1 /*        $NetBSD: weaselreg.h,v 1.8 2022/04/11 20:57:38 andvar Exp $ */
2 
3 /*-
4  * Copyright (c) 2000 Zembu Labs, Inc.
5  * All rights reserved.
6  *
7  * Author: Jason R. Thorpe <thorpej@zembu.com>
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. All advertising materials mentioning features or use of this software
18  *    must display the following acknowledgement:
19  *        This product includes software developed by Zembu Labs, Inc.
20  * 4. Neither the name of Zembu Labs nor the names of its employees may
21  *    be used to endorse or promote products derived from this software
22  *    without specific prior written permission.
23  *
24  * THIS SOFTWARE IS PROVIDED BY ZEMBU LABS, INC. ``AS IS'' AND ANY EXPRESS
25  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WAR-
26  * RANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DIS-
27  * CLAIMED.  IN NO EVENT SHALL ZEMBU LABS BE LIABLE FOR ANY DIRECT, INDIRECT,
28  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
29  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
30  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
31  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
32  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
33  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34  */
35 
36 /*
37  * Register and firmware communication definitions for the
38  * Middle Digital, Inc. PC-Weasel serial console board.
39  */
40 
41 /*
42  * Current versions of the PC-Weasel emulate a Monochrome Display
43  * Adapter.  The framebuffer is at the standard ISA framebuffer
44  * location (0xb0000).  At the end of the viewable framebuffer area
45  * is a control register space.
46  */
47 
48 #define   WEASEL_WDT_SEMAPHORE                    0x0fa0
49 
50 #define   WEASEL_CONFIG_BLOCK           0x0fa1
51 
52 #define WEASEL_WDT_TICKLE               0x0fa2
53 
54 #define   WEASEL_MISC_COMMAND           0x0fcd
55 
56 #define   WEASEL_MISC_RESPONSE                    0x0fce
57 
58 /*
59  * Layout of the PC-Weasel configuration block.  This is taken
60  * more or less right out of the PC-Weasel manual, page 52.
61  */
62 struct weasel_config_block {
63           u_int8_t  cfg_version;        /* configuration version */
64 
65 #define   CFG_VERSION_1_0               0x01
66 #define   CFG_VERSION_1_1               0x02
67 
68           u_int8_t  weasel_attn;        /* Weasel attention character */
69           u_int8_t  debug;              /* debug level */
70           u_int8_t  reset_pc_on_boot;/* reset PC on Weasel boot */
71           u_int8_t  duart_baud;         /* baud rate of DUART */
72           u_int8_t  duart_parity;       /* 0 none, 1 even, 2 odd */
73           u_int8_t  duart_bits;         /* 7 or 8 */
74 
75           /*
76            * Unfortunately, between cfg_version 1 and 2, the semantics
77            * of this variable changed.
78            *
79            *        cfg_version 1:
80            *
81            *                  0 == always emulate
82            *                  1 == autoswitch
83            *
84            *        cfg_version 2:
85            *
86            *                  0 == always emulate
87            *                  1 == always serial
88            *                  2 == autoswitch
89            */
90           u_int8_t  enable_duart_switching;
91           u_int8_t  wdt_allow;          /* 0 disable, 1 allow */
92           u_int16_t wdt_msec; /* watchdog timer period */
93           u_int8_t  duart_flow;         /* 1 rts/cts, 0 none */
94           u_int8_t  break_passthru;     /* BREAK is passed through */
95           u_int8_t  obsolete[30];       /* reserved for future use */
96           u_int8_t  cksum;              /* arithmetic sum -> reserved */
97 } __packed;
98 
99 /*
100  * Commands that can be written to the MISC_COMMAND register.
101  */
102 
103 #define   OS_READY  0x00                /* ready for commands */
104 
105 #define   OS_UART_CLEAR       0x01                /* clear response for OS_UART_QUERY */
106 
107 #define   OS_UART_QUERY       0x02                /* query Weasel UART setting */
108 #define   UART_QUERY_DIS      0x00                /* UART is disabled */
109 #define   UART_QUERY_3f8      0x01                /* UART at 0x3f8 */
110 #define   UART_QUERY_2F8      0x02                /* UART at 0x2f8 */
111 #define   UART_QUERY_3e8      0x03                /* UART at 0x3e8 */
112 #define   UART_QUERY_2e8      0x04                /* UART at 0x2e8 */
113 
114 #define   OS_CONFIG_COPY      0x03                /* copy config to offscreen space */
115 #define OS_WDT_QUERY    0x04            /* query watchdog state. 0=off 1=on */
116 
117 #define   OS_NOP              0x07
118 
119 /*
120  * The watchdog timer on the PC-Weasel is enabled/disabled (it's a toggle)
121  * using the WDT_SEMAPHORE register in the offscreen area.  The semaphore
122  * is also used to service the watchdog.
123  *
124  * To toggle the watchdog:
125  *
126  *        for (new_state = old_state; new_state == old_state;) {
127  *                  WDT_SEMAPHORE = 0x22;
128  *                  delay(1500);
129  *                  if (WDT_SEMAPHORE == 0xea) {
130  *                            WDT_SEMAPHORE = 0x2f;
131  *                            delay(1500);
132  *                            if (WDT_SEMAPHORE == 0xae) {
133  *                                      WDT_SEMAPHORE = 0x37;
134  *                                      delay(1500);
135  *                                      new_state = WDT_SEMAPHORE;
136  *                            }
137  *                  }
138  *        }
139  *
140  * To service the watchdog when armed:
141  *
142  *        tmp = WDT_SEMPAPHORE;
143  *        WDT_SEMAPHORE ~= tmp;
144  */
145 #define WDT_ATTENTION   0x22    /* get the attention of the WDT state engine */
146 #define WDT_OK          0xae    /* we get back an acknowledgement */
147 #define WDT_ENABLE      0xf1    /* the command to arm to watchdog. */
148 #define WDT_DISABLE     0xf4    /* the command to disarm the watchdog. */
149 
150