USB: serial: option: reimplement interface masking
[linux/fpc-iii.git] / arch / arm / mach-omap2 / timer.c
blobece09c9461f78d9b3908095615a688522b69e9b3
1 /*
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.
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
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
27 * for more details.
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>
39 #include <linux/of.h>
40 #include <linux/of_address.h>
41 #include <linux/of_irq.h>
42 #include <linux/platform_device.h>
43 #include <linux/platform_data/dmtimer-omap.h>
44 #include <linux/sched_clock.h>
46 #include <asm/mach/time.h>
47 #include <asm/smp_twd.h>
49 #include "omap_hwmod.h"
50 #include "omap_device.h"
51 #include <plat/counter-32k.h>
52 #include <plat/dmtimer.h>
53 #include "omap-pm.h"
55 #include "soc.h"
56 #include "common.h"
57 #include "control.h"
58 #include "powerdomain.h"
59 #include "omap-secure.h"
61 #define REALTIME_COUNTER_BASE 0x48243200
62 #define INCREMENTER_NUMERATOR_OFFSET 0x10
63 #define INCREMENTER_DENUMERATOR_RELOAD_OFFSET 0x14
64 #define NUMERATOR_DENUMERATOR_MASK 0xfffff000
66 /* Clockevent code */
68 static struct omap_dm_timer clkev;
69 static struct clock_event_device clockevent_gpt;
71 /* Clockevent hwmod for am335x and am437x suspend */
72 static struct omap_hwmod *clockevent_gpt_hwmod;
74 #ifdef CONFIG_SOC_HAS_REALTIME_COUNTER
75 static unsigned long arch_timer_freq;
77 void set_cntfreq(void)
79 omap_smc1(OMAP5_DRA7_MON_SET_CNTFRQ_INDEX, arch_timer_freq);
81 #endif
83 static irqreturn_t omap2_gp_timer_interrupt(int irq, void *dev_id)
85 struct clock_event_device *evt = &clockevent_gpt;
87 __omap_dm_timer_write_status(&clkev, OMAP_TIMER_INT_OVERFLOW);
89 evt->event_handler(evt);
90 return IRQ_HANDLED;
93 static struct irqaction omap2_gp_timer_irq = {
94 .name = "gp_timer",
95 .flags = IRQF_TIMER | IRQF_IRQPOLL,
96 .handler = omap2_gp_timer_interrupt,
99 static int omap2_gp_timer_set_next_event(unsigned long cycles,
100 struct clock_event_device *evt)
102 __omap_dm_timer_load_start(&clkev, OMAP_TIMER_CTRL_ST,
103 0xffffffff - cycles, OMAP_TIMER_POSTED);
105 return 0;
108 static int omap2_gp_timer_shutdown(struct clock_event_device *evt)
110 __omap_dm_timer_stop(&clkev, OMAP_TIMER_POSTED, clkev.rate);
111 return 0;
114 static int omap2_gp_timer_set_periodic(struct clock_event_device *evt)
116 u32 period;
118 __omap_dm_timer_stop(&clkev, OMAP_TIMER_POSTED, clkev.rate);
120 period = clkev.rate / HZ;
121 period -= 1;
122 /* Looks like we need to first set the load value separately */
123 __omap_dm_timer_write(&clkev, OMAP_TIMER_LOAD_REG, 0xffffffff - period,
124 OMAP_TIMER_POSTED);
125 __omap_dm_timer_load_start(&clkev,
126 OMAP_TIMER_CTRL_AR | OMAP_TIMER_CTRL_ST,
127 0xffffffff - period, OMAP_TIMER_POSTED);
128 return 0;
131 static void omap_clkevt_idle(struct clock_event_device *unused)
133 if (!clockevent_gpt_hwmod)
134 return;
136 omap_hwmod_idle(clockevent_gpt_hwmod);
139 static void omap_clkevt_unidle(struct clock_event_device *unused)
141 if (!clockevent_gpt_hwmod)
142 return;
144 omap_hwmod_enable(clockevent_gpt_hwmod);
145 __omap_dm_timer_int_enable(&clkev, OMAP_TIMER_INT_OVERFLOW);
148 static struct clock_event_device clockevent_gpt = {
149 .features = CLOCK_EVT_FEAT_PERIODIC |
150 CLOCK_EVT_FEAT_ONESHOT,
151 .rating = 300,
152 .set_next_event = omap2_gp_timer_set_next_event,
153 .set_state_shutdown = omap2_gp_timer_shutdown,
154 .set_state_periodic = omap2_gp_timer_set_periodic,
155 .set_state_oneshot = omap2_gp_timer_shutdown,
156 .tick_resume = omap2_gp_timer_shutdown,
159 static struct property device_disabled = {
160 .name = "status",
161 .length = sizeof("disabled"),
162 .value = "disabled",
165 static const struct of_device_id omap_timer_match[] __initconst = {
166 { .compatible = "ti,omap2420-timer", },
167 { .compatible = "ti,omap3430-timer", },
168 { .compatible = "ti,omap4430-timer", },
169 { .compatible = "ti,omap5430-timer", },
170 { .compatible = "ti,dm814-timer", },
171 { .compatible = "ti,dm816-timer", },
172 { .compatible = "ti,am335x-timer", },
173 { .compatible = "ti,am335x-timer-1ms", },
178 * omap_get_timer_dt - get a timer using device-tree
179 * @match - device-tree match structure for matching a device type
180 * @property - optional timer property to match
182 * Helper function to get a timer during early boot using device-tree for use
183 * as kernel system timer. Optionally, the property argument can be used to
184 * select a timer with a specific property. Once a timer is found then mark
185 * the timer node in device-tree as disabled, to prevent the kernel from
186 * registering this timer as a platform device and so no one else can use it.
188 static struct device_node * __init omap_get_timer_dt(const struct of_device_id *match,
189 const char *property)
191 struct device_node *np;
193 for_each_matching_node(np, match) {
194 if (!of_device_is_available(np))
195 continue;
197 if (property && !of_get_property(np, property, NULL))
198 continue;
200 if (!property && (of_get_property(np, "ti,timer-alwon", NULL) ||
201 of_get_property(np, "ti,timer-dsp", NULL) ||
202 of_get_property(np, "ti,timer-pwm", NULL) ||
203 of_get_property(np, "ti,timer-secure", NULL)))
204 continue;
206 if (!of_device_is_compatible(np, "ti,omap-counter32k"))
207 of_add_property(np, &device_disabled);
208 return np;
211 return NULL;
215 * omap_dmtimer_init - initialisation function when device tree is used
217 * For secure OMAP3/DRA7xx devices, timers with device type "timer-secure"
218 * cannot be used by the kernel as they are reserved. Therefore, to prevent the
219 * kernel registering these devices remove them dynamically from the device
220 * tree on boot.
222 static void __init omap_dmtimer_init(void)
224 struct device_node *np;
226 if (!cpu_is_omap34xx() && !soc_is_dra7xx())
227 return;
229 /* If we are a secure device, remove any secure timer nodes */
230 if ((omap_type() != OMAP2_DEVICE_TYPE_GP)) {
231 np = omap_get_timer_dt(omap_timer_match, "ti,timer-secure");
232 of_node_put(np);
237 * omap_dm_timer_get_errata - get errata flags for a timer
239 * Get the timer errata flags that are specific to the OMAP device being used.
241 static u32 __init omap_dm_timer_get_errata(void)
243 if (cpu_is_omap24xx())
244 return 0;
246 return OMAP_TIMER_ERRATA_I103_I767;
249 static int __init omap_dm_timer_init_one(struct omap_dm_timer *timer,
250 const char *fck_source,
251 const char *property,
252 const char **timer_name,
253 int posted)
255 const char *oh_name = NULL;
256 struct device_node *np;
257 struct omap_hwmod *oh;
258 struct clk *src;
259 int r = 0;
261 np = omap_get_timer_dt(omap_timer_match, property);
262 if (!np)
263 return -ENODEV;
265 of_property_read_string_index(np, "ti,hwmods", 0, &oh_name);
266 if (!oh_name)
267 return -ENODEV;
269 timer->irq = irq_of_parse_and_map(np, 0);
270 if (!timer->irq)
271 return -ENXIO;
273 timer->io_base = of_iomap(np, 0);
275 timer->fclk = of_clk_get_by_name(np, "fck");
277 of_node_put(np);
279 oh = omap_hwmod_lookup(oh_name);
280 if (!oh)
281 return -ENODEV;
283 *timer_name = oh->name;
285 if (!timer->io_base)
286 return -ENXIO;
288 omap_hwmod_setup_one(oh_name);
290 /* After the dmtimer is using hwmod these clocks won't be needed */
291 if (IS_ERR_OR_NULL(timer->fclk))
292 timer->fclk = clk_get(NULL, omap_hwmod_get_main_clk(oh));
293 if (IS_ERR(timer->fclk))
294 return PTR_ERR(timer->fclk);
296 src = clk_get(NULL, fck_source);
297 if (IS_ERR(src))
298 return PTR_ERR(src);
300 WARN(clk_set_parent(timer->fclk, src) < 0,
301 "Cannot set timer parent clock, no PLL clock driver?");
303 clk_put(src);
305 omap_hwmod_enable(oh);
306 __omap_dm_timer_init_regs(timer);
308 if (posted)
309 __omap_dm_timer_enable_posted(timer);
311 /* Check that the intended posted configuration matches the actual */
312 if (posted != timer->posted)
313 return -EINVAL;
315 timer->rate = clk_get_rate(timer->fclk);
316 timer->reserved = 1;
318 return r;
321 #if !defined(CONFIG_SMP) && defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST)
322 void tick_broadcast(const struct cpumask *mask)
325 #endif
327 static void __init omap2_gp_clockevent_init(int gptimer_id,
328 const char *fck_source,
329 const char *property)
331 int res;
333 clkev.id = gptimer_id;
334 clkev.errata = omap_dm_timer_get_errata();
337 * For clock-event timers we never read the timer counter and
338 * so we are not impacted by errata i103 and i767. Therefore,
339 * we can safely ignore this errata for clock-event timers.
341 __omap_dm_timer_override_errata(&clkev, OMAP_TIMER_ERRATA_I103_I767);
343 res = omap_dm_timer_init_one(&clkev, fck_source, property,
344 &clockevent_gpt.name, OMAP_TIMER_POSTED);
345 BUG_ON(res);
347 omap2_gp_timer_irq.dev_id = &clkev;
348 setup_irq(clkev.irq, &omap2_gp_timer_irq);
350 __omap_dm_timer_int_enable(&clkev, OMAP_TIMER_INT_OVERFLOW);
352 clockevent_gpt.cpumask = cpu_possible_mask;
353 clockevent_gpt.irq = omap_dm_timer_get_irq(&clkev);
354 clockevents_config_and_register(&clockevent_gpt, clkev.rate,
355 3, /* Timer internal resynch latency */
356 0xffffffff);
358 if (soc_is_am33xx() || soc_is_am43xx()) {
359 clockevent_gpt.suspend = omap_clkevt_idle;
360 clockevent_gpt.resume = omap_clkevt_unidle;
362 clockevent_gpt_hwmod =
363 omap_hwmod_lookup(clockevent_gpt.name);
366 pr_info("OMAP clockevent source: %s at %lu Hz\n", clockevent_gpt.name,
367 clkev.rate);
370 /* Clocksource code */
371 static struct omap_dm_timer clksrc;
372 static bool use_gptimer_clksrc __initdata;
375 * clocksource
377 static u64 clocksource_read_cycles(struct clocksource *cs)
379 return (u64)__omap_dm_timer_read_counter(&clksrc,
380 OMAP_TIMER_NONPOSTED);
383 static struct clocksource clocksource_gpt = {
384 .rating = 300,
385 .read = clocksource_read_cycles,
386 .mask = CLOCKSOURCE_MASK(32),
387 .flags = CLOCK_SOURCE_IS_CONTINUOUS,
390 static u64 notrace dmtimer_read_sched_clock(void)
392 if (clksrc.reserved)
393 return __omap_dm_timer_read_counter(&clksrc,
394 OMAP_TIMER_NONPOSTED);
396 return 0;
399 static const struct of_device_id omap_counter_match[] __initconst = {
400 { .compatible = "ti,omap-counter32k", },
404 /* Setup free-running counter for clocksource */
405 static int __init __maybe_unused omap2_sync32k_clocksource_init(void)
407 int ret;
408 struct device_node *np = NULL;
409 struct omap_hwmod *oh;
410 const char *oh_name = "counter_32k";
413 * See if the 32kHz counter is supported.
415 np = omap_get_timer_dt(omap_counter_match, NULL);
416 if (!np)
417 return -ENODEV;
419 of_property_read_string_index(np, "ti,hwmods", 0, &oh_name);
420 if (!oh_name)
421 return -ENODEV;
424 * First check hwmod data is available for sync32k counter
426 oh = omap_hwmod_lookup(oh_name);
427 if (!oh || oh->slaves_cnt == 0)
428 return -ENODEV;
430 omap_hwmod_setup_one(oh_name);
432 ret = omap_hwmod_enable(oh);
433 if (ret) {
434 pr_warn("%s: failed to enable counter_32k module (%d)\n",
435 __func__, ret);
436 return ret;
439 return ret;
442 static void __init omap2_gptimer_clocksource_init(int gptimer_id,
443 const char *fck_source,
444 const char *property)
446 int res;
448 clksrc.id = gptimer_id;
449 clksrc.errata = omap_dm_timer_get_errata();
451 res = omap_dm_timer_init_one(&clksrc, fck_source, property,
452 &clocksource_gpt.name,
453 OMAP_TIMER_NONPOSTED);
454 BUG_ON(res);
456 __omap_dm_timer_load_start(&clksrc,
457 OMAP_TIMER_CTRL_ST | OMAP_TIMER_CTRL_AR, 0,
458 OMAP_TIMER_NONPOSTED);
459 sched_clock_register(dmtimer_read_sched_clock, 32, clksrc.rate);
461 if (clocksource_register_hz(&clocksource_gpt, clksrc.rate))
462 pr_err("Could not register clocksource %s\n",
463 clocksource_gpt.name);
464 else
465 pr_info("OMAP clocksource: %s at %lu Hz\n",
466 clocksource_gpt.name, clksrc.rate);
469 static void __init __omap_sync32k_timer_init(int clkev_nr, const char *clkev_src,
470 const char *clkev_prop, int clksrc_nr, const char *clksrc_src,
471 const char *clksrc_prop, bool gptimer)
473 omap_clk_init();
474 omap_dmtimer_init();
475 omap2_gp_clockevent_init(clkev_nr, clkev_src, clkev_prop);
477 /* Enable the use of clocksource="gp_timer" kernel parameter */
478 if (use_gptimer_clksrc || gptimer)
479 omap2_gptimer_clocksource_init(clksrc_nr, clksrc_src,
480 clksrc_prop);
481 else
482 omap2_sync32k_clocksource_init();
485 void __init omap_init_time(void)
487 __omap_sync32k_timer_init(1, "timer_32k_ck", "ti,timer-alwon",
488 2, "timer_sys_ck", NULL, false);
490 timer_probe();
493 #if defined(CONFIG_ARCH_OMAP3) || defined(CONFIG_SOC_AM43XX)
494 void __init omap3_secure_sync32k_timer_init(void)
496 __omap_sync32k_timer_init(12, "secure_32k_fck", "ti,timer-secure",
497 2, "timer_sys_ck", NULL, false);
499 timer_probe();
501 #endif /* CONFIG_ARCH_OMAP3 */
503 #if defined(CONFIG_ARCH_OMAP3) || defined(CONFIG_SOC_AM33XX) || \
504 defined(CONFIG_SOC_AM43XX)
505 void __init omap3_gptimer_timer_init(void)
507 __omap_sync32k_timer_init(2, "timer_sys_ck", NULL,
508 1, "timer_sys_ck", "ti,timer-alwon", true);
509 if (of_have_populated_dt())
510 timer_probe();
512 #endif
514 #if defined(CONFIG_ARCH_OMAP4) || defined(CONFIG_SOC_OMAP5) || \
515 defined(CONFIG_SOC_DRA7XX)
516 static void __init omap4_sync32k_timer_init(void)
518 __omap_sync32k_timer_init(1, "timer_32k_ck", "ti,timer-alwon",
519 2, "sys_clkin_ck", NULL, false);
522 void __init omap4_local_timer_init(void)
524 omap4_sync32k_timer_init();
525 timer_probe();
527 #endif
529 #if defined(CONFIG_SOC_OMAP5) || defined(CONFIG_SOC_DRA7XX)
532 * The realtime counter also called master counter, is a free-running
533 * counter, which is related to real time. It produces the count used
534 * by the CPU local timer peripherals in the MPU cluster. The timer counts
535 * at a rate of 6.144 MHz. Because the device operates on different clocks
536 * in different power modes, the master counter shifts operation between
537 * clocks, adjusting the increment per clock in hardware accordingly to
538 * maintain a constant count rate.
540 static void __init realtime_counter_init(void)
542 #ifdef CONFIG_SOC_HAS_REALTIME_COUNTER
543 void __iomem *base;
544 static struct clk *sys_clk;
545 unsigned long rate;
546 unsigned int reg;
547 unsigned long long num, den;
549 base = ioremap(REALTIME_COUNTER_BASE, SZ_32);
550 if (!base) {
551 pr_err("%s: ioremap failed\n", __func__);
552 return;
554 sys_clk = clk_get(NULL, "sys_clkin");
555 if (IS_ERR(sys_clk)) {
556 pr_err("%s: failed to get system clock handle\n", __func__);
557 iounmap(base);
558 return;
561 rate = clk_get_rate(sys_clk);
563 if (soc_is_dra7xx()) {
565 * Errata i856 says the 32.768KHz crystal does not start at
566 * power on, so the CPU falls back to an emulated 32KHz clock
567 * based on sysclk / 610 instead. This causes the master counter
568 * frequency to not be 6.144MHz but at sysclk / 610 * 375 / 2
569 * (OR sysclk * 75 / 244)
571 * This affects at least the DRA7/AM572x 1.0, 1.1 revisions.
572 * Of course any board built without a populated 32.768KHz
573 * crystal would also need this fix even if the CPU is fixed
574 * later.
576 * Either case can be detected by using the two speedselect bits
577 * If they are not 0, then the 32.768KHz clock driving the
578 * coarse counter that corrects the fine counter every time it
579 * ticks is actually rate/610 rather than 32.768KHz and we
580 * should compensate to avoid the 570ppm (at 20MHz, much worse
581 * at other rates) too fast system time.
583 reg = omap_ctrl_readl(DRA7_CTRL_CORE_BOOTSTRAP);
584 if (reg & DRA7_SPEEDSELECT_MASK) {
585 num = 75;
586 den = 244;
587 goto sysclk1_based;
591 /* Numerator/denumerator values refer TRM Realtime Counter section */
592 switch (rate) {
593 case 12000000:
594 num = 64;
595 den = 125;
596 break;
597 case 13000000:
598 num = 768;
599 den = 1625;
600 break;
601 case 19200000:
602 num = 8;
603 den = 25;
604 break;
605 case 20000000:
606 num = 192;
607 den = 625;
608 break;
609 case 26000000:
610 num = 384;
611 den = 1625;
612 break;
613 case 27000000:
614 num = 256;
615 den = 1125;
616 break;
617 case 38400000:
618 default:
619 /* Program it for 38.4 MHz */
620 num = 4;
621 den = 25;
622 break;
625 sysclk1_based:
626 /* Program numerator and denumerator registers */
627 reg = readl_relaxed(base + INCREMENTER_NUMERATOR_OFFSET) &
628 NUMERATOR_DENUMERATOR_MASK;
629 reg |= num;
630 writel_relaxed(reg, base + INCREMENTER_NUMERATOR_OFFSET);
632 reg = readl_relaxed(base + INCREMENTER_DENUMERATOR_RELOAD_OFFSET) &
633 NUMERATOR_DENUMERATOR_MASK;
634 reg |= den;
635 writel_relaxed(reg, base + INCREMENTER_DENUMERATOR_RELOAD_OFFSET);
637 arch_timer_freq = DIV_ROUND_UP_ULL(rate * num, den);
638 set_cntfreq();
640 iounmap(base);
641 #endif
644 void __init omap5_realtime_timer_init(void)
646 omap4_sync32k_timer_init();
647 realtime_counter_init();
649 timer_probe();
651 #endif /* CONFIG_SOC_OMAP5 || CONFIG_SOC_DRA7XX */
654 * omap2_override_clocksource - clocksource override with user configuration
656 * Allows user to override default clocksource, using kernel parameter
657 * clocksource="gp_timer" (For all OMAP2PLUS architectures)
659 * Note that, here we are using same standard kernel parameter "clocksource=",
660 * and not introducing any OMAP specific interface.
662 static int __init omap2_override_clocksource(char *str)
664 if (!str)
665 return 0;
667 * For OMAP architecture, we only have two options
668 * - sync_32k (default)
669 * - gp_timer (sys_clk based)
671 if (!strcmp(str, "gp_timer"))
672 use_gptimer_clksrc = true;
674 return 0;
676 early_param("clocksource", omap2_override_clocksource);