diff options
Diffstat (limited to 'arch/arm/mach-clps711x/time.c')
-rw-r--r-- | arch/arm/mach-clps711x/time.c | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/arch/arm/mach-clps711x/time.c b/arch/arm/mach-clps711x/time.c new file mode 100644 index 00000000000..383d4e0c6e3 --- /dev/null +++ b/arch/arm/mach-clps711x/time.c @@ -0,0 +1,85 @@ +/* + * linux/arch/arm/mach-clps711x/time.c + * + * Copyright (C) 2001 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 version 2 as + * published by the Free Software Foundation. + * + * 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/timex.h> +#include <linux/init.h> +#include <linux/interrupt.h> +#include <linux/sched.h> + +#include <asm/hardware.h> +#include <asm/irq.h> +#include <asm/leds.h> +#include <asm/io.h> +#include <asm/hardware/clps7111.h> + +#include <asm/mach/time.h> + + +/* + * gettimeoffset() returns time since last timer tick, in usecs. + * + * 'LATCH' is hwclock ticks (see CLOCK_TICK_RATE in timex.h) per jiffy. + * 'tick' is usecs per jiffy. + */ +static unsigned long clps711x_gettimeoffset(void) +{ + unsigned long hwticks; + hwticks = LATCH - (clps_readl(TC2D) & 0xffff); /* since last underflow */ + return (hwticks * (tick_nsec / 1000)) / LATCH; +} + +/* + * IRQ handler for the timer + */ +static irqreturn_t +p720t_timer_interrupt(int irq, void *dev_id, struct pt_regs *regs) +{ + write_seqlock(&xtime_lock); + timer_tick(regs); + write_sequnlock(&xtime_lock); + return IRQ_HANDLED; +} + +static struct irqaction clps711x_timer_irq = { + .name = "CLPS711x Timer Tick", + .flags = SA_INTERRUPT, + .handler = p720t_timer_interrupt +}; + +static void __init clps711x_timer_init(void) +{ + struct timespec tv; + unsigned int syscon; + + syscon = clps_readl(SYSCON1); + syscon |= SYSCON1_TC2S | SYSCON1_TC2M; + clps_writel(syscon, SYSCON1); + + clps_writel(LATCH-1, TC2D); /* 512kHz / 100Hz - 1 */ + + setup_irq(IRQ_TC2OI, &clps711x_timer_irq); + + tv.tv_nsec = 0; + tv.tv_sec = clps_readl(RTCDR); + do_settimeofday(&tv); +} + +struct sys_timer clps711x_timer = { + .init = clps711x_timer_init, + .offset = clps711x_gettimeoffset, +}; |