diff options
Diffstat (limited to 'drivers/clocksource/h8300_timer8.c')
| -rw-r--r-- | drivers/clocksource/h8300_timer8.c | 264 |
1 files changed, 81 insertions, 183 deletions
diff --git a/drivers/clocksource/h8300_timer8.c b/drivers/clocksource/h8300_timer8.c index 44375d8b9..c151941e1 100644 --- a/drivers/clocksource/h8300_timer8.c +++ b/drivers/clocksource/h8300_timer8.c @@ -8,19 +8,15 @@ */ #include <linux/errno.h> -#include <linux/sched.h> #include <linux/kernel.h> #include <linux/interrupt.h> #include <linux/init.h> -#include <linux/platform_device.h> -#include <linux/slab.h> #include <linux/clockchips.h> -#include <linux/module.h> #include <linux/clk.h> #include <linux/io.h> #include <linux/of.h> - -#include <asm/irq.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> #define _8TCR 0 #define _8TCSR 2 @@ -28,126 +24,74 @@ #define TCORB 6 #define _8TCNT 8 -#define FLAG_REPROGRAM (1 << 0) -#define FLAG_SKIPEVENT (1 << 1) -#define FLAG_IRQCONTEXT (1 << 2) +#define CMIEA 6 +#define CMFA 6 + #define FLAG_STARTED (1 << 3) -#define ONESHOT 0 -#define PERIODIC 1 +#define SCALE 64 -#define RELATIVE 0 -#define ABSOLUTE 1 +#define bset(b, a) iowrite8(ioread8(a) | (1 << (b)), (a)) +#define bclr(b, a) iowrite8(ioread8(a) & ~(1 << (b)), (a)) struct timer8_priv { - struct platform_device *pdev; struct clock_event_device ced; - struct irqaction irqaction; - unsigned long mapbase; - raw_spinlock_t lock; + void __iomem *mapbase; unsigned long flags; unsigned int rate; - unsigned int tcora; - struct clk *pclk; }; -static unsigned long timer8_get_counter(struct timer8_priv *p) -{ - unsigned long v1, v2, v3; - int o1, o2; - - o1 = ctrl_inb(p->mapbase + _8TCSR) & 0x20; - - /* Make sure the timer value is stable. Stolen from acpi_pm.c */ - do { - o2 = o1; - v1 = ctrl_inw(p->mapbase + _8TCNT); - v2 = ctrl_inw(p->mapbase + _8TCNT); - v3 = ctrl_inw(p->mapbase + _8TCNT); - o1 = ctrl_inb(p->mapbase + _8TCSR) & 0x20; - } while (unlikely((o1 != o2) || (v1 > v2 && v1 < v3) - || (v2 > v3 && v2 < v1) || (v3 > v1 && v3 < v2))); - - v2 |= o1 << 10; - return v2; -} - static irqreturn_t timer8_interrupt(int irq, void *dev_id) { struct timer8_priv *p = dev_id; - ctrl_outb(ctrl_inb(p->mapbase + _8TCSR) & ~0x40, - p->mapbase + _8TCSR); - p->flags |= FLAG_IRQCONTEXT; - ctrl_outw(p->tcora, p->mapbase + TCORA); - if (!(p->flags & FLAG_SKIPEVENT)) { - if (clockevent_state_oneshot(&p->ced)) - ctrl_outw(0x0000, p->mapbase + _8TCR); - p->ced.event_handler(&p->ced); - } - p->flags &= ~(FLAG_SKIPEVENT | FLAG_IRQCONTEXT); + if (clockevent_state_oneshot(&p->ced)) + iowrite16be(0x0000, p->mapbase + _8TCR); + + p->ced.event_handler(&p->ced); + + bclr(CMFA, p->mapbase + _8TCSR); return IRQ_HANDLED; } static void timer8_set_next(struct timer8_priv *p, unsigned long delta) { - unsigned long flags; - unsigned long now; - - raw_spin_lock_irqsave(&p->lock, flags); if (delta >= 0x10000) - dev_warn(&p->pdev->dev, "delta out of range\n"); - now = timer8_get_counter(p); - p->tcora = delta; - ctrl_outb(ctrl_inb(p->mapbase + _8TCR) | 0x40, p->mapbase + _8TCR); - if (delta > now) - ctrl_outw(delta, p->mapbase + TCORA); - else - ctrl_outw(now + 1, p->mapbase + TCORA); - - raw_spin_unlock_irqrestore(&p->lock, flags); + pr_warn("delta out of range\n"); + bclr(CMIEA, p->mapbase + _8TCR); + iowrite16be(delta, p->mapbase + TCORA); + iowrite16be(0x0000, p->mapbase + _8TCNT); + bclr(CMFA, p->mapbase + _8TCSR); + bset(CMIEA, p->mapbase + _8TCR); } static int timer8_enable(struct timer8_priv *p) { - p->rate = clk_get_rate(p->pclk) / 64; - ctrl_outw(0xffff, p->mapbase + TCORA); - ctrl_outw(0x0000, p->mapbase + _8TCNT); - ctrl_outw(0x0c02, p->mapbase + _8TCR); + iowrite16be(0xffff, p->mapbase + TCORA); + iowrite16be(0x0000, p->mapbase + _8TCNT); + iowrite16be(0x0c02, p->mapbase + _8TCR); return 0; } static int timer8_start(struct timer8_priv *p) { - int ret = 0; - unsigned long flags; - - raw_spin_lock_irqsave(&p->lock, flags); - - if (!(p->flags & FLAG_STARTED)) - ret = timer8_enable(p); + int ret; - if (ret) - goto out; - p->flags |= FLAG_STARTED; + if ((p->flags & FLAG_STARTED)) + return 0; - out: - raw_spin_unlock_irqrestore(&p->lock, flags); + ret = timer8_enable(p); + if (!ret) + p->flags |= FLAG_STARTED; return ret; } static void timer8_stop(struct timer8_priv *p) { - unsigned long flags; - - raw_spin_lock_irqsave(&p->lock, flags); - - ctrl_outw(0x0000, p->mapbase + _8TCR); - - raw_spin_unlock_irqrestore(&p->lock, flags); + iowrite16be(0x0000, p->mapbase + _8TCR); } static inline struct timer8_priv *ced_to_priv(struct clock_event_device *ced) @@ -155,7 +99,7 @@ static inline struct timer8_priv *ced_to_priv(struct clock_event_device *ced) return container_of(ced, struct timer8_priv, ced); } -static void timer8_clock_event_start(struct timer8_priv *p, int periodic) +static void timer8_clock_event_start(struct timer8_priv *p, unsigned long delta) { struct clock_event_device *ced = &p->ced; @@ -166,7 +110,7 @@ static void timer8_clock_event_start(struct timer8_priv *p, int periodic) ced->max_delta_ns = clockevent_delta2ns(0xffff, ced); ced->min_delta_ns = clockevent_delta2ns(0x0001, ced); - timer8_set_next(p, periodic?(p->rate + HZ/2) / HZ:0x10000); + timer8_set_next(p, delta); } static int timer8_clock_event_shutdown(struct clock_event_device *ced) @@ -179,9 +123,9 @@ static int timer8_clock_event_periodic(struct clock_event_device *ced) { struct timer8_priv *p = ced_to_priv(ced); - dev_info(&p->pdev->dev, "used for periodic clock events\n"); + pr_info("%s: used for periodic clock events\n", ced->name); timer8_stop(p); - timer8_clock_event_start(p, PERIODIC); + timer8_clock_event_start(p, (p->rate + HZ/2) / HZ); return 0; } @@ -190,9 +134,9 @@ static int timer8_clock_event_oneshot(struct clock_event_device *ced) { struct timer8_priv *p = ced_to_priv(ced); - dev_info(&p->pdev->dev, "used for oneshot clock events\n"); + pr_info("%s: used for oneshot clock events\n", ced->name); timer8_stop(p); - timer8_clock_event_start(p, ONESHOT); + timer8_clock_event_start(p, 0x10000); return 0; } @@ -208,110 +152,64 @@ static int timer8_clock_event_next(unsigned long delta, return 0; } -static int timer8_setup(struct timer8_priv *p, - struct platform_device *pdev) +static struct timer8_priv timer8_priv = { + .ced = { + .name = "h8300_8timer", + .features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT, + .rating = 200, + .set_next_event = timer8_clock_event_next, + .set_state_shutdown = timer8_clock_event_shutdown, + .set_state_periodic = timer8_clock_event_periodic, + .set_state_oneshot = timer8_clock_event_oneshot, + }, +}; + +static void __init h8300_8timer_init(struct device_node *node) { - struct resource *res; + void __iomem *base; int irq; - int ret; + struct clk *clk; - p->pdev = pdev; - - res = platform_get_resource(p->pdev, IORESOURCE_MEM, 0); - if (!res) { - dev_err(&p->pdev->dev, "failed to get I/O memory\n"); - return -ENXIO; + clk = of_clk_get(node, 0); + if (IS_ERR(clk)) { + pr_err("failed to get clock for clockevent\n"); + return; } - irq = platform_get_irq(p->pdev, 0); - if (irq < 0) { - dev_err(&p->pdev->dev, "failed to get irq\n"); - return -ENXIO; + base = of_iomap(node, 0); + if (!base) { + pr_err("failed to map registers for clockevent\n"); + goto free_clk; } - p->mapbase = res->start; - - p->irqaction.name = dev_name(&p->pdev->dev); - p->irqaction.handler = timer8_interrupt; - p->irqaction.dev_id = p; - p->irqaction.flags = IRQF_TIMER; - - p->pclk = clk_get(&p->pdev->dev, "fck"); - if (IS_ERR(p->pclk)) { - dev_err(&p->pdev->dev, "can't get clk\n"); - return PTR_ERR(p->pclk); + irq = irq_of_parse_and_map(node, 0); + if (!irq) { + pr_err("failed to get irq for clockevent\n"); + goto unmap_reg; } - p->ced.name = pdev->name; - p->ced.features = CLOCK_EVT_FEAT_PERIODIC | - CLOCK_EVT_FEAT_ONESHOT; - p->ced.rating = 200; - p->ced.cpumask = cpumask_of(0); - p->ced.set_next_event = timer8_clock_event_next; - p->ced.set_state_shutdown = timer8_clock_event_shutdown; - p->ced.set_state_periodic = timer8_clock_event_periodic; - p->ced.set_state_oneshot = timer8_clock_event_oneshot; - - ret = setup_irq(irq, &p->irqaction); - if (ret < 0) { - dev_err(&p->pdev->dev, - "failed to request irq %d\n", irq); - return ret; - } - clockevents_register_device(&p->ced); - platform_set_drvdata(pdev, p); + timer8_priv.mapbase = base; - return 0; -} - -static int timer8_probe(struct platform_device *pdev) -{ - struct timer8_priv *p = platform_get_drvdata(pdev); - - if (p) { - dev_info(&pdev->dev, "kept as earlytimer\n"); - return 0; + timer8_priv.rate = clk_get_rate(clk) / SCALE; + if (!timer8_priv.rate) { + pr_err("Failed to get rate for the clocksource\n"); + goto unmap_reg; } - p = devm_kzalloc(&pdev->dev, sizeof(*p), GFP_KERNEL); - if (!p) - return -ENOMEM; - - return timer8_setup(p, pdev); -} - -static int timer8_remove(struct platform_device *pdev) -{ - return -EBUSY; -} - -static const struct of_device_id timer8_of_table[] __maybe_unused = { - { .compatible = "renesas,8bit-timer" }, - { } -}; - -MODULE_DEVICE_TABLE(of, timer8_of_table); -static struct platform_driver timer8_driver = { - .probe = timer8_probe, - .remove = timer8_remove, - .driver = { - .name = "h8300-8timer", - .of_match_table = of_match_ptr(timer8_of_table), + if (request_irq(irq, timer8_interrupt, IRQF_TIMER, + timer8_priv.ced.name, &timer8_priv) < 0) { + pr_err("failed to request irq %d for clockevent\n", irq); + goto unmap_reg; } -}; -static int __init timer8_init(void) -{ - return platform_driver_register(&timer8_driver); -} + clockevents_config_and_register(&timer8_priv.ced, + timer8_priv.rate, 1, 0x0000ffff); -static void __exit timer8_exit(void) -{ - platform_driver_unregister(&timer8_driver); + return; +unmap_reg: + iounmap(base); +free_clk: + clk_put(clk); } -subsys_initcall(timer8_init); -module_exit(timer8_exit); -MODULE_AUTHOR("Yoshinori Sato"); -MODULE_DESCRIPTION("H8/300 8bit Timer Driver"); -MODULE_LICENSE("GPL v2"); +CLOCKSOURCE_OF_DECLARE(h8300_8bit, "renesas,8bit-timer", h8300_8timer_init); |