Initial revision

1 files changed, 62 insertions, 0 deletions

diff --git a/src/include/timer.h b/src/include/timer.h
new file mode 100644
index 000000000..6b68f5f38
--- /dev/null
+++ b/src/include/timer.h
@@ -0,0 +1,62 @@
+/* Defines for routines to implement a low-overhead timer for drivers */
+
+ /*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2, or (at
+ * your option) any later version.
+ */
+
+#ifndef	TIMER_H
+#define TIMER_H
+
+/* Ports for the 8254 timer chip */
+#define	TIMER2_PORT	0x42
+#define	TIMER_MODE_PORT	0x43
+
+/* Meaning of the mode bits */
+#define	TIMER0_SEL	0x00
+#define	TIMER1_SEL	0x40
+#define	TIMER2_SEL	0x80
+#define	READBACK_SEL	0xC0
+
+#define	LATCH_COUNT	0x00
+#define	LOBYTE_ACCESS	0x10
+#define	HIBYTE_ACCESS	0x20
+#define	WORD_ACCESS	0x30
+
+#define	MODE0		0x00
+#define	MODE1		0x02
+#define	MODE2		0x04
+#define	MODE3		0x06
+#define	MODE4		0x08
+#define	MODE5		0x0A
+
+#define	BINARY_COUNT	0x00
+#define	BCD_COUNT	0x01
+
+/* Timers tick over at this rate */
+#define CLOCK_TICK_RATE	1193180U
+#define	TICKS_PER_MS	(CLOCK_TICK_RATE/1000)
+
+/* Parallel Peripheral Controller Port B */
+#define	PPC_PORTB	0x61
+
+/* Meaning of the port bits */
+#define	PPCB_T2OUT	0x20	/* Bit 5 */
+#define	PPCB_SPKR	0x02	/* Bit 1 */
+#define	PPCB_T2GATE	0x01	/* Bit 0 */
+
+/* Ticks must be between 0 and 65535 (0 == 65536)
+   because it is a 16 bit counter */
+extern void load_timer2(unsigned int ticks);
+extern inline int timer2_running(void);
+extern void waiton_timer2(unsigned int ticks);
+
+extern void setup_timers(void);
+extern void ndelay(unsigned int nsecs);
+extern void udelay(unsigned int usecs);
+extern void mdelay(unsigned int msecs);
+
+
+#endif	/* TIMER_H */