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v3.1
  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,
297			OMAP_TIMER_CTRL_ST | OMAP_TIMER_CTRL_AR, 0, 1);
298	init_sched_clock(&cd, dmtimer_update_sched_clock, 32, clksrc.rate);
 
299
300	if (clocksource_register_hz(&clocksource_gpt, clksrc.rate))
301		pr_err("Could not register clocksource %s\n",
302			clocksource_gpt.name);
 
 
 
303}
304#endif
305
306#define OMAP_SYS_TIMER_INIT(name, clkev_nr, clkev_src,			\
307				clksrc_nr, clksrc_src)			\
308static void __init omap##name##_timer_init(void)			\
309{									\
310	omap2_gp_clockevent_init((clkev_nr), clkev_src);		\
311	omap2_gp_clocksource_init((clksrc_nr), clksrc_src);		\
 
 
 
 
 
 
 
 
312}
313
314#define OMAP_SYS_TIMER(name)						\
315struct sys_timer omap##name##_timer = {					\
316	.init	= omap##name##_timer_init,				\
317};
 
 
 
 
 
 
 
 
 
318
319#ifdef CONFIG_ARCH_OMAP2
320OMAP_SYS_TIMER_INIT(2, 1, OMAP2_CLKEV_SOURCE, 2, OMAP2_MPU_SOURCE)
321OMAP_SYS_TIMER(2)
 
 
 
 
 
 
 
 
 
 
322#endif
323
324#ifdef CONFIG_ARCH_OMAP3
325OMAP_SYS_TIMER_INIT(3, 1, OMAP3_CLKEV_SOURCE, 2, OMAP3_MPU_SOURCE)
326OMAP_SYS_TIMER(3)
327OMAP_SYS_TIMER_INIT(3_secure, OMAP3_SECURE_TIMER, OMAP3_CLKEV_SOURCE,
328			2, OMAP3_MPU_SOURCE)
329OMAP_SYS_TIMER(3_secure)
 
 
 
 
 
 
 
330#endif
331
332#ifdef CONFIG_ARCH_OMAP4
333static void __init omap4_timer_init(void)
 
 
 
 
 
 
 
 
 
 
334{
335#ifdef CONFIG_LOCAL_TIMERS
336	twd_base = ioremap(OMAP44XX_LOCAL_TWD_BASE, SZ_256);
337	BUG_ON(!twd_base);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
338#endif
339	omap2_gp_clockevent_init(1, OMAP4_CLKEV_SOURCE);
340	omap2_gp_clocksource_init(2, OMAP4_MPU_SOURCE);
341}
342OMAP_SYS_TIMER(4)
343#endif
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
v4.17
  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#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>
 45
 46#include <asm/mach/time.h>
 47#include <asm/smp_twd.h>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 48
 49#include "omap_hwmod.h"
 50#include "omap_device.h"
 51#include <plat/counter-32k.h>
 52#include <clocksource/timer-ti-dm.h>
 53#include "omap-pm.h"
 54
 55#include "soc.h"
 56#include "common.h"
 57#include "control.h"
 58#include "powerdomain.h"
 59#include "omap-secure.h"
 60
 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
 65
 66/* Clockevent code */
 67
 68static struct omap_dm_timer clkev;
 69static struct clock_event_device clockevent_gpt;
 70
 71/* Clockevent hwmod for am335x and am437x suspend */
 72static struct omap_hwmod *clockevent_gpt_hwmod;
 73
 74#ifdef CONFIG_SOC_HAS_REALTIME_COUNTER
 75static unsigned long arch_timer_freq;
 76
 77void set_cntfreq(void)
 78{
 79	omap_smc1(OMAP5_DRA7_MON_SET_CNTFRQ_INDEX, arch_timer_freq);
 80}
 81#endif
 82
 83static irqreturn_t omap2_gp_timer_interrupt(int irq, void *dev_id)
 84{
 85	struct clock_event_device *evt = &clockevent_gpt;
 86
 87	__omap_dm_timer_write_status(&clkev, OMAP_TIMER_INT_OVERFLOW);
 88
 89	evt->event_handler(evt);
 90	return IRQ_HANDLED;
 91}
 92
 93static struct irqaction omap2_gp_timer_irq = {
 94	.name		= "gp_timer",
 95	.flags		= IRQF_TIMER | IRQF_IRQPOLL,
 96	.handler	= omap2_gp_timer_interrupt,
 97};
 98
 99static int omap2_gp_timer_set_next_event(unsigned long cycles,
100					 struct clock_event_device *evt)
101{
102	__omap_dm_timer_load_start(&clkev, OMAP_TIMER_CTRL_ST,
103				   0xffffffff - cycles, OMAP_TIMER_POSTED);
104
105	return 0;
106}
107
108static int omap2_gp_timer_shutdown(struct clock_event_device *evt)
109{
110	__omap_dm_timer_stop(&clkev, OMAP_TIMER_POSTED, clkev.rate);
111	return 0;
112}
113
114static int omap2_gp_timer_set_periodic(struct clock_event_device *evt)
115{
116	u32 period;
117
118	__omap_dm_timer_stop(&clkev, OMAP_TIMER_POSTED, clkev.rate);
119
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;
129}
130
131static void omap_clkevt_idle(struct clock_event_device *unused)
132{
133	if (!clockevent_gpt_hwmod)
134		return;
135
136	omap_hwmod_idle(clockevent_gpt_hwmod);
137}
138
139static void omap_clkevt_unidle(struct clock_event_device *unused)
140{
141	if (!clockevent_gpt_hwmod)
142		return;
143
144	omap_hwmod_enable(clockevent_gpt_hwmod);
145	__omap_dm_timer_int_enable(&clkev, OMAP_TIMER_INT_OVERFLOW);
146}
147
148static 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,
157};
158
159static const struct of_device_id omap_timer_match[] __initconst = {
160	{ .compatible = "ti,omap2420-timer", },
161	{ .compatible = "ti,omap3430-timer", },
162	{ .compatible = "ti,omap4430-timer", },
163	{ .compatible = "ti,omap5430-timer", },
164	{ .compatible = "ti,dm814-timer", },
165	{ .compatible = "ti,dm816-timer", },
166	{ .compatible = "ti,am335x-timer", },
167	{ .compatible = "ti,am335x-timer-1ms", },
168	{ }
169};
170
171/**
172 * omap_get_timer_dt - get a timer using device-tree
173 * @match	- device-tree match structure for matching a device type
174 * @property	- optional timer property to match
175 *
176 * Helper function to get a timer during early boot using device-tree for use
177 * as kernel system timer. Optionally, the property argument can be used to
178 * select a timer with a specific property. Once a timer is found then mark
179 * the timer node in device-tree as disabled, to prevent the kernel from
180 * registering this timer as a platform device and so no one else can use it.
181 */
182static struct device_node * __init omap_get_timer_dt(const struct of_device_id *match,
183						     const char *property)
184{
185	struct device_node *np;
186
187	for_each_matching_node(np, match) {
188		if (!of_device_is_available(np))
189			continue;
190
191		if (property && !of_get_property(np, property, NULL))
192			continue;
193
194		if (!property && (of_get_property(np, "ti,timer-alwon", NULL) ||
195				  of_get_property(np, "ti,timer-dsp", NULL) ||
196				  of_get_property(np, "ti,timer-pwm", NULL) ||
197				  of_get_property(np, "ti,timer-secure", NULL)))
198			continue;
199
200		if (!of_device_is_compatible(np, "ti,omap-counter32k")) {
201			struct property *prop;
202
203			prop = kzalloc(sizeof(*prop), GFP_KERNEL);
204			if (!prop)
205				return NULL;
206			prop->name = "status";
207			prop->value = "disabled";
208			prop->length = strlen(prop->value);
209			of_add_property(np, prop);
210		}
211		return np;
212	}
213
214	return NULL;
215}
216
217/**
218 * omap_dmtimer_init - initialisation function when device tree is used
219 *
220 * For secure OMAP3/DRA7xx devices, timers with device type "timer-secure"
221 * cannot be used by the kernel as they are reserved. Therefore, to prevent the
222 * kernel registering these devices remove them dynamically from the device
223 * tree on boot.
224 */
225static void __init omap_dmtimer_init(void)
226{
227	struct device_node *np;
228
229	if (!cpu_is_omap34xx() && !soc_is_dra7xx())
230		return;
231
232	/* If we are a secure device, remove any secure timer nodes */
233	if ((omap_type() != OMAP2_DEVICE_TYPE_GP)) {
234		np = omap_get_timer_dt(omap_timer_match, "ti,timer-secure");
235		of_node_put(np);
236	}
237}
238
239/**
240 * omap_dm_timer_get_errata - get errata flags for a timer
241 *
242 * Get the timer errata flags that are specific to the OMAP device being used.
243 */
244static u32 __init omap_dm_timer_get_errata(void)
245{
246	if (cpu_is_omap24xx())
247		return 0;
248
249	return OMAP_TIMER_ERRATA_I103_I767;
250}
251
252static int __init omap_dm_timer_init_one(struct omap_dm_timer *timer,
253					 const char *fck_source,
254					 const char *property,
255					 const char **timer_name,
256					 int posted)
257{
258	const char *oh_name = NULL;
259	struct device_node *np;
260	struct omap_hwmod *oh;
261	struct clk *src;
262	int r = 0;
263
264	np = omap_get_timer_dt(omap_timer_match, property);
265	if (!np)
266		return -ENODEV;
267
268	of_property_read_string_index(np, "ti,hwmods", 0, &oh_name);
269	if (!oh_name)
270		return -ENODEV;
271
272	timer->irq = irq_of_parse_and_map(np, 0);
273	if (!timer->irq)
274		return -ENXIO;
275
276	timer->io_base = of_iomap(np, 0);
277
278	timer->fclk = of_clk_get_by_name(np, "fck");
279
280	of_node_put(np);
281
282	oh = omap_hwmod_lookup(oh_name);
283	if (!oh)
284		return -ENODEV;
285
286	*timer_name = oh->name;
 
 
287
 
 
288	if (!timer->io_base)
289		return -ENXIO;
290
291	omap_hwmod_setup_one(oh_name);
292
293	/* After the dmtimer is using hwmod these clocks won't be needed */
294	if (IS_ERR_OR_NULL(timer->fclk))
295		timer->fclk = clk_get(NULL, omap_hwmod_get_main_clk(oh));
296	if (IS_ERR(timer->fclk))
297		return PTR_ERR(timer->fclk);
298
299	src = clk_get(NULL, fck_source);
300	if (IS_ERR(src))
301		return PTR_ERR(src);
 
 
 
302
303	WARN(clk_set_parent(timer->fclk, src) < 0,
304	     "Cannot set timer parent clock, no PLL clock driver?");
305
306	clk_put(src);
307
308	omap_hwmod_enable(oh);
309	__omap_dm_timer_init_regs(timer);
310
311	if (posted)
312		__omap_dm_timer_enable_posted(timer);
 
 
 
 
 
 
 
 
 
 
 
313
314	/* Check that the intended posted configuration matches the actual */
315	if (posted != timer->posted)
316		return -EINVAL;
317
318	timer->rate = clk_get_rate(timer->fclk);
319	timer->reserved = 1;
320
321	return r;
322}
323
324#if !defined(CONFIG_SMP) && defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST)
325void tick_broadcast(const struct cpumask *mask)
326{
327}
328#endif
329
330static void __init omap2_gp_clockevent_init(int gptimer_id,
331						const char *fck_source,
332						const char *property)
333{
334	int res;
335
336	clkev.id = gptimer_id;
337	clkev.errata = omap_dm_timer_get_errata();
338
339	/*
340	 * For clock-event timers we never read the timer counter and
341	 * so we are not impacted by errata i103 and i767. Therefore,
342	 * we can safely ignore this errata for clock-event timers.
343	 */
344	__omap_dm_timer_override_errata(&clkev, OMAP_TIMER_ERRATA_I103_I767);
345
346	res = omap_dm_timer_init_one(&clkev, fck_source, property,
347				     &clockevent_gpt.name, OMAP_TIMER_POSTED);
348	BUG_ON(res);
349
350	omap2_gp_timer_irq.dev_id = &clkev;
351	setup_irq(clkev.irq, &omap2_gp_timer_irq);
352
353	__omap_dm_timer_int_enable(&clkev, OMAP_TIMER_INT_OVERFLOW);
354
355	clockevent_gpt.cpumask = cpu_possible_mask;
356	clockevent_gpt.irq = omap_dm_timer_get_irq(&clkev);
357	clockevents_config_and_register(&clockevent_gpt, clkev.rate,
358					3, /* Timer internal resynch latency */
359					0xffffffff);
360
361	if (soc_is_am33xx() || soc_is_am43xx()) {
362		clockevent_gpt.suspend = omap_clkevt_idle;
363		clockevent_gpt.resume = omap_clkevt_unidle;
364
365		clockevent_gpt_hwmod =
366			omap_hwmod_lookup(clockevent_gpt.name);
367	}
368
369	pr_info("OMAP clockevent source: %s at %lu Hz\n", clockevent_gpt.name,
370		clkev.rate);
371}
372
373/* Clocksource code */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
374static struct omap_dm_timer clksrc;
375static bool use_gptimer_clksrc __initdata;
376
377/*
378 * clocksource
379 */
380static u64 clocksource_read_cycles(struct clocksource *cs)
 
381{
382	return (u64)__omap_dm_timer_read_counter(&clksrc,
383						     OMAP_TIMER_NONPOSTED);
384}
385
386static struct clocksource clocksource_gpt = {
 
387	.rating		= 300,
388	.read		= clocksource_read_cycles,
389	.mask		= CLOCKSOURCE_MASK(32),
390	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
391};
392
393static u64 notrace dmtimer_read_sched_clock(void)
394{
395	if (clksrc.reserved)
396		return __omap_dm_timer_read_counter(&clksrc,
397						    OMAP_TIMER_NONPOSTED);
398
399	return 0;
400}
401
402static const struct of_device_id omap_counter_match[] __initconst = {
403	{ .compatible = "ti,omap-counter32k", },
404	{ }
405};
406
407/* Setup free-running counter for clocksource */
408static int __init __maybe_unused omap2_sync32k_clocksource_init(void)
409{
410	int ret;
411	struct device_node *np = NULL;
412	struct omap_hwmod *oh;
413	const char *oh_name = "counter_32k";
414
415	/*
416	 * See if the 32kHz counter is supported.
417	 */
418	np = omap_get_timer_dt(omap_counter_match, NULL);
419	if (!np)
420		return -ENODEV;
421
422	of_property_read_string_index(np, "ti,hwmods", 0, &oh_name);
423	if (!oh_name)
424		return -ENODEV;
425
426	/*
427	 * First check hwmod data is available for sync32k counter
428	 */
429	oh = omap_hwmod_lookup(oh_name);
430	if (!oh || oh->slaves_cnt == 0)
431		return -ENODEV;
432
433	omap_hwmod_setup_one(oh_name);
434
435	ret = omap_hwmod_enable(oh);
436	if (ret) {
437		pr_warn("%s: failed to enable counter_32k module (%d)\n",
438							__func__, ret);
439		return ret;
440	}
441
442	return ret;
443}
444
445static void __init omap2_gptimer_clocksource_init(int gptimer_id,
446						  const char *fck_source,
447						  const char *property)
448{
449	int res;
450
451	clksrc.id = gptimer_id;
452	clksrc.errata = omap_dm_timer_get_errata();
453
454	res = omap_dm_timer_init_one(&clksrc, fck_source, property,
455				     &clocksource_gpt.name,
456				     OMAP_TIMER_NONPOSTED);
457	BUG_ON(res);
458
459	__omap_dm_timer_load_start(&clksrc,
460				   OMAP_TIMER_CTRL_ST | OMAP_TIMER_CTRL_AR, 0,
461				   OMAP_TIMER_NONPOSTED);
462	sched_clock_register(dmtimer_read_sched_clock, 32, clksrc.rate);
463
464	if (clocksource_register_hz(&clocksource_gpt, clksrc.rate))
465		pr_err("Could not register clocksource %s\n",
466			clocksource_gpt.name);
467	else
468		pr_info("OMAP clocksource: %s at %lu Hz\n",
469			clocksource_gpt.name, clksrc.rate);
470}
 
471
472static void __init __omap_sync32k_timer_init(int clkev_nr, const char *clkev_src,
473		const char *clkev_prop, int clksrc_nr, const char *clksrc_src,
474		const char *clksrc_prop, bool gptimer)
475{
476	omap_clk_init();
477	omap_dmtimer_init();
478	omap2_gp_clockevent_init(clkev_nr, clkev_src, clkev_prop);
479
480	/* Enable the use of clocksource="gp_timer" kernel parameter */
481	if (use_gptimer_clksrc || gptimer)
482		omap2_gptimer_clocksource_init(clksrc_nr, clksrc_src,
483						clksrc_prop);
484	else
485		omap2_sync32k_clocksource_init();
486}
487
488void __init omap_init_time(void)
489{
490	__omap_sync32k_timer_init(1, "timer_32k_ck", "ti,timer-alwon",
491			2, "timer_sys_ck", NULL, false);
492
493	timer_probe();
494}
495
496#if defined(CONFIG_ARCH_OMAP3) || defined(CONFIG_SOC_AM43XX)
497void __init omap3_secure_sync32k_timer_init(void)
498{
499	__omap_sync32k_timer_init(12, "secure_32k_fck", "ti,timer-secure",
500			2, "timer_sys_ck", NULL, false);
501
502	timer_probe();
503}
504#endif /* CONFIG_ARCH_OMAP3 */
505
506#if defined(CONFIG_ARCH_OMAP3) || defined(CONFIG_SOC_AM33XX) || \
507	defined(CONFIG_SOC_AM43XX)
508void __init omap3_gptimer_timer_init(void)
509{
510	__omap_sync32k_timer_init(2, "timer_sys_ck", NULL,
511			1, "timer_sys_ck", "ti,timer-alwon", true);
512	if (of_have_populated_dt())
513		timer_probe();
514}
515#endif
516
517#if defined(CONFIG_ARCH_OMAP4) || defined(CONFIG_SOC_OMAP5) ||		\
518	defined(CONFIG_SOC_DRA7XX)
519static void __init omap4_sync32k_timer_init(void)
520{
521	__omap_sync32k_timer_init(1, "timer_32k_ck", "ti,timer-alwon",
522			2, "sys_clkin_ck", NULL, false);
523}
524
525void __init omap4_local_timer_init(void)
526{
527	omap4_sync32k_timer_init();
528	timer_probe();
529}
530#endif
531
532#if defined(CONFIG_SOC_OMAP5) || defined(CONFIG_SOC_DRA7XX)
533
534/*
535 * The realtime counter also called master counter, is a free-running
536 * counter, which is related to real time. It produces the count used
537 * by the CPU local timer peripherals in the MPU cluster. The timer counts
538 * at a rate of 6.144 MHz. Because the device operates on different clocks
539 * in different power modes, the master counter shifts operation between
540 * clocks, adjusting the increment per clock in hardware accordingly to
541 * maintain a constant count rate.
542 */
543static void __init realtime_counter_init(void)
544{
545#ifdef CONFIG_SOC_HAS_REALTIME_COUNTER
546	void __iomem *base;
547	static struct clk *sys_clk;
548	unsigned long rate;
549	unsigned int reg;
550	unsigned long long num, den;
551
552	base = ioremap(REALTIME_COUNTER_BASE, SZ_32);
553	if (!base) {
554		pr_err("%s: ioremap failed\n", __func__);
555		return;
556	}
557	sys_clk = clk_get(NULL, "sys_clkin");
558	if (IS_ERR(sys_clk)) {
559		pr_err("%s: failed to get system clock handle\n", __func__);
560		iounmap(base);
561		return;
562	}
563
564	rate = clk_get_rate(sys_clk);
565
566	if (soc_is_dra7xx()) {
567		/*
568		 * Errata i856 says the 32.768KHz crystal does not start at
569		 * power on, so the CPU falls back to an emulated 32KHz clock
570		 * based on sysclk / 610 instead. This causes the master counter
571		 * frequency to not be 6.144MHz but at sysclk / 610 * 375 / 2
572		 * (OR sysclk * 75 / 244)
573		 *
574		 * This affects at least the DRA7/AM572x 1.0, 1.1 revisions.
575		 * Of course any board built without a populated 32.768KHz
576		 * crystal would also need this fix even if the CPU is fixed
577		 * later.
578		 *
579		 * Either case can be detected by using the two speedselect bits
580		 * If they are not 0, then the 32.768KHz clock driving the
581		 * coarse counter that corrects the fine counter every time it
582		 * ticks is actually rate/610 rather than 32.768KHz and we
583		 * should compensate to avoid the 570ppm (at 20MHz, much worse
584		 * at other rates) too fast system time.
585		 */
586		reg = omap_ctrl_readl(DRA7_CTRL_CORE_BOOTSTRAP);
587		if (reg & DRA7_SPEEDSELECT_MASK) {
588			num = 75;
589			den = 244;
590			goto sysclk1_based;
591		}
592	}
593
594	/* Numerator/denumerator values refer TRM Realtime Counter section */
595	switch (rate) {
596	case 12000000:
597		num = 64;
598		den = 125;
599		break;
600	case 13000000:
601		num = 768;
602		den = 1625;
603		break;
604	case 19200000:
605		num = 8;
606		den = 25;
607		break;
608	case 20000000:
609		num = 192;
610		den = 625;
611		break;
612	case 26000000:
613		num = 384;
614		den = 1625;
615		break;
616	case 27000000:
617		num = 256;
618		den = 1125;
619		break;
620	case 38400000:
621	default:
622		/* Program it for 38.4 MHz */
623		num = 4;
624		den = 25;
625		break;
626	}
627
628sysclk1_based:
629	/* Program numerator and denumerator registers */
630	reg = readl_relaxed(base + INCREMENTER_NUMERATOR_OFFSET) &
631			NUMERATOR_DENUMERATOR_MASK;
632	reg |= num;
633	writel_relaxed(reg, base + INCREMENTER_NUMERATOR_OFFSET);
634
635	reg = readl_relaxed(base + INCREMENTER_DENUMERATOR_RELOAD_OFFSET) &
636			NUMERATOR_DENUMERATOR_MASK;
637	reg |= den;
638	writel_relaxed(reg, base + INCREMENTER_DENUMERATOR_RELOAD_OFFSET);
639
640	arch_timer_freq = DIV_ROUND_UP_ULL(rate * num, den);
641	set_cntfreq();
642
643	iounmap(base);
644#endif
 
 
645}
646
647void __init omap5_realtime_timer_init(void)
648{
649	omap4_sync32k_timer_init();
650	realtime_counter_init();
651
652	timer_probe();
653}
654#endif /* CONFIG_SOC_OMAP5 || CONFIG_SOC_DRA7XX */
655
656/**
657 * omap2_override_clocksource - clocksource override with user configuration
658 *
659 * Allows user to override default clocksource, using kernel parameter
660 *   clocksource="gp_timer"	(For all OMAP2PLUS architectures)
661 *
662 * Note that, here we are using same standard kernel parameter "clocksource=",
663 * and not introducing any OMAP specific interface.
664 */
665static int __init omap2_override_clocksource(char *str)
666{
667	if (!str)
668		return 0;
669	/*
670	 * For OMAP architecture, we only have two options
671	 *    - sync_32k (default)
672	 *    - gp_timer (sys_clk based)
673	 */
674	if (!strcmp(str, "gp_timer"))
675		use_gptimer_clksrc = true;
676
677	return 0;
678}
679early_param("clocksource", omap2_override_clocksource);