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-rw-r--r--arch/m68k/hp300/time.c78
1 files changed, 78 insertions, 0 deletions
diff --git a/arch/m68k/hp300/time.c b/arch/m68k/hp300/time.c
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+++ b/arch/m68k/hp300/time.c
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+/*
+ * linux/arch/m68k/hp300/time.c
+ *
+ * Copyright (C) 1998 Philip Blundell <philb@gnu.org>
+ *
+ * This file contains the HP300-specific time handling code.
+ */
+
+#include <asm/ptrace.h>
+#include <linux/types.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/kernel_stat.h>
+#include <linux/interrupt.h>
+#include <asm/machdep.h>
+#include <asm/irq.h>
+#include <asm/io.h>
+#include <asm/system.h>
+#include <asm/traps.h>
+#include <asm/blinken.h>
+#include "ints.h"
+
+/* Clock hardware definitions */
+
+#define CLOCKBASE 0xf05f8000
+
+#define CLKCR1 0x1
+#define CLKCR2 0x3
+#define CLKCR3 CLKCR1
+#define CLKSR CLKCR2
+#define CLKMSB1 0x5
+#define CLKMSB2 0x9
+#define CLKMSB3 0xD
+
+/* This is for machines which generate the exact clock. */
+#define USECS_PER_JIFFY (1000000/HZ)
+
+#define INTVAL ((10000 / 4) - 1)
+
+static irqreturn_t hp300_tick(int irq, void *dev_id, struct pt_regs *regs)
+{
+ unsigned long tmp;
+ irqreturn_t (*vector)(int, void *, struct pt_regs *) = dev_id;
+ in_8(CLOCKBASE + CLKSR);
+ asm volatile ("movpw %1@(5),%0" : "=d" (tmp) : "a" (CLOCKBASE));
+ /* Turn off the network and SCSI leds */
+ blinken_leds(0, 0xe0);
+ return vector(irq, NULL, regs);
+}
+
+unsigned long hp300_gettimeoffset(void)
+{
+ /* Read current timer 1 value */
+ unsigned char lsb, msb1, msb2;
+ unsigned short ticks;
+
+ 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;
+}
+
+void __init hp300_sched_init(irqreturn_t (*vector)(int, void *, struct pt_regs *))
+{
+ out_8(CLOCKBASE + CLKCR2, 0x1); /* select CR1 */
+ out_8(CLOCKBASE + CLKCR1, 0x1); /* reset */
+
+ asm volatile(" movpw %0,%1@(5)" : : "d" (INTVAL), "a" (CLOCKBASE));
+
+ cpu_request_irq(6, hp300_tick, IRQ_FLG_STD, "timer tick", vector);
+
+ out_8(CLOCKBASE + CLKCR2, 0x1); /* select CR1 */
+ out_8(CLOCKBASE + CLKCR1, 0x40); /* enable irq */
+}
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