mirror of https://gitee.com/openkylin/linux.git
254 lines
5.4 KiB
C
254 lines
5.4 KiB
C
/*
|
|
* H8/300 16bit Timer driver
|
|
*
|
|
* Copyright 2015 Yoshinori Sato <ysato@users.sourcefoge.jp>
|
|
*/
|
|
|
|
#include <linux/errno.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/param.h>
|
|
#include <linux/string.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/init.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/clocksource.h>
|
|
#include <linux/module.h>
|
|
#include <linux/clk.h>
|
|
#include <linux/io.h>
|
|
#include <linux/of.h>
|
|
|
|
#include <asm/segment.h>
|
|
#include <asm/irq.h>
|
|
|
|
#define TSTR 0
|
|
#define TSNC 1
|
|
#define TMDR 2
|
|
#define TOLR 3
|
|
#define TISRA 4
|
|
#define TISRB 5
|
|
#define TISRC 6
|
|
|
|
#define TCR 0
|
|
#define TIOR 1
|
|
#define TCNT 2
|
|
#define GRA 4
|
|
#define GRB 6
|
|
|
|
#define FLAG_REPROGRAM (1 << 0)
|
|
#define FLAG_SKIPEVENT (1 << 1)
|
|
#define FLAG_IRQCONTEXT (1 << 2)
|
|
#define FLAG_STARTED (1 << 3)
|
|
|
|
#define ONESHOT 0
|
|
#define PERIODIC 1
|
|
|
|
#define RELATIVE 0
|
|
#define ABSOLUTE 1
|
|
|
|
struct timer16_priv {
|
|
struct platform_device *pdev;
|
|
struct clocksource cs;
|
|
struct irqaction irqaction;
|
|
unsigned long total_cycles;
|
|
unsigned long mapbase;
|
|
unsigned long mapcommon;
|
|
unsigned long flags;
|
|
unsigned short gra;
|
|
unsigned short cs_enabled;
|
|
unsigned char enb;
|
|
unsigned char imfa;
|
|
unsigned char imiea;
|
|
unsigned char ovf;
|
|
raw_spinlock_t lock;
|
|
struct clk *clk;
|
|
};
|
|
|
|
static unsigned long timer16_get_counter(struct timer16_priv *p)
|
|
{
|
|
unsigned long v1, v2, v3;
|
|
int o1, o2;
|
|
|
|
o1 = ctrl_inb(p->mapcommon + TISRC) & p->ovf;
|
|
|
|
/* Make sure the timer value is stable. Stolen from acpi_pm.c */
|
|
do {
|
|
o2 = o1;
|
|
v1 = ctrl_inw(p->mapbase + TCNT);
|
|
v2 = ctrl_inw(p->mapbase + TCNT);
|
|
v3 = ctrl_inw(p->mapbase + TCNT);
|
|
o1 = ctrl_inb(p->mapcommon + TISRC) & p->ovf;
|
|
} while (unlikely((o1 != o2) || (v1 > v2 && v1 < v3)
|
|
|| (v2 > v3 && v2 < v1) || (v3 > v1 && v3 < v2)));
|
|
|
|
v2 |= 0x10000;
|
|
return v2;
|
|
}
|
|
|
|
|
|
static irqreturn_t timer16_interrupt(int irq, void *dev_id)
|
|
{
|
|
struct timer16_priv *p = (struct timer16_priv *)dev_id;
|
|
|
|
ctrl_outb(ctrl_inb(p->mapcommon + TISRA) & ~p->imfa,
|
|
p->mapcommon + TISRA);
|
|
p->total_cycles += 0x10000;
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static inline struct timer16_priv *cs_to_priv(struct clocksource *cs)
|
|
{
|
|
return container_of(cs, struct timer16_priv, cs);
|
|
}
|
|
|
|
static cycle_t timer16_clocksource_read(struct clocksource *cs)
|
|
{
|
|
struct timer16_priv *p = cs_to_priv(cs);
|
|
unsigned long flags, raw;
|
|
unsigned long value;
|
|
|
|
raw_spin_lock_irqsave(&p->lock, flags);
|
|
value = p->total_cycles;
|
|
raw = timer16_get_counter(p);
|
|
raw_spin_unlock_irqrestore(&p->lock, flags);
|
|
|
|
return value + raw;
|
|
}
|
|
|
|
static int timer16_enable(struct clocksource *cs)
|
|
{
|
|
struct timer16_priv *p = cs_to_priv(cs);
|
|
|
|
WARN_ON(p->cs_enabled);
|
|
|
|
p->total_cycles = 0;
|
|
ctrl_outw(0x0000, p->mapbase + TCNT);
|
|
ctrl_outb(0x83, p->mapbase + TCR);
|
|
ctrl_outb(ctrl_inb(p->mapcommon + TSTR) | p->enb,
|
|
p->mapcommon + TSTR);
|
|
|
|
p->cs_enabled = true;
|
|
return 0;
|
|
}
|
|
|
|
static void timer16_disable(struct clocksource *cs)
|
|
{
|
|
struct timer16_priv *p = cs_to_priv(cs);
|
|
|
|
WARN_ON(!p->cs_enabled);
|
|
|
|
ctrl_outb(ctrl_inb(p->mapcommon + TSTR) & ~p->enb,
|
|
p->mapcommon + TSTR);
|
|
|
|
p->cs_enabled = false;
|
|
}
|
|
|
|
#define REG_CH 0
|
|
#define REG_COMM 1
|
|
|
|
static int timer16_setup(struct timer16_priv *p, struct platform_device *pdev)
|
|
{
|
|
struct resource *res[2];
|
|
int ret, irq;
|
|
unsigned int ch;
|
|
|
|
p->pdev = pdev;
|
|
|
|
res[REG_CH] = platform_get_resource(p->pdev,
|
|
IORESOURCE_MEM, REG_CH);
|
|
res[REG_COMM] = platform_get_resource(p->pdev,
|
|
IORESOURCE_MEM, REG_COMM);
|
|
if (!res[REG_CH] || !res[REG_COMM]) {
|
|
dev_err(&p->pdev->dev, "failed to get I/O memory\n");
|
|
return -ENXIO;
|
|
}
|
|
irq = platform_get_irq(p->pdev, 0);
|
|
if (irq < 0) {
|
|
dev_err(&p->pdev->dev, "failed to get irq\n");
|
|
return irq;
|
|
}
|
|
|
|
p->clk = clk_get(&p->pdev->dev, "fck");
|
|
if (IS_ERR(p->clk)) {
|
|
dev_err(&p->pdev->dev, "can't get clk\n");
|
|
return PTR_ERR(p->clk);
|
|
}
|
|
of_property_read_u32(p->pdev->dev.of_node, "renesas,channel", &ch);
|
|
|
|
p->pdev = pdev;
|
|
p->mapbase = res[REG_CH]->start;
|
|
p->mapcommon = res[REG_COMM]->start;
|
|
p->enb = 1 << ch;
|
|
p->imfa = 1 << ch;
|
|
p->imiea = 1 << (4 + ch);
|
|
p->cs.name = pdev->name;
|
|
p->cs.rating = 200;
|
|
p->cs.read = timer16_clocksource_read;
|
|
p->cs.enable = timer16_enable;
|
|
p->cs.disable = timer16_disable;
|
|
p->cs.mask = CLOCKSOURCE_MASK(sizeof(unsigned long) * 8);
|
|
p->cs.flags = CLOCK_SOURCE_IS_CONTINUOUS;
|
|
|
|
ret = request_irq(irq, timer16_interrupt,
|
|
IRQF_TIMER, pdev->name, p);
|
|
if (ret < 0) {
|
|
dev_err(&p->pdev->dev, "failed to request irq %d\n", irq);
|
|
return ret;
|
|
}
|
|
|
|
clocksource_register_hz(&p->cs, clk_get_rate(p->clk) / 8);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int timer16_probe(struct platform_device *pdev)
|
|
{
|
|
struct timer16_priv *p = platform_get_drvdata(pdev);
|
|
|
|
if (p) {
|
|
dev_info(&pdev->dev, "kept as earlytimer\n");
|
|
return 0;
|
|
}
|
|
|
|
p = devm_kzalloc(&pdev->dev, sizeof(*p), GFP_KERNEL);
|
|
if (!p)
|
|
return -ENOMEM;
|
|
|
|
return timer16_setup(p, pdev);
|
|
}
|
|
|
|
static int timer16_remove(struct platform_device *pdev)
|
|
{
|
|
return -EBUSY;
|
|
}
|
|
|
|
static const struct of_device_id timer16_of_table[] = {
|
|
{ .compatible = "renesas,16bit-timer" },
|
|
{ }
|
|
};
|
|
static struct platform_driver timer16_driver = {
|
|
.probe = timer16_probe,
|
|
.remove = timer16_remove,
|
|
.driver = {
|
|
.name = "h8300h-16timer",
|
|
.of_match_table = of_match_ptr(timer16_of_table),
|
|
}
|
|
};
|
|
|
|
static int __init timer16_init(void)
|
|
{
|
|
return platform_driver_register(&timer16_driver);
|
|
}
|
|
|
|
static void __exit timer16_exit(void)
|
|
{
|
|
platform_driver_unregister(&timer16_driver);
|
|
}
|
|
|
|
subsys_initcall(timer16_init);
|
|
module_exit(timer16_exit);
|
|
MODULE_AUTHOR("Yoshinori Sato");
|
|
MODULE_DESCRIPTION("H8/300H 16bit Timer Driver");
|
|
MODULE_LICENSE("GPL v2");
|