base, clk, irq); |
367 | if (ret) | |
368 | return ret; | |
369 | ||
370 | return sun5i_setup_clockevent(node, timer_base, clk, irq); | |
67905540 | 371 | } |
17273395 | 372 | TIMER_OF_DECLARE(sun5i_a13, "allwinner,sun5i-a13-hstimer", |
e4d9f2ee | 373 | sun5i_timer_init); |
17273395 | 374 | TIMER_OF_DECLARE(sun7i_a20, "allwinner,sun7i-a20-hstimer", |
e4d9f2ee | 375 | sun5i_timer_init); |