1 /* $NetBSD: zs_kgdb.c,v 1.1 2002/01/06 00:36:38 dbj 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 struct zs_chanstate cs; 129 volatile struct zschan *zc; 130 int escc, escc_ch, obio, zs_offset; 131 int channel = 0; 132 u_int32_t reg[5]; 133 char name[16]; 134 135 if ((escc_ch = OF_finddevice(zs_kgdb_devname)) == -1) 136 return; 137 138 memset(name, 0, sizeof(name)); 139 if (OF_getprop(escc_ch, "device_type", name, sizeof(name)) == -1) 140 return; 141 142 if (strcmp(name, "serial") != 0) 143 return; 144 145 memset(name, 0, sizeof(name)); 146 if (OF_getprop(escc_ch, "name", name, sizeof(name)) == -1) 147 return; 148 149 if (strcmp(name, "ch-b") == 0) 150 channel = 1; 151 152 if (OF_getprop(escc_ch, "reg", reg, sizeof(reg)) < 4) 153 return; 154 zs_offset = reg[0]; 155 156 escc = OF_parent(escc_ch); 157 obio = OF_parent(escc); 158 159 if (OF_getprop(obio, "assigned-addresses", reg, sizeof(reg)) < 12) 160 return; 161 zc = (struct zschan *)(reg[2] + zs_offset); 162 163 kgdb_dev = makedev(zs_major, channel); 164 165 printf("zs_kgdb_init: attaching tty%02d at %d baud\n", 166 channel, kgdb_rate); 167 168 /* Setup temporary chanstate. */ 169 bzero((caddr_t)&cs, sizeof(cs)); 170 cs.cs_channel = channel; 171 cs.cs_brg_clk = PCLK / 16; 172 cs.cs_reg_csr = &zc->zc_csr; 173 cs.cs_reg_data = &zc->zc_data; 174 175 /* Now set parameters. (interrupts disabled) */ 176 zs_setparam(&cs, 0, kgdb_rate); 177 178 /* Store the getc/putc functions and arg. */ 179 kgdb_attach(zs_getc, zs_putc, (void *)zc); 180 } 181 182 /* 183 * This is a "hook" called by zstty_attach to allow the tty 184 * to be "taken over" for exclusive use by kgdb. 185 * Return non-zero if this is the kgdb port. 186 * 187 * Set the speed to kgdb_rate, CS8, etc. 188 */ 189 int 190 zs_check_kgdb(cs, dev) 191 struct zs_chanstate *cs; 192 int dev; 193 { 194 195 if (dev != kgdb_dev) 196 return (0); 197 198 /* 199 * Yes, this is port in use by kgdb. 200 */ 201 cs->cs_private = NULL; 202 cs->cs_ops = &zsops_kgdb; 203 204 /* Now set parameters. (interrupts enabled) */ 205 zs_setparam(cs, 1, kgdb_rate); 206 207 return (1); 208 } 209 210 /* 211 * KGDB framing character received: enter kernel debugger. This probably 212 * should time out after a few seconds to avoid hanging on spurious input. 213 */ 214 static void 215 zskgdb(cs) 216 struct zs_chanstate *cs; 217 { 218 int unit = minor(kgdb_dev); 219 220 printf("zstty%d: kgdb interrupt\n", unit); 221 /* This will trap into the debugger. */ 222 kgdb_connect(1); 223 } 224 225 226 /**************************************************************** 227 * Interface to the lower layer (zscc) 228 ****************************************************************/ 229 230 static void zs_kgdb_rxint __P((struct zs_chanstate *)); 231 static void zs_kgdb_stint __P((struct zs_chanstate *, int)); 232 static void zs_kgdb_txint __P((struct zs_chanstate *)); 233 static void zs_kgdb_softint __P((struct zs_chanstate *)); 234 235 int kgdb_input_lost; 236 237 static void 238 zs_kgdb_rxint(cs) 239 struct zs_chanstate *cs; 240 { 241 register u_char c, rr1; 242 243 /* 244 * First read the status, because reading the received char 245 * destroys the status of this char. 246 */ 247 rr1 = zs_read_reg(cs, 1); 248 c = zs_read_data(cs); 249 250 if (rr1 & (ZSRR1_FE | ZSRR1_DO | ZSRR1_PE)) { 251 /* Clear the receive error. */ 252 zs_write_csr(cs, ZSWR0_RESET_ERRORS); 253 } 254 255 if (c == KGDB_START) { 256 zskgdb(cs); 257 } else { 258 kgdb_input_lost++; 259 } 260 } 261 262 static void 263 zs_kgdb_txint(cs) 264 register struct zs_chanstate *cs; 265 { 266 register int rr0; 267 268 rr0 = zs_read_csr(cs); 269 zs_write_csr(cs, ZSWR0_RESET_TXINT); 270 } 271 272 static void 273 zs_kgdb_stint(cs, force) 274 register struct zs_chanstate *cs; 275 int force; 276 { 277 register int rr0; 278 279 rr0 = zs_read_csr(cs); 280 zs_write_csr(cs, ZSWR0_RESET_STATUS); 281 282 /* 283 * Check here for console break, so that we can abort 284 * even when interrupts are locking up the machine. 285 */ 286 if (rr0 & ZSRR0_BREAK) { 287 zskgdb(cs); 288 } 289 } 290 291 static void 292 zs_kgdb_softint(cs) 293 struct zs_chanstate *cs; 294 { 295 printf("zs_kgdb_softint?\n"); 296 } 297 298 struct zsops zsops_kgdb = { 299 zs_kgdb_rxint, /* receive char available */ 300 zs_kgdb_stint, /* external/status */ 301 zs_kgdb_txint, /* xmit buffer empty */ 302 zs_kgdb_softint, /* process software interrupt */ 303 }; 304