/*
* Copyright (c) 2011 Picochip Ltd., Jamie Iles
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* All enquiries to support@picochip.com
*/
#include <linux/dw_apb_timer.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_irq.h>
#include <linux/sched.h>
#include <asm/mach/time.h>
#include <asm/sched_clock.h>
#include "common.h"
static void timer_get_base_and_rate(struct device_node *np,
void __iomem **base, u32 *rate)
{
*base = of_iomap(np, 0);
if (!*base)
panic("Unable to map regs for %s", np->name);
if (of_property_read_u32(np, "clock-freq", rate))
panic("No clock-freq property for %s", np->name);
}
static void picoxcell_add_clockevent(struct device_node *event_timer)
{
void __iomem *iobase;
struct dw_apb_clock_event_device *ced;
u32 irq, rate;
irq = irq_of_parse_and_map(event_timer, 0);
if (irq == NO_IRQ)
panic("No IRQ for clock event timer");
timer_get_base_and_rate(event_timer, &iobase, &rate);
ced = dw_apb_clockevent_init(0, event_timer->name, 300, iobase, irq,
rate);
if (!ced)
panic("Unable to initialise clockevent device");
dw_apb_clockevent_register(ced);
}
static void picoxcell_add_clocksource(struct device_node *source_timer)
{
void __iomem *iobase;
struct dw_apb_clocksource *cs;
u32 rate;
timer_get_base_and_rate(source_timer, &iobase, &rate);
cs = dw_apb_clocksource_init(300, source_timer->name, iobase, rate);
if (!cs)
panic("Unable to initialise clocksource device");
dw_apb_clocksource_start(cs);
dw_apb_clocksource_register(cs);
}
static DEFINE_CLOCK_DATA(cd);
static void __iomem *sched_io_base;
unsigned long long notrace sched_clock(void)
{
cycle_t cyc = sched_io_base ? __raw_readl(sched_io_base) : 0;
return cyc_to_sched_clock(&cd, cyc, (u32)~0);
}
static void notrace picoxcell_update_sched_clock(void)
{
cycle_t cyc = sched_io_base ? __raw_readl(sched_io_base) : 0;
update_sched_clock(&cd, cyc, (u32)~0);
}
static const struct of_device_id picoxcell_rtc_ids[] __initconst = {
{ .compatible = "picochip,pc3x2-rtc" },
{ /* Sentinel */ },
};
static void picoxcell_init_sched_clock(void)
{
struct device_node *sched_timer;
u32 rate;
sched_timer = of_find_matching_node(NULL, picoxcell_rtc_ids);
if (!sched_timer)
panic("No RTC for sched clock to use");
timer_get_base_and_rate(sched_timer, &sched_io_base, &rate);
of_node_put(sched_timer);
init_sched_clock(&cd, picoxcell_update_sched_clock, 32, rate);
}
static const struct of_device_id picoxcell_timer_ids[] __initconst = {
{ .compatible = "picochip,pc3x2-timer" },
{},
};
static void __init picoxcell_timer_init(void)
{
struct device_node *event_timer, *source_timer;
event_timer = of_find_matching_node(NULL, picoxcell_timer_ids);
if (!event_timer)
panic("No timer for clockevent");
picoxcell_add_clockevent(event_timer);
source_timer = of_find_matching_node(event_timer, picoxcell_timer_ids);
if (!source_timer)
panic("No timer for clocksource");
picoxcell_add_clocksource(source_timer);
of_node_put(source_timer);
picoxcell_init_sched_clock();
}
struct sys_timer picoxcell_timer = {
.init = picoxcell_timer_init,
};
