1 /* $NetBSD: zs_kgdb.c,v 1.2 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. 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/ofw/openfirm.h> 61 #include <dev/ic/z8530reg.h> 62 #include <machine/z8530var.h> 63 64 static void zs_setparam __P((struct zs_chanstate *, int, int)); 65 static void zskgdb __P((struct zs_chanstate *)); 66 67 struct zsops zsops_kgdb; 68 69 static u_char zs_kgdb_regs[16] = { 70 0, /* 0: CMD (reset, etc.) */ 71 0, /* 1: ~(ZSWR1_RIE | ZSWR1_TIE | ZSWR1_SIE) */ 72 0, /* IVECT */ 73 ZSWR3_RX_8 | ZSWR3_RX_ENABLE, 74 ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP, 75 ZSWR5_TX_8 | ZSWR5_TX_ENABLE, 76 0, /* 6: TXSYNC/SYNCLO */ 77 0, /* 7: RXSYNC/SYNCHI */ 78 0, /* 8: alias for data port */ 79 ZSWR9_MASTER_IE, 80 0, /*10: Misc. TX/RX control bits */ 81 ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD, 82 ((PCLK/32)/38400)-2, /*12: BAUDLO (default=38400) */ 83 0, /*13: BAUDHI (default=38400) */ 84 ZSWR14_BAUD_ENA, 85 ZSWR15_BREAK_IE, 86 }; 87 88 /* 89 * This replaces "zs_reset()" in the sparc driver. 90 */ 91 static void 92 zs_setparam(cs, iena, rate) 93 struct zs_chanstate *cs; 94 int iena; 95 int rate; 96 { 97 int s, tconst; 98 99 bcopy(zs_kgdb_regs, cs->cs_preg, 16); 100 101 if (iena) { 102 cs->cs_preg[1] = ZSWR1_RIE | ZSWR1_SIE; 103 } 104 105 /* Initialize the speed, etc. */ 106 tconst = BPS_TO_TCONST(cs->cs_brg_clk, rate); 107 cs->cs_preg[5] |= ZSWR5_DTR | ZSWR5_RTS; 108 cs->cs_preg[12] = tconst; 109 cs->cs_preg[13] = tconst >> 8; 110 111 s = splhigh(); 112 zs_loadchannelregs(cs); 113 splx(s); 114 } 115 116 #ifndef KGDB_DEVNAME 117 #define KGDB_DEVNAME "scca" 118 #endif 119 char *zs_kgdb_devname = KGDB_DEVNAME; 120 /* 121 * Set up for kgdb; called at boot time before configuration. 122 * KGDB interrupts will be enabled later when zs0 is configured. 123 * Called after cninit(), so printf() etc. works. 124 */ 125 void 126 zs_kgdb_init() 127 { 128 extern const struct cdevsw zstty_cdevsw; 129 struct zs_chanstate cs; 130 volatile struct zschan *zc; 131 int escc, escc_ch, obio, zs_offset; 132 int channel = 0; 133 u_int32_t reg[5]; 134 char name[16]; 135 136 if ((escc_ch = OF_finddevice(zs_kgdb_devname)) == -1) 137 return; 138 139 memset(name, 0, sizeof(name)); 140 if (OF_getprop(escc_ch, "device_type", name, sizeof(name)) == -1) 141 return; 142 143 if (strcmp(name, "serial") != 0) 144 return; 145 146 memset(name, 0, sizeof(name)); 147 if (OF_getprop(escc_ch, "name", name, sizeof(name)) == -1) 148 return; 149 150 if (strcmp(name, "ch-b") == 0) 151 channel = 1; 152 153 if (OF_getprop(escc_ch, "reg", reg, sizeof(reg)) < 4) 154 return; 155 zs_offset = reg[0]; 156 157 escc = OF_parent(escc_ch); 158 obio = OF_parent(escc); 159 160 if (OF_getprop(obio, "assigned-addresses", reg, sizeof(reg)) < 12) 161 return; 162 zc = (struct zschan *)(reg[2] + zs_offset); 163 164 kgdb_dev = makedev(cdevsw_lookup_major(&zstty_cdevsw), channel); 165 166 printf("zs_kgdb_init: attaching tty%02d at %d baud\n", 167 channel, kgdb_rate); 168 169 /* Setup temporary chanstate. */ 170 bzero((caddr_t)&cs, sizeof(cs)); 171 cs.cs_channel = channel; 172 cs.cs_brg_clk = PCLK / 16; 173 cs.cs_reg_csr = &zc->zc_csr; 174 cs.cs_reg_data = &zc->zc_data; 175 176 /* Now set parameters. (interrupts disabled) */ 177 zs_setparam(&cs, 0, kgdb_rate); 178 179 /* Store the getc/putc functions and arg. */ 180 kgdb_attach(zs_getc, zs_putc, (void *)zc); 181 } 182 183 /* 184 * This is a "hook" called by zstty_attach to allow the tty 185 * to be "taken over" for exclusive use by kgdb. 186 * Return non-zero if this is the kgdb port. 187 * 188 * Set the speed to kgdb_rate, CS8, etc. 189 */ 190 int 191 zs_check_kgdb(cs, dev) 192 struct zs_chanstate *cs; 193 int dev; 194 { 195 196 if (dev != kgdb_dev) 197 return (0); 198 199 /* 200 * Yes, this is port in use by kgdb. 201 */ 202 cs->cs_private = NULL; 203 cs->cs_ops = &zsops_kgdb; 204 205 /* Now set parameters. (interrupts enabled) */ 206 zs_setparam(cs, 1, kgdb_rate); 207 208 return (1); 209 } 210 211 /* 212 * KGDB framing character received: enter kernel debugger. This probably 213 * should time out after a few seconds to avoid hanging on spurious input. 214 */ 215 static void 216 zskgdb(cs) 217 struct zs_chanstate *cs; 218 { 219 int unit = minor(kgdb_dev); 220 221 printf("zstty%d: kgdb interrupt\n", unit); 222 /* This will trap into the debugger. */ 223 kgdb_connect(1); 224 } 225 226 227 /**************************************************************** 228 * Interface to the lower layer (zscc) 229 ****************************************************************/ 230 231 static void zs_kgdb_rxint __P((struct zs_chanstate *)); 232 static void zs_kgdb_stint __P((struct zs_chanstate *, int)); 233 static void zs_kgdb_txint __P((struct zs_chanstate *)); 234 static void zs_kgdb_softint __P((struct zs_chanstate *)); 235 236 int kgdb_input_lost; 237 238 static void 239 zs_kgdb_rxint(cs) 240 struct zs_chanstate *cs; 241 { 242 register u_char c, rr1; 243 244 /* 245 * First read the status, because reading the received char 246 * destroys the status of this char. 247 */ 248 rr1 = zs_read_reg(cs, 1); 249 c = zs_read_data(cs); 250 251 if (rr1 & (ZSRR1_FE | ZSRR1_DO | ZSRR1_PE)) { 252 /* Clear the receive error. */ 253 zs_write_csr(cs, ZSWR0_RESET_ERRORS); 254 } 255 256 if (c == KGDB_START) { 257 zskgdb(cs); 258 } else { 259 kgdb_input_lost++; 260 } 261 } 262 263 static void 264 zs_kgdb_txint(cs) 265 register struct zs_chanstate *cs; 266 { 267 register int rr0; 268 269 rr0 = zs_read_csr(cs); 270 zs_write_csr(cs, ZSWR0_RESET_TXINT); 271 } 272 273 static void 274 zs_kgdb_stint(cs, force) 275 register struct zs_chanstate *cs; 276 int force; 277 { 278 register int rr0; 279 280 rr0 = zs_read_csr(cs); 281 zs_write_csr(cs, ZSWR0_RESET_STATUS); 282 283 /* 284 * Check here for console break, so that we can abort 285 * even when interrupts are locking up the machine. 286 */ 287 if (rr0 & ZSRR0_BREAK) { 288 zskgdb(cs); 289 } 290 } 291 292 static void 293 zs_kgdb_softint(cs) 294 struct zs_chanstate *cs; 295 { 296 printf("zs_kgdb_softint?\n"); 297 } 298 299 struct zsops zsops_kgdb = { 300 zs_kgdb_rxint, /* receive char available */ 301 zs_kgdb_stint, /* external/status */ 302 zs_kgdb_txint, /* xmit buffer empty */ 303 zs_kgdb_softint, /* process software interrupt */ 304 }; 305