1 /* $NetBSD: zs_kgdb.c,v 1.7 2007/10/17 19:55:20 garbled 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/cdefs.h> 51 __KERNEL_RCSID(0, "$NetBSD: zs_kgdb.c,v 1.7 2007/10/17 19:55:20 garbled Exp $"); 52 53 #include <sys/param.h> 54 #include <sys/systm.h> 55 #include <sys/proc.h> 56 #include <sys/device.h> 57 #include <sys/conf.h> 58 #include <sys/ioctl.h> 59 #include <sys/kernel.h> 60 #include <sys/syslog.h> 61 #include <sys/kgdb.h> 62 63 #include <dev/ofw/openfirm.h> 64 #include <dev/ic/z8530reg.h> 65 #include <machine/z8530var.h> 66 67 static void zs_setparam __P((struct zs_chanstate *, int, int)); 68 static void zskgdb __P((struct zs_chanstate *)); 69 70 struct zsops zsops_kgdb; 71 72 static u_char zs_kgdb_regs[16] = { 73 0, /* 0: CMD (reset, etc.) */ 74 0, /* 1: ~(ZSWR1_RIE | ZSWR1_TIE | ZSWR1_SIE) */ 75 0, /* IVECT */ 76 ZSWR3_RX_8 | ZSWR3_RX_ENABLE, 77 ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP, 78 ZSWR5_TX_8 | ZSWR5_TX_ENABLE, 79 0, /* 6: TXSYNC/SYNCLO */ 80 0, /* 7: RXSYNC/SYNCHI */ 81 0, /* 8: alias for data port */ 82 ZSWR9_MASTER_IE, 83 0, /*10: Misc. TX/RX control bits */ 84 ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD, 85 ((PCLK/32)/38400)-2, /*12: BAUDLO (default=38400) */ 86 0, /*13: BAUDHI (default=38400) */ 87 ZSWR14_BAUD_ENA, 88 ZSWR15_BREAK_IE, 89 }; 90 91 /* 92 * This replaces "zs_reset()" in the sparc driver. 93 */ 94 static void 95 zs_setparam(cs, iena, rate) 96 struct zs_chanstate *cs; 97 int iena; 98 int rate; 99 { 100 int s, tconst; 101 102 bcopy(zs_kgdb_regs, cs->cs_preg, 16); 103 104 if (iena) { 105 cs->cs_preg[1] = ZSWR1_RIE | ZSWR1_SIE; 106 } 107 108 /* Initialize the speed, etc. */ 109 tconst = BPS_TO_TCONST(cs->cs_brg_clk, rate); 110 cs->cs_preg[5] |= ZSWR5_DTR | ZSWR5_RTS; 111 cs->cs_preg[12] = tconst; 112 cs->cs_preg[13] = tconst >> 8; 113 114 s = splhigh(); 115 zs_loadchannelregs(cs); 116 splx(s); 117 } 118 119 #ifndef KGDB_DEVNAME 120 #define KGDB_DEVNAME "scca" 121 #endif 122 char *zs_kgdb_devname = KGDB_DEVNAME; 123 /* 124 * Set up for kgdb; called at boot time before configuration. 125 * KGDB interrupts will be enabled later when zs0 is configured. 126 * Called after cninit(), so printf() etc. works. 127 */ 128 void 129 zs_kgdb_init() 130 { 131 extern const struct cdevsw zstty_cdevsw; 132 struct zs_chanstate cs; 133 volatile struct zschan *zc; 134 int escc, escc_ch, obio, zs_offset; 135 int channel = 0; 136 u_int32_t reg[5]; 137 char name[16]; 138 139 if ((escc_ch = OF_finddevice(zs_kgdb_devname)) == -1) 140 return; 141 142 memset(name, 0, sizeof(name)); 143 if (OF_getprop(escc_ch, "device_type", name, sizeof(name)) == -1) 144 return; 145 146 if (strcmp(name, "serial") != 0) 147 return; 148 149 memset(name, 0, sizeof(name)); 150 if (OF_getprop(escc_ch, "name", name, sizeof(name)) == -1) 151 return; 152 153 if (strcmp(name, "ch-b") == 0) 154 channel = 1; 155 156 if (OF_getprop(escc_ch, "reg", reg, sizeof(reg)) < 4) 157 return; 158 zs_offset = reg[0]; 159 160 escc = OF_parent(escc_ch); 161 obio = OF_parent(escc); 162 163 if (OF_getprop(obio, "assigned-addresses", reg, sizeof(reg)) < 12) 164 return; 165 zc = (struct zschan *)(reg[2] + zs_offset); 166 167 kgdb_dev = makedev(cdevsw_lookup_major(&zstty_cdevsw), channel); 168 169 printf("zs_kgdb_init: attaching tty%02d at %d baud\n", 170 channel, kgdb_rate); 171 172 /* Setup temporary chanstate. */ 173 bzero((void *)&cs, sizeof(cs)); 174 cs.cs_channel = channel; 175 cs.cs_brg_clk = PCLK / 16; 176 cs.cs_reg_csr = &zc->zc_csr; 177 cs.cs_reg_data = &zc->zc_data; 178 179 /* Now set parameters. (interrupts disabled) */ 180 zs_setparam(&cs, 0, kgdb_rate); 181 182 /* Store the getc/putc functions and arg. */ 183 kgdb_attach(zs_getc, zs_putc, __UNVOLATILE(zc)); 184 } 185 186 /* 187 * This is a "hook" called by zstty_attach to allow the tty 188 * to be "taken over" for exclusive use by kgdb. 189 * Return non-zero if this is the kgdb port. 190 * 191 * Set the speed to kgdb_rate, CS8, etc. 192 */ 193 int 194 zs_check_kgdb(cs, dev) 195 struct zs_chanstate *cs; 196 int dev; 197 { 198 199 if (dev != kgdb_dev) 200 return (0); 201 202 /* 203 * Yes, this is port in use by kgdb. 204 */ 205 cs->cs_private = NULL; 206 cs->cs_ops = &zsops_kgdb; 207 208 /* Now set parameters. (interrupts enabled) */ 209 zs_setparam(cs, 1, kgdb_rate); 210 211 return (1); 212 } 213 214 /* 215 * KGDB framing character received: enter kernel debugger. This probably 216 * should time out after a few seconds to avoid hanging on spurious input. 217 */ 218 static void 219 zskgdb(cs) 220 struct zs_chanstate *cs; 221 { 222 int unit = minor(kgdb_dev); 223 224 printf("zstty%d: kgdb interrupt\n", unit); 225 /* This will trap into the debugger. */ 226 kgdb_connect(1); 227 } 228 229 230 /**************************************************************** 231 * Interface to the lower layer (zscc) 232 ****************************************************************/ 233 234 static void zs_kgdb_rxint __P((struct zs_chanstate *)); 235 static void zs_kgdb_stint __P((struct zs_chanstate *, int)); 236 static void zs_kgdb_txint __P((struct zs_chanstate *)); 237 static void zs_kgdb_softint __P((struct zs_chanstate *)); 238 239 int kgdb_input_lost; 240 241 static void 242 zs_kgdb_rxint(cs) 243 struct zs_chanstate *cs; 244 { 245 register u_char c, rr1; 246 247 /* 248 * First read the status, because reading the received char 249 * destroys the status of this char. 250 */ 251 rr1 = zs_read_reg(cs, 1); 252 c = zs_read_data(cs); 253 254 if (rr1 & (ZSRR1_FE | ZSRR1_DO | ZSRR1_PE)) { 255 /* Clear the receive error. */ 256 zs_write_csr(cs, ZSWR0_RESET_ERRORS); 257 } 258 259 if (c == KGDB_START) { 260 zskgdb(cs); 261 } else { 262 kgdb_input_lost++; 263 } 264 } 265 266 static void 267 zs_kgdb_txint(cs) 268 register struct zs_chanstate *cs; 269 { 270 register int rr0; 271 272 rr0 = zs_read_csr(cs); 273 zs_write_csr(cs, ZSWR0_RESET_TXINT); 274 } 275 276 static void 277 zs_kgdb_stint(cs, force) 278 register struct zs_chanstate *cs; 279 int force; 280 { 281 register int rr0; 282 283 rr0 = zs_read_csr(cs); 284 zs_write_csr(cs, ZSWR0_RESET_STATUS); 285 286 /* 287 * Check here for console break, so that we can abort 288 * even when interrupts are locking up the machine. 289 */ 290 if (rr0 & ZSRR0_BREAK) { 291 zskgdb(cs); 292 } 293 } 294 295 static void 296 zs_kgdb_softint(cs) 297 struct zs_chanstate *cs; 298 { 299 printf("zs_kgdb_softint?\n"); 300 } 301 302 struct zsops zsops_kgdb = { 303 zs_kgdb_rxint, /* receive char available */ 304 zs_kgdb_stint, /* external/status */ 305 zs_kgdb_txint, /* xmit buffer empty */ 306 zs_kgdb_softint, /* process software interrupt */ 307 }; 308