1 /* $NetBSD: zs_kgdb.c,v 1.5 2005/12/11 12:18:13 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 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 * 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 1.5 2005/12/11 12:18:13 christos 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/ic/z8530reg.h> 64 #include <machine/z8530var.h> 65 66 /* 67 * Hooks for kgdb when attached via the z8530 driver 68 * 69 * To use this, build a kernel with: option KGDB, and 70 * boot that kernel with "-d". (The kernel will call 71 * zs_kgdb_init, kgdb_connect.) When the console prints 72 * "kgdb waiting..." you run "gdb -k kernel" and do: 73 * (gdb) set remotebaud 19200 74 * (gdb) target remote /dev/ttyb 75 */ 76 77 void zs_kgdb_init __P((void)); 78 void zskgdb __P((struct zs_chanstate *cs)); 79 80 static void zs_setparam __P((struct zs_chanstate *, int, int)); 81 static struct zsops zsops_kgdb; 82 83 extern struct zschan *zs_get_chan_addr (int zs_unit, int channel); 84 extern int zs_getc __P((void *arg)); 85 extern void zs_putc __P((void *arg, int c)); 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 static void 107 zs_setparam(cs, iena, rate) 108 struct zs_chanstate *cs; 109 int iena; 110 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); 122 123 cs->cs_preg[5] |= ZSWR5_DTR | ZSWR5_RTS; 124 cs->cs_preg[12] = tconst; 125 cs->cs_preg[13] = tconst >> 8; 126 127 s = splhigh(); 128 zs_loadchannelregs(cs); 129 splx(s); 130 } 131 132 /* 133 * Set up for kgdb; called at boot time before configuration. 134 * KGDB interrupts will be enabled later when zs0 is configured. 135 * Called after cninit(), so printf() etc. works. 136 */ 137 void 138 zs_kgdb_init() 139 { 140 volatile struct zschan *zc; 141 int channel, unit; 142 extern const struct cdevsw zstty_cdevsw; 143 144 if (cdevsw_lookup(kgdb_dev) != &zstty_cdevsw) 145 return; 146 147 unit = (kgdb_dev & 2) ? 2 : 0; 148 channel = kgdb_dev & 1; 149 printf("zs_kgdb_init: attaching serial%d at %d baud\n", 150 (kgdb_dev & 3), kgdb_rate); 151 152 zc = zs_get_chan_addr(unit, channel); 153 154 /* Attach KGDB comms functions to this device */ 155 kgdb_attach(zs_getc, zs_putc, (void *)zc); 156 } 157 158 /* 159 * This is a "hook" called by the MI zstty_attach driver 160 * to allow the tty to be "taken over" for exclusive use by kgdb. 161 * Return non-zero if this is the kgdb port. 162 * 163 * Set the speed to kgdb_rate, CS8, etc. 164 */ 165 int 166 zs_check_kgdb(cs, dev) 167 struct zs_chanstate *cs; 168 int dev; 169 { 170 171 if (dev != kgdb_dev) 172 return (0); 173 174 /* 175 * Yes, this is port in use by kgdb. 176 */ 177 cs->cs_private = NULL; 178 cs->cs_ops = &zsops_kgdb; 179 180 /* Now set parameters. (interrupts enabled) */ 181 zs_setparam(cs, 1, kgdb_rate); 182 183 return (1); 184 } 185 186 /* 187 * KGDB framing character received: enter kernel debugger. This probably 188 * should time out after a few seconds to avoid hanging on spurious input. 189 */ 190 void 191 zskgdb(cs) 192 struct zs_chanstate *cs; 193 { 194 int unit = minor(kgdb_dev); 195 196 printf("zstty%d: kgdb interrupt\n", unit); 197 /* This will trap into the debugger. */ 198 kgdb_connect(1); 199 } 200 201 202 /**************************************************************** 203 * Interface to the lower layer (zscc) 204 ****************************************************************/ 205 206 static void zs_kgdb_rxint __P((struct zs_chanstate *)); 207 static void zs_kgdb_stint __P((struct zs_chanstate *, int)); 208 static void zs_kgdb_txint __P((struct zs_chanstate *)); 209 static void zs_kgdb_softint __P((struct zs_chanstate *)); 210 211 static struct zsops zsops_kgdb = { 212 zs_kgdb_rxint, /* receive char available */ 213 zs_kgdb_stint, /* external/status */ 214 zs_kgdb_txint, /* xmit buffer empty */ 215 zs_kgdb_softint, /* process software interrupt */ 216 }; 217 218 int kgdb_input_lost; 219 220 static void 221 zs_kgdb_rxint(cs) 222 struct zs_chanstate *cs; 223 { 224 register u_char c, rr1; 225 226 /* 227 * First read the status, because reading the received char 228 * destroys the status of this char. 229 */ 230 rr1 = zs_read_reg(cs, 1); 231 c = zs_read_data(cs); 232 233 if (rr1 & (ZSRR1_FE | ZSRR1_DO | ZSRR1_PE)) { 234 /* Clear the receive error. */ 235 zs_write_csr(cs, ZSWR0_RESET_ERRORS); 236 } 237 238 if (c == KGDB_START) { 239 zskgdb(cs); 240 } else { 241 kgdb_input_lost++; 242 } 243 } 244 245 static void 246 zs_kgdb_txint(cs) 247 register struct zs_chanstate *cs; 248 { 249 register int rr0; 250 251 rr0 = zs_read_csr(cs); 252 zs_write_csr(cs, ZSWR0_RESET_TXINT); 253 } 254 255 static void 256 zs_kgdb_stint(cs, force) 257 register struct zs_chanstate *cs; 258 int force; 259 { 260 register int rr0; 261 262 rr0 = zs_read_csr(cs); 263 zs_write_csr(cs, ZSWR0_RESET_STATUS); 264 265 /* 266 * Check here for console break, so that we can abort 267 * even when interrupts are locking up the machine. 268 */ 269 if (rr0 & ZSRR0_BREAK) { 270 zskgdb(cs); 271 } 272 } 273 274 static void 275 zs_kgdb_softint(cs) 276 struct zs_chanstate *cs; 277 { 278 printf("zs_kgdb_softint?\n"); 279 } 280 281 282