1 /* $NetBSD: zs_kgdb.c,v 1.7 2008/04/28 20:23:28 martin 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 and Wayne Knowles. 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 1.7 2008/04/28 20:23:28 martin Exp $"); 45 46 #include <sys/param.h> 47 #include <sys/systm.h> 48 #include <sys/proc.h> 49 #include <sys/device.h> 50 #include <sys/conf.h> 51 #include <sys/ioctl.h> 52 #include <sys/kernel.h> 53 #include <sys/syslog.h> 54 #include <sys/kgdb.h> 55 56 #include <dev/ic/z8530reg.h> 57 #include <machine/z8530var.h> 58 59 /* 60 * Hooks for kgdb when attached via the z8530 driver 61 * 62 * To use this, build a kernel with: option KGDB, and 63 * boot that kernel with "-d". (The kernel will call 64 * zs_kgdb_init, kgdb_connect.) When the console prints 65 * "kgdb waiting..." you run "gdb -k kernel" and do: 66 * (gdb) set remotebaud 19200 67 * (gdb) target remote /dev/ttyb 68 */ 69 70 void zs_kgdb_init __P((void)); 71 void zskgdb __P((struct zs_chanstate *cs)); 72 73 static void zs_setparam __P((struct zs_chanstate *, int, int)); 74 static struct zsops zsops_kgdb; 75 76 extern struct zschan *zs_get_chan_addr (int zs_unit, int channel); 77 extern int zs_getc __P((void *arg)); 78 extern void zs_putc __P((void *arg, int c)); 79 80 static u_char zs_kgdb_regs[16] = { 81 0, /* 0: CMD (reset, etc.) */ 82 0, /* 1: No interrupts yet. */ 83 0, /* 2: IVECT */ 84 ZSWR3_RX_8 | ZSWR3_RX_ENABLE, 85 ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP, 86 ZSWR5_TX_8 | ZSWR5_TX_ENABLE, 87 0, /* 6: TXSYNC/SYNCLO */ 88 0, /* 7: RXSYNC/SYNCHI */ 89 0, /* 8: alias for data port */ 90 ZSWR9_MASTER_IE | ZSWR9_NO_VECTOR, 91 0, /*10: Misc. TX/RX control bits */ 92 ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD, 93 14, /*12: BAUDLO (default=9600) */ 94 0, /*13: BAUDHI (default=9600) */ 95 ZSWR14_BAUD_ENA | ZSWR14_BAUD_FROM_PCLK, 96 ZSWR15_BREAK_IE, 97 }; 98 99 static void 100 zs_setparam(cs, iena, rate) 101 struct zs_chanstate *cs; 102 int iena; 103 int rate; 104 { 105 int s, tconst; 106 107 memcpy(cs->cs_preg, zs_kgdb_regs, 16); 108 109 if (iena) { 110 cs->cs_preg[1] = ZSWR1_RIE | ZSWR1_SIE; 111 } 112 113 /* Initialize the speed, etc. */ 114 tconst = BPS_TO_TCONST(cs->cs_brg_clk, rate); 115 116 cs->cs_preg[5] |= ZSWR5_DTR | ZSWR5_RTS; 117 cs->cs_preg[12] = tconst; 118 cs->cs_preg[13] = tconst >> 8; 119 120 s = splhigh(); 121 zs_loadchannelregs(cs); 122 splx(s); 123 } 124 125 /* 126 * Set up for kgdb; called at boot time before configuration. 127 * KGDB interrupts will be enabled later when zs0 is configured. 128 * Called after cninit(), so printf() etc. works. 129 */ 130 void 131 zs_kgdb_init() 132 { 133 struct zschan *zc; 134 int channel, unit; 135 extern const struct cdevsw zstty_cdevsw; 136 137 if (cdevsw_lookup(kgdb_dev) != &zstty_cdevsw) 138 return; 139 140 unit = (kgdb_dev & 2) ? 2 : 0; 141 channel = kgdb_dev & 1; 142 printf("zs_kgdb_init: attaching serial%d at %d baud\n", 143 (kgdb_dev & 3), kgdb_rate); 144 145 zc = zs_get_chan_addr(unit, channel); 146 147 /* Attach KGDB comms functions to this device */ 148 kgdb_attach(zs_getc, zs_putc, (void *)zc); 149 } 150 151 /* 152 * This is a "hook" called by the MI zstty_attach driver 153 * to allow the tty to be "taken over" for exclusive use by kgdb. 154 * Return non-zero if this is the kgdb port. 155 * 156 * Set the speed to kgdb_rate, CS8, etc. 157 */ 158 int 159 zs_check_kgdb(cs, dev) 160 struct zs_chanstate *cs; 161 int dev; 162 { 163 164 if (dev != kgdb_dev) 165 return (0); 166 167 /* 168 * Yes, this is port in use by kgdb. 169 */ 170 cs->cs_private = NULL; 171 cs->cs_ops = &zsops_kgdb; 172 173 /* Now set parameters. (interrupts enabled) */ 174 zs_setparam(cs, 1, kgdb_rate); 175 176 return (1); 177 } 178 179 /* 180 * KGDB framing character received: enter kernel debugger. This probably 181 * should time out after a few seconds to avoid hanging on spurious input. 182 */ 183 void 184 zskgdb(cs) 185 struct zs_chanstate *cs; 186 { 187 int unit = minor(kgdb_dev); 188 189 printf("zstty%d: kgdb interrupt\n", unit); 190 /* This will trap into the debugger. */ 191 kgdb_connect(1); 192 } 193 194 195 /**************************************************************** 196 * Interface to the lower layer (zscc) 197 ****************************************************************/ 198 199 static void zs_kgdb_rxint __P((struct zs_chanstate *)); 200 static void zs_kgdb_stint __P((struct zs_chanstate *, int)); 201 static void zs_kgdb_txint __P((struct zs_chanstate *)); 202 static void zs_kgdb_softint __P((struct zs_chanstate *)); 203 204 static struct zsops zsops_kgdb = { 205 zs_kgdb_rxint, /* receive char available */ 206 zs_kgdb_stint, /* external/status */ 207 zs_kgdb_txint, /* xmit buffer empty */ 208 zs_kgdb_softint, /* process software interrupt */ 209 }; 210 211 int kgdb_input_lost; 212 213 static void 214 zs_kgdb_rxint(cs) 215 struct zs_chanstate *cs; 216 { 217 register u_char c, rr1; 218 219 /* 220 * First read the status, because reading the received char 221 * destroys the status of this char. 222 */ 223 rr1 = zs_read_reg(cs, 1); 224 c = zs_read_data(cs); 225 226 if (rr1 & (ZSRR1_FE | ZSRR1_DO | ZSRR1_PE)) { 227 /* Clear the receive error. */ 228 zs_write_csr(cs, ZSWR0_RESET_ERRORS); 229 } 230 231 if (c == KGDB_START) { 232 zskgdb(cs); 233 } else { 234 kgdb_input_lost++; 235 } 236 } 237 238 static void 239 zs_kgdb_txint(cs) 240 register struct zs_chanstate *cs; 241 { 242 register int rr0; 243 244 rr0 = zs_read_csr(cs); 245 zs_write_csr(cs, ZSWR0_RESET_TXINT); 246 } 247 248 static void 249 zs_kgdb_stint(cs, force) 250 register struct zs_chanstate *cs; 251 int force; 252 { 253 register int rr0; 254 255 rr0 = zs_read_csr(cs); 256 zs_write_csr(cs, ZSWR0_RESET_STATUS); 257 258 /* 259 * Check here for console break, so that we can abort 260 * even when interrupts are locking up the machine. 261 */ 262 if (rr0 & ZSRR0_BREAK) { 263 zskgdb(cs); 264 } 265 } 266 267 static void 268 zs_kgdb_softint(cs) 269 struct zs_chanstate *cs; 270 { 271 printf("zs_kgdb_softint?\n"); 272 } 273 274 275