1 /* $NetBSD: zs_kgdb.c,v 1.17 2007/03/04 06:00:44 christos 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 1.17 2007/03/04 06:00:44 christos Exp $"); 52 53 #include "opt_kgdb.h" 54 55 #include <sys/param.h> 56 #include <sys/systm.h> 57 #include <sys/proc.h> 58 #include <sys/device.h> 59 #include <sys/conf.h> 60 #include <sys/ioctl.h> 61 #include <sys/kernel.h> 62 #include <sys/syslog.h> 63 #include <sys/kgdb.h> 64 65 #include <dev/ic/z8530reg.h> 66 #include <machine/z8530var.h> 67 #include <machine/autoconf.h> 68 #include <machine/promlib.h> 69 #include <sparc/dev/cons.h> 70 71 /* Suns provide a 4.9152 MHz clock to the ZS chips. */ 72 #define PCLK (9600 * 512) /* PCLK pin input clock rate */ 73 74 /* The layout of this is hardware-dependent (padding, order). */ 75 struct zschan { 76 volatile u_char zc_csr; /* ctrl,status, and indirect access */ 77 u_char zc_xxx0; 78 volatile u_char zc_data; /* data */ 79 u_char zc_xxx1; 80 }; 81 struct zsdevice { 82 /* Yes, they are backwards. */ 83 struct zschan zs_chan_b; 84 struct zschan zs_chan_a; 85 }; 86 87 static void zs_setparam(struct zs_chanstate *, int, int); 88 static void *findzs(int); 89 struct zsops zsops_kgdb; 90 91 extern int zs_getc(void *); 92 extern void zs_putc(void *, int); 93 94 static u_char zs_kgdb_regs[16] = { 95 0, /* 0: CMD (reset, etc.) */ 96 0, /* 1: No interrupts yet. */ 97 0, /* 2: IVECT */ 98 ZSWR3_RX_8 | ZSWR3_RX_ENABLE, 99 ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP, 100 ZSWR5_TX_8 | ZSWR5_TX_ENABLE, 101 0, /* 6: TXSYNC/SYNCLO */ 102 0, /* 7: RXSYNC/SYNCHI */ 103 0, /* 8: alias for data port */ 104 ZSWR9_MASTER_IE | ZSWR9_NO_VECTOR, 105 0, /*10: Misc. TX/RX control bits */ 106 ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD, 107 14, /*12: BAUDLO (default=9600) */ 108 0, /*13: BAUDHI (default=9600) */ 109 ZSWR14_BAUD_ENA | ZSWR14_BAUD_FROM_PCLK, 110 ZSWR15_BREAK_IE, 111 }; 112 113 /* 114 * This replaces "zs_reset()" in the sparc driver. 115 */ 116 static void 117 zs_setparam(struct zs_chanstate *cs, int iena, int rate) 118 { 119 int s, tconst; 120 121 bcopy(zs_kgdb_regs, cs->cs_preg, 16); 122 123 if (iena) { 124 cs->cs_preg[1] = ZSWR1_RIE | ZSWR1_SIE; 125 } 126 127 /* Initialize the speed, etc. */ 128 tconst = BPS_TO_TCONST(cs->cs_brg_clk, rate); 129 cs->cs_preg[5] |= ZSWR5_DTR | ZSWR5_RTS; 130 cs->cs_preg[12] = tconst; 131 cs->cs_preg[13] = tconst >> 8; 132 133 s = splhigh(); 134 zs_loadchannelregs(cs); 135 splx(s); 136 } 137 138 /* 139 * Set up for kgdb; called at boot time before configuration. 140 * KGDB interrupts will be enabled later when zs0 is configured. 141 * Called after cninit(), so printf() etc. works. 142 */ 143 void 144 zs_kgdb_init(void) 145 { 146 struct zs_chanstate cs; 147 struct zsdevice *zsd; 148 volatile struct zschan *zc; 149 int channel, promzs_unit; 150 extern const struct cdevsw zstty_cdevsw; 151 152 /* printf("zs_kgdb_init: kgdb_dev=0x%x\n", kgdb_dev); */ 153 if (cdevsw_lookup(kgdb_dev) != &zstty_cdevsw) 154 return; 155 156 /* Note: (ttya,ttyb) on zs0, and (ttyc,ttyd) on zs2 */ 157 promzs_unit = (kgdb_dev & 2) ? 2 : 0; 158 channel = kgdb_dev & 1; 159 printf("zs_kgdb_init: attaching tty%c at %d baud\n", 160 'a' + (kgdb_dev & 3), kgdb_rate); 161 162 /* Setup temporary chanstate. */ 163 bzero((void *)&cs, sizeof(cs)); 164 zsd = findzs(promzs_unit); 165 if (zsd == NULL) { 166 printf("zs_kgdb_init: zs not mapped.\n"); 167 return; 168 } 169 zc = (channel == 0) ? &zsd->zs_chan_a : &zsd->zs_chan_b; 170 171 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, __UNVOLATILE(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(struct zs_chanstate *cs, int dev) 192 { 193 194 if (dev != kgdb_dev) 195 return (0); 196 197 /* 198 * Yes, this is port in use by kgdb. 199 */ 200 cs->cs_private = NULL; 201 cs->cs_ops = &zsops_kgdb; 202 203 /* Now set parameters. (interrupts enabled) */ 204 zs_setparam(cs, 1, kgdb_rate); 205 206 return (1); 207 } 208 209 /* 210 * KGDB framing character received: enter kernel debugger. This probably 211 * should time out after a few seconds to avoid hanging on spurious input. 212 */ 213 void 214 zskgdb(struct zs_chanstate *cs) 215 { 216 int unit = minor(kgdb_dev); 217 218 printf("zstty%d: kgdb interrupt\n", unit); 219 /* This will trap into the debugger. */ 220 kgdb_connect(1); 221 } 222 223 224 /**************************************************************** 225 * Interface to the lower layer (zscc) 226 ****************************************************************/ 227 228 static void zs_kgdb_rxint(struct zs_chanstate *); 229 static void zs_kgdb_stint(struct zs_chanstate *, int); 230 static void zs_kgdb_txint(struct zs_chanstate *); 231 static void zs_kgdb_softint(struct zs_chanstate *); 232 233 int kgdb_input_lost; 234 235 static void 236 zs_kgdb_rxint(struct zs_chanstate *cs) 237 { 238 register u_char c, rr1; 239 240 /* 241 * First read the status, because reading the received char 242 * destroys the status of this char. 243 */ 244 rr1 = zs_read_reg(cs, 1); 245 c = zs_read_data(cs); 246 247 if (rr1 & (ZSRR1_FE | ZSRR1_DO | ZSRR1_PE)) { 248 /* Clear the receive error. */ 249 zs_write_csr(cs, ZSWR0_RESET_ERRORS); 250 } 251 252 if (c == KGDB_START) { 253 zskgdb(cs); 254 } else { 255 kgdb_input_lost++; 256 } 257 } 258 259 static void 260 zs_kgdb_txint(struct zs_chanstate *cs) 261 { 262 register int rr0; 263 264 rr0 = zs_read_csr(cs); 265 zs_write_csr(cs, ZSWR0_RESET_TXINT); 266 } 267 268 static void 269 zs_kgdb_stint(struct zs_chanstate *cs, int force) 270 { 271 register int rr0; 272 273 rr0 = zs_read_csr(cs); 274 zs_write_csr(cs, ZSWR0_RESET_STATUS); 275 276 /* 277 * Check here for console break, so that we can abort 278 * even when interrupts are locking up the machine. 279 */ 280 if (rr0 & ZSRR0_BREAK) { 281 zskgdb(cs); 282 } 283 } 284 285 static void 286 zs_kgdb_softint(struct zs_chanstate *cs) 287 { 288 289 printf("zs_kgdb_softint?\n"); 290 } 291 292 struct zsops zsops_kgdb = { 293 zs_kgdb_rxint, /* receive char available */ 294 zs_kgdb_stint, /* external/status */ 295 zs_kgdb_txint, /* xmit buffer empty */ 296 zs_kgdb_softint, /* process software interrupt */ 297 }; 298 299 /* 300 * findzs() should return the address of the given zs channel. 301 * Here we count on the PROM to map in the required zs chips. 302 */ 303 static void * 304 findzs(int zs) 305 { 306 307 #if defined(SUN4) 308 if (CPU_ISSUN4) { 309 /* 310 * On sun4, we use hard-coded physical addresses 311 */ 312 #define ZS0_PHYS 0xf1000000 313 #define ZS1_PHYS 0xf0000000 314 #define ZS2_PHYS 0xe0000000 315 bus_space_handle_t bh; 316 bus_addr_t paddr; 317 318 switch (zs) { 319 case 0: 320 paddr = ZS0_PHYS; 321 break; 322 case 1: 323 paddr = ZS1_PHYS; 324 break; 325 case 2: 326 paddr = ZS2_PHYS; 327 break; 328 default: 329 return (NULL); 330 } 331 332 if (cpuinfo.cpu_type == CPUTYP_4_100) 333 /* Clear top bits of physical address on 4/100 */ 334 paddr &= ~0xf0000000; 335 336 /* 337 * Have the obio module figure out which virtual 338 * address the device is mapped to. 339 */ 340 if (obio_find_rom_map(paddr, PAGE_SIZE, &bh) != 0) 341 return (NULL); 342 343 return ((void *)bh); 344 } 345 #endif 346 347 #if defined(SUN4C) || defined(SUN4M) 348 if (CPU_ISSUN4C || CPU_ISSUN4M) { 349 int node; 350 351 node = firstchild(findroot()); 352 if (CPU_ISSUN4M) { 353 /* 354 * On sun4m machines zs is in "obio" tree. 355 */ 356 node = findnode(node, "obio"); 357 if (node == 0) 358 panic("findzs: no obio node"); 359 node = firstchild(node); 360 } 361 while ((node = findnode(node, "zs")) != 0) { 362 int nvaddrs, *vaddrs, vstore[10]; 363 364 if (prom_getpropint(node, "slave", -1) != zs) { 365 node = nextsibling(node); 366 continue; 367 } 368 369 /* 370 * On some machines (e.g. the Voyager), the zs 371 * device has multi-valued register properties. 372 */ 373 vaddrs = vstore; 374 nvaddrs = sizeof(vstore)/sizeof(vstore[0]); 375 if (prom_getprop(node, "address", sizeof(int), 376 &nvaddrs, &vaddrs) != 0) 377 return (NULL); 378 379 return ((void *)vaddrs[0]); 380 } 381 } 382 #endif 383 return (NULL); 384 } 385