1 /* $NetBSD: zs_kgdb.c,v 1.1 2002/03/22 00:23:54 fredette 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. 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 "opt_kgdb.h" 51 52 #include <sys/param.h> 53 #include <sys/systm.h> 54 #include <sys/proc.h> 55 #include <sys/device.h> 56 #include <sys/conf.h> 57 #include <sys/ioctl.h> 58 #include <sys/kernel.h> 59 #include <sys/syslog.h> 60 #include <sys/kgdb.h> 61 62 #include <dev/ic/z8530reg.h> 63 #include <machine/z8530var.h> 64 #include <machine/promlib.h> 65 #include <sun2/dev/cons.h> 66 67 static void zs_setparam __P((struct zs_chanstate *, int, int)); 68 struct zsops zsops_kgdb; 69 70 extern int zs_getc __P((void *arg)); 71 extern void zs_putc __P((void *arg, int c)); 72 73 static u_char zs_kgdb_regs[16] = { 74 0, /* 0: CMD (reset, etc.) */ 75 0, /* 1: No interrupts yet. */ 76 #ifdef ZS_INIT_IVECT 77 ZS_INIT_IVECT, /* 2: IVECT */ 78 #else 79 0, /* 2: IVECT */ 80 #endif 81 ZSWR3_RX_8 | ZSWR3_RX_ENABLE, 82 ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP, 83 ZSWR5_TX_8 | ZSWR5_TX_ENABLE, 84 0, /* 6: TXSYNC/SYNCLO */ 85 0, /* 7: RXSYNC/SYNCHI */ 86 0, /* 8: alias for data port */ 87 #ifdef ZS_INIT_IVECT 88 ZSWR9_MASTER_IE, 89 #else 90 ZSWR9_MASTER_IE | ZSWR9_NO_VECTOR, 91 #endif 92 0, /*10: Misc. TX/RX control bits */ 93 ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD, 94 14, /*12: BAUDLO (default=9600) */ 95 0, /*13: BAUDHI (default=9600) */ 96 ZSWR14_BAUD_ENA | ZSWR14_BAUD_FROM_PCLK, 97 ZSWR15_BREAK_IE, 98 }; 99 100 /* 101 * This replaces "zs_reset()" in the sparc driver. 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 bcopy(zs_kgdb_regs, cs->cs_preg, 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 cs->cs_preg[5] |= ZSWR5_DTR | ZSWR5_RTS; 120 cs->cs_preg[12] = tconst; 121 cs->cs_preg[13] = tconst >> 8; 122 123 s = splhigh(); 124 zs_loadchannelregs(cs); 125 splx(s); 126 } 127 128 /* 129 * Set up for kgdb; called at boot time before configuration. 130 * KGDB interrupts will be enabled later when zs0 is configured. 131 * Called after cninit(), so printf() etc. works. 132 */ 133 void 134 zs_kgdb_init() 135 { 136 struct zs_chanstate cs; 137 struct zsdevice *zsd; 138 volatile struct zschan *zc; 139 int channel, promzs_unit; 140 141 /* printf("zs_kgdb_init: kgdb_dev=0x%x\n", kgdb_dev); */ 142 if (major(kgdb_dev) != zs_major) 143 return; 144 145 /* Note: (ttya,ttyb) on zs0, and (ttyc,ttyd) on zs2 */ 146 promzs_unit = (kgdb_dev & 2) ? 2 : 0; 147 channel = kgdb_dev & 1; 148 printf("zs_kgdb_init: attaching tty%c at %d baud\n", 149 'a' + (kgdb_dev & 3), kgdb_rate); 150 151 /* Setup temporary chanstate. */ 152 bzero((caddr_t)&cs, sizeof(cs)); 153 zsd = zs_find_prom(promzs_unit); 154 if (zsd == NULL) { 155 printf("zs_kgdb_init: zs not mapped.\n"); 156 return; 157 } 158 zc = (channel == 0) ? &zsd->zs_chan_a : &zsd->zs_chan_b; 159 160 cs.cs_channel = channel; 161 cs.cs_brg_clk = PCLK / 16; 162 cs.cs_reg_csr = &zc->zc_csr; 163 cs.cs_reg_data = &zc->zc_data; 164 165 /* Now set parameters. (interrupts disabled) */ 166 zs_setparam(&cs, 0, kgdb_rate); 167 168 /* Store the getc/putc functions and arg. */ 169 kgdb_attach(zs_getc, zs_putc, (void *)zc); 170 } 171 172 /* 173 * This is a "hook" called by zstty_attach to allow the tty 174 * to be "taken over" for exclusive use by kgdb. 175 * Return non-zero if this is the kgdb port. 176 * 177 * Set the speed to kgdb_rate, CS8, etc. 178 */ 179 int 180 zs_check_kgdb(cs, dev) 181 struct zs_chanstate *cs; 182 int dev; 183 { 184 185 if (dev != kgdb_dev) 186 return (0); 187 188 /* 189 * Yes, this is port in use by kgdb. 190 */ 191 cs->cs_private = NULL; 192 cs->cs_ops = &zsops_kgdb; 193 194 /* Now set parameters. (interrupts enabled) */ 195 zs_setparam(cs, 1, kgdb_rate); 196 197 return (1); 198 } 199 200 /* 201 * KGDB framing character received: enter kernel debugger. This probably 202 * should time out after a few seconds to avoid hanging on spurious input. 203 */ 204 void 205 zskgdb(cs) 206 struct zs_chanstate *cs; 207 { 208 int unit = minor(kgdb_dev); 209 210 printf("zstty%d: kgdb interrupt\n", unit); 211 /* This will trap into the debugger. */ 212 kgdb_connect(1); 213 } 214 215 216 /**************************************************************** 217 * Interface to the lower layer (zscc) 218 ****************************************************************/ 219 220 static void zs_kgdb_rxint __P((struct zs_chanstate *)); 221 static void zs_kgdb_stint __P((struct zs_chanstate *, int)); 222 static void zs_kgdb_txint __P((struct zs_chanstate *)); 223 static void zs_kgdb_softint __P((struct zs_chanstate *)); 224 225 int kgdb_input_lost; 226 227 static void 228 zs_kgdb_rxint(cs) 229 struct zs_chanstate *cs; 230 { 231 register u_char c, rr1; 232 233 /* 234 * First read the status, because reading the received char 235 * destroys the status of this char. 236 */ 237 rr1 = zs_read_reg(cs, 1); 238 c = zs_read_data(cs); 239 240 if (rr1 & (ZSRR1_FE | ZSRR1_DO | ZSRR1_PE)) { 241 /* Clear the receive error. */ 242 zs_write_csr(cs, ZSWR0_RESET_ERRORS); 243 } 244 245 if (c == KGDB_START) { 246 zskgdb(cs); 247 } else { 248 kgdb_input_lost++; 249 } 250 } 251 252 static void 253 zs_kgdb_txint(cs) 254 register struct zs_chanstate *cs; 255 { 256 register int rr0; 257 258 rr0 = zs_read_csr(cs); 259 zs_write_csr(cs, ZSWR0_RESET_TXINT); 260 } 261 262 static void 263 zs_kgdb_stint(cs, force) 264 register struct zs_chanstate *cs; 265 int force; 266 { 267 register int rr0; 268 269 rr0 = zs_read_csr(cs); 270 zs_write_csr(cs, ZSWR0_RESET_STATUS); 271 272 /* 273 * Check here for console break, so that we can abort 274 * even when interrupts are locking up the machine. 275 */ 276 if (rr0 & ZSRR0_BREAK) { 277 zskgdb(cs); 278 } 279 } 280 281 static void 282 zs_kgdb_softint(cs) 283 struct zs_chanstate *cs; 284 { 285 printf("zs_kgdb_softint?\n"); 286 } 287 288 struct zsops zsops_kgdb = { 289 zs_kgdb_rxint, /* receive char available */ 290 zs_kgdb_stint, /* external/status */ 291 zs_kgdb_txint, /* xmit buffer empty */ 292 zs_kgdb_softint, /* process software interrupt */ 293 }; 294