1 /* $NetBSD: zs_kgdb.c,v 1.3 2002/09/06 13:18:43 gehenna 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 extern const struct cdevsw zstty_cdevsw; 140 141 if (cdevsw_lookup(kgdb_dev) != &zstty_cdevsw) 142 return; 143 144 unit = (kgdb_dev & 2) ? 2 : 0; 145 channel = kgdb_dev & 1; 146 printf("zs_kgdb_init: attaching serial%d at %d baud\n", 147 (kgdb_dev & 3), kgdb_rate); 148 149 zc = zs_get_chan_addr(unit, channel); 150 151 /* Attach KGDB comms functions to this device */ 152 kgdb_attach(zs_getc, zs_putc, (void *)zc); 153 } 154 155 /* 156 * This is a "hook" called by the MI zstty_attach driver 157 * to allow the tty to be "taken over" for exclusive use by kgdb. 158 * Return non-zero if this is the kgdb port. 159 * 160 * Set the speed to kgdb_rate, CS8, etc. 161 */ 162 int 163 zs_check_kgdb(cs, dev) 164 struct zs_chanstate *cs; 165 int dev; 166 { 167 168 if (dev != kgdb_dev) 169 return (0); 170 171 /* 172 * Yes, this is port in use by kgdb. 173 */ 174 cs->cs_private = NULL; 175 cs->cs_ops = &zsops_kgdb; 176 177 /* Now set parameters. (interrupts enabled) */ 178 zs_setparam(cs, 1, kgdb_rate); 179 180 return (1); 181 } 182 183 /* 184 * KGDB framing character received: enter kernel debugger. This probably 185 * should time out after a few seconds to avoid hanging on spurious input. 186 */ 187 void 188 zskgdb(cs) 189 struct zs_chanstate *cs; 190 { 191 int unit = minor(kgdb_dev); 192 193 printf("zstty%d: kgdb interrupt\n", unit); 194 /* This will trap into the debugger. */ 195 kgdb_connect(1); 196 } 197 198 199 /**************************************************************** 200 * Interface to the lower layer (zscc) 201 ****************************************************************/ 202 203 static void zs_kgdb_rxint __P((struct zs_chanstate *)); 204 static void zs_kgdb_stint __P((struct zs_chanstate *, int)); 205 static void zs_kgdb_txint __P((struct zs_chanstate *)); 206 static void zs_kgdb_softint __P((struct zs_chanstate *)); 207 208 static struct zsops zsops_kgdb = { 209 zs_kgdb_rxint, /* receive char available */ 210 zs_kgdb_stint, /* external/status */ 211 zs_kgdb_txint, /* xmit buffer empty */ 212 zs_kgdb_softint, /* process software interrupt */ 213 }; 214 215 int kgdb_input_lost; 216 217 static void 218 zs_kgdb_rxint(cs) 219 struct zs_chanstate *cs; 220 { 221 register u_char c, rr1; 222 223 /* 224 * First read the status, because reading the received char 225 * destroys the status of this char. 226 */ 227 rr1 = zs_read_reg(cs, 1); 228 c = zs_read_data(cs); 229 230 if (rr1 & (ZSRR1_FE | ZSRR1_DO | ZSRR1_PE)) { 231 /* Clear the receive error. */ 232 zs_write_csr(cs, ZSWR0_RESET_ERRORS); 233 } 234 235 if (c == KGDB_START) { 236 zskgdb(cs); 237 } else { 238 kgdb_input_lost++; 239 } 240 } 241 242 static void 243 zs_kgdb_txint(cs) 244 register struct zs_chanstate *cs; 245 { 246 register int rr0; 247 248 rr0 = zs_read_csr(cs); 249 zs_write_csr(cs, ZSWR0_RESET_TXINT); 250 } 251 252 static void 253 zs_kgdb_stint(cs, force) 254 register struct zs_chanstate *cs; 255 int force; 256 { 257 register int rr0; 258 259 rr0 = zs_read_csr(cs); 260 zs_write_csr(cs, ZSWR0_RESET_STATUS); 261 262 /* 263 * Check here for console break, so that we can abort 264 * even when interrupts are locking up the machine. 265 */ 266 if (rr0 & ZSRR0_BREAK) { 267 zskgdb(cs); 268 } 269 } 270 271 static void 272 zs_kgdb_softint(cs) 273 struct zs_chanstate *cs; 274 { 275 printf("zs_kgdb_softint?\n"); 276 } 277 278 279