1 /* $NetBSD: zs_kgdb.c,v 1.2 2001/07/08 04:25:36 wdk Exp $ */ 2 3 /*- 4 * Copyright (c) 1996 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Gordon W. Ross and Wayne Knowles. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the NetBSD 21 * Foundation, Inc. and its contributors. 22 * 4. Neither the name of The NetBSD Foundation nor the names of its 23 * contributors may be used to endorse or promote products derived 24 * from this software without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 29 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 36 * POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39 /* 40 * Hooks for kgdb when attached via the z8530 driver 41 * 42 * To use this, build a kernel with: option KGDB, and 43 * boot that kernel with "-d". (The kernel will call 44 * zs_kgdb_init, kgdb_connect.) When the console prints 45 * "kgdb waiting..." you run "gdb -k kernel" and do: 46 * (gdb) set remotebaud 19200 47 * (gdb) target remote /dev/ttyb 48 */ 49 50 #include <sys/param.h> 51 #include <sys/systm.h> 52 #include <sys/proc.h> 53 #include <sys/device.h> 54 #include <sys/conf.h> 55 #include <sys/ioctl.h> 56 #include <sys/kernel.h> 57 #include <sys/syslog.h> 58 #include <sys/kgdb.h> 59 60 #include <dev/ic/z8530reg.h> 61 #include <machine/z8530var.h> 62 63 /* 64 * Hooks for kgdb when attached via the z8530 driver 65 * 66 * To use this, build a kernel with: option KGDB, and 67 * boot that kernel with "-d". (The kernel will call 68 * zs_kgdb_init, kgdb_connect.) When the console prints 69 * "kgdb waiting..." you run "gdb -k kernel" and do: 70 * (gdb) set remotebaud 19200 71 * (gdb) target remote /dev/ttyb 72 */ 73 74 void zs_kgdb_init __P((void)); 75 void zskgdb __P((struct zs_chanstate *cs)); 76 77 static void zs_setparam __P((struct zs_chanstate *, int, int)); 78 static struct zsops zsops_kgdb; 79 80 extern struct zschan *zs_get_chan_addr (int zs_unit, int channel); 81 extern int zs_getc __P((void *arg)); 82 extern void zs_putc __P((void *arg, int c)); 83 84 static u_char zs_kgdb_regs[16] = { 85 0, /* 0: CMD (reset, etc.) */ 86 0, /* 1: No interrupts yet. */ 87 0, /* 2: IVECT */ 88 ZSWR3_RX_8 | ZSWR3_RX_ENABLE, 89 ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP, 90 ZSWR5_TX_8 | ZSWR5_TX_ENABLE, 91 0, /* 6: TXSYNC/SYNCLO */ 92 0, /* 7: RXSYNC/SYNCHI */ 93 0, /* 8: alias for data port */ 94 ZSWR9_MASTER_IE | ZSWR9_NO_VECTOR, 95 0, /*10: Misc. TX/RX control bits */ 96 ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD, 97 14, /*12: BAUDLO (default=9600) */ 98 0, /*13: BAUDHI (default=9600) */ 99 ZSWR14_BAUD_ENA | ZSWR14_BAUD_FROM_PCLK, 100 ZSWR15_BREAK_IE, 101 }; 102 103 static void 104 zs_setparam(cs, iena, rate) 105 struct zs_chanstate *cs; 106 int iena; 107 int rate; 108 { 109 int s, tconst; 110 111 memcpy(cs->cs_preg, zs_kgdb_regs, 16); 112 113 if (iena) { 114 cs->cs_preg[1] = ZSWR1_RIE | ZSWR1_SIE; 115 } 116 117 /* Initialize the speed, etc. */ 118 tconst = BPS_TO_TCONST(cs->cs_brg_clk, rate); 119 120 cs->cs_preg[5] |= ZSWR5_DTR | ZSWR5_RTS; 121 cs->cs_preg[12] = tconst; 122 cs->cs_preg[13] = tconst >> 8; 123 124 s = splhigh(); 125 zs_loadchannelregs(cs); 126 splx(s); 127 } 128 129 /* 130 * Set up for kgdb; called at boot time before configuration. 131 * KGDB interrupts will be enabled later when zs0 is configured. 132 * Called after cninit(), so printf() etc. works. 133 */ 134 void 135 zs_kgdb_init() 136 { 137 volatile struct zschan *zc; 138 int channel, unit; 139 140 if (major(kgdb_dev) != zs_major) 141 return; 142 143 unit = (kgdb_dev & 2) ? 2 : 0; 144 channel = kgdb_dev & 1; 145 printf("zs_kgdb_init: attaching serial%d at %d baud\n", 146 (kgdb_dev & 3), kgdb_rate); 147 148 zc = zs_get_chan_addr(unit, channel); 149 150 /* Attach KGDB comms functions to this device */ 151 kgdb_attach(zs_getc, zs_putc, (void *)zc); 152 } 153 154 /* 155 * This is a "hook" called by the MI zstty_attach driver 156 * to allow the tty to be "taken over" for exclusive use by kgdb. 157 * Return non-zero if this is the kgdb port. 158 * 159 * Set the speed to kgdb_rate, CS8, etc. 160 */ 161 int 162 zs_check_kgdb(cs, dev) 163 struct zs_chanstate *cs; 164 int dev; 165 { 166 167 if (dev != kgdb_dev) 168 return (0); 169 170 /* 171 * Yes, this is port in use by kgdb. 172 */ 173 cs->cs_private = NULL; 174 cs->cs_ops = &zsops_kgdb; 175 176 /* Now set parameters. (interrupts enabled) */ 177 zs_setparam(cs, 1, kgdb_rate); 178 179 return (1); 180 } 181 182 /* 183 * KGDB framing character received: enter kernel debugger. This probably 184 * should time out after a few seconds to avoid hanging on spurious input. 185 */ 186 void 187 zskgdb(cs) 188 struct zs_chanstate *cs; 189 { 190 int unit = minor(kgdb_dev); 191 192 printf("zstty%d: kgdb interrupt\n", unit); 193 /* This will trap into the debugger. */ 194 kgdb_connect(1); 195 } 196 197 198 /**************************************************************** 199 * Interface to the lower layer (zscc) 200 ****************************************************************/ 201 202 static void zs_kgdb_rxint __P((struct zs_chanstate *)); 203 static void zs_kgdb_stint __P((struct zs_chanstate *, int)); 204 static void zs_kgdb_txint __P((struct zs_chanstate *)); 205 static void zs_kgdb_softint __P((struct zs_chanstate *)); 206 207 static struct zsops zsops_kgdb = { 208 zs_kgdb_rxint, /* receive char available */ 209 zs_kgdb_stint, /* external/status */ 210 zs_kgdb_txint, /* xmit buffer empty */ 211 zs_kgdb_softint, /* process software interrupt */ 212 }; 213 214 int kgdb_input_lost; 215 216 static void 217 zs_kgdb_rxint(cs) 218 struct zs_chanstate *cs; 219 { 220 register u_char c, rr1; 221 222 /* 223 * First read the status, because reading the received char 224 * destroys the status of this char. 225 */ 226 rr1 = zs_read_reg(cs, 1); 227 c = zs_read_data(cs); 228 229 if (rr1 & (ZSRR1_FE | ZSRR1_DO | ZSRR1_PE)) { 230 /* Clear the receive error. */ 231 zs_write_csr(cs, ZSWR0_RESET_ERRORS); 232 } 233 234 if (c == KGDB_START) { 235 zskgdb(cs); 236 } else { 237 kgdb_input_lost++; 238 } 239 } 240 241 static void 242 zs_kgdb_txint(cs) 243 register struct zs_chanstate *cs; 244 { 245 register int rr0; 246 247 rr0 = zs_read_csr(cs); 248 zs_write_csr(cs, ZSWR0_RESET_TXINT); 249 } 250 251 static void 252 zs_kgdb_stint(cs, force) 253 register struct zs_chanstate *cs; 254 int force; 255 { 256 register int rr0; 257 258 rr0 = zs_read_csr(cs); 259 zs_write_csr(cs, ZSWR0_RESET_STATUS); 260 261 /* 262 * Check here for console break, so that we can abort 263 * even when interrupts are locking up the machine. 264 */ 265 if (rr0 & ZSRR0_BREAK) { 266 zskgdb(cs); 267 } 268 } 269 270 static void 271 zs_kgdb_softint(cs) 272 struct zs_chanstate *cs; 273 { 274 printf("zs_kgdb_softint?\n"); 275 } 276 277 278