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authorTony Lindgren <tony@atomide.com>2011-03-29 18:54:50 -0400
committerTony Lindgren <tony@atomide.com>2011-06-27 15:14:02 -0400
commit0f622e8cae379ee17e1ffe867336b74c5b16f958 (patch)
tree9df899f87b8bca9e35a5d448ebe5d99135f94116 /arch/arm/mach-omap2/timer.c
parent0c336dc5ec492886620d4afdc252c63f32adbd0e (diff)
omap2+: Rename timer-gp.c into timer.c to combine timer init functions
We can keep everything sys_timer and gptimer.c related code in timer.c as the code will be very minimal. Later on we can also remove timer-mpu.c, as it can be called from omap4_timer_init function. This allows us to get rid of confusing existing files. We currently have timer-gp.c, timer-mpu.c, and patches have been posted to add dmtimer.c. There's no need to have these multiple files, we can put everything into timer.c. Signed-off-by: Tony Lindgren <tony@atomide.com>
Diffstat (limited to 'arch/arm/mach-omap2/timer.c')
-rw-r--r--arch/arm/mach-omap2/timer.c342
1 files changed, 342 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/timer.c b/arch/arm/mach-omap2/timer.c
new file mode 100644
index 000000000000..e9640728239b
--- /dev/null
+++ b/arch/arm/mach-omap2/timer.c
@@ -0,0 +1,342 @@
1/*
2 * linux/arch/arm/mach-omap2/timer.c
3 *
4 * OMAP2 GP timer support.
5 *
6 * Copyright (C) 2009 Nokia Corporation
7 *
8 * Update to use new clocksource/clockevent layers
9 * Author: Kevin Hilman, MontaVista Software, Inc. <source@mvista.com>
10 * Copyright (C) 2007 MontaVista Software, Inc.
11 *
12 * Original driver:
13 * Copyright (C) 2005 Nokia Corporation
14 * Author: Paul Mundt <paul.mundt@nokia.com>
15 * Juha Yrjölä <juha.yrjola@nokia.com>
16 * OMAP Dual-mode timer framework support by Timo Teras
17 *
18 * Some parts based off of TI's 24xx code:
19 *
20 * Copyright (C) 2004-2009 Texas Instruments, Inc.
21 *
22 * Roughly modelled after the OMAP1 MPU timer code.
23 * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
24 *
25 * This file is subject to the terms and conditions of the GNU General Public
26 * License. See the file "COPYING" in the main directory of this archive
27 * for more details.
28 */
29#include <linux/init.h>
30#include <linux/time.h>
31#include <linux/interrupt.h>
32#include <linux/err.h>
33#include <linux/clk.h>
34#include <linux/delay.h>
35#include <linux/irq.h>
36#include <linux/clocksource.h>
37#include <linux/clockchips.h>
38
39#include <asm/mach/time.h>
40#include <plat/dmtimer.h>
41#include <asm/localtimer.h>
42#include <asm/sched_clock.h>
43#include <plat/common.h>
44#include <plat/omap_hwmod.h>
45
46/* Parent clocks, eventually these will come from the clock framework */
47
48#define OMAP2_MPU_SOURCE "sys_ck"
49#define OMAP3_MPU_SOURCE OMAP2_MPU_SOURCE
50#define OMAP4_MPU_SOURCE "sys_clkin_ck"
51#define OMAP2_32K_SOURCE "func_32k_ck"
52#define OMAP3_32K_SOURCE "omap_32k_fck"
53#define OMAP4_32K_SOURCE "sys_32k_ck"
54
55#ifdef CONFIG_OMAP_32K_TIMER
56#define OMAP2_CLKEV_SOURCE OMAP2_32K_SOURCE
57#define OMAP3_CLKEV_SOURCE OMAP3_32K_SOURCE
58#define OMAP4_CLKEV_SOURCE OMAP4_32K_SOURCE
59#define OMAP3_SECURE_TIMER 12
60#else
61#define OMAP2_CLKEV_SOURCE OMAP2_MPU_SOURCE
62#define OMAP3_CLKEV_SOURCE OMAP3_MPU_SOURCE
63#define OMAP4_CLKEV_SOURCE OMAP4_MPU_SOURCE
64#define OMAP3_SECURE_TIMER 1
65#endif
66
67/* MAX_GPTIMER_ID: number of GPTIMERs on the chip */
68#define MAX_GPTIMER_ID 12
69
70u32 sys_timer_reserved;
71
72/* Clockevent code */
73
74static struct omap_dm_timer clkev;
75static struct clock_event_device clockevent_gpt;
76
77static irqreturn_t omap2_gp_timer_interrupt(int irq, void *dev_id)
78{
79 struct clock_event_device *evt = &clockevent_gpt;
80
81 __omap_dm_timer_write_status(clkev.io_base, OMAP_TIMER_INT_OVERFLOW);
82
83 evt->event_handler(evt);
84 return IRQ_HANDLED;
85}
86
87static struct irqaction omap2_gp_timer_irq = {
88 .name = "gp timer",
89 .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
90 .handler = omap2_gp_timer_interrupt,
91};
92
93static int omap2_gp_timer_set_next_event(unsigned long cycles,
94 struct clock_event_device *evt)
95{
96 __omap_dm_timer_load_start(clkev.io_base, OMAP_TIMER_CTRL_ST,
97 0xffffffff - cycles, 1);
98
99 return 0;
100}
101
102static void omap2_gp_timer_set_mode(enum clock_event_mode mode,
103 struct clock_event_device *evt)
104{
105 u32 period;
106
107 __omap_dm_timer_stop(clkev.io_base, 1, clkev.rate);
108
109 switch (mode) {
110 case CLOCK_EVT_MODE_PERIODIC:
111 period = clkev.rate / HZ;
112 period -= 1;
113 /* Looks like we need to first set the load value separately */
114 __omap_dm_timer_write(clkev.io_base, OMAP_TIMER_LOAD_REG,
115 0xffffffff - period, 1);
116 __omap_dm_timer_load_start(clkev.io_base,
117 OMAP_TIMER_CTRL_AR | OMAP_TIMER_CTRL_ST,
118 0xffffffff - period, 1);
119 break;
120 case CLOCK_EVT_MODE_ONESHOT:
121 break;
122 case CLOCK_EVT_MODE_UNUSED:
123 case CLOCK_EVT_MODE_SHUTDOWN:
124 case CLOCK_EVT_MODE_RESUME:
125 break;
126 }
127}
128
129static struct clock_event_device clockevent_gpt = {
130 .name = "gp timer",
131 .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
132 .shift = 32,
133 .set_next_event = omap2_gp_timer_set_next_event,
134 .set_mode = omap2_gp_timer_set_mode,
135};
136
137static int __init omap_dm_timer_init_one(struct omap_dm_timer *timer,
138 int gptimer_id,
139 const char *fck_source)
140{
141 char name[10]; /* 10 = sizeof("gptXX_Xck0") */
142 struct omap_hwmod *oh;
143 size_t size;
144 int res = 0;
145
146 sprintf(name, "timer%d", gptimer_id);
147 omap_hwmod_setup_one(name);
148 oh = omap_hwmod_lookup(name);
149 if (!oh)
150 return -ENODEV;
151
152 timer->irq = oh->mpu_irqs[0].irq;
153 timer->phys_base = oh->slaves[0]->addr->pa_start;
154 size = oh->slaves[0]->addr->pa_end - timer->phys_base;
155
156 /* Static mapping, never released */
157 timer->io_base = ioremap(timer->phys_base, size);
158 if (!timer->io_base)
159 return -ENXIO;
160
161 /* After the dmtimer is using hwmod these clocks won't be needed */
162 sprintf(name, "gpt%d_fck", gptimer_id);
163 timer->fclk = clk_get(NULL, name);
164 if (IS_ERR(timer->fclk))
165 return -ENODEV;
166
167 sprintf(name, "gpt%d_ick", gptimer_id);
168 timer->iclk = clk_get(NULL, name);
169 if (IS_ERR(timer->iclk)) {
170 clk_put(timer->fclk);
171 return -ENODEV;
172 }
173
174 omap_hwmod_enable(oh);
175
176 sys_timer_reserved |= (1 << (gptimer_id - 1));
177
178 if (gptimer_id != 12) {
179 struct clk *src;
180
181 src = clk_get(NULL, fck_source);
182 if (IS_ERR(src)) {
183 res = -EINVAL;
184 } else {
185 res = __omap_dm_timer_set_source(timer->fclk, src);
186 if (IS_ERR_VALUE(res))
187 pr_warning("%s: timer%i cannot set source\n",
188 __func__, gptimer_id);
189 clk_put(src);
190 }
191 }
192 __omap_dm_timer_reset(timer->io_base, 1, 1);
193 timer->posted = 1;
194
195 timer->rate = clk_get_rate(timer->fclk);
196
197 timer->reserved = 1;
198
199 return res;
200}
201
202static void __init omap2_gp_clockevent_init(int gptimer_id,
203 const char *fck_source)
204{
205 int res;
206
207 res = omap_dm_timer_init_one(&clkev, gptimer_id, fck_source);
208 BUG_ON(res);
209
210 omap2_gp_timer_irq.dev_id = (void *)&clkev;
211 setup_irq(clkev.irq, &omap2_gp_timer_irq);
212
213 __omap_dm_timer_int_enable(clkev.io_base, OMAP_TIMER_INT_OVERFLOW);
214
215 clockevent_gpt.mult = div_sc(clkev.rate, NSEC_PER_SEC,
216 clockevent_gpt.shift);
217 clockevent_gpt.max_delta_ns =
218 clockevent_delta2ns(0xffffffff, &clockevent_gpt);
219 clockevent_gpt.min_delta_ns =
220 clockevent_delta2ns(3, &clockevent_gpt);
221 /* Timer internal resynch latency. */
222
223 clockevent_gpt.cpumask = cpumask_of(0);
224 clockevents_register_device(&clockevent_gpt);
225
226 pr_info("OMAP clockevent source: GPTIMER%d at %lu Hz\n",
227 gptimer_id, clkev.rate);
228}
229
230/* Clocksource code */
231
232#ifdef CONFIG_OMAP_32K_TIMER
233/*
234 * When 32k-timer is enabled, don't use GPTimer for clocksource
235 * instead, just leave default clocksource which uses the 32k
236 * sync counter. See clocksource setup in plat-omap/counter_32k.c
237 */
238
239static void __init omap2_gp_clocksource_init(int unused, const char *dummy)
240{
241 omap_init_clocksource_32k();
242}
243
244#else
245
246static struct omap_dm_timer clksrc;
247
248/*
249 * clocksource
250 */
251static DEFINE_CLOCK_DATA(cd);
252static cycle_t clocksource_read_cycles(struct clocksource *cs)
253{
254 return (cycle_t)__omap_dm_timer_read_counter(clksrc.io_base, 1);
255}
256
257static struct clocksource clocksource_gpt = {
258 .name = "gp timer",
259 .rating = 300,
260 .read = clocksource_read_cycles,
261 .mask = CLOCKSOURCE_MASK(32),
262 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
263};
264
265static void notrace dmtimer_update_sched_clock(void)
266{
267 u32 cyc;
268
269 cyc = __omap_dm_timer_read_counter(clksrc.io_base, 1);
270
271 update_sched_clock(&cd, cyc, (u32)~0);
272}
273
274unsigned long long notrace sched_clock(void)
275{
276 u32 cyc = 0;
277
278 if (clksrc.reserved)
279 cyc = __omap_dm_timer_read_counter(clksrc.io_base, 1);
280
281 return cyc_to_sched_clock(&cd, cyc, (u32)~0);
282}
283
284/* Setup free-running counter for clocksource */
285static void __init omap2_gp_clocksource_init(int gptimer_id,
286 const char *fck_source)
287{
288 int res;
289
290 res = omap_dm_timer_init_one(&clksrc, gptimer_id, fck_source);
291 BUG_ON(res);
292
293 pr_info("OMAP clocksource: GPTIMER%d at %lu Hz\n",
294 gptimer_id, clksrc.rate);
295
296 __omap_dm_timer_load_start(clksrc.io_base, OMAP_TIMER_CTRL_ST, 0, 1);
297 init_sched_clock(&cd, dmtimer_update_sched_clock, 32, clksrc.rate);
298
299 if (clocksource_register_hz(&clocksource_gpt, clksrc.rate))
300 pr_err("Could not register clocksource %s\n",
301 clocksource_gpt.name);
302}
303#endif
304
305#define OMAP_SYS_TIMER_INIT(name, clkev_nr, clkev_src, \
306 clksrc_nr, clksrc_src) \
307static void __init omap##name##_timer_init(void) \
308{ \
309 omap2_gp_clockevent_init((clkev_nr), clkev_src); \
310 omap2_gp_clocksource_init((clksrc_nr), clksrc_src); \
311}
312
313#define OMAP_SYS_TIMER(name) \
314struct sys_timer omap##name##_timer = { \
315 .init = omap##name##_timer_init, \
316};
317
318#ifdef CONFIG_ARCH_OMAP2
319OMAP_SYS_TIMER_INIT(2, 1, OMAP2_CLKEV_SOURCE, 2, OMAP2_MPU_SOURCE)
320OMAP_SYS_TIMER(2)
321#endif
322
323#ifdef CONFIG_ARCH_OMAP3
324OMAP_SYS_TIMER_INIT(3, 1, OMAP3_CLKEV_SOURCE, 2, OMAP3_MPU_SOURCE)
325OMAP_SYS_TIMER(3)
326OMAP_SYS_TIMER_INIT(3_secure, OMAP3_SECURE_TIMER, OMAP3_CLKEV_SOURCE,
327 2, OMAP3_MPU_SOURCE)
328OMAP_SYS_TIMER(3_secure)
329#endif
330
331#ifdef CONFIG_ARCH_OMAP4
332static void __init omap4_timer_init(void)
333{
334#ifdef CONFIG_LOCAL_TIMERS
335 twd_base = ioremap(OMAP44XX_LOCAL_TWD_BASE, SZ_256);
336 BUG_ON(!twd_base);
337#endif
338 omap2_gp_clockevent_init(1, OMAP4_CLKEV_SOURCE);
339 omap2_gp_clocksource_init(2, OMAP4_MPU_SOURCE);
340}
341OMAP_SYS_TIMER(4)
342#endif