arch/x86/include/sys/polled_io.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, Version 1.0 only
   6  * (the "License").  You may not use this file except in compliance
   7  * with the License.
   8  *
   9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
  10  * or http://www.opensolaris.org/os/licensing.
  11  * See the License for the specific language governing permissions
  12  * and limitations under the License.
  13  *
  14  * When distributing Covered Code, include this CDDL HEADER in each
  15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
  16  * If applicable, add the following below this CDDL HEADER, with the
  17  * fields enclosed by brackets "[]" replaced with your own identifying
  18  * information: Portions Copyright [yyyy] [name of copyright owner]
  19  *
  20  * CDDL HEADER END
  21  */
  22 /*
  23  * Copyright (c) 1998-1999 by Sun Microsystems, Inc.
  24  * All rights reserved.
  25  */
  26
  27 #ifndef _SYS_POLLED_IO_H
  28 #define _SYS_POLLED_IO_H
  29
  30 #pragma ident   "%Z%%M% %I%     %E% SMI"
  31
  32 #ifdef  __cplusplus
  33 extern "C" {
  34 #endif
  35
  36 typedef struct polled_device {
  37         /*
  38          * This lock is only used to lock writing from
  39          * the fields on the structure.  The values in the
  40          * structure can be read under obp, so the lock
  41          * isn't valid then.
  42          */
  43         kmutex_t        polled_device_lock;
  44
  45         /*
  46          * When we switch over the console, this is the old value
  47          * so that we can restore it later.
  48          */
  49         uint64_t        polled_old_handle;
  50
  51         /*
  52          * Pointer to registerd polled I/O callbacks.
  53          */
  54         cons_polledio_t *polled_io;
  55
  56 } polled_device_t;
  57
  58 _NOTE(MUTEX_PROTECTS_DATA(polled_device_t::polled_device_lock,
  59         polled_device_t))
  60
  61 /*
  62  * The lower layers did not find any characters.
  63  */
  64 #define CIF_NO_CHARACTERS       ((uint_t)-2)
  65
  66 /*
  67  * Every CIF has at least 3 arguments:  0 (name), 1 (in args), and 2 (out args).
  68  */
  69 #define CIF_MIN_SIZE            3
  70
  71 #define CIF_NAME                0       /* name of function */
  72 #define CIF_NUMBER_IN_ARGS      1       /* number of arguments passed in */
  73 #define CIF_NUMBER_OUT_ARGS     2       /* number of arguments for return */
  74 #define CIF_BUFFER_ADDRESS      3       /* address to write data */
  75 #define CIF_BUFFER_LENGTH       4       /* length of BUFFER_ADDRESS */
  76 #define CIF_RETURN_VALUE        5       /* return status of operation */
  77
  78
  79 /*
  80  * This is the size of the structure that we are expecting to be passed
  81  * in.  This is based on CIF_MIN_SIZE + address + length + value (see above)
  82  */
  83 #define CIF_SIZE                6       /* size of cif structure */
  84
  85 /*
  86  * These are the types of polled I/O that this module handles.
  87  */
  88 typedef enum polled_io_console_type {
  89         POLLED_IO_CONSOLE_INPUT = 0,
  90         POLLED_IO_CONSOLE_OUTPUT = 1
  91 } polled_io_console_type_t;
  92
  93 /*
  94  * Initialize the polled I/O kernel structures
  95  */
  96 void    polled_io_init(void);
  97
  98 /*
  99  * De-initialize the polled I/O kernel structures
 100  */
 101 void    polled_io_fini(void);
 102
 103 /*
 104  * Register a device to be used as a console for OBP.
 105  */
 106 int     polled_io_register_callbacks(cons_polledio_t *, int);
 107
 108 /*
 109  * Unregister a device to be used as a console for OBP.
 110  */
 111 int     polled_io_unregister_callbacks(cons_polledio_t *, int);
 112
 113 #ifdef  __cplusplus
 114 }
 115 #endif
 116
 117 #endif  /* _SYS_POLLED_IO_H */