3 * Copyright (C) 2007 Google, Inc.
4 * Copyright (c) 2009-2011, Code Aurora Forum. All rights reserved.
6 * This software is licensed under the terms of the GNU General Public
7 * License version 2, as published by the Free Software Foundation, and
8 * may be copied, distributed, and modified under those terms.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
17 #include <linux/clocksource.h>
18 #include <linux/clockchips.h>
19 #include <linux/init.h>
20 #include <linux/interrupt.h>
21 #include <linux/irq.h>
24 #include <asm/mach/time.h>
25 #include <asm/hardware/gic.h>
26 #include <asm/localtimer.h>
28 #include <mach/msm_iomap.h>
30 #include <mach/board.h>
32 #define TIMER_MATCH_VAL 0x0000
33 #define TIMER_COUNT_VAL 0x0004
34 #define TIMER_ENABLE 0x0008
35 #define TIMER_ENABLE_CLR_ON_MATCH_EN BIT(1)
36 #define TIMER_ENABLE_EN BIT(0)
37 #define TIMER_CLEAR 0x000C
38 #define DGT_CLK_CTL 0x0034
39 #define DGT_CLK_CTL_DIV_4 0x3
43 #define MSM_GLOBAL_TIMER MSM_CLOCK_GPT
45 /* TODO: Remove these ifdefs */
46 #if defined(CONFIG_ARCH_QSD8X50)
47 #define DGT_HZ (19200000 / 4) /* 19.2 MHz / 4 by default */
48 #define MSM_DGT_SHIFT (0)
49 #elif defined(CONFIG_ARCH_MSM7X30)
50 #define DGT_HZ (24576000 / 4) /* 24.576 MHz (LPXO) / 4 by default */
51 #define MSM_DGT_SHIFT (0)
52 #elif defined(CONFIG_ARCH_MSM8X60) || defined(CONFIG_ARCH_MSM8960)
53 #define DGT_HZ (27000000 / 4) /* 27 MHz (PXO) / 4 by default */
54 #define MSM_DGT_SHIFT (0)
56 #define DGT_HZ 19200000 /* 19.2 MHz or 600 KHz after shift */
57 #define MSM_DGT_SHIFT (5)
61 struct clock_event_device clockevent;
62 struct clocksource clocksource;
64 void __iomem *regbase;
67 void __iomem *global_counter;
68 void __iomem *local_counter;
70 struct clock_event_device *evt;
71 struct clock_event_device __percpu **percpu_evt;
82 static struct msm_clock msm_clocks[];
84 static struct msm_clock *clockevent_to_clock(struct clock_event_device *evt);
86 static irqreturn_t msm_timer_interrupt(int irq, void *dev_id)
88 struct clock_event_device *evt = *(struct clock_event_device **)dev_id;
89 if (evt->event_handler == NULL)
91 /* Stop the timer tick */
92 if (evt->mode == CLOCK_EVT_MODE_ONESHOT) {
93 struct msm_clock *clock = clockevent_to_clock(evt);
94 u32 ctrl = readl_relaxed(clock->regbase + TIMER_ENABLE);
95 ctrl &= ~TIMER_ENABLE_EN;
96 writel_relaxed(ctrl, clock->regbase + TIMER_ENABLE);
98 evt->event_handler(evt);
102 static cycle_t msm_read_timer_count(struct clocksource *cs)
104 struct msm_clock *clk = container_of(cs, struct msm_clock, clocksource);
107 * Shift timer count down by a constant due to unreliable lower bits
110 return readl(clk->global_counter) >> clk->shift;
113 static struct msm_clock *clockevent_to_clock(struct clock_event_device *evt)
117 for (i = 0; i < NR_TIMERS; i++)
118 if (evt == &(msm_clocks[i].clockevent))
119 return &msm_clocks[i];
120 return &msm_clocks[MSM_GLOBAL_TIMER];
122 return container_of(evt, struct msm_clock, clockevent);
126 static int msm_timer_set_next_event(unsigned long cycles,
127 struct clock_event_device *evt)
129 struct msm_clock *clock = clockevent_to_clock(evt);
130 u32 match = cycles << clock->shift;
131 u32 ctrl = readl_relaxed(clock->regbase + TIMER_ENABLE);
133 writel_relaxed(0, clock->regbase + TIMER_CLEAR);
134 writel_relaxed(match, clock->regbase + TIMER_MATCH_VAL);
135 writel_relaxed(ctrl | TIMER_ENABLE_EN, clock->regbase + TIMER_ENABLE);
139 static void msm_timer_set_mode(enum clock_event_mode mode,
140 struct clock_event_device *evt)
142 struct msm_clock *clock = clockevent_to_clock(evt);
145 ctrl = readl_relaxed(clock->regbase + TIMER_ENABLE);
146 ctrl &= ~(TIMER_ENABLE_EN | TIMER_ENABLE_CLR_ON_MATCH_EN);
149 case CLOCK_EVT_MODE_RESUME:
150 case CLOCK_EVT_MODE_PERIODIC:
152 case CLOCK_EVT_MODE_ONESHOT:
153 /* Timer is enabled in set_next_event */
155 case CLOCK_EVT_MODE_UNUSED:
156 case CLOCK_EVT_MODE_SHUTDOWN:
159 writel_relaxed(ctrl, clock->regbase + TIMER_ENABLE);
162 static struct msm_clock msm_clocks[] = {
166 .features = CLOCK_EVT_FEAT_ONESHOT,
169 .set_next_event = msm_timer_set_next_event,
170 .set_mode = msm_timer_set_mode,
172 .irq = INT_GP_TIMER_EXP,
179 .read = msm_read_timer_count,
180 .mask = CLOCKSOURCE_MASK((32 - MSM_DGT_SHIFT)),
181 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
183 .freq = DGT_HZ >> MSM_DGT_SHIFT,
184 .shift = MSM_DGT_SHIFT,
188 static void __init msm_timer_init(void)
190 struct msm_clock *clock;
191 struct clock_event_device *ce = &msm_clocks[MSM_CLOCK_GPT].clockevent;
192 struct clocksource *cs = &msm_clocks[MSM_CLOCK_DGT].clocksource;
194 int global_offset = 0;
197 if (cpu_is_msm7x01()) {
198 msm_clocks[MSM_CLOCK_GPT].regbase = MSM_CSR_BASE;
199 msm_clocks[MSM_CLOCK_DGT].regbase = MSM_CSR_BASE + 0x10;
200 } else if (cpu_is_msm7x30()) {
201 msm_clocks[MSM_CLOCK_GPT].regbase = MSM_CSR_BASE + 0x04;
202 msm_clocks[MSM_CLOCK_DGT].regbase = MSM_CSR_BASE + 0x24;
203 } else if (cpu_is_qsd8x50()) {
204 msm_clocks[MSM_CLOCK_GPT].regbase = MSM_CSR_BASE;
205 msm_clocks[MSM_CLOCK_DGT].regbase = MSM_CSR_BASE + 0x10;
206 } else if (cpu_is_msm8x60() || cpu_is_msm8960()) {
207 msm_clocks[MSM_CLOCK_GPT].regbase = MSM_TMR_BASE + 0x04;
208 msm_clocks[MSM_CLOCK_DGT].regbase = MSM_TMR_BASE + 0x24;
210 /* Use CPU0's timer as the global timer. */
211 global_offset = MSM_TMR0_BASE - MSM_TMR_BASE;
215 #ifdef CONFIG_ARCH_MSM_SCORPIONMP
216 writel(DGT_CLK_CTL_DIV_4, MSM_TMR_BASE + DGT_CLK_CTL);
219 clock = &msm_clocks[MSM_CLOCK_GPT];
220 clock->local_counter = clock->regbase + TIMER_COUNT_VAL;
222 writel_relaxed(0, clock->regbase + TIMER_ENABLE);
223 writel_relaxed(0, clock->regbase + TIMER_CLEAR);
224 writel_relaxed(~0, clock->regbase + TIMER_MATCH_VAL);
225 ce->mult = div_sc(clock->freq, NSEC_PER_SEC, ce->shift);
227 * allow at least 10 seconds to notice that the timer
231 clockevent_delta2ns(0xf0000000 >> clock->shift, ce);
232 /* 4 gets rounded down to 3 */
233 ce->min_delta_ns = clockevent_delta2ns(4, ce);
234 ce->cpumask = cpumask_of(0);
236 ce->irq = clock->irq;
237 if (cpu_is_msm8x60() || cpu_is_msm8960()) {
238 clock->percpu_evt = alloc_percpu(struct clock_event_device *);
239 if (!clock->percpu_evt) {
240 pr_err("memory allocation failed for %s\n", ce->name);
244 *__this_cpu_ptr(clock->percpu_evt) = ce;
245 res = request_percpu_irq(ce->irq, msm_timer_interrupt,
246 ce->name, clock->percpu_evt);
248 enable_percpu_irq(ce->irq, 0);
251 res = request_irq(ce->irq, msm_timer_interrupt,
252 IRQF_TIMER | IRQF_NOBALANCING |
253 IRQF_TRIGGER_RISING, ce->name, &clock->evt);
257 pr_err("request_irq failed for %s\n", ce->name);
259 clockevents_register_device(ce);
261 clock = &msm_clocks[MSM_CLOCK_DGT];
262 clock->local_counter = clock->regbase + TIMER_COUNT_VAL;
263 clock->global_counter = clock->local_counter + global_offset;
264 writel_relaxed(TIMER_ENABLE_EN, clock->regbase + TIMER_ENABLE);
265 res = clocksource_register_hz(cs, clock->freq);
267 pr_err("clocksource_register failed for %s\n", cs->name);
270 #ifdef CONFIG_LOCAL_TIMERS
271 int __cpuinit local_timer_setup(struct clock_event_device *evt)
273 static bool local_timer_inited;
274 struct msm_clock *clock = &msm_clocks[MSM_GLOBAL_TIMER];
276 /* Use existing clock_event for cpu 0 */
277 if (!smp_processor_id())
280 if (!local_timer_inited) {
281 writel(0, clock->regbase + TIMER_ENABLE);
282 writel(0, clock->regbase + TIMER_CLEAR);
283 writel(~0, clock->regbase + TIMER_MATCH_VAL);
284 local_timer_inited = true;
286 evt->irq = clock->irq;
287 evt->name = "local_timer";
288 evt->features = CLOCK_EVT_FEAT_ONESHOT;
289 evt->rating = clock->clockevent.rating;
290 evt->set_mode = msm_timer_set_mode;
291 evt->set_next_event = msm_timer_set_next_event;
292 evt->shift = clock->clockevent.shift;
293 evt->mult = div_sc(clock->freq, NSEC_PER_SEC, evt->shift);
295 clockevent_delta2ns(0xf0000000 >> clock->shift, evt);
296 evt->min_delta_ns = clockevent_delta2ns(4, evt);
298 *__this_cpu_ptr(clock->percpu_evt) = evt;
299 enable_percpu_irq(evt->irq, 0);
301 clockevents_register_device(evt);
305 void local_timer_stop(struct clock_event_device *evt)
307 evt->set_mode(CLOCK_EVT_MODE_UNUSED, evt);
308 disable_percpu_irq(evt->irq);
310 #endif /* CONFIG_LOCAL_TIMERS */
312 struct sys_timer msm_timer = {
313 .init = msm_timer_init