aboutsummaryrefslogtreecommitdiff
path: root/arch/arm/mach-clps711x/time.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm/mach-clps711x/time.c')
-rw-r--r--arch/arm/mach-clps711x/time.c85
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,
+};