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/smp_twd.h>
43 #include <asm/sched_clock.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, 1);
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, 1, 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, 1);
121 __omap_dm_timer_load_start(&clkev,
122 OMAP_TIMER_CTRL_AR | OMAP_TIMER_CTRL_ST,
123 0xffffffff - period, 1);
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,
142 static int __init omap_dm_timer_init_one(struct omap_dm_timer *timer,
144 const char *fck_source)
146 char name[10]; /* 10 = sizeof("gptXX_Xck0") */
147 struct omap_hwmod *oh;
148 struct resource irq_rsrc, mem_rsrc;
153 sprintf(name, "timer%d", gptimer_id);
154 omap_hwmod_setup_one(name);
155 oh = omap_hwmod_lookup(name);
159 r = omap_hwmod_get_resource_byname(oh, IORESOURCE_IRQ, NULL, &irq_rsrc);
162 timer->irq = irq_rsrc.start;
164 r = omap_hwmod_get_resource_byname(oh, IORESOURCE_MEM, NULL, &mem_rsrc);
167 timer->phys_base = mem_rsrc.start;
168 size = mem_rsrc.end - mem_rsrc.start;
170 /* Static mapping, never released */
171 timer->io_base = ioremap(timer->phys_base, size);
175 /* After the dmtimer is using hwmod these clocks won't be needed */
176 sprintf(name, "gpt%d_fck", gptimer_id);
177 timer->fclk = clk_get(NULL, name);
178 if (IS_ERR(timer->fclk))
181 omap_hwmod_enable(oh);
183 sys_timer_reserved |= (1 << (gptimer_id - 1));
185 if (gptimer_id != 12) {
188 src = clk_get(NULL, fck_source);
192 res = __omap_dm_timer_set_source(timer->fclk, src);
193 if (IS_ERR_VALUE(res))
194 pr_warning("%s: timer%i cannot set source\n",
195 __func__, gptimer_id);
199 __omap_dm_timer_init_regs(timer);
200 __omap_dm_timer_reset(timer, 1, 1);
203 timer->rate = clk_get_rate(timer->fclk);
210 static void __init omap2_gp_clockevent_init(int gptimer_id,
211 const char *fck_source)
215 res = omap_dm_timer_init_one(&clkev, gptimer_id, fck_source);
218 omap2_gp_timer_irq.dev_id = (void *)&clkev;
219 setup_irq(clkev.irq, &omap2_gp_timer_irq);
221 __omap_dm_timer_int_enable(&clkev, OMAP_TIMER_INT_OVERFLOW);
223 clockevent_gpt.mult = div_sc(clkev.rate, NSEC_PER_SEC,
224 clockevent_gpt.shift);
225 clockevent_gpt.max_delta_ns =
226 clockevent_delta2ns(0xffffffff, &clockevent_gpt);
227 clockevent_gpt.min_delta_ns =
228 clockevent_delta2ns(3, &clockevent_gpt);
229 /* Timer internal resynch latency. */
231 clockevent_gpt.cpumask = cpumask_of(0);
232 clockevents_register_device(&clockevent_gpt);
234 pr_info("OMAP clockevent source: GPTIMER%d at %lu Hz\n",
235 gptimer_id, clkev.rate);
238 /* Clocksource code */
239 static struct omap_dm_timer clksrc;
240 static bool use_gptimer_clksrc;
245 static cycle_t clocksource_read_cycles(struct clocksource *cs)
247 return (cycle_t)__omap_dm_timer_read_counter(&clksrc, 1);
250 static struct clocksource clocksource_gpt = {
253 .read = clocksource_read_cycles,
254 .mask = CLOCKSOURCE_MASK(32),
255 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
258 static u32 notrace dmtimer_read_sched_clock(void)
261 return __omap_dm_timer_read_counter(&clksrc, 1);
266 /* Setup free-running counter for clocksource */
267 static int __init omap2_sync32k_clocksource_init(void)
270 struct omap_hwmod *oh;
272 const char *oh_name = "counter_32k";
275 * First check hwmod data is available for sync32k counter
277 oh = omap_hwmod_lookup(oh_name);
278 if (!oh || oh->slaves_cnt == 0)
281 omap_hwmod_setup_one(oh_name);
283 vbase = omap_hwmod_get_mpu_rt_va(oh);
285 pr_warn("%s: failed to get counter_32k resource\n", __func__);
289 ret = omap_hwmod_enable(oh);
291 pr_warn("%s: failed to enable counter_32k module (%d)\n",
296 ret = omap_init_clocksource_32k(vbase);
298 pr_warn("%s: failed to initialize counter_32k as a clocksource (%d)\n",
306 static void __init omap2_gptimer_clocksource_init(int gptimer_id,
307 const char *fck_source)
311 res = omap_dm_timer_init_one(&clksrc, gptimer_id, fck_source);
314 __omap_dm_timer_load_start(&clksrc,
315 OMAP_TIMER_CTRL_ST | OMAP_TIMER_CTRL_AR, 0, 1);
316 setup_sched_clock(dmtimer_read_sched_clock, 32, clksrc.rate);
318 if (clocksource_register_hz(&clocksource_gpt, clksrc.rate))
319 pr_err("Could not register clocksource %s\n",
320 clocksource_gpt.name);
322 pr_info("OMAP clocksource: GPTIMER%d at %lu Hz\n",
323 gptimer_id, clksrc.rate);
326 static void __init omap2_clocksource_init(int gptimer_id,
327 const char *fck_source)
330 * First give preference to kernel parameter configuration
331 * by user (clocksource="gp_timer").
333 * In case of missing kernel parameter for clocksource,
334 * first check for availability for 32k-sync timer, in case
335 * of failure in finding 32k_counter module or registering
336 * it as clocksource, execution will fallback to gp-timer.
338 if (use_gptimer_clksrc == true)
339 omap2_gptimer_clocksource_init(gptimer_id, fck_source);
340 else if (omap2_sync32k_clocksource_init())
341 /* Fall back to gp-timer code */
342 omap2_gptimer_clocksource_init(gptimer_id, fck_source);
345 #define OMAP_SYS_TIMER_INIT(name, clkev_nr, clkev_src, \
346 clksrc_nr, clksrc_src) \
347 static void __init omap##name##_timer_init(void) \
349 omap2_gp_clockevent_init((clkev_nr), clkev_src); \
350 omap2_clocksource_init((clksrc_nr), clksrc_src); \
353 #define OMAP_SYS_TIMER(name) \
354 struct sys_timer omap##name##_timer = { \
355 .init = omap##name##_timer_init, \
358 #ifdef CONFIG_ARCH_OMAP2
359 OMAP_SYS_TIMER_INIT(2, 1, OMAP2_CLKEV_SOURCE, 2, OMAP2_MPU_SOURCE)
363 #ifdef CONFIG_ARCH_OMAP3
364 OMAP_SYS_TIMER_INIT(3, 1, OMAP3_CLKEV_SOURCE, 2, OMAP3_MPU_SOURCE)
366 OMAP_SYS_TIMER_INIT(3_secure, OMAP3_SECURE_TIMER, OMAP3_CLKEV_SOURCE,
368 OMAP_SYS_TIMER(3_secure)
371 #ifdef CONFIG_ARCH_OMAP4
372 #ifdef CONFIG_LOCAL_TIMERS
373 static DEFINE_TWD_LOCAL_TIMER(twd_local_timer,
374 OMAP44XX_LOCAL_TWD_BASE,
375 OMAP44XX_IRQ_LOCALTIMER);
378 static void __init omap4_timer_init(void)
380 omap2_gp_clockevent_init(1, OMAP4_CLKEV_SOURCE);
381 omap2_clocksource_init(2, OMAP4_MPU_SOURCE);
382 #ifdef CONFIG_LOCAL_TIMERS
383 /* Local timers are not supprted on OMAP4430 ES1.0 */
384 if (omap_rev() != OMAP4430_REV_ES1_0) {
387 err = twd_local_timer_register(&twd_local_timer);
389 pr_err("twd_local_timer_register failed %d\n", err);
397 * omap2_dm_timer_set_src - change the timer input clock source
398 * @pdev: timer platform device pointer
399 * @source: array index of parent clock source
401 static int omap2_dm_timer_set_src(struct platform_device *pdev, int source)
404 struct dmtimer_platform_data *pdata = pdev->dev.platform_data;
405 struct clk *fclk, *parent;
406 char *parent_name = NULL;
408 fclk = clk_get(&pdev->dev, "fck");
409 if (IS_ERR_OR_NULL(fclk)) {
410 dev_err(&pdev->dev, "%s: %d: clk_get() FAILED\n",
416 case OMAP_TIMER_SRC_SYS_CLK:
417 parent_name = "sys_ck";
420 case OMAP_TIMER_SRC_32_KHZ:
421 parent_name = "32k_ck";
424 case OMAP_TIMER_SRC_EXT_CLK:
425 if (pdata->timer_ip_version == OMAP_TIMER_IP_VERSION_1) {
426 parent_name = "alt_ck";
429 dev_err(&pdev->dev, "%s: %d: invalid clk src.\n",
435 parent = clk_get(&pdev->dev, parent_name);
436 if (IS_ERR_OR_NULL(parent)) {
437 dev_err(&pdev->dev, "%s: %d: clk_get() %s FAILED\n",
438 __func__, __LINE__, parent_name);
443 ret = clk_set_parent(fclk, parent);
444 if (IS_ERR_VALUE(ret)) {
445 dev_err(&pdev->dev, "%s: clk_set_parent() to %s FAILED\n",
446 __func__, parent_name);
457 * omap_timer_init - build and register timer device with an
458 * associated timer hwmod
459 * @oh: timer hwmod pointer to be used to build timer device
460 * @user: parameter that can be passed from calling hwmod API
462 * Called by omap_hwmod_for_each_by_class to register each of the timer
463 * devices present in the system. The number of timer devices is known
464 * by parsing through the hwmod database for a given class name. At the
465 * end of function call memory is allocated for timer device and it is
466 * registered to the framework ready to be proved by the driver.
468 static int __init omap_timer_init(struct omap_hwmod *oh, void *unused)
472 char *name = "omap_timer";
473 struct dmtimer_platform_data *pdata;
474 struct platform_device *pdev;
475 struct omap_timer_capability_dev_attr *timer_dev_attr;
476 struct powerdomain *pwrdm;
478 pr_debug("%s: %s\n", __func__, oh->name);
480 /* on secure device, do not register secure timer */
481 timer_dev_attr = oh->dev_attr;
482 if (omap_type() != OMAP2_DEVICE_TYPE_GP && timer_dev_attr)
483 if (timer_dev_attr->timer_capability == OMAP_TIMER_SECURE)
486 pdata = kzalloc(sizeof(*pdata), GFP_KERNEL);
488 pr_err("%s: No memory for [%s]\n", __func__, oh->name);
493 * Extract the IDs from name field in hwmod database
494 * and use the same for constructing ids' for the
495 * timer devices. In a way, we are avoiding usage of
496 * static variable witin the function to do the same.
497 * CAUTION: We have to be careful and make sure the
498 * name in hwmod database does not change in which case
499 * we might either make corresponding change here or
500 * switch back static variable mechanism.
502 sscanf(oh->name, "timer%2d", &id);
504 pdata->set_timer_src = omap2_dm_timer_set_src;
505 pdata->timer_ip_version = oh->class->rev;
507 /* Mark clocksource and clockevent timers as reserved */
508 if ((sys_timer_reserved >> (id - 1)) & 0x1)
511 pwrdm = omap_hwmod_get_pwrdm(oh);
512 pdata->loses_context = pwrdm_can_ever_lose_context(pwrdm);
514 pdata->get_context_loss_count = omap_pm_get_dev_context_loss_count;
516 pdev = omap_device_build(name, id, oh, pdata, sizeof(*pdata),
520 pr_err("%s: Can't build omap_device for %s: %s.\n",
521 __func__, name, oh->name);
531 * omap2_dm_timer_init - top level regular device initialization
533 * Uses dedicated hwmod api to parse through hwmod database for
534 * given class name and then build and register the timer device.
536 static int __init omap2_dm_timer_init(void)
540 ret = omap_hwmod_for_each_by_class("timer", omap_timer_init, NULL);
542 pr_err("%s: device registration failed.\n", __func__);
548 arch_initcall(omap2_dm_timer_init);
551 * omap2_override_clocksource - clocksource override with user configuration
553 * Allows user to override default clocksource, using kernel parameter
554 * clocksource="gp_timer" (For all OMAP2PLUS architectures)
556 * Note that, here we are using same standard kernel parameter "clocksource=",
557 * and not introducing any OMAP specific interface.
559 static int __init omap2_override_clocksource(char *str)
564 * For OMAP architecture, we only have two options
565 * - sync_32k (default)
566 * - gp_timer (sys_clk based)
568 if (!strcmp(str, "gp_timer"))
569 use_gptimer_clksrc = true;
573 early_param("clocksource", omap2_override_clocksource);