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11#include <linux/kernel.h>
12#include <linux/init.h>
13#include <linux/types.h>
14#include <linux/interrupt.h>
15#include <linux/clocksource.h>
16#include <linux/clockchips.h>
17#include <linux/spinlock.h>
18#include <linux/io.h>
19#include <linux/clk.h>
20#include <linux/err.h>
21#include <linux/device.h>
22#include <linux/platform_device.h>
23
24#include <mach/hardware.h>
25#include <asm/system.h>
26#include <asm/irq.h>
27#include <asm/mach/irq.h>
28#include <asm/mach/time.h>
29#include <asm/errno.h>
30#include <mach/io.h>
31#include <mach/cputype.h>
32#include <mach/time.h>
33#include "clock.h"
34
35static struct clock_event_device clockevent_davinci;
36static unsigned int davinci_clock_tick_rate;
37
38
39
40
41
42
43enum {
44 TID_CLOCKEVENT,
45 TID_CLOCKSOURCE,
46};
47
48
49#define PID12 0x0
50#define TIM12 0x10
51#define TIM34 0x14
52#define PRD12 0x18
53#define PRD34 0x1c
54#define TCR 0x20
55#define TGCR 0x24
56#define WDTCR 0x28
57
58
59#define CMP12_0 0x60
60#define CMP12_1 0x64
61#define CMP12_2 0x68
62#define CMP12_3 0x6c
63#define CMP12_4 0x70
64#define CMP12_5 0x74
65#define CMP12_6 0x78
66#define CMP12_7 0x7c
67
68
69#define TCR_ENAMODE_DISABLE 0x0
70#define TCR_ENAMODE_ONESHOT 0x1
71#define TCR_ENAMODE_PERIODIC 0x2
72#define TCR_ENAMODE_MASK 0x3
73
74#define TGCR_TIMMODE_SHIFT 2
75#define TGCR_TIMMODE_64BIT_GP 0x0
76#define TGCR_TIMMODE_32BIT_UNCHAINED 0x1
77#define TGCR_TIMMODE_64BIT_WDOG 0x2
78#define TGCR_TIMMODE_32BIT_CHAINED 0x3
79
80#define TGCR_TIM12RS_SHIFT 0
81#define TGCR_TIM34RS_SHIFT 1
82#define TGCR_RESET 0x0
83#define TGCR_UNRESET 0x1
84#define TGCR_RESET_MASK 0x3
85
86#define WDTCR_WDEN_SHIFT 14
87#define WDTCR_WDEN_DISABLE 0x0
88#define WDTCR_WDEN_ENABLE 0x1
89#define WDTCR_WDKEY_SHIFT 16
90#define WDTCR_WDKEY_SEQ0 0xa5c6
91#define WDTCR_WDKEY_SEQ1 0xda7e
92
93struct timer_s {
94 char *name;
95 unsigned int id;
96 unsigned long period;
97 unsigned long opts;
98 unsigned long flags;
99 void __iomem *base;
100 unsigned long tim_off;
101 unsigned long prd_off;
102 unsigned long enamode_shift;
103 struct irqaction irqaction;
104};
105static struct timer_s timers[];
106
107
108#define TIMER_OPTS_DISABLED 0x01
109#define TIMER_OPTS_ONESHOT 0x02
110#define TIMER_OPTS_PERIODIC 0x04
111#define TIMER_OPTS_STATE_MASK 0x07
112
113#define TIMER_OPTS_USE_COMPARE 0x80000000
114#define USING_COMPARE(t) ((t)->opts & TIMER_OPTS_USE_COMPARE)
115
116static char *id_to_name[] = {
117 [T0_BOT] = "timer0_0",
118 [T0_TOP] = "timer0_1",
119 [T1_BOT] = "timer1_0",
120 [T1_TOP] = "timer1_1",
121};
122
123static int timer32_config(struct timer_s *t)
124{
125 u32 tcr;
126 struct davinci_soc_info *soc_info = &davinci_soc_info;
127
128 if (USING_COMPARE(t)) {
129 struct davinci_timer_instance *dtip =
130 soc_info->timer_info->timers;
131 int event_timer = ID_TO_TIMER(timers[TID_CLOCKEVENT].id);
132
133
134
135
136
137
138
139 __raw_writel(__raw_readl(t->base + t->tim_off) + t->period,
140 t->base + dtip[event_timer].cmp_off);
141 } else {
142 tcr = __raw_readl(t->base + TCR);
143
144
145 tcr &= ~(TCR_ENAMODE_MASK << t->enamode_shift);
146 __raw_writel(tcr, t->base + TCR);
147
148
149 __raw_writel(0, t->base + t->tim_off);
150 __raw_writel(t->period, t->base + t->prd_off);
151
152
153 if (t->opts & TIMER_OPTS_ONESHOT)
154 tcr |= TCR_ENAMODE_ONESHOT << t->enamode_shift;
155 else if (t->opts & TIMER_OPTS_PERIODIC)
156 tcr |= TCR_ENAMODE_PERIODIC << t->enamode_shift;
157
158 __raw_writel(tcr, t->base + TCR);
159 }
160 return 0;
161}
162
163static inline u32 timer32_read(struct timer_s *t)
164{
165 return __raw_readl(t->base + t->tim_off);
166}
167
168static irqreturn_t timer_interrupt(int irq, void *dev_id)
169{
170 struct clock_event_device *evt = &clockevent_davinci;
171
172 evt->event_handler(evt);
173 return IRQ_HANDLED;
174}
175
176
177static irqreturn_t freerun_interrupt(int irq, void *dev_id)
178{
179 return IRQ_HANDLED;
180}
181
182static struct timer_s timers[] = {
183 [TID_CLOCKEVENT] = {
184 .name = "clockevent",
185 .opts = TIMER_OPTS_DISABLED,
186 .irqaction = {
187 .flags = IRQF_DISABLED | IRQF_TIMER,
188 .handler = timer_interrupt,
189 }
190 },
191 [TID_CLOCKSOURCE] = {
192 .name = "free-run counter",
193 .period = ~0,
194 .opts = TIMER_OPTS_PERIODIC,
195 .irqaction = {
196 .flags = IRQF_DISABLED | IRQF_TIMER,
197 .handler = freerun_interrupt,
198 }
199 },
200};
201
202static void __init timer_init(void)
203{
204 struct davinci_soc_info *soc_info = &davinci_soc_info;
205 struct davinci_timer_instance *dtip = soc_info->timer_info->timers;
206 int i;
207
208
209 for(i=0; i<2; i++) {
210 u32 tgcr;
211 void __iomem *base = dtip[i].base;
212
213
214 __raw_writel(0, base + TCR);
215
216
217 tgcr = 0;
218 __raw_writel(tgcr, base + TGCR);
219
220
221 tgcr = TGCR_TIMMODE_32BIT_UNCHAINED << TGCR_TIMMODE_SHIFT;
222 __raw_writel(tgcr, base + TGCR);
223
224
225 tgcr |= (TGCR_UNRESET << TGCR_TIM12RS_SHIFT) |
226 (TGCR_UNRESET << TGCR_TIM34RS_SHIFT);
227 __raw_writel(tgcr, base + TGCR);
228
229
230 __raw_writel(0, base + TIM12);
231 __raw_writel(0, base + TIM34);
232 }
233
234
235 for (i=0; i< ARRAY_SIZE(timers); i++) {
236 struct timer_s *t = &timers[i];
237 int timer = ID_TO_TIMER(t->id);
238 u32 irq;
239
240 t->base = dtip[timer].base;
241
242 if (IS_TIMER_BOT(t->id)) {
243 t->enamode_shift = 6;
244 t->tim_off = TIM12;
245 t->prd_off = PRD12;
246 irq = dtip[timer].bottom_irq;
247 } else {
248 t->enamode_shift = 22;
249 t->tim_off = TIM34;
250 t->prd_off = PRD34;
251 irq = dtip[timer].top_irq;
252 }
253
254
255 t->irqaction.name = t->name;
256 t->irqaction.dev_id = (void *)t;
257
258 if (t->irqaction.handler != NULL) {
259 irq = USING_COMPARE(t) ? dtip[i].cmp_irq : irq;
260 setup_irq(irq, &t->irqaction);
261 }
262
263 timer32_config(&timers[i]);
264 }
265}
266
267
268
269
270static cycle_t read_cycles(struct clocksource *cs)
271{
272 struct timer_s *t = &timers[TID_CLOCKSOURCE];
273
274 return (cycles_t)timer32_read(t);
275}
276
277static struct clocksource clocksource_davinci = {
278 .rating = 300,
279 .read = read_cycles,
280 .mask = CLOCKSOURCE_MASK(32),
281 .shift = 24,
282 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
283};
284
285
286
287
288static int davinci_set_next_event(unsigned long cycles,
289 struct clock_event_device *evt)
290{
291 struct timer_s *t = &timers[TID_CLOCKEVENT];
292
293 t->period = cycles;
294 timer32_config(t);
295 return 0;
296}
297
298static void davinci_set_mode(enum clock_event_mode mode,
299 struct clock_event_device *evt)
300{
301 struct timer_s *t = &timers[TID_CLOCKEVENT];
302
303 switch (mode) {
304 case CLOCK_EVT_MODE_PERIODIC:
305 t->period = davinci_clock_tick_rate / (HZ);
306 t->opts &= ~TIMER_OPTS_STATE_MASK;
307 t->opts |= TIMER_OPTS_PERIODIC;
308 timer32_config(t);
309 break;
310 case CLOCK_EVT_MODE_ONESHOT:
311 t->opts &= ~TIMER_OPTS_STATE_MASK;
312 t->opts |= TIMER_OPTS_ONESHOT;
313 break;
314 case CLOCK_EVT_MODE_UNUSED:
315 case CLOCK_EVT_MODE_SHUTDOWN:
316 t->opts &= ~TIMER_OPTS_STATE_MASK;
317 t->opts |= TIMER_OPTS_DISABLED;
318 break;
319 case CLOCK_EVT_MODE_RESUME:
320 break;
321 }
322}
323
324static struct clock_event_device clockevent_davinci = {
325 .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
326 .shift = 32,
327 .set_next_event = davinci_set_next_event,
328 .set_mode = davinci_set_mode,
329};
330
331
332static void __init davinci_timer_init(void)
333{
334 struct clk *timer_clk;
335 struct davinci_soc_info *soc_info = &davinci_soc_info;
336 unsigned int clockevent_id;
337 unsigned int clocksource_id;
338 static char err[] __initdata = KERN_ERR
339 "%s: can't register clocksource!\n";
340
341 clockevent_id = soc_info->timer_info->clockevent_id;
342 clocksource_id = soc_info->timer_info->clocksource_id;
343
344 timers[TID_CLOCKEVENT].id = clockevent_id;
345 timers[TID_CLOCKSOURCE].id = clocksource_id;
346
347
348
349
350
351
352 if (clockevent_id == clocksource_id) {
353 struct davinci_timer_instance *dtip =
354 soc_info->timer_info->timers;
355 int event_timer = ID_TO_TIMER(clockevent_id);
356
357
358 if (IS_TIMER_TOP(clockevent_id))
359 pr_warning("davinci_timer_init: Invalid use"
360 " of system timers. Results unpredictable.\n");
361 else if ((dtip[event_timer].cmp_off == 0)
362 || (dtip[event_timer].cmp_irq == 0))
363 pr_warning("davinci_timer_init: Invalid timer instance"
364 " setup. Results unpredictable.\n");
365 else {
366 timers[TID_CLOCKEVENT].opts |= TIMER_OPTS_USE_COMPARE;
367 clockevent_davinci.features = CLOCK_EVT_FEAT_ONESHOT;
368 }
369 }
370
371
372 timer_init();
373
374 timer_clk = clk_get(NULL, "timer0");
375 BUG_ON(IS_ERR(timer_clk));
376 clk_enable(timer_clk);
377
378 davinci_clock_tick_rate = clk_get_rate(timer_clk);
379
380
381 clocksource_davinci.name = id_to_name[clocksource_id];
382 clocksource_davinci.mult =
383 clocksource_khz2mult(davinci_clock_tick_rate/1000,
384 clocksource_davinci.shift);
385 if (clocksource_register(&clocksource_davinci))
386 printk(err, clocksource_davinci.name);
387
388
389 clockevent_davinci.name = id_to_name[timers[TID_CLOCKEVENT].id];
390 clockevent_davinci.mult = div_sc(davinci_clock_tick_rate, NSEC_PER_SEC,
391 clockevent_davinci.shift);
392 clockevent_davinci.max_delta_ns =
393 clockevent_delta2ns(0xfffffffe, &clockevent_davinci);
394 clockevent_davinci.min_delta_ns = 50000;
395
396 clockevent_davinci.cpumask = cpumask_of(0);
397 clockevents_register_device(&clockevent_davinci);
398}
399
400struct sys_timer davinci_timer = {
401 .init = davinci_timer_init,
402};
403
404
405
406void davinci_watchdog_reset(void)
407{
408 u32 tgcr, wdtcr;
409 struct platform_device *pdev = &davinci_wdt_device;
410 void __iomem *base = IO_ADDRESS(pdev->resource[0].start);
411 struct clk *wd_clk;
412
413 wd_clk = clk_get(&pdev->dev, NULL);
414 if (WARN_ON(IS_ERR(wd_clk)))
415 return;
416 clk_enable(wd_clk);
417
418
419 __raw_writel(0, base + TCR);
420
421
422 tgcr = 0;
423 __raw_writel(tgcr, base + TGCR);
424 tgcr = TGCR_TIMMODE_64BIT_WDOG << TGCR_TIMMODE_SHIFT;
425 tgcr |= (TGCR_UNRESET << TGCR_TIM12RS_SHIFT) |
426 (TGCR_UNRESET << TGCR_TIM34RS_SHIFT);
427 __raw_writel(tgcr, base + TGCR);
428
429
430 __raw_writel(0, base + TIM12);
431 __raw_writel(0, base + TIM34);
432 __raw_writel(0, base + PRD12);
433 __raw_writel(0, base + PRD34);
434
435
436 wdtcr = __raw_readl(base + WDTCR);
437 wdtcr = (WDTCR_WDKEY_SEQ0 << WDTCR_WDKEY_SHIFT) |
438 (WDTCR_WDEN_ENABLE << WDTCR_WDEN_SHIFT);
439 __raw_writel(wdtcr, base + WDTCR);
440
441
442 wdtcr = (WDTCR_WDKEY_SEQ1 << WDTCR_WDKEY_SHIFT) |
443 (WDTCR_WDEN_ENABLE << WDTCR_WDEN_SHIFT);
444 __raw_writel(wdtcr, base + WDTCR);
445
446
447
448 wdtcr = 0x00004000;
449 __raw_writel(wdtcr, base + WDTCR);
450}
451