1/* $NetBSD: zs_kgdb.c,v 1.9 2007/10/17 19:57:43 garbled 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 1.9 2007/10/17 19:57:43 garbled 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/promlib.h> 61#include <sun2/dev/cons.h> 62 63static void zs_setparam(struct zs_chanstate *, int, int); 64struct zsops zsops_kgdb; 65 66extern int zs_getc(void *arg); 67extern void zs_putc(void *arg, int c); 68 69static u_char zs_kgdb_regs[16] = { 70 0, /* 0: CMD (reset, etc.) */ 71 0, /* 1: No interrupts yet. */ 72#ifdef ZS_INIT_IVECT 73 ZS_INIT_IVECT, /* 2: IVECT */ 74#else 75 0, /* 2: IVECT */ 76#endif 77 ZSWR3_RX_8 | ZSWR3_RX_ENABLE, 78 ZSWR4_CLK_X16 | ZSWR4_ONESB | ZSWR4_EVENP, 79 ZSWR5_TX_8 | ZSWR5_TX_ENABLE, 80 0, /* 6: TXSYNC/SYNCLO */ 81 0, /* 7: RXSYNC/SYNCHI */ 82 0, /* 8: alias for data port */ 83#ifdef ZS_INIT_IVECT 84 ZSWR9_MASTER_IE, 85#else 86 ZSWR9_MASTER_IE | ZSWR9_NO_VECTOR, 87#endif 88 0, /*10: Misc. TX/RX control bits */ 89 ZSWR11_TXCLK_BAUD | ZSWR11_RXCLK_BAUD, 90 14, /*12: BAUDLO (default=9600) */ 91 0, /*13: BAUDHI (default=9600) */ 92 ZSWR14_BAUD_ENA | ZSWR14_BAUD_FROM_PCLK, 93 ZSWR15_BREAK_IE, 94}; 95 96/* 97 * This replaces "zs_reset()" in the sparc driver. 98 */ 99static void 100zs_setparam(struct zs_chanstate *cs, int iena, int rate) 101{ 102 int s, tconst; 103 104 memcpy(cs->cs_preg, zs_kgdb_regs, 16); 105 106 if (iena) { 107 cs->cs_preg[1] = ZSWR1_RIE | ZSWR1_SIE; 108 } 109 110 /* Initialize the speed, etc. */ 111 tconst = BPS_TO_TCONST(cs->cs_brg_clk, rate); 112 cs->cs_preg[5] |= ZSWR5_DTR | ZSWR5_RTS; 113 cs->cs_preg[12] = tconst; 114 cs->cs_preg[13] = tconst >> 8; 115 116 s = splhigh(); 117 zs_loadchannelregs(cs); 118 splx(s); 119} 120 121/* 122 * Set up for kgdb; called at boot time before configuration. 123 * KGDB interrupts will be enabled later when zs0 is configured. 124 * Called after cninit(), so printf() etc. works. 125 */ 126void 127zs_kgdb_init(void) 128{ 129 struct zs_chanstate cs; 130 struct zsdevice *zsd; 131 volatile struct zschan *zc; 132 int channel, promzs_unit; 133 extern const struct cdevsw zstty_cdevsw; 134 135 /* printf("zs_kgdb_init: kgdb_dev=0x%x\n", kgdb_dev); */ 136 if (cdevsw_lookup(kgdb_dev) != &zstty_cdevsw) 137 return; 138 139 /* Note: (ttya,ttyb) on zs0, and (ttyc,ttyd) on zs2 */ 140 promzs_unit = (kgdb_dev & 2) ? 2 : 0; 141 channel = kgdb_dev & 1; 142 printf("zs_kgdb_init: attaching tty%c at %d baud\n", 143 'a' + (kgdb_dev & 3), kgdb_rate); 144 145 /* Setup temporary chanstate. */ 146 memset((void *)&cs, 0, sizeof(cs)); 147 zsd = zs_find_prom(promzs_unit); 148 if (zsd == NULL) { 149 printf("zs_kgdb_init: zs not mapped.\n"); 150 return; 151 } 152 zc = (channel == 0) ? &zsd->zs_chan_a : &zsd->zs_chan_b; 153 154 cs.cs_channel = channel; 155 cs.cs_brg_clk = PCLK / 16; 156 cs.cs_reg_csr = &zc->zc_csr; 157 cs.cs_reg_data = &zc->zc_data; 158 159 /* Now set parameters. (interrupts disabled) */ 160 zs_setparam(&cs, 0, kgdb_rate); 161 162 /* Store the getc/putc functions and arg. */ 163 kgdb_attach(zs_getc, zs_putc, __UNVOLATILE(zc)); 164} 165 166/* 167 * This is a "hook" called by zstty_attach to allow the tty 168 * to be "taken over" for exclusive use by kgdb. 169 * Return non-zero if this is the kgdb port. 170 * 171 * Set the speed to kgdb_rate, CS8, etc. 172 */ 173int 174zs_check_kgdb(struct zs_chanstate *cs, int dev) 175{ 176 177 if (dev != kgdb_dev) 178 return (0); 179 180 /* 181 * Yes, this is port in use by kgdb. 182 */ 183 cs->cs_private = NULL; 184 cs->cs_ops = &zsops_kgdb; 185 186 /* Now set parameters. (interrupts enabled) */ 187 zs_setparam(cs, 1, kgdb_rate); 188 189 return (1); 190} 191 192/* 193 * KGDB framing character received: enter kernel debugger. This probably 194 * should time out after a few seconds to avoid hanging on spurious input. 195 */ 196void 197zskgdb(struct zs_chanstate *cs) 198{ 199 int unit = minor(kgdb_dev); 200 201 printf("zstty%d: kgdb interrupt\n", unit); 202 /* This will trap into the debugger. */ 203 kgdb_connect(1); 204} 205 206 207/**************************************************************** 208 * Interface to the lower layer (zscc) 209 ****************************************************************/ 210 211static void zs_kgdb_rxint(struct zs_chanstate *); 212static void zs_kgdb_stint(struct zs_chanstate *, int); 213static void zs_kgdb_txint(struct zs_chanstate *); 214static void zs_kgdb_softint(struct zs_chanstate *); 215 216int kgdb_input_lost; 217 218static void 219zs_kgdb_rxint(struct zs_chanstate *cs) 220{ 221 u_char c, rr1; 222 223 /* 224 * First read the status, because reading the received char 225 * destroys the status of this char. 226 */ 227 rr1 = zs_read_reg(cs, 1); 228 c = zs_read_data(cs); 229 230 if (rr1 & (ZSRR1_FE | ZSRR1_DO | ZSRR1_PE)) { 231 /* Clear the receive error. */ 232 zs_write_csr(cs, ZSWR0_RESET_ERRORS); 233 } 234 235 if (c == KGDB_START) { 236 zskgdb(cs); 237 } else { 238 kgdb_input_lost++; 239 } 240} 241 242static void 243zs_kgdb_txint(struct zs_chanstate *cs) 244{ 245 int rr0; 246 247 rr0 = zs_read_csr(cs); 248 zs_write_csr(cs, ZSWR0_RESET_TXINT); 249} 250 251static void 252zs_kgdb_stint(struct zs_chanstate *cs, int force) 253{ 254 int rr0; 255 256 rr0 = zs_read_csr(cs); 257 zs_write_csr(cs, ZSWR0_RESET_STATUS); 258 259 /* 260 * Check here for console break, so that we can abort 261 * even when interrupts are locking up the machine. 262 */ 263 if (rr0 & ZSRR0_BREAK) { 264 zskgdb(cs); 265 } 266} 267 268static void 269zs_kgdb_softint(struct zs_chanstate *cs) 270{ 271 printf("zs_kgdb_softint?\n"); 272} 273 274struct zsops zsops_kgdb = { 275 zs_kgdb_rxint, /* receive char available */ 276 zs_kgdb_stint, /* external/status */ 277 zs_kgdb_txint, /* xmit buffer empty */ 278 zs_kgdb_softint, /* process software interrupt */ 279}; 280