]>
Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
3b59b6be | 2 | * linux/arch/arm/mach-omap1/time.c |
1da177e4 LT |
3 | * |
4 | * OMAP Timers | |
5 | * | |
6 | * Copyright (C) 2004 Nokia Corporation | |
b3402cf5 | 7 | * Partial timer rewrite and additional dynamic tick timer support by |
1da177e4 LT |
8 | * Tony Lindgen <tony@atomide.com> and |
9 | * Tuukka Tikkanen <tuukka.tikkanen@elektrobit.com> | |
10 | * | |
11 | * MPU timer code based on the older MPU timer code for OMAP | |
12 | * Copyright (C) 2000 RidgeRun, Inc. | |
13 | * Author: Greg Lonnon <glonnon@ridgerun.com> | |
14 | * | |
15 | * This program is free software; you can redistribute it and/or modify it | |
16 | * under the terms of the GNU General Public License as published by the | |
17 | * Free Software Foundation; either version 2 of the License, or (at your | |
18 | * option) any later version. | |
19 | * | |
20 | * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED | |
21 | * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF | |
22 | * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN | |
23 | * NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, | |
24 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT | |
25 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF | |
26 | * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON | |
27 | * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | |
28 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF | |
29 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
30 | * | |
31 | * You should have received a copy of the GNU General Public License along | |
32 | * with this program; if not, write to the Free Software Foundation, Inc., | |
33 | * 675 Mass Ave, Cambridge, MA 02139, USA. | |
34 | */ | |
35 | ||
1da177e4 LT |
36 | #include <linux/kernel.h> |
37 | #include <linux/init.h> | |
38 | #include <linux/delay.h> | |
39 | #include <linux/interrupt.h> | |
40 | #include <linux/sched.h> | |
41 | #include <linux/spinlock.h> | |
075192ae KH |
42 | #include <linux/clk.h> |
43 | #include <linux/err.h> | |
44 | #include <linux/clocksource.h> | |
45 | #include <linux/clockchips.h> | |
fced80c7 | 46 | #include <linux/io.h> |
1da177e4 LT |
47 | |
48 | #include <asm/system.h> | |
a09e64fb | 49 | #include <mach/hardware.h> |
1da177e4 LT |
50 | #include <asm/leds.h> |
51 | #include <asm/irq.h> | |
52 | #include <asm/mach/irq.h> | |
53 | #include <asm/mach/time.h> | |
54 | ||
1da177e4 | 55 | |
1da177e4 LT |
56 | #define OMAP_MPU_TIMER_BASE OMAP_MPU_TIMER1_BASE |
57 | #define OMAP_MPU_TIMER_OFFSET 0x100 | |
58 | ||
1da177e4 LT |
59 | typedef struct { |
60 | u32 cntl; /* CNTL_TIMER, R/W */ | |
61 | u32 load_tim; /* LOAD_TIM, W */ | |
62 | u32 read_tim; /* READ_TIM, R */ | |
63 | } omap_mpu_timer_regs_t; | |
64 | ||
65 | #define omap_mpu_timer_base(n) \ | |
66 | ((volatile omap_mpu_timer_regs_t*)IO_ADDRESS(OMAP_MPU_TIMER_BASE + \ | |
67 | (n)*OMAP_MPU_TIMER_OFFSET)) | |
68 | ||
69 | static inline unsigned long omap_mpu_timer_read(int nr) | |
70 | { | |
71 | volatile omap_mpu_timer_regs_t* timer = omap_mpu_timer_base(nr); | |
72 | return timer->read_tim; | |
73 | } | |
74 | ||
075192ae | 75 | static inline void omap_mpu_set_autoreset(int nr) |
1da177e4 LT |
76 | { |
77 | volatile omap_mpu_timer_regs_t* timer = omap_mpu_timer_base(nr); | |
78 | ||
075192ae | 79 | timer->cntl = timer->cntl | MPU_TIMER_AR; |
1da177e4 LT |
80 | } |
81 | ||
075192ae | 82 | static inline void omap_mpu_remove_autoreset(int nr) |
1da177e4 | 83 | { |
075192ae | 84 | volatile omap_mpu_timer_regs_t* timer = omap_mpu_timer_base(nr); |
1da177e4 | 85 | |
075192ae | 86 | timer->cntl = timer->cntl & ~MPU_TIMER_AR; |
1da177e4 LT |
87 | } |
88 | ||
075192ae KH |
89 | static inline void omap_mpu_timer_start(int nr, unsigned long load_val, |
90 | int autoreset) | |
91 | { | |
92 | volatile omap_mpu_timer_regs_t* timer = omap_mpu_timer_base(nr); | |
93 | unsigned int timerflags = (MPU_TIMER_CLOCK_ENABLE | MPU_TIMER_ST); | |
94 | ||
95 | if (autoreset) timerflags |= MPU_TIMER_AR; | |
96 | ||
97 | timer->cntl = MPU_TIMER_CLOCK_ENABLE; | |
98 | udelay(1); | |
99 | timer->load_tim = load_val; | |
100 | udelay(1); | |
101 | timer->cntl = timerflags; | |
102 | } | |
1da177e4 | 103 | |
06cad098 KH |
104 | static inline void omap_mpu_timer_stop(int nr) |
105 | { | |
106 | volatile omap_mpu_timer_regs_t* timer = omap_mpu_timer_base(nr); | |
107 | ||
108 | timer->cntl &= ~MPU_TIMER_ST; | |
109 | } | |
110 | ||
1da177e4 | 111 | /* |
075192ae KH |
112 | * --------------------------------------------------------------------------- |
113 | * MPU timer 1 ... count down to zero, interrupt, reload | |
114 | * --------------------------------------------------------------------------- | |
1da177e4 | 115 | */ |
075192ae | 116 | static int omap_mpu_set_next_event(unsigned long cycles, |
06cad098 | 117 | struct clock_event_device *evt) |
1da177e4 | 118 | { |
075192ae KH |
119 | omap_mpu_timer_start(0, cycles, 0); |
120 | return 0; | |
121 | } | |
1da177e4 | 122 | |
075192ae KH |
123 | static void omap_mpu_set_mode(enum clock_event_mode mode, |
124 | struct clock_event_device *evt) | |
125 | { | |
126 | switch (mode) { | |
127 | case CLOCK_EVT_MODE_PERIODIC: | |
128 | omap_mpu_set_autoreset(0); | |
129 | break; | |
130 | case CLOCK_EVT_MODE_ONESHOT: | |
06cad098 | 131 | omap_mpu_timer_stop(0); |
075192ae KH |
132 | omap_mpu_remove_autoreset(0); |
133 | break; | |
134 | case CLOCK_EVT_MODE_UNUSED: | |
135 | case CLOCK_EVT_MODE_SHUTDOWN: | |
18de5bc4 | 136 | case CLOCK_EVT_MODE_RESUME: |
075192ae KH |
137 | break; |
138 | } | |
1da177e4 LT |
139 | } |
140 | ||
075192ae KH |
141 | static struct clock_event_device clockevent_mpu_timer1 = { |
142 | .name = "mpu_timer1", | |
c6b349ed | 143 | .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, |
075192ae KH |
144 | .shift = 32, |
145 | .set_next_event = omap_mpu_set_next_event, | |
146 | .set_mode = omap_mpu_set_mode, | |
147 | }; | |
148 | ||
149 | static irqreturn_t omap_mpu_timer1_interrupt(int irq, void *dev_id) | |
1da177e4 | 150 | { |
075192ae | 151 | struct clock_event_device *evt = &clockevent_mpu_timer1; |
1da177e4 | 152 | |
075192ae | 153 | evt->event_handler(evt); |
1da177e4 LT |
154 | |
155 | return IRQ_HANDLED; | |
156 | } | |
157 | ||
075192ae KH |
158 | static struct irqaction omap_mpu_timer1_irq = { |
159 | .name = "mpu_timer1", | |
b30fabad | 160 | .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL, |
075192ae | 161 | .handler = omap_mpu_timer1_interrupt, |
1da177e4 LT |
162 | }; |
163 | ||
075192ae KH |
164 | static __init void omap_init_mpu_timer(unsigned long rate) |
165 | { | |
075192ae KH |
166 | setup_irq(INT_TIMER1, &omap_mpu_timer1_irq); |
167 | omap_mpu_timer_start(0, (rate / HZ) - 1, 1); | |
168 | ||
169 | clockevent_mpu_timer1.mult = div_sc(rate, NSEC_PER_SEC, | |
170 | clockevent_mpu_timer1.shift); | |
171 | clockevent_mpu_timer1.max_delta_ns = | |
172 | clockevent_delta2ns(-1, &clockevent_mpu_timer1); | |
173 | clockevent_mpu_timer1.min_delta_ns = | |
174 | clockevent_delta2ns(1, &clockevent_mpu_timer1); | |
175 | ||
320ab2b0 | 176 | clockevent_mpu_timer1.cpumask = cpumask_of(0); |
075192ae KH |
177 | clockevents_register_device(&clockevent_mpu_timer1); |
178 | } | |
179 | ||
180 | ||
181 | /* | |
182 | * --------------------------------------------------------------------------- | |
183 | * MPU timer 2 ... free running 32-bit clock source and scheduler clock | |
184 | * --------------------------------------------------------------------------- | |
185 | */ | |
186 | ||
187 | static unsigned long omap_mpu_timer2_overflows; | |
188 | ||
189 | static irqreturn_t omap_mpu_timer2_interrupt(int irq, void *dev_id) | |
1da177e4 | 190 | { |
075192ae | 191 | omap_mpu_timer2_overflows++; |
1da177e4 LT |
192 | return IRQ_HANDLED; |
193 | } | |
194 | ||
075192ae KH |
195 | static struct irqaction omap_mpu_timer2_irq = { |
196 | .name = "mpu_timer2", | |
52e405ea | 197 | .flags = IRQF_DISABLED, |
075192ae | 198 | .handler = omap_mpu_timer2_interrupt, |
1da177e4 LT |
199 | }; |
200 | ||
075192ae | 201 | static cycle_t mpu_read(void) |
1da177e4 | 202 | { |
075192ae KH |
203 | return ~omap_mpu_timer_read(1); |
204 | } | |
205 | ||
206 | static struct clocksource clocksource_mpu = { | |
207 | .name = "mpu_timer2", | |
208 | .rating = 300, | |
209 | .read = mpu_read, | |
210 | .mask = CLOCKSOURCE_MASK(32), | |
211 | .shift = 24, | |
212 | .flags = CLOCK_SOURCE_IS_CONTINUOUS, | |
213 | }; | |
214 | ||
215 | static void __init omap_init_clocksource(unsigned long rate) | |
216 | { | |
217 | static char err[] __initdata = KERN_ERR | |
218 | "%s: can't register clocksource!\n"; | |
219 | ||
220 | clocksource_mpu.mult | |
221 | = clocksource_khz2mult(rate/1000, clocksource_mpu.shift); | |
222 | ||
223 | setup_irq(INT_TIMER2, &omap_mpu_timer2_irq); | |
224 | omap_mpu_timer_start(1, ~0, 1); | |
225 | ||
226 | if (clocksource_register(&clocksource_mpu)) | |
227 | printk(err, clocksource_mpu.name); | |
1da177e4 LT |
228 | } |
229 | ||
1da177e4 LT |
230 | /* |
231 | * --------------------------------------------------------------------------- | |
232 | * Timer initialization | |
233 | * --------------------------------------------------------------------------- | |
234 | */ | |
3b59b6be | 235 | static void __init omap_timer_init(void) |
1da177e4 | 236 | { |
075192ae KH |
237 | struct clk *ck_ref = clk_get(NULL, "ck_ref"); |
238 | unsigned long rate; | |
239 | ||
240 | BUG_ON(IS_ERR(ck_ref)); | |
241 | ||
242 | rate = clk_get_rate(ck_ref); | |
243 | clk_put(ck_ref); | |
244 | ||
245 | /* PTV = 0 */ | |
246 | rate /= 2; | |
247 | ||
248 | omap_init_mpu_timer(rate); | |
249 | omap_init_clocksource(rate); | |
1da177e4 LT |
250 | } |
251 | ||
252 | struct sys_timer omap_timer = { | |
253 | .init = omap_timer_init, | |
1da177e4 | 254 | }; |