1 /* $NetBSD: zs_kgdb.c,v 1.16 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/ic/z8530reg.h> 61 #include <machine/z8530var.h> 62 #include <sun3/dev/zs_cons.h> 63 64 /* The Sun3 provides a 4.9152 MHz clock to the ZS chips. */ 65 #define PCLK (9600 * 512) /* PCLK pin input clock rate */ 66 #define ZSHARD_PRI 6 /* Wired on the CPU board... */ 67 68 #define ZS_DELAY() delay(2) 69 70 /* The layout of this is hardware-dependent (padding, order). */ 71 struct zschan { 72 volatile u_char zc_csr; /* ctrl,status, and indirect access */ 73 u_char zc_xxx0; 74 volatile u_char zc_data; /* data */ 75 u_char zc_xxx1; 76 }; 77 78 static void zs_setparam __P((struct zs_chanstate *, int, int)); 79 static void zskgdb __P((struct zs_chanstate *)); 80 81 struct zsops zsops_kgdb; 82 83 static u_char zs_kgdb_regs[16] = { 84 0, /* 0: CMD (reset, etc.) */ 85 0, /* 1: ~(ZSWR1_RIE | ZSWR1_TIE | ZSWR1_SIE) */ 86 0x18 + ZSHARD_PRI, /* IVECT */ 87 ZSWR3_RX_8 | ZSWR3_RX_ENABLE, 88 ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP, 89 ZSWR5_TX_8 | ZSWR5_TX_ENABLE, 90 0, /* 6: TXSYNC/SYNCLO */ 91 0, /* 7: RXSYNC/SYNCHI */ 92 0, /* 8: alias for data port */ 93 ZSWR9_MASTER_IE, 94 0, /*10: Misc. TX/RX control bits */ 95 ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD, 96 14, /*12: BAUDLO (default=9600) */ 97 0, /*13: BAUDHI (default=9600) */ 98 ZSWR14_BAUD_FROM_PCLK | ZSWR14_BAUD_ENA, 99 ZSWR15_BREAK_IE, 100 }; 101 102 /* 103 * This replaces "zs_reset()" in the sparc driver. 104 */ 105 static void 106 zs_setparam(cs, iena, rate) 107 struct zs_chanstate *cs; 108 int iena; 109 int rate; 110 { 111 int s, tconst; 112 113 memcpy(cs->cs_preg, zs_kgdb_regs, 16); 114 115 if (iena) { 116 cs->cs_preg[1] = ZSWR1_RIE | ZSWR1_SIE; 117 } 118 119 /* Initialize the speed, etc. */ 120 tconst = BPS_TO_TCONST(cs->cs_brg_clk, rate); 121 cs->cs_preg[5] |= ZSWR5_DTR | ZSWR5_RTS; 122 cs->cs_preg[12] = tconst; 123 cs->cs_preg[13] = tconst >> 8; 124 125 s = splhigh(); 126 zs_loadchannelregs(cs); 127 splx(s); 128 } 129 130 /* 131 * Set up for kgdb; called at boot time before configuration. 132 * KGDB interrupts will be enabled later when zs0 is configured. 133 * Called after cninit(), so printf() etc. works. 134 */ 135 void 136 zs_kgdb_init() 137 { 138 struct zs_chanstate cs; 139 volatile struct zschan *zc; 140 int channel, zsc_unit; 141 extern const struct cdevsw zstty_cdevsw; 142 143 /* printf("zs_kgdb_init: kgdb_dev=0x%x\n", kgdb_dev); */ 144 if (cdevsw_lookup(kgdb_dev) != &zstty_cdevsw) 145 return; 146 147 /* Note: (ttya,ttyb) on zsc1, and (ttyc,ttyd) on zsc0 */ 148 zsc_unit = (kgdb_dev & 2) ? 0 : 1; 149 channel = kgdb_dev & 1; 150 printf("zs_kgdb_init: attaching tty%c at %d baud\n", 151 'a' + (kgdb_dev & 3), kgdb_rate); 152 153 /* Setup temporary chanstate. */ 154 memset((caddr_t)&cs, 0, sizeof(cs)); 155 zc = zs_get_chan_addr(zsc_unit, channel); 156 if (zc == NULL) { 157 printf("zs_kgdb_init: zs not mapped.\n"); 158 kgdb_dev = -1; 159 return; 160 } 161 162 cs.cs_channel = channel; 163 cs.cs_brg_clk = PCLK / 16; 164 cs.cs_reg_csr = &zc->zc_csr; 165 cs.cs_reg_data = &zc->zc_data; 166 167 /* Now set parameters. (interrupts disabled) */ 168 zs_setparam(&cs, 0, kgdb_rate); 169 170 /* Store the getc/putc functions and arg. */ 171 kgdb_attach(zs_getc, zs_putc, (void *)zc); 172 } 173 174 /* 175 * This is a "hook" called by zstty_attach to allow the tty 176 * to be "taken over" for exclusive use by kgdb. 177 * Return non-zero if this is the kgdb port. 178 * 179 * Set the speed to kgdb_rate, CS8, etc. 180 */ 181 int 182 zs_check_kgdb(cs, dev) 183 struct zs_chanstate *cs; 184 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 static void 207 zskgdb(cs) 208 struct zs_chanstate *cs; 209 { 210 int unit = minor(kgdb_dev); 211 212 printf("zstty%d: kgdb interrupt\n", unit); 213 /* This will trap into the debugger. */ 214 kgdb_connect(1); 215 } 216 217 218 /**************************************************************** 219 * Interface to the lower layer (zscc) 220 ****************************************************************/ 221 222 static void zs_kgdb_rxint __P((struct zs_chanstate *)); 223 static void zs_kgdb_stint __P((struct zs_chanstate *, int)); 224 static void zs_kgdb_txint __P((struct zs_chanstate *)); 225 static void zs_kgdb_softint __P((struct zs_chanstate *)); 226 227 int kgdb_input_lost; 228 229 static void 230 zs_kgdb_rxint(cs) 231 struct zs_chanstate *cs; 232 { 233 u_char c, rr1; 234 235 /* 236 * First read the status, because reading the received char 237 * destroys the status of this char. 238 */ 239 rr1 = zs_read_reg(cs, 1); 240 c = zs_read_data(cs); 241 242 if (rr1 & (ZSRR1_FE | ZSRR1_DO | ZSRR1_PE)) { 243 /* Clear the receive error. */ 244 zs_write_csr(cs, ZSWR0_RESET_ERRORS); 245 } 246 247 if (c == KGDB_START) { 248 zskgdb(cs); 249 } else { 250 kgdb_input_lost++; 251 } 252 } 253 254 static void 255 zs_kgdb_txint(cs) 256 struct zs_chanstate *cs; 257 { 258 int rr0; 259 260 rr0 = zs_read_csr(cs); 261 zs_write_csr(cs, ZSWR0_RESET_TXINT); 262 } 263 264 static void 265 zs_kgdb_stint(cs, force) 266 struct zs_chanstate *cs; 267 int force; 268 { 269 int rr0; 270 271 rr0 = zs_read_csr(cs); 272 zs_write_csr(cs, ZSWR0_RESET_STATUS); 273 274 /* 275 * Check here for console break, so that we can abort 276 * even when interrupts are locking up the machine. 277 */ 278 if (rr0 & ZSRR0_BREAK) { 279 zskgdb(cs); 280 } 281 } 282 283 static void 284 zs_kgdb_softint(cs) 285 struct zs_chanstate *cs; 286 { 287 printf("zs_kgdb_softint?\n"); 288 } 289 290 struct zsops zsops_kgdb = { 291 zs_kgdb_rxint, /* receive char available */ 292 zs_kgdb_stint, /* external/status */ 293 zs_kgdb_txint, /* xmit buffer empty */ 294 zs_kgdb_softint, /* process software interrupt */ 295 }; 296