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- /*
- * linux/arch/arm/mach-omap2/timer.c
- *
- * OMAP2 GP timer support.
- *
- * Copyright (C) 2009 Nokia Corporation
- *
- * Update to use new clocksource/clockevent layers
- * Author: Kevin Hilman, MontaVista Software, Inc. <source@mvista.com>
- * Copyright (C) 2007 MontaVista Software, Inc.
- *
- * Original driver:
- * Copyright (C) 2005 Nokia Corporation
- * Author: Paul Mundt <paul.mundt@nokia.com>
- * Juha Yrjölä <juha.yrjola@nokia.com>
- * OMAP Dual-mode timer framework support by Timo Teras
- *
- * Some parts based off of TI's 24xx code:
- *
- * Copyright (C) 2004-2009 Texas Instruments, Inc.
- *
- * Roughly modelled after the OMAP1 MPU timer code.
- * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
- *
- * This file is subject to the terms and conditions of the GNU General Public
- * License. See the file "COPYING" in the main directory of this archive
- * for more details.
- */
- #include <linux/init.h>
- #include <linux/time.h>
- #include <linux/interrupt.h>
- #include <linux/err.h>
- #include <linux/clk.h>
- #include <linux/delay.h>
- #include <linux/irq.h>
- #include <linux/clocksource.h>
- #include <linux/clockchips.h>
- #include <linux/slab.h>
- #include <linux/of.h>
- #include <linux/of_address.h>
- #include <linux/of_irq.h>
- #include <linux/platform_device.h>
- #include <linux/platform_data/dmtimer-omap.h>
- #include <asm/mach/time.h>
- #include <asm/smp_twd.h>
- #include <asm/sched_clock.h>
- #include <asm/arch_timer.h>
- #include "omap_hwmod.h"
- #include "omap_device.h"
- #include <plat/counter-32k.h>
- #include <plat/dmtimer.h>
- #include "omap-pm.h"
- #include "soc.h"
- #include "common.h"
- #include "powerdomain.h"
- /* Parent clocks, eventually these will come from the clock framework */
- #define OMAP2_MPU_SOURCE "sys_ck"
- #define OMAP3_MPU_SOURCE OMAP2_MPU_SOURCE
- #define OMAP4_MPU_SOURCE "sys_clkin_ck"
- #define OMAP2_32K_SOURCE "func_32k_ck"
- #define OMAP3_32K_SOURCE "omap_32k_fck"
- #define OMAP4_32K_SOURCE "sys_32k_ck"
- #define REALTIME_COUNTER_BASE 0x48243200
- #define INCREMENTER_NUMERATOR_OFFSET 0x10
- #define INCREMENTER_DENUMERATOR_RELOAD_OFFSET 0x14
- #define NUMERATOR_DENUMERATOR_MASK 0xfffff000
- /* Clockevent code */
- static struct omap_dm_timer clkev;
- static struct clock_event_device clockevent_gpt;
- static irqreturn_t omap2_gp_timer_interrupt(int irq, void *dev_id)
- {
- struct clock_event_device *evt = &clockevent_gpt;
- __omap_dm_timer_write_status(&clkev, OMAP_TIMER_INT_OVERFLOW);
- evt->event_handler(evt);
- return IRQ_HANDLED;
- }
- static struct irqaction omap2_gp_timer_irq = {
- .name = "gp_timer",
- .flags = IRQF_DISABLED | IRQF_TIMER | IRQF_IRQPOLL,
- .handler = omap2_gp_timer_interrupt,
- };
- static int omap2_gp_timer_set_next_event(unsigned long cycles,
- struct clock_event_device *evt)
- {
- __omap_dm_timer_load_start(&clkev, OMAP_TIMER_CTRL_ST,
- 0xffffffff - cycles, OMAP_TIMER_POSTED);
- return 0;
- }
- static void omap2_gp_timer_set_mode(enum clock_event_mode mode,
- struct clock_event_device *evt)
- {
- u32 period;
- __omap_dm_timer_stop(&clkev, OMAP_TIMER_POSTED, clkev.rate);
- switch (mode) {
- case CLOCK_EVT_MODE_PERIODIC:
- period = clkev.rate / HZ;
- period -= 1;
- /* Looks like we need to first set the load value separately */
- __omap_dm_timer_write(&clkev, OMAP_TIMER_LOAD_REG,
- 0xffffffff - period, OMAP_TIMER_POSTED);
- __omap_dm_timer_load_start(&clkev,
- OMAP_TIMER_CTRL_AR | OMAP_TIMER_CTRL_ST,
- 0xffffffff - period, OMAP_TIMER_POSTED);
- break;
- case CLOCK_EVT_MODE_ONESHOT:
- break;
- case CLOCK_EVT_MODE_UNUSED:
- case CLOCK_EVT_MODE_SHUTDOWN:
- case CLOCK_EVT_MODE_RESUME:
- break;
- }
- }
- static struct clock_event_device clockevent_gpt = {
- .name = "gp_timer",
- .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
- .shift = 32,
- .rating = 300,
- .set_next_event = omap2_gp_timer_set_next_event,
- .set_mode = omap2_gp_timer_set_mode,
- };
- static struct property device_disabled = {
- .name = "status",
- .length = sizeof("disabled"),
- .value = "disabled",
- };
- static struct of_device_id omap_timer_match[] __initdata = {
- { .compatible = "ti,omap2-timer", },
- { }
- };
- /**
- * omap_get_timer_dt - get a timer using device-tree
- * @match - device-tree match structure for matching a device type
- * @property - optional timer property to match
- *
- * Helper function to get a timer during early boot using device-tree for use
- * as kernel system timer. Optionally, the property argument can be used to
- * select a timer with a specific property. Once a timer is found then mark
- * the timer node in device-tree as disabled, to prevent the kernel from
- * registering this timer as a platform device and so no one else can use it.
- */
- static struct device_node * __init omap_get_timer_dt(struct of_device_id *match,
- const char *property)
- {
- struct device_node *np;
- for_each_matching_node(np, match) {
- if (!of_device_is_available(np))
- continue;
- if (property && !of_get_property(np, property, NULL))
- continue;
- of_add_property(np, &device_disabled);
- return np;
- }
- return NULL;
- }
- /**
- * omap_dmtimer_init - initialisation function when device tree is used
- *
- * For secure OMAP3 devices, timers with device type "timer-secure" cannot
- * be used by the kernel as they are reserved. Therefore, to prevent the
- * kernel registering these devices remove them dynamically from the device
- * tree on boot.
- */
- static void __init omap_dmtimer_init(void)
- {
- struct device_node *np;
- if (!cpu_is_omap34xx())
- return;
- /* If we are a secure device, remove any secure timer nodes */
- if ((omap_type() != OMAP2_DEVICE_TYPE_GP)) {
- np = omap_get_timer_dt(omap_timer_match, "ti,timer-secure");
- if (np)
- of_node_put(np);
- }
- }
- /**
- * omap_dm_timer_get_errata - get errata flags for a timer
- *
- * Get the timer errata flags that are specific to the OMAP device being used.
- */
- static u32 __init omap_dm_timer_get_errata(void)
- {
- if (cpu_is_omap24xx())
- return 0;
- return OMAP_TIMER_ERRATA_I103_I767;
- }
- static int __init omap_dm_timer_init_one(struct omap_dm_timer *timer,
- int gptimer_id,
- const char *fck_source,
- const char *property,
- int posted)
- {
- char name[10]; /* 10 = sizeof("gptXX_Xck0") */
- const char *oh_name;
- struct device_node *np;
- struct omap_hwmod *oh;
- struct resource irq, mem;
- int r = 0;
- if (of_have_populated_dt()) {
- np = omap_get_timer_dt(omap_timer_match, NULL);
- if (!np)
- return -ENODEV;
- of_property_read_string_index(np, "ti,hwmods", 0, &oh_name);
- if (!oh_name)
- return -ENODEV;
- timer->irq = irq_of_parse_and_map(np, 0);
- if (!timer->irq)
- return -ENXIO;
- timer->io_base = of_iomap(np, 0);
- of_node_put(np);
- } else {
- if (omap_dm_timer_reserve_systimer(gptimer_id))
- return -ENODEV;
- sprintf(name, "timer%d", gptimer_id);
- oh_name = name;
- }
- oh = omap_hwmod_lookup(oh_name);
- if (!oh)
- return -ENODEV;
- if (!of_have_populated_dt()) {
- r = omap_hwmod_get_resource_byname(oh, IORESOURCE_IRQ, NULL,
- &irq);
- if (r)
- return -ENXIO;
- timer->irq = irq.start;
- r = omap_hwmod_get_resource_byname(oh, IORESOURCE_MEM, NULL,
- &mem);
- if (r)
- return -ENXIO;
- /* Static mapping, never released */
- timer->io_base = ioremap(mem.start, mem.end - mem.start);
- }
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