2 * linux/arch/arm/mach-omap2/timer.c
4 * OMAP2 GP timer support.
6 * Copyright (C) 2009 Nokia Corporation
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.
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
18 * Some parts based off of TI's 24xx code:
20 * Copyright (C) 2004-2009 Texas Instruments, Inc.
22 * Roughly modelled after the OMAP1 MPU timer code.
23 * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
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
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 #include <linux/slab.h>
40 #include <asm/mach/time.h>
41 #include <plat/dmtimer.h>
42 #include <asm/localtimer.h>
43 #include <asm/sched_clock.h>
44 #include <plat/common.h>
45 #include <plat/omap_hwmod.h>
46 #include <plat/omap_device.h>
47 #include <plat/omap-pm.h>
49 #include "powerdomain.h"
51 /* Parent clocks, eventually these will come from the clock framework */
53 #define OMAP2_MPU_SOURCE "sys_ck"
54 #define OMAP3_MPU_SOURCE OMAP2_MPU_SOURCE
55 #define OMAP4_MPU_SOURCE "sys_clkin_ck"
56 #define OMAP2_32K_SOURCE "func_32k_ck"
57 #define OMAP3_32K_SOURCE "omap_32k_fck"
58 #define OMAP4_32K_SOURCE "sys_32k_ck"
60 #ifdef CONFIG_OMAP_32K_TIMER
61 #define OMAP2_CLKEV_SOURCE OMAP2_32K_SOURCE
62 #define OMAP3_CLKEV_SOURCE OMAP3_32K_SOURCE
63 #define OMAP4_CLKEV_SOURCE OMAP4_32K_SOURCE
64 #define OMAP3_SECURE_TIMER 12
66 #define OMAP2_CLKEV_SOURCE OMAP2_MPU_SOURCE
67 #define OMAP3_CLKEV_SOURCE OMAP3_MPU_SOURCE
68 #define OMAP4_CLKEV_SOURCE OMAP4_MPU_SOURCE
69 #define OMAP3_SECURE_TIMER 1
72 /* MAX_GPTIMER_ID: number of GPTIMERs on the chip */
73 #define MAX_GPTIMER_ID 12
75 static u32 sys_timer_reserved;
79 static struct omap_dm_timer clkev;
80 static struct clock_event_device clockevent_gpt;
82 static irqreturn_t omap2_gp_timer_interrupt(int irq, void *dev_id)
84 struct clock_event_device *evt = &clockevent_gpt;
86 __omap_dm_timer_write_status(&clkev, OMAP_TIMER_INT_OVERFLOW);
88 evt->event_handler(evt);
92 static struct irqaction omap2_gp_timer_irq = {
94 .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
95 .handler = omap2_gp_timer_interrupt,
98 static int omap2_gp_timer_set_next_event(unsigned long cycles,
99 struct clock_event_device *evt)
101 __omap_dm_timer_load_start(&clkev, OMAP_TIMER_CTRL_ST,
102 0xffffffff - cycles, OMAP_TIMER_POSTED);
107 static void omap2_gp_timer_set_mode(enum clock_event_mode mode,
108 struct clock_event_device *evt)
112 __omap_dm_timer_stop(&clkev, OMAP_TIMER_POSTED, clkev.rate);
115 case CLOCK_EVT_MODE_PERIODIC:
116 period = clkev.rate / HZ;
118 /* Looks like we need to first set the load value separately */
119 __omap_dm_timer_write(&clkev, OMAP_TIMER_LOAD_REG,
120 0xffffffff - period, OMAP_TIMER_POSTED);
121 __omap_dm_timer_load_start(&clkev,
122 OMAP_TIMER_CTRL_AR | OMAP_TIMER_CTRL_ST,
123 0xffffffff - period, OMAP_TIMER_POSTED);
125 case CLOCK_EVT_MODE_ONESHOT:
127 case CLOCK_EVT_MODE_UNUSED:
128 case CLOCK_EVT_MODE_SHUTDOWN:
129 case CLOCK_EVT_MODE_RESUME:
134 static struct clock_event_device clockevent_gpt = {
136 .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
138 .set_next_event = omap2_gp_timer_set_next_event,
139 .set_mode = omap2_gp_timer_set_mode,
143 * omap_dm_timer_get_errata - get errata flags for a timer
145 * Get the timer errata flags that are specific to the OMAP device being used.
147 u32 __init omap_dm_timer_get_errata(void)
149 if (cpu_is_omap24xx())
152 return OMAP_TIMER_ERRATA_I103_I767;
155 static int __init omap_dm_timer_init_one(struct omap_dm_timer *timer,
157 const char *fck_source,
160 char name[10]; /* 10 = sizeof("gptXX_Xck0") */
161 struct omap_hwmod *oh;
165 sprintf(name, "timer%d", gptimer_id);
166 omap_hwmod_setup_one(name);
167 oh = omap_hwmod_lookup(name);
171 timer->irq = oh->mpu_irqs[0].irq;
172 timer->phys_base = oh->slaves[0]->addr->pa_start;
173 size = oh->slaves[0]->addr->pa_end - timer->phys_base;
175 /* Static mapping, never released */
176 timer->io_base = ioremap(timer->phys_base, size);
180 /* After the dmtimer is using hwmod these clocks won't be needed */
181 sprintf(name, "gpt%d_fck", gptimer_id);
182 timer->fclk = clk_get(NULL, name);
183 if (IS_ERR(timer->fclk))
186 omap_hwmod_enable(oh);
188 sys_timer_reserved |= (1 << (gptimer_id - 1));
190 if (gptimer_id != 12) {
193 src = clk_get(NULL, fck_source);
197 res = __omap_dm_timer_set_source(timer->fclk, src);
198 if (IS_ERR_VALUE(res))
199 pr_warning("%s: timer%i cannot set source\n",
200 __func__, gptimer_id);
204 __omap_dm_timer_init_regs(timer);
205 __omap_dm_timer_reset(timer, 1, 1);
208 __omap_dm_timer_enable_posted(timer);
210 /* Check that the intended posted configuration matches the actual */
211 if (posted != timer->posted)
214 timer->rate = clk_get_rate(timer->fclk);
220 static void __init omap2_gp_clockevent_init(int gptimer_id,
221 const char *fck_source)
225 clkev.errata = omap_dm_timer_get_errata();
228 * For clock-event timers we never read the timer counter and
229 * so we are not impacted by errata i103 and i767. Therefore,
230 * we can safely ignore this errata for clock-event timers.
232 __omap_dm_timer_override_errata(&clkev, OMAP_TIMER_ERRATA_I103_I767);
234 res = omap_dm_timer_init_one(&clkev, gptimer_id, fck_source,
238 omap2_gp_timer_irq.dev_id = (void *)&clkev;
239 setup_irq(clkev.irq, &omap2_gp_timer_irq);
241 __omap_dm_timer_int_enable(&clkev, OMAP_TIMER_INT_OVERFLOW);
243 clockevent_gpt.mult = div_sc(clkev.rate, NSEC_PER_SEC,
244 clockevent_gpt.shift);
245 clockevent_gpt.max_delta_ns =
246 clockevent_delta2ns(0xffffffff, &clockevent_gpt);
247 clockevent_gpt.min_delta_ns =
248 clockevent_delta2ns(3, &clockevent_gpt);
249 /* Timer internal resynch latency. */
251 clockevent_gpt.cpumask = cpumask_of(0);
252 clockevents_register_device(&clockevent_gpt);
254 pr_info("OMAP clockevent source: GPTIMER%d at %lu Hz\n",
255 gptimer_id, clkev.rate);
258 /* Clocksource code */
260 #ifdef CONFIG_OMAP_32K_TIMER
262 * When 32k-timer is enabled, don't use GPTimer for clocksource
263 * instead, just leave default clocksource which uses the 32k
264 * sync counter. See clocksource setup in plat-omap/counter_32k.c
267 static void __init omap2_gp_clocksource_init(int unused, const char *dummy)
269 omap_init_clocksource_32k();
274 static struct omap_dm_timer clksrc;
279 static cycle_t clocksource_read_cycles(struct clocksource *cs)
281 return (cycle_t)__omap_dm_timer_read_counter(&clksrc,
282 OMAP_TIMER_NONPOSTED);
285 static struct clocksource clocksource_gpt = {
288 .read = clocksource_read_cycles,
289 .mask = CLOCKSOURCE_MASK(32),
290 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
293 static u32 notrace dmtimer_read_sched_clock(void)
296 return __omap_dm_timer_read_counter(&clksrc,
297 OMAP_TIMER_NONPOSTED);
302 /* Setup free-running counter for clocksource */
303 static void __init omap2_gp_clocksource_init(int gptimer_id,
304 const char *fck_source)
308 clksrc.errata = omap_dm_timer_get_errata();
310 res = omap_dm_timer_init_one(&clksrc, gptimer_id, fck_source,
311 OMAP_TIMER_NONPOSTED);
314 pr_info("OMAP clocksource: GPTIMER%d at %lu Hz\n",
315 gptimer_id, clksrc.rate);
317 __omap_dm_timer_load_start(&clksrc,
318 OMAP_TIMER_CTRL_ST | OMAP_TIMER_CTRL_AR, 0,
319 OMAP_TIMER_NONPOSTED);
320 setup_sched_clock(dmtimer_read_sched_clock, 32, clksrc.rate);
322 if (clocksource_register_hz(&clocksource_gpt, clksrc.rate))
323 pr_err("Could not register clocksource %s\n",
324 clocksource_gpt.name);
328 #define OMAP_SYS_TIMER_INIT(name, clkev_nr, clkev_src, \
329 clksrc_nr, clksrc_src) \
330 static void __init omap##name##_timer_init(void) \
332 omap2_gp_clockevent_init((clkev_nr), clkev_src); \
333 omap2_gp_clocksource_init((clksrc_nr), clksrc_src); \
336 #define OMAP_SYS_TIMER(name) \
337 struct sys_timer omap##name##_timer = { \
338 .init = omap##name##_timer_init, \
341 #ifdef CONFIG_ARCH_OMAP2
342 OMAP_SYS_TIMER_INIT(2, 1, OMAP2_CLKEV_SOURCE, 2, OMAP2_MPU_SOURCE)
346 #ifdef CONFIG_ARCH_OMAP3
347 OMAP_SYS_TIMER_INIT(3, 1, OMAP3_CLKEV_SOURCE, 2, OMAP3_MPU_SOURCE)
349 OMAP_SYS_TIMER_INIT(3_secure, OMAP3_SECURE_TIMER, OMAP3_CLKEV_SOURCE,
351 OMAP_SYS_TIMER(3_secure)
354 #ifdef CONFIG_ARCH_OMAP4
355 static void __init omap4_timer_init(void)
357 #ifdef CONFIG_LOCAL_TIMERS
358 twd_base = ioremap(OMAP44XX_LOCAL_TWD_BASE, SZ_256);
361 omap2_gp_clockevent_init(1, OMAP4_CLKEV_SOURCE);
362 omap2_gp_clocksource_init(2, OMAP4_MPU_SOURCE);
368 * omap2_dm_timer_set_src - change the timer input clock source
369 * @pdev: timer platform device pointer
370 * @source: array index of parent clock source
372 static int omap2_dm_timer_set_src(struct platform_device *pdev, int source)
375 struct dmtimer_platform_data *pdata = pdev->dev.platform_data;
376 struct clk *fclk, *parent;
377 char *parent_name = NULL;
379 fclk = clk_get(&pdev->dev, "fck");
380 if (IS_ERR_OR_NULL(fclk)) {
381 dev_err(&pdev->dev, "%s: %d: clk_get() FAILED\n",
387 case OMAP_TIMER_SRC_SYS_CLK:
388 parent_name = "sys_ck";
391 case OMAP_TIMER_SRC_32_KHZ:
392 parent_name = "32k_ck";
395 case OMAP_TIMER_SRC_EXT_CLK:
396 if (pdata->timer_ip_version == OMAP_TIMER_IP_VERSION_1) {
397 parent_name = "alt_ck";
400 dev_err(&pdev->dev, "%s: %d: invalid clk src.\n",
406 parent = clk_get(&pdev->dev, parent_name);
407 if (IS_ERR_OR_NULL(parent)) {
408 dev_err(&pdev->dev, "%s: %d: clk_get() %s FAILED\n",
409 __func__, __LINE__, parent_name);
414 ret = clk_set_parent(fclk, parent);
415 if (IS_ERR_VALUE(ret)) {
416 dev_err(&pdev->dev, "%s: clk_set_parent() to %s FAILED\n",
417 __func__, parent_name);
428 * omap_timer_init - build and register timer device with an
429 * associated timer hwmod
430 * @oh: timer hwmod pointer to be used to build timer device
431 * @user: parameter that can be passed from calling hwmod API
433 * Called by omap_hwmod_for_each_by_class to register each of the timer
434 * devices present in the system. The number of timer devices is known
435 * by parsing through the hwmod database for a given class name. At the
436 * end of function call memory is allocated for timer device and it is
437 * registered to the framework ready to be proved by the driver.
439 static int __init omap_timer_init(struct omap_hwmod *oh, void *unused)
443 char *name = "omap_timer";
444 struct dmtimer_platform_data *pdata;
445 struct platform_device *pdev;
446 struct omap_timer_capability_dev_attr *timer_dev_attr;
447 struct powerdomain *pwrdm;
449 pr_debug("%s: %s\n", __func__, oh->name);
451 /* on secure device, do not register secure timer */
452 timer_dev_attr = oh->dev_attr;
453 if (omap_type() != OMAP2_DEVICE_TYPE_GP && timer_dev_attr)
454 if (timer_dev_attr->timer_capability == OMAP_TIMER_SECURE)
457 pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
459 pr_err("%s: No memory for [%s]\n", __func__, oh->name);
464 * Extract the IDs from name field in hwmod database
465 * and use the same for constructing ids' for the
466 * timer devices. In a way, we are avoiding usage of
467 * static variable witin the function to do the same.
468 * CAUTION: We have to be careful and make sure the
469 * name in hwmod database does not change in which case
470 * we might either make corresponding change here or
471 * switch back static variable mechanism.
473 sscanf(oh->name, "timer%2d", &id);
475 pdata->set_timer_src = omap2_dm_timer_set_src;
476 pdata->timer_ip_version = oh->class->rev;
478 /* Mark clocksource and clockevent timers as reserved */
479 if ((sys_timer_reserved >> (id - 1)) & 0x1)
482 pdata->timer_errata = omap_dm_timer_get_errata();
483 pwrdm = omap_hwmod_get_pwrdm(oh);
484 pdata->loses_context = pwrdm_can_ever_lose_context(pwrdm);
486 pdata->get_context_loss_count = omap_pm_get_dev_context_loss_count;
488 pdev = omap_device_build(name, id, oh, pdata, sizeof(*pdata),
492 pr_err("%s: Can't build omap_device for %s: %s.\n",
493 __func__, name, oh->name);
503 * omap2_dm_timer_init - top level regular device initialization
505 * Uses dedicated hwmod api to parse through hwmod database for
506 * given class name and then build and register the timer device.
508 static int __init omap2_dm_timer_init(void)
512 ret = omap_hwmod_for_each_by_class("timer", omap_timer_init, NULL);
514 pr_err("%s: device registration failed.\n", __func__);
520 arch_initcall(omap2_dm_timer_init);