mirror of https://gitee.com/openkylin/linux.git
301 lines
6.9 KiB
C
301 lines
6.9 KiB
C
/*
|
|
* linux/arch/arm/common/timer-sp.c
|
|
*
|
|
* Copyright (C) 1999 - 2003 ARM Limited
|
|
* Copyright (C) 2000 Deep Blue Solutions Ltd
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
|
*/
|
|
#include <linux/clk.h>
|
|
#include <linux/clocksource.h>
|
|
#include <linux/clockchips.h>
|
|
#include <linux/err.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/irq.h>
|
|
#include <linux/io.h>
|
|
#include <linux/of.h>
|
|
#include <linux/of_address.h>
|
|
#include <linux/of_irq.h>
|
|
#include <linux/sched_clock.h>
|
|
|
|
#include <asm/hardware/arm_timer.h>
|
|
#include <asm/hardware/timer-sp.h>
|
|
|
|
static long __init sp804_get_clock_rate(struct clk *clk)
|
|
{
|
|
long rate;
|
|
int err;
|
|
|
|
err = clk_prepare(clk);
|
|
if (err) {
|
|
pr_err("sp804: clock failed to prepare: %d\n", err);
|
|
clk_put(clk);
|
|
return err;
|
|
}
|
|
|
|
err = clk_enable(clk);
|
|
if (err) {
|
|
pr_err("sp804: clock failed to enable: %d\n", err);
|
|
clk_unprepare(clk);
|
|
clk_put(clk);
|
|
return err;
|
|
}
|
|
|
|
rate = clk_get_rate(clk);
|
|
if (rate < 0) {
|
|
pr_err("sp804: clock failed to get rate: %ld\n", rate);
|
|
clk_disable(clk);
|
|
clk_unprepare(clk);
|
|
clk_put(clk);
|
|
}
|
|
|
|
return rate;
|
|
}
|
|
|
|
static void __iomem *sched_clock_base;
|
|
|
|
static u32 sp804_read(void)
|
|
{
|
|
return ~readl_relaxed(sched_clock_base + TIMER_VALUE);
|
|
}
|
|
|
|
void __init __sp804_clocksource_and_sched_clock_init(void __iomem *base,
|
|
const char *name,
|
|
struct clk *clk,
|
|
int use_sched_clock)
|
|
{
|
|
long rate;
|
|
|
|
if (!clk) {
|
|
clk = clk_get_sys("sp804", name);
|
|
if (IS_ERR(clk)) {
|
|
pr_err("sp804: clock not found: %d\n",
|
|
(int)PTR_ERR(clk));
|
|
return;
|
|
}
|
|
}
|
|
|
|
rate = sp804_get_clock_rate(clk);
|
|
|
|
if (rate < 0)
|
|
return;
|
|
|
|
/* setup timer 0 as free-running clocksource */
|
|
writel(0, base + TIMER_CTRL);
|
|
writel(0xffffffff, base + TIMER_LOAD);
|
|
writel(0xffffffff, base + TIMER_VALUE);
|
|
writel(TIMER_CTRL_32BIT | TIMER_CTRL_ENABLE | TIMER_CTRL_PERIODIC,
|
|
base + TIMER_CTRL);
|
|
|
|
clocksource_mmio_init(base + TIMER_VALUE, name,
|
|
rate, 200, 32, clocksource_mmio_readl_down);
|
|
|
|
if (use_sched_clock) {
|
|
sched_clock_base = base;
|
|
setup_sched_clock(sp804_read, 32, rate);
|
|
}
|
|
}
|
|
|
|
|
|
static void __iomem *clkevt_base;
|
|
static unsigned long clkevt_reload;
|
|
|
|
/*
|
|
* IRQ handler for the timer
|
|
*/
|
|
static irqreturn_t sp804_timer_interrupt(int irq, void *dev_id)
|
|
{
|
|
struct clock_event_device *evt = dev_id;
|
|
|
|
/* clear the interrupt */
|
|
writel(1, clkevt_base + TIMER_INTCLR);
|
|
|
|
evt->event_handler(evt);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static void sp804_set_mode(enum clock_event_mode mode,
|
|
struct clock_event_device *evt)
|
|
{
|
|
unsigned long ctrl = TIMER_CTRL_32BIT | TIMER_CTRL_IE;
|
|
|
|
writel(ctrl, clkevt_base + TIMER_CTRL);
|
|
|
|
switch (mode) {
|
|
case CLOCK_EVT_MODE_PERIODIC:
|
|
writel(clkevt_reload, clkevt_base + TIMER_LOAD);
|
|
ctrl |= TIMER_CTRL_PERIODIC | TIMER_CTRL_ENABLE;
|
|
break;
|
|
|
|
case CLOCK_EVT_MODE_ONESHOT:
|
|
/* period set, and timer enabled in 'next_event' hook */
|
|
ctrl |= TIMER_CTRL_ONESHOT;
|
|
break;
|
|
|
|
case CLOCK_EVT_MODE_UNUSED:
|
|
case CLOCK_EVT_MODE_SHUTDOWN:
|
|
default:
|
|
break;
|
|
}
|
|
|
|
writel(ctrl, clkevt_base + TIMER_CTRL);
|
|
}
|
|
|
|
static int sp804_set_next_event(unsigned long next,
|
|
struct clock_event_device *evt)
|
|
{
|
|
unsigned long ctrl = readl(clkevt_base + TIMER_CTRL);
|
|
|
|
writel(next, clkevt_base + TIMER_LOAD);
|
|
writel(ctrl | TIMER_CTRL_ENABLE, clkevt_base + TIMER_CTRL);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct clock_event_device sp804_clockevent = {
|
|
.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT |
|
|
CLOCK_EVT_FEAT_DYNIRQ,
|
|
.set_mode = sp804_set_mode,
|
|
.set_next_event = sp804_set_next_event,
|
|
.rating = 300,
|
|
};
|
|
|
|
static struct irqaction sp804_timer_irq = {
|
|
.name = "timer",
|
|
.flags = IRQF_TIMER | IRQF_IRQPOLL,
|
|
.handler = sp804_timer_interrupt,
|
|
.dev_id = &sp804_clockevent,
|
|
};
|
|
|
|
void __init __sp804_clockevents_init(void __iomem *base, unsigned int irq, struct clk *clk, const char *name)
|
|
{
|
|
struct clock_event_device *evt = &sp804_clockevent;
|
|
long rate;
|
|
|
|
if (!clk)
|
|
clk = clk_get_sys("sp804", name);
|
|
if (IS_ERR(clk)) {
|
|
pr_err("sp804: %s clock not found: %d\n", name,
|
|
(int)PTR_ERR(clk));
|
|
return;
|
|
}
|
|
|
|
rate = sp804_get_clock_rate(clk);
|
|
if (rate < 0)
|
|
return;
|
|
|
|
clkevt_base = base;
|
|
clkevt_reload = DIV_ROUND_CLOSEST(rate, HZ);
|
|
evt->name = name;
|
|
evt->irq = irq;
|
|
evt->cpumask = cpu_possible_mask;
|
|
|
|
writel(0, base + TIMER_CTRL);
|
|
|
|
setup_irq(irq, &sp804_timer_irq);
|
|
clockevents_config_and_register(evt, rate, 0xf, 0xffffffff);
|
|
}
|
|
|
|
static void __init sp804_of_init(struct device_node *np)
|
|
{
|
|
static bool initialized = false;
|
|
void __iomem *base;
|
|
int irq;
|
|
u32 irq_num = 0;
|
|
struct clk *clk1, *clk2;
|
|
const char *name = of_get_property(np, "compatible", NULL);
|
|
|
|
base = of_iomap(np, 0);
|
|
if (WARN_ON(!base))
|
|
return;
|
|
|
|
/* Ensure timers are disabled */
|
|
writel(0, base + TIMER_CTRL);
|
|
writel(0, base + TIMER_2_BASE + TIMER_CTRL);
|
|
|
|
if (initialized || !of_device_is_available(np))
|
|
goto err;
|
|
|
|
clk1 = of_clk_get(np, 0);
|
|
if (IS_ERR(clk1))
|
|
clk1 = NULL;
|
|
|
|
/* Get the 2nd clock if the timer has 2 timer clocks */
|
|
if (of_count_phandle_with_args(np, "clocks", "#clock-cells") == 3) {
|
|
clk2 = of_clk_get(np, 1);
|
|
if (IS_ERR(clk2)) {
|
|
pr_err("sp804: %s clock not found: %d\n", np->name,
|
|
(int)PTR_ERR(clk2));
|
|
goto err;
|
|
}
|
|
} else
|
|
clk2 = clk1;
|
|
|
|
irq = irq_of_parse_and_map(np, 0);
|
|
if (irq <= 0)
|
|
goto err;
|
|
|
|
of_property_read_u32(np, "arm,sp804-has-irq", &irq_num);
|
|
if (irq_num == 2) {
|
|
__sp804_clockevents_init(base + TIMER_2_BASE, irq, clk2, name);
|
|
__sp804_clocksource_and_sched_clock_init(base, name, clk1, 1);
|
|
} else {
|
|
__sp804_clockevents_init(base, irq, clk1 , name);
|
|
__sp804_clocksource_and_sched_clock_init(base + TIMER_2_BASE,
|
|
name, clk2, 1);
|
|
}
|
|
initialized = true;
|
|
|
|
return;
|
|
err:
|
|
iounmap(base);
|
|
}
|
|
CLOCKSOURCE_OF_DECLARE(sp804, "arm,sp804", sp804_of_init);
|
|
|
|
static void __init integrator_cp_of_init(struct device_node *np)
|
|
{
|
|
static int init_count = 0;
|
|
void __iomem *base;
|
|
int irq;
|
|
const char *name = of_get_property(np, "compatible", NULL);
|
|
|
|
base = of_iomap(np, 0);
|
|
if (WARN_ON(!base))
|
|
return;
|
|
|
|
/* Ensure timer is disabled */
|
|
writel(0, base + TIMER_CTRL);
|
|
|
|
if (init_count == 2 || !of_device_is_available(np))
|
|
goto err;
|
|
|
|
if (!init_count)
|
|
sp804_clocksource_init(base, name);
|
|
else {
|
|
irq = irq_of_parse_and_map(np, 0);
|
|
if (irq <= 0)
|
|
goto err;
|
|
|
|
sp804_clockevents_init(base, irq, name);
|
|
}
|
|
|
|
init_count++;
|
|
return;
|
|
err:
|
|
iounmap(base);
|
|
}
|
|
CLOCKSOURCE_OF_DECLARE(intcp, "arm,integrator-cp-timer", integrator_cp_of_init);
|