diff options
Diffstat (limited to 'arch/m68k')
| -rw-r--r-- | arch/m68k/hp300/time.c | 37 |
1 files changed, 30 insertions, 7 deletions
diff --git a/arch/m68k/hp300/time.c b/arch/m68k/hp300/time.c index d30b03ea93a2..90982803a629 100644 --- a/arch/m68k/hp300/time.c +++ b/arch/m68k/hp300/time.c @@ -8,6 +8,7 @@ */ #include <asm/ptrace.h> +#include <linux/clocksource.h> #include <linux/types.h> #include <linux/init.h> #include <linux/sched.h> @@ -19,6 +20,18 @@ #include <asm/traps.h> #include <asm/blinken.h> +static u64 hp300_read_clk(struct clocksource *cs); + +static struct clocksource hp300_clk = { + .name = "timer", + .rating = 250, + .read = hp300_read_clk, + .mask = CLOCKSOURCE_MASK(32), + .flags = CLOCK_SOURCE_IS_CONTINUOUS, +}; + +static u32 clk_total; + /* Clock hardware definitions */ #define CLOCKBASE 0xf05f8000 @@ -32,9 +45,10 @@ #define CLKMSB3 0xD /* This is for machines which generate the exact clock. */ -#define USECS_PER_JIFFY (1000000/HZ) -#define INTVAL ((10000 / 4) - 1) +#define HP300_TIMER_CLOCK_FREQ 250000 +#define HP300_TIMER_CYCLES (HP300_TIMER_CLOCK_FREQ / HZ) +#define INTVAL (HP300_TIMER_CYCLES - 1) static irqreturn_t hp300_tick(int irq, void *dev_id) { @@ -45,6 +59,7 @@ static irqreturn_t hp300_tick(int irq, void *dev_id) local_irq_save(flags); in_8(CLOCKBASE + CLKSR); asm volatile ("movpw %1@(5),%0" : "=d" (tmp) : "a" (CLOCKBASE)); + clk_total += INTVAL; timer_routine(0, NULL); local_irq_restore(flags); @@ -53,20 +68,26 @@ static irqreturn_t hp300_tick(int irq, void *dev_id) return IRQ_HANDLED; } -u32 hp300_gettimeoffset(void) +static u64 hp300_read_clk(struct clocksource *cs) { - /* Read current timer 1 value */ + unsigned long flags; unsigned char lsb, msb1, msb2; - unsigned short ticks; + u32 ticks; + local_irq_save(flags); + /* Read current timer 1 value */ msb1 = in_8(CLOCKBASE + 5); lsb = in_8(CLOCKBASE + 7); msb2 = in_8(CLOCKBASE + 5); if (msb1 != msb2) /* A carry happened while we were reading. Read it again */ lsb = in_8(CLOCKBASE + 7); + ticks = INTVAL - ((msb2 << 8) | lsb); - return ((USECS_PER_JIFFY * ticks) / INTVAL) * 1000; + ticks += clk_total; + local_irq_restore(flags); + + return ticks; } void __init hp300_sched_init(irq_handler_t vector) @@ -76,9 +97,11 @@ void __init hp300_sched_init(irq_handler_t vector) asm volatile(" movpw %0,%1@(5)" : : "d" (INTVAL), "a" (CLOCKBASE)); - if (request_irq(IRQ_AUTO_6, hp300_tick, 0, "timer tick", vector)) + if (request_irq(IRQ_AUTO_6, hp300_tick, IRQF_TIMER, "timer tick", vector)) pr_err("Couldn't register timer interrupt\n"); out_8(CLOCKBASE + CLKCR2, 0x1); /* select CR1 */ out_8(CLOCKBASE + CLKCR1, 0x40); /* enable irq */ + + clocksource_register_hz(&hp300_clk, HP300_TIMER_CLOCK_FREQ); } |