linux/drivers/clocksource/timer-sp804.c
Thomas Gleixner 1a59d1b8e0 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156
Based on 1 normalized pattern(s):

  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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:35 -07:00

327 lines
6.9 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* linux/drivers/clocksource/timer-sp.c
*
* Copyright (C) 1999 - 2003 ARM Limited
* Copyright (C) 2000 Deep Blue Solutions Ltd
*/
#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_clk.h>
#include <linux/of_irq.h>
#include <linux/sched_clock.h>
#include <clocksource/timer-sp804.h>
#include "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 u64 notrace sp804_read(void)
{
return ~readl_relaxed(sched_clock_base + TIMER_VALUE);
}
void __init sp804_timer_disable(void __iomem *base)
{
writel(0, base + TIMER_CTRL);
}
int __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 PTR_ERR(clk);
}
}
rate = sp804_get_clock_rate(clk);
if (rate < 0)
return -EINVAL;
/* 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;
sched_clock_register(sp804_read, 32, rate);
}
return 0;
}
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 inline void timer_shutdown(struct clock_event_device *evt)
{
writel(0, clkevt_base + TIMER_CTRL);
}
static int sp804_shutdown(struct clock_event_device *evt)
{
timer_shutdown(evt);
return 0;
}
static int sp804_set_periodic(struct clock_event_device *evt)
{
unsigned long ctrl = TIMER_CTRL_32BIT | TIMER_CTRL_IE |
TIMER_CTRL_PERIODIC | TIMER_CTRL_ENABLE;
timer_shutdown(evt);
writel(clkevt_reload, clkevt_base + TIMER_LOAD);
writel(ctrl, clkevt_base + TIMER_CTRL);
return 0;
}
static int sp804_set_next_event(unsigned long next,
struct clock_event_device *evt)
{
unsigned long ctrl = TIMER_CTRL_32BIT | TIMER_CTRL_IE |
TIMER_CTRL_ONESHOT | TIMER_CTRL_ENABLE;
writel(next, clkevt_base + TIMER_LOAD);
writel(ctrl, 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_state_shutdown = sp804_shutdown,
.set_state_periodic = sp804_set_periodic,
.set_state_oneshot = sp804_shutdown,
.tick_resume = sp804_shutdown,
.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,
};
int __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 PTR_ERR(clk);
}
rate = sp804_get_clock_rate(clk);
if (rate < 0)
return -EINVAL;
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);
return 0;
}
static int __init sp804_of_init(struct device_node *np)
{
static bool initialized = false;
void __iomem *base;
int irq, ret = -EINVAL;
u32 irq_num = 0;
struct clk *clk1, *clk2;
const char *name = of_get_property(np, "compatible", NULL);
base = of_iomap(np, 0);
if (!base)
return -ENXIO;
/* Ensure timers are disabled */
writel(0, base + TIMER_CTRL);
writel(0, base + TIMER_2_BASE + TIMER_CTRL);
if (initialized || !of_device_is_available(np)) {
ret = -EINVAL;
goto err;
}
clk1 = of_clk_get(np, 0);
if (IS_ERR(clk1))
clk1 = NULL;
/* Get the 2nd clock if the timer has 3 timer clocks */
if (of_clk_get_parent_count(np) == 3) {
clk2 = of_clk_get(np, 1);
if (IS_ERR(clk2)) {
pr_err("sp804: %pOFn clock not found: %d\n", np,
(int)PTR_ERR(clk2));
clk2 = NULL;
}
} 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) {
ret = __sp804_clockevents_init(base + TIMER_2_BASE, irq, clk2, name);
if (ret)
goto err;
ret = __sp804_clocksource_and_sched_clock_init(base, name, clk1, 1);
if (ret)
goto err;
} else {
ret = __sp804_clockevents_init(base, irq, clk1 , name);
if (ret)
goto err;
ret =__sp804_clocksource_and_sched_clock_init(base + TIMER_2_BASE,
name, clk2, 1);
if (ret)
goto err;
}
initialized = true;
return 0;
err:
iounmap(base);
return ret;
}
TIMER_OF_DECLARE(sp804, "arm,sp804", sp804_of_init);
static int __init integrator_cp_of_init(struct device_node *np)
{
static int init_count = 0;
void __iomem *base;
int irq, ret = -EINVAL;
const char *name = of_get_property(np, "compatible", NULL);
struct clk *clk;
base = of_iomap(np, 0);
if (!base) {
pr_err("Failed to iomap\n");
return -ENXIO;
}
clk = of_clk_get(np, 0);
if (IS_ERR(clk)) {
pr_err("Failed to get clock\n");
return PTR_ERR(clk);
}
/* Ensure timer is disabled */
writel(0, base + TIMER_CTRL);
if (init_count == 2 || !of_device_is_available(np))
goto err;
if (!init_count) {
ret = __sp804_clocksource_and_sched_clock_init(base, name, clk, 0);
if (ret)
goto err;
} else {
irq = irq_of_parse_and_map(np, 0);
if (irq <= 0)
goto err;
ret = __sp804_clockevents_init(base, irq, clk, name);
if (ret)
goto err;
}
init_count++;
return 0;
err:
iounmap(base);
return ret;
}
TIMER_OF_DECLARE(intcp, "arm,integrator-cp-timer", integrator_cp_of_init);