1 /* $NetBSD: zsvar.h,v 1.9 2005/12/11 12:16:54 christos Exp $ */ 2 3 /* 4 * Copyright (c) 1992, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This software was developed by the Computer Systems Engineering group 8 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 9 * contributed to Berkeley. 10 * 11 * All advertising materials mentioning features or use of this software 12 * must display the following acknowledgement: 13 * This product includes software developed by the University of 14 * California, Lawrence Berkeley Laboratory. 15 * 16 * Redistribution and use in source and binary forms, with or without 17 * modification, are permitted provided that the following conditions 18 * are met: 19 * 1. Redistributions of source code must retain the above copyright 20 * notice, this list of conditions and the following disclaimer. 21 * 2. Redistributions in binary form must reproduce the above copyright 22 * notice, this list of conditions and the following disclaimer in the 23 * documentation and/or other materials provided with the distribution. 24 * 3. Neither the name of the University nor the names of its contributors 25 * may be used to endorse or promote products derived from this software 26 * without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 38 * SUCH DAMAGE. 39 * 40 * @(#)zsvar.h 8.1 (Berkeley) 6/11/93 41 */ 42 43 /*- 44 * Copyright (c) 1995 The NetBSD Foundation, Inc. (Atari modifications) 45 * All rights reserved. 46 * 47 * This code is derived from software contributed to The NetBSD Foundation 48 * by Leo Weppelman. 49 * 50 * Redistribution and use in source and binary forms, with or without 51 * modification, are permitted provided that the following conditions 52 * are met: 53 * 1. Redistributions of source code must retain the above copyright 54 * notice, this list of conditions and the following disclaimer. 55 * 2. Redistributions in binary form must reproduce the above copyright 56 * notice, this list of conditions and the following disclaimer in the 57 * documentation and/or other materials provided with the distribution. 58 * 3. Neither the name of The NetBSD Foundation nor the names of its 59 * contributors may be used to endorse or promote products derived 60 * from this software without specific prior written permission. 61 * 62 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 63 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 64 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 65 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 66 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 67 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 68 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 69 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 70 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 71 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 72 * POSSIBILITY OF SUCH DAMAGE. 73 */ 74 75 /* 76 * Register layout is machine-dependent... 77 */ 78 79 struct zschan { 80 u_char zc_xxx0; 81 volatile u_char zc_csr; /* ctrl,status, and indirect access */ 82 u_char zc_xxx1; 83 volatile u_char zc_data; /* data */ 84 }; 85 86 struct zsdevice { 87 struct zschan zs_chan[2]; 88 }; 89 90 /* 91 * Software state, per zs channel. 92 * 93 * The zs chip has insufficient buffering, so we provide a software 94 * buffer using a two-level interrupt scheme. The hardware (high priority) 95 * interrupt simply grabs the `cause' of the interrupt and stuffs it into 96 * a ring buffer. It then schedules a software interrupt; the latter 97 * empties the ring as fast as it can, hoping to avoid overflow. 98 * 99 * Interrupts can happen because of: 100 * - received data; 101 * - transmit pseudo-DMA done; and 102 * - status change. 103 * These are all stored together in the (single) ring. The size of the 104 * ring is a power of two, to make % operations fast. Since we need two 105 * bits to distinguish the interrupt type, and up to 16 for the received 106 * data plus RR1 status, we use 32 bits per ring entry. 107 * 108 * When the value is a character + RR1 status, the character is in the 109 * upper 8 bits of the RR1 status. 110 */ 111 #define ZLRB_RING_SIZE 4096 /* ZS line ring buffer size */ 112 #define ZLRB_RING_MASK 4095 /* mask for same */ 113 114 /* 0 is reserved (means "no interrupt") */ 115 #define ZRING_RINT 1 /* receive data interrupt */ 116 #define ZRING_XINT 2 /* transmit done interrupt */ 117 #define ZRING_SINT 3 /* status change interrupt */ 118 119 #define ZRING_TYPE(x) ((x) & 3) 120 #define ZRING_VALUE(x) ((x) >> 8) 121 #define ZRING_MAKE(t, v) ((t) | (v) << 8) 122 123 struct zs_chanstate { 124 struct zs_chanstate *cs_next; /* linked list for zshard() */ 125 volatile struct zschan *cs_zc; /* points to hardware regs */ 126 int cs_unit; /* unit number */ 127 struct tty *cs_ttyp; /* ### */ 128 129 /* 130 * We must keep a copy of the write registers as they are 131 * mostly write-only and we sometimes need to set and clear 132 * individual bits (e.g., in WR3). Not all of these are 133 * needed but 16 bytes is cheap and this makes the addressing 134 * simpler. Unfortunately, we can only write to some registers 135 * when the chip is not actually transmitting, so whenever 136 * we are expecting a `transmit done' interrupt the preg array 137 * is allowed to `get ahead' of the current values. In a 138 * few places we must change the current value of a register, 139 * rather than (or in addition to) the pending value; for these 140 * cs_creg[] contains the current value. 141 */ 142 u_char cs_creg[16]; /* current values */ 143 u_char cs_preg[16]; /* pending values */ 144 u_char cs_heldchange; /* change pending (creg != preg) */ 145 u_char cs_rr0; /* last rr0 processed */ 146 147 /* pure software data, per channel */ 148 char cs_softcar; /* software carrier */ 149 char cs_xxx; /* (spare) */ 150 151 /* 152 * The transmit byte count and address are used for pseudo-DMA 153 * output in the hardware interrupt code. PDMA can be suspended 154 * to get pending changes done; heldtbc is used for this. It can 155 * also be stopped for ^S; this sets TS_TTSTOP in tp->t_state. 156 */ 157 int cs_tbc; /* transmit byte count */ 158 caddr_t cs_tba; /* transmit buffer address */ 159 int cs_heldtbc; /* held tbc while xmission stopped */ 160 161 /* 162 * Printing an overrun error message often takes long enough to 163 * cause another overrun, so we only print one per second. 164 */ 165 long cs_rotime; /* time of last ring overrun */ 166 long cs_fotime; /* time of last fifo overrun */ 167 168 /* 169 * The ring buffer. 170 */ 171 u_int cs_rbget; /* ring buffer `get' index */ 172 volatile u_int cs_rbput; /* ring buffer `put' index */ 173 int *cs_rbuf; /* type, value pairs */ 174 }; 175 176 #define ZS_CHAN_A 0 177 #define ZS_CHAN_B 1 178 179 /* 180 * Macros to read and write individual registers (except 0) in a channel. 181 */ 182 #define ZS_READ(c, r) ((c)->zc_csr = (r), (c)->zc_csr) 183 #define ZS_WRITE(c, r, v) ((c)->zc_csr = (r), (c)->zc_csr = (v)) 184 185 /* 186 * Split minor into unit, dialin/dialout & flag nibble. 187 */ 188 #define ZS_UNIT(dev) ((minor(dev) >> 4) & 0xf) 189 #define ZS_FLAGS(dev) (minor(dev) & 0xf) 190 #define ZS_DIALOUT(dev) (minor(dev) & 0x80000) 191