1/* $NetBSD: zs_kgdb.c,v 1.9 2009/03/14 15:36:10 dsl 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 1.9 2009/03/14 15:36:10 dsl 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 70void zs_kgdb_init(void); 71void zskgdb(struct zs_chanstate *cs); 72 73static void zs_setparam(struct zs_chanstate *, int, int); 74static struct zsops zsops_kgdb; 75 76extern struct zschan *zs_get_chan_addr (int zs_unit, int channel); 77extern int zs_getc(void *arg); 78extern void zs_putc(void *arg, int c); 79 80static 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 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); 112 113 cs->cs_preg[5] |= ZSWR5_DTR | ZSWR5_RTS; 114 cs->cs_preg[12] = tconst; 115 cs->cs_preg[13] = tconst >> 8; 116 117 s = splhigh(); 118 zs_loadchannelregs(cs); 119 splx(s); 120} 121 122/* 123 * Set up for kgdb; called at boot time before configuration. 124 * KGDB interrupts will be enabled later when zs0 is configured. 125 * Called after cninit(), so printf() etc. works. 126 */ 127void 128zs_kgdb_init(void) 129{ 130 struct zschan *zc; 131 int channel, unit; 132 extern const struct cdevsw zstty_cdevsw; 133 134 if (cdevsw_lookup(kgdb_dev) != &zstty_cdevsw) 135 return; 136 137 unit = (kgdb_dev & 2) ? 2 : 0; 138 channel = kgdb_dev & 1; 139 printf("zs_kgdb_init: attaching serial%d at %d baud\n", 140 (kgdb_dev & 3), kgdb_rate); 141 142 zc = zs_get_chan_addr(unit, channel); 143 144 /* Attach KGDB comms functions to this device */ 145 kgdb_attach(zs_getc, zs_putc, (void *)zc); 146} 147 148/* 149 * This is a "hook" called by the MI zstty_attach driver 150 * to allow the tty to be "taken over" for exclusive use by kgdb. 151 * Return non-zero if this is the kgdb port. 152 * 153 * Set the speed to kgdb_rate, CS8, etc. 154 */ 155int 156zs_check_kgdb(struct zs_chanstate *cs, int dev) 157{ 158 159 if (dev != kgdb_dev) 160 return (0); 161 162 /* 163 * Yes, this is port in use by kgdb. 164 */ 165 cs->cs_private = NULL; 166 cs->cs_ops = &zsops_kgdb; 167 168 /* Now set parameters. (interrupts enabled) */ 169 zs_setparam(cs, 1, kgdb_rate); 170 171 return (1); 172} 173 174/* 175 * KGDB framing character received: enter kernel debugger. This probably 176 * should time out after a few seconds to avoid hanging on spurious input. 177 */ 178void 179zskgdb(struct zs_chanstate *cs) 180{ 181 int unit = minor(kgdb_dev); 182 183 printf("zstty%d: kgdb interrupt\n", unit); 184 /* This will trap into the debugger. */ 185 kgdb_connect(1); 186} 187 188 189/**************************************************************** 190 * Interface to the lower layer (zscc) 191 ****************************************************************/ 192 193static void zs_kgdb_rxint(struct zs_chanstate *); 194static void zs_kgdb_stint(struct zs_chanstate *, int); 195static void zs_kgdb_txint(struct zs_chanstate *); 196static void zs_kgdb_softint(struct zs_chanstate *); 197 198static struct zsops zsops_kgdb = { 199 zs_kgdb_rxint, /* receive char available */ 200 zs_kgdb_stint, /* external/status */ 201 zs_kgdb_txint, /* xmit buffer empty */ 202 zs_kgdb_softint, /* process software interrupt */ 203}; 204 205int kgdb_input_lost; 206 207static void 208zs_kgdb_rxint(struct zs_chanstate *cs) 209{ 210 register u_char c, rr1; 211 212 /* 213 * First read the status, because reading the received char 214 * destroys the status of this char. 215 */ 216 rr1 = zs_read_reg(cs, 1); 217 c = zs_read_data(cs); 218 219 if (rr1 & (ZSRR1_FE | ZSRR1_DO | ZSRR1_PE)) { 220 /* Clear the receive error. */ 221 zs_write_csr(cs, ZSWR0_RESET_ERRORS); 222 } 223 224 if (c == KGDB_START) { 225 zskgdb(cs); 226 } else { 227 kgdb_input_lost++; 228 } 229} 230 231static void 232zs_kgdb_txint(register struct zs_chanstate *cs) 233{ 234 register int rr0; 235 236 rr0 = zs_read_csr(cs); 237 zs_write_csr(cs, ZSWR0_RESET_TXINT); 238} 239 240static void 241zs_kgdb_stint(register struct zs_chanstate *cs, int force) 242{ 243 register int rr0; 244 245 rr0 = zs_read_csr(cs); 246 zs_write_csr(cs, ZSWR0_RESET_STATUS); 247 248 /* 249 * Check here for console break, so that we can abort 250 * even when interrupts are locking up the machine. 251 */ 252 if (rr0 & ZSRR0_BREAK) { 253 zskgdb(cs); 254 } 255} 256 257static void 258zs_kgdb_softint(struct zs_chanstate *cs) 259{ 260 printf("zs_kgdb_softint?\n"); 261} 262 263 264