include/sys/pit.h

   1 /*
   2  * CDDL HEADER START
   3  *
   4  * The contents of this file are subject to the terms of the
   5  * Common Development and Distribution License (the "License").
   6  * You may not use this file except in compliance with the License.
   7  *
   8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
   9  * or http://www.opensolaris.org/os/licensing.
  10  * See the License for the specific language governing permissions
  11  * and limitations under the License.
  12  *
  13  * When distributing Covered Code, include this CDDL HEADER in each
  14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  15  * If applicable, add the following below this CDDL HEADER, with the
  16  * fields enclosed by brackets "[]" replaced with your own identifying
  17  * information: Portions Copyright [yyyy] [name of copyright owner]
  18  *
  19  * CDDL HEADER END
  20  */
  21 /*      Copyright (c) 1990, 1991 UNIX System Laboratories, Inc. */
  22 /*      Copyright (c) 1984, 1986, 1987, 1988, 1989, 1990 AT&T   */
  23 /*      All Rights Reserved     */
  24
  25 /*
  26  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
  27  * Use is subject to license terms.
  28  */
  29
  30 #ifndef _SYS_PIT_H
  31 #define _SYS_PIT_H
  32
  33 #pragma ident   "%Z%%M% %I%     %E% SMI"
  34
  35 #ifdef __cplusplus
  36 extern "C" {
  37 #endif
  38
  39 /* Definitions for 8254 Programmable Interrupt Timer ports on AT 386 */
  40 #define PITCTR0_PORT    0x40            /* counter 0 port */
  41 #define PITCTR1_PORT    0x41            /* counter 1 port */
  42 #define PITCTR2_PORT    0x42            /* counter 2 port */
  43 #define PITCTL_PORT     0x43            /* PIT control port */
  44 #define PITAUX_PORT     0x61            /* PIT auxiliary port */
  45 #define SANITY_CTR0     0x48            /* sanity timer counter */
  46 #define SANITY_CTL      0x4B            /* sanity control word */
  47 #define SANITY_CHECK    0x461           /* bit 7 set if sanity timer went off */
  48 #define FAILSAFE_NMI    0x80            /* to test if sanity timer went off */
  49 #define ENABLE_SANITY   0x04            /* Enables sanity clock NMI ints */
  50 #define RESET_SANITY    0x00            /* resets sanity NMI interrupt */
  51
  52 /* PIT Status Byte */
  53
  54 #define PITSTAT_OUTPUT  7               /* OUTPUT status bit */
  55 #define PITSTAT_NULLCNT 6               /* NULL COUNT status bit */
  56
  57 /* Definitions for 8254 commands */
  58
  59 #define PIT_READBACK    0xc0            /* read-back command */
  60 #define PIT_READBACKC0  0x02            /* enable read-back for counter 0 */
  61
  62 /* Following are used for Timer 0 */
  63 #define PIT_C0          0x00            /* select counter 0 */
  64 #define PIT_LOADMODE    0x30            /* load least significant byte */
  65                                         /* followed by most significant byte */
  66 #define PIT_NDIVMODE    0x04            /* divide by N counter */
  67 #define PIT_SQUAREMODE  0x06            /* square-wave mode */
  68 #define PIT_ENDSIGMODE  0x00            /* assert OUT at end-of-count mode */
  69
  70 /* Used for Timer 1. Used for delay calculations in countdown mode */
  71 #define PIT_C1          0x40            /* select counter 1 */
  72 #define PIT_READMODE    0x30            /* read or load least significant */
  73                                         /* byte followed by most significant */
  74 #define PIT_RATEMODE    0x06            /* square-wave mode for USART */
  75
  76 #define PIT_C2          0x80            /* select counter 2 */
  77
  78 #define SANITY_NUM      0xFFFF          /* Sanity timer fires every .2 secs */
  79 /* bits used in auxiliary control port for timer 2 */
  80 #define PITAUX_GATE2    0x01            /* aux port, PIT gate 2 input */
  81 #define PITAUX_OUT2     0x02            /* aux port, PIT clock out 2 enable */
  82 #define PIT_HZ          1193182         /* 8254's cycles per second */
  83
  84 #ifdef __cplusplus
  85 }
  86 #endif
  87
  88 #endif  /* _SYS_PIT_H */