1 /* $NetBSD: zs_kgdb.c,v 1.21 2009/05/16 16:55:24 cegger 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 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 /* 33 * Hooks for kgdb when attached via the z8530 driver 34 * 35 * To use this, build a kernel with: option KGDB, and 36 * boot that kernel with "-d". (The kernel will call 37 * zs_kgdb_init, kgdb_connect.) When the console prints 38 * "kgdb waiting..." you run "gdb -k kernel" and do: 39 * (gdb) set remotebaud 19200 40 * (gdb) target remote /dev/ttyb 41 */ 42 43 #include <sys/cdefs.h> 44 __KERNEL_RCSID(0, "$NetBSD: zs_kgdb.c,v 1.21 2009/05/16 16:55:24 cegger Exp $"); 45 46 #include "opt_kgdb.h" 47 48 #include <sys/param.h> 49 #include <sys/systm.h> 50 #include <sys/proc.h> 51 #include <sys/device.h> 52 #include <sys/conf.h> 53 #include <sys/ioctl.h> 54 #include <sys/kernel.h> 55 #include <sys/syslog.h> 56 #include <sys/kgdb.h> 57 58 #include <dev/ic/z8530reg.h> 59 #include <machine/z8530var.h> 60 #include <machine/autoconf.h> 61 #include <machine/promlib.h> 62 #include <sparc/dev/cons.h> 63 64 /* Suns provide a 4.9152 MHz clock to the ZS chips. */ 65 #define PCLK (9600 * 512) /* PCLK pin input clock rate */ 66 67 /* The layout of this is hardware-dependent (padding, order). */ 68 struct zschan { 69 volatile u_char zc_csr; /* ctrl,status, and indirect access */ 70 u_char zc_xxx0; 71 volatile u_char zc_data; /* data */ 72 u_char zc_xxx1; 73 }; 74 struct zsdevice { 75 /* Yes, they are backwards. */ 76 struct zschan zs_chan_b; 77 struct zschan zs_chan_a; 78 }; 79 80 static void zs_setparam(struct zs_chanstate *, int, int); 81 static void *findzs(int); 82 struct zsops zsops_kgdb; 83 84 extern int zs_getc(void *); 85 extern void zs_putc(void *, int); 86 87 static u_char zs_kgdb_regs[16] = { 88 0, /* 0: CMD (reset, etc.) */ 89 0, /* 1: No interrupts yet. */ 90 0, /* 2: IVECT */ 91 ZSWR3_RX_8 | ZSWR3_RX_ENABLE, 92 ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP, 93 ZSWR5_TX_8 | ZSWR5_TX_ENABLE, 94 0, /* 6: TXSYNC/SYNCLO */ 95 0, /* 7: RXSYNC/SYNCHI */ 96 0, /* 8: alias for data port */ 97 ZSWR9_MASTER_IE | ZSWR9_NO_VECTOR, 98 0, /*10: Misc. TX/RX control bits */ 99 ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD, 100 14, /*12: BAUDLO (default=9600) */ 101 0, /*13: BAUDHI (default=9600) */ 102 ZSWR14_BAUD_ENA | ZSWR14_BAUD_FROM_PCLK, 103 ZSWR15_BREAK_IE, 104 }; 105 106 /* 107 * This replaces "zs_reset()" in the sparc driver. 108 */ 109 static void 110 zs_setparam(struct zs_chanstate *cs, int iena, int rate) 111 { 112 int s, tconst; 113 114 memcpy(cs->cs_preg, zs_kgdb_regs, 16); 115 116 if (iena) { 117 cs->cs_preg[1] = ZSWR1_RIE | ZSWR1_SIE; 118 } 119 120 /* Initialize the speed, etc. */ 121 tconst = BPS_TO_TCONST(cs->cs_brg_clk, rate); 122 cs->cs_preg[5] |= ZSWR5_DTR | ZSWR5_RTS; 123 cs->cs_preg[12] = tconst; 124 cs->cs_preg[13] = tconst >> 8; 125 126 s = splhigh(); 127 zs_loadchannelregs(cs); 128 splx(s); 129 } 130 131 /* 132 * Set up for kgdb; called at boot time before configuration. 133 * KGDB interrupts will be enabled later when zs0 is configured. 134 * Called after cninit(), so printf() etc. works. 135 */ 136 void 137 zs_kgdb_init(void) 138 { 139 struct zs_chanstate cs; 140 struct zsdevice *zsd; 141 volatile struct zschan *zc; 142 int channel, promzs_unit; 143 extern const struct cdevsw zstty_cdevsw; 144 145 /* printf("zs_kgdb_init: kgdb_dev=0x%x\n", kgdb_dev); */ 146 if (cdevsw_lookup(kgdb_dev) != &zstty_cdevsw) 147 return; 148 149 /* Note: (ttya,ttyb) on zs0, and (ttyc,ttyd) on zs2 */ 150 promzs_unit = (kgdb_dev & 2) ? 2 : 0; 151 channel = kgdb_dev & 1; 152 printf("zs_kgdb_init: attaching tty%c at %d baud\n", 153 'a' + (kgdb_dev & 3), kgdb_rate); 154 155 /* Setup temporary chanstate. */ 156 memset((void *)&cs, 0, sizeof(cs)); 157 zsd = findzs(promzs_unit); 158 if (zsd == NULL) { 159 printf("zs_kgdb_init: zs not mapped.\n"); 160 return; 161 } 162 zc = (channel == 0) ? &zsd->zs_chan_a : &zsd->zs_chan_b; 163 164 cs.cs_channel = channel; 165 cs.cs_brg_clk = PCLK / 16; 166 cs.cs_reg_csr = &zc->zc_csr; 167 cs.cs_reg_data = &zc->zc_data; 168 169 /* Now set parameters. (interrupts disabled) */ 170 zs_setparam(&cs, 0, kgdb_rate); 171 172 /* Store the getc/putc functions and arg. */ 173 kgdb_attach(zs_getc, zs_putc, __UNVOLATILE(zc)); 174 } 175 176 /* 177 * This is a "hook" called by zstty_attach to allow the tty 178 * to be "taken over" for exclusive use by kgdb. 179 * Return non-zero if this is the kgdb port. 180 * 181 * Set the speed to kgdb_rate, CS8, etc. 182 */ 183 int 184 zs_check_kgdb(struct zs_chanstate *cs, int dev) 185 { 186 187 if (dev != kgdb_dev) 188 return (0); 189 190 /* 191 * Yes, this is port in use by kgdb. 192 */ 193 cs->cs_private = NULL; 194 cs->cs_ops = &zsops_kgdb; 195 196 /* Now set parameters. (interrupts enabled) */ 197 zs_setparam(cs, 1, kgdb_rate); 198 199 return (1); 200 } 201 202 /* 203 * KGDB framing character received: enter kernel debugger. This probably 204 * should time out after a few seconds to avoid hanging on spurious input. 205 */ 206 void 207 zskgdb(struct zs_chanstate *cs) 208 { 209 int unit = minor(kgdb_dev); 210 211 printf("zstty%d: kgdb interrupt\n", unit); 212 /* This will trap into the debugger. */ 213 kgdb_connect(1); 214 } 215 216 217 /**************************************************************** 218 * Interface to the lower layer (zscc) 219 ****************************************************************/ 220 221 static void zs_kgdb_rxint(struct zs_chanstate *); 222 static void zs_kgdb_stint(struct zs_chanstate *, int); 223 static void zs_kgdb_txint(struct zs_chanstate *); 224 static void zs_kgdb_softint(struct zs_chanstate *); 225 226 int kgdb_input_lost; 227 228 static void 229 zs_kgdb_rxint(struct zs_chanstate *cs) 230 { 231 register u_char c, rr1; 232 233 /* 234 * First read the status, because reading the received char 235 * destroys the status of this char. 236 */ 237 rr1 = zs_read_reg(cs, 1); 238 c = zs_read_data(cs); 239 240 if (rr1 & (ZSRR1_FE | ZSRR1_DO | ZSRR1_PE)) { 241 /* Clear the receive error. */ 242 zs_write_csr(cs, ZSWR0_RESET_ERRORS); 243 } 244 245 if (c == KGDB_START) { 246 zskgdb(cs); 247 } else { 248 kgdb_input_lost++; 249 } 250 } 251 252 static void 253 zs_kgdb_txint(struct zs_chanstate *cs) 254 { 255 register int rr0; 256 257 rr0 = zs_read_csr(cs); 258 zs_write_csr(cs, ZSWR0_RESET_TXINT); 259 } 260 261 static void 262 zs_kgdb_stint(struct zs_chanstate *cs, int force) 263 { 264 register int rr0; 265 266 rr0 = zs_read_csr(cs); 267 zs_write_csr(cs, ZSWR0_RESET_STATUS); 268 269 /* 270 * Check here for console break, so that we can abort 271 * even when interrupts are locking up the machine. 272 */ 273 if (rr0 & ZSRR0_BREAK) { 274 zskgdb(cs); 275 } 276 } 277 278 static void 279 zs_kgdb_softint(struct zs_chanstate *cs) 280 { 281 282 printf("zs_kgdb_softint?\n"); 283 } 284 285 struct zsops zsops_kgdb = { 286 zs_kgdb_rxint, /* receive char available */ 287 zs_kgdb_stint, /* external/status */ 288 zs_kgdb_txint, /* xmit buffer empty */ 289 zs_kgdb_softint, /* process software interrupt */ 290 }; 291 292 /* 293 * findzs() should return the address of the given zs channel. 294 * Here we count on the PROM to map in the required zs chips. 295 */ 296 static void * 297 findzs(int zs) 298 { 299 300 #if defined(SUN4) 301 if (CPU_ISSUN4) { 302 /* 303 * On sun4, we use hard-coded physical addresses 304 */ 305 #define ZS0_PHYS 0xf1000000 306 #define ZS1_PHYS 0xf0000000 307 #define ZS2_PHYS 0xe0000000 308 bus_space_handle_t bh; 309 bus_addr_t paddr; 310 311 switch (zs) { 312 case 0: 313 paddr = ZS0_PHYS; 314 break; 315 case 1: 316 paddr = ZS1_PHYS; 317 break; 318 case 2: 319 paddr = ZS2_PHYS; 320 break; 321 default: 322 return (NULL); 323 } 324 325 if (cpuinfo.cpu_type == CPUTYP_4_100) 326 /* Clear top bits of physical address on 4/100 */ 327 paddr &= ~0xf0000000; 328 329 /* 330 * Have the obio module figure out which virtual 331 * address the device is mapped to. 332 */ 333 if (obio_find_rom_map(paddr, PAGE_SIZE, &bh) != 0) 334 return (NULL); 335 336 return ((void *)bh); 337 } 338 #endif 339 340 #if defined(SUN4C) || defined(SUN4M) 341 if (CPU_ISSUN4C || CPU_ISSUN4M) { 342 int node; 343 344 node = firstchild(findroot()); 345 if (CPU_ISSUN4M) { 346 /* 347 * On sun4m machines zs is in "obio" tree. 348 */ 349 node = findnode(node, "obio"); 350 if (node == 0) 351 panic("findzs: no obio node"); 352 node = firstchild(node); 353 } 354 while ((node = findnode(node, "zs")) != 0) { 355 int nvaddrs, *vaddrs, vstore[10]; 356 357 if (prom_getpropint(node, "slave", -1) != zs) { 358 node = nextsibling(node); 359 continue; 360 } 361 362 /* 363 * On some machines (e.g. the Voyager), the zs 364 * device has multi-valued register properties. 365 */ 366 vaddrs = vstore; 367 nvaddrs = sizeof(vstore)/sizeof(vstore[0]); 368 if (prom_getprop(node, "address", sizeof(int), 369 &nvaddrs, &vaddrs) != 0) 370 return (NULL); 371 372 return ((void *)vaddrs[0]); 373 } 374 } 375 #endif 376 return (NULL); 377 } 378