1/* $NetBSD: z8530sc.c,v 1.29 2009/03/20 16:28:57 tsutsui Exp $ */ 2 3/* 4 * Copyright (c) 1992, 1993 5 * The Regents of the University of California. All rights reserved. 6 * 7 * This software was developed by the Computer Systems Engineering group 8 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 9 * contributed to Berkeley. 10 * 11 * All advertising materials mentioning features or use of this software 12 * must display the following acknowledgement: 13 * This product includes software developed by the University of 14 * California, Lawrence Berkeley Laboratory. 15 * 16 * Redistribution and use in source and binary forms, with or without 17 * modification, are permitted provided that the following conditions 18 * are met: 19 * 1. Redistributions of source code must retain the above copyright 20 * notice, this list of conditions and the following disclaimer. 21 * 2. Redistributions in binary form must reproduce the above copyright 22 * notice, this list of conditions and the following disclaimer in the 23 * documentation and/or other materials provided with the distribution. 24 * 3. Neither the name of the University nor the names of its contributors 25 * may be used to endorse or promote products derived from this software 26 * without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 38 * SUCH DAMAGE. 39 * 40 * @(#)zs.c 8.1 (Berkeley) 7/19/93 41 */ 42 43/* 44 * Copyright (c) 1994 Gordon W. Ross 45 * 46 * This software was developed by the Computer Systems Engineering group 47 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and 48 * contributed to Berkeley. 49 * 50 * All advertising materials mentioning features or use of this software 51 * must display the following acknowledgement: 52 * This product includes software developed by the University of 53 * California, Lawrence Berkeley Laboratory. 54 * 55 * Redistribution and use in source and binary forms, with or without 56 * modification, are permitted provided that the following conditions 57 * are met: 58 * 1. Redistributions of source code must retain the above copyright 59 * notice, this list of conditions and the following disclaimer. 60 * 2. Redistributions in binary form must reproduce the above copyright 61 * notice, this list of conditions and the following disclaimer in the 62 * documentation and/or other materials provided with the distribution. 63 * 3. All advertising materials mentioning features or use of this software 64 * must display the following acknowledgement: 65 * This product includes software developed by the University of 66 * California, Berkeley and its contributors. 67 * 4. Neither the name of the University nor the names of its contributors 68 * may be used to endorse or promote products derived from this software 69 * without specific prior written permission. 70 * 71 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 72 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 73 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 74 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 75 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 76 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 77 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 78 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 79 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 80 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 81 * SUCH DAMAGE. 82 * 83 * @(#)zs.c 8.1 (Berkeley) 7/19/93 84 */ 85 86/* 87 * Zilog Z8530 Dual UART driver (common part) 88 * 89 * This file contains the machine-independent parts of the 90 * driver common to tty and keyboard/mouse sub-drivers. 91 */ 92 93#include <sys/cdefs.h> 94__KERNEL_RCSID(0, "$NetBSD: z8530sc.c,v 1.29 2009/03/20 16:28:57 tsutsui Exp $"); 95 96#include <sys/param.h> 97#include <sys/systm.h> 98#include <sys/proc.h> 99#include <sys/device.h> 100#include <sys/conf.h> 101#include <sys/file.h> 102#include <sys/ioctl.h> 103#include <sys/tty.h> 104#include <sys/time.h> 105#include <sys/kernel.h> 106#include <sys/syslog.h> 107 108#include <dev/ic/z8530reg.h> 109#include <machine/z8530var.h> 110 111void 112zs_break(struct zs_chanstate *cs, int set) 113{ 114 115 if (set) { 116 cs->cs_preg[5] |= ZSWR5_BREAK; 117 cs->cs_creg[5] |= ZSWR5_BREAK; 118 } else { 119 cs->cs_preg[5] &= ~ZSWR5_BREAK; 120 cs->cs_creg[5] &= ~ZSWR5_BREAK; 121 } 122 zs_write_reg(cs, 5, cs->cs_creg[5]); 123} 124 125 126/* 127 * drain on-chip fifo 128 */ 129void 130zs_iflush(struct zs_chanstate *cs) 131{ 132 uint8_t c, rr0, rr1; 133 int i; 134 135 /* 136 * Count how many times we loop. Some systems, such as some 137 * Apple PowerBooks, claim to have SCC's which they really don't. 138 */ 139 for (i = 0; i < 32; i++) { 140 /* Is there input available? */ 141 rr0 = zs_read_csr(cs); 142 if ((rr0 & ZSRR0_RX_READY) == 0) 143 break; 144 145 /* 146 * First read the status, because reading the data 147 * destroys the status of this char. 148 */ 149 rr1 = zs_read_reg(cs, 1); 150 c = zs_read_data(cs); 151 152 if (rr1 & (ZSRR1_FE | ZSRR1_DO | ZSRR1_PE)) { 153 /* Clear the receive error. */ 154 zs_write_csr(cs, ZSWR0_RESET_ERRORS); 155 } 156 } 157} 158 159 160/* 161 * Write the given register set to the given zs channel in the proper order. 162 * The channel must not be transmitting at the time. The receiver will 163 * be disabled for the time it takes to write all the registers. 164 * Call this with interrupts disabled. 165 */ 166void 167zs_loadchannelregs(struct zs_chanstate *cs) 168{ 169 uint8_t *reg, v; 170 171 zs_write_csr(cs, ZSM_RESET_ERR); /* XXX: reset error condition */ 172 173#if 1 174 /* 175 * XXX: Is this really a good idea? 176 * XXX: Should go elsewhere! -gwr 177 */ 178 zs_iflush(cs); /* XXX */ 179#endif 180 181 if (cs->cs_ctl_chan != NULL) 182 v = ((cs->cs_ctl_chan->cs_creg[5] & (ZSWR5_RTS | ZSWR5_DTR)) != 183 (cs->cs_ctl_chan->cs_preg[5] & (ZSWR5_RTS | ZSWR5_DTR))); 184 else 185 v = 0; 186 187 if (memcmp((void *)cs->cs_preg, (void *)cs->cs_creg, 16) == 0 && !v) 188 return; /* only change if values are different */ 189 190 /* Copy "pending" regs to "current" */ 191 memcpy((void *)cs->cs_creg, (void *)cs->cs_preg, 16); 192 reg = cs->cs_creg; /* current regs */ 193 194 /* disable interrupts */ 195 zs_write_reg(cs, 1, reg[1] & ~ZSWR1_IMASK); 196 197 /* baud clock divisor, stop bits, parity */ 198 zs_write_reg(cs, 4, reg[4]); 199 200 /* misc. TX/RX control bits */ 201 zs_write_reg(cs, 10, reg[10]); 202 203 /* char size, enable (RX/TX) */ 204 zs_write_reg(cs, 3, reg[3] & ~ZSWR3_RX_ENABLE); 205 zs_write_reg(cs, 5, reg[5] & ~ZSWR5_TX_ENABLE); 206 207 /* synchronous mode stuff */ 208 zs_write_reg(cs, 6, reg[6]); 209 zs_write_reg(cs, 7, reg[7]); 210 211#if 0 212 /* 213 * Registers 2 and 9 are special because they are 214 * actually common to both channels, but must be 215 * programmed through channel A. The "zsc" attach 216 * function takes care of setting these registers 217 * and they should not be touched thereafter. 218 */ 219 /* interrupt vector */ 220 zs_write_reg(cs, 2, reg[2]); 221 /* master interrupt control */ 222 zs_write_reg(cs, 9, reg[9]); 223#endif 224 225 /* Shut down the BRG */ 226 zs_write_reg(cs, 14, reg[14] & ~ZSWR14_BAUD_ENA); 227 228#ifdef ZS_MD_SETCLK 229 /* Let the MD code setup any external clock. */ 230 ZS_MD_SETCLK(cs); 231#endif /* ZS_MD_SETCLK */ 232 233 /* clock mode control */ 234 zs_write_reg(cs, 11, reg[11]); 235 236 /* baud rate (lo/hi) */ 237 zs_write_reg(cs, 12, reg[12]); 238 zs_write_reg(cs, 13, reg[13]); 239 240 /* Misc. control bits */ 241 zs_write_reg(cs, 14, reg[14]); 242 243 /* which lines cause status interrupts */ 244 zs_write_reg(cs, 15, reg[15]); 245 246 /* 247 * Zilog docs recommend resetting external status twice at this 248 * point. Mainly as the status bits are latched, and the first 249 * interrupt clear might unlatch them to new values, generating 250 * a second interrupt request. 251 */ 252 zs_write_csr(cs, ZSM_RESET_STINT); 253 zs_write_csr(cs, ZSM_RESET_STINT); 254 255 /* char size, enable (RX/TX)*/ 256 zs_write_reg(cs, 3, reg[3]); 257 zs_write_reg(cs, 5, reg[5]); 258 259 /* Write the status bits on the alternate channel also. */ 260 if (cs->cs_ctl_chan != NULL) { 261 v = cs->cs_ctl_chan->cs_preg[5]; 262 cs->cs_ctl_chan->cs_creg[5] = v; 263 zs_write_reg(cs->cs_ctl_chan, 5, v); 264 } 265 266 /* interrupt enables: RX, TX, STATUS */ 267 zs_write_reg(cs, 1, reg[1]); 268} 269 270void 271zs_lock_init(struct zs_chanstate *cs) 272{ 273 274 mutex_init(&cs->cs_lock, MUTEX_NODEBUG, IPL_ZS); 275} 276 277void 278zs_lock_chan(struct zs_chanstate *cs) 279{ 280 281 mutex_spin_enter(&cs->cs_lock); 282} 283 284void 285zs_unlock_chan(struct zs_chanstate *cs) 286{ 287 288 mutex_spin_exit(&cs->cs_lock); 289} 290 291/* 292 * ZS hardware interrupt. Scan all ZS channels. NB: we know here that 293 * channels are kept in (A,B) pairs. 294 * 295 * Do just a little, then get out; set a software interrupt if more 296 * work is needed. 297 * 298 * We deliberately ignore the vectoring Zilog gives us, and match up 299 * only the number of `reset interrupt under service' operations, not 300 * the order. 301 */ 302int 303zsc_intr_hard(void *arg) 304{ 305 struct zsc_softc *zsc = arg; 306 struct zs_chanstate *cs0, *cs1; 307 int handled; 308 uint8_t rr3; 309 310 handled = 0; 311 312 /* First look at channel A. */ 313 cs0 = zsc->zsc_cs[0]; 314 cs1 = zsc->zsc_cs[1]; 315 316 /* 317 * We have to clear interrupt first to avoid a race condition, 318 * but it will be done in each MD handler. 319 */ 320 for (;;) { 321 /* Lock both channels */ 322 mutex_spin_enter(&cs1->cs_lock); 323 mutex_spin_enter(&cs0->cs_lock); 324 /* Note: only channel A has an RR3 */ 325 rr3 = zs_read_reg(cs0, 3); 326 327 if ((rr3 & (ZSRR3_IP_A_RX | ZSRR3_IP_A_TX | ZSRR3_IP_A_STAT | 328 ZSRR3_IP_B_RX | ZSRR3_IP_B_TX | ZSRR3_IP_B_STAT)) == 0) { 329 mutex_spin_exit(&cs0->cs_lock); 330 mutex_spin_exit(&cs1->cs_lock); 331 break; 332 } 333 handled = 1; 334 335 /* First look at channel A. */ 336 if (rr3 & (ZSRR3_IP_A_RX | ZSRR3_IP_A_TX | ZSRR3_IP_A_STAT)) 337 zs_write_csr(cs0, ZSWR0_CLR_INTR); 338 339 if (rr3 & ZSRR3_IP_A_RX) 340 (*cs0->cs_ops->zsop_rxint)(cs0); 341 if (rr3 & ZSRR3_IP_A_STAT) 342 (*cs0->cs_ops->zsop_stint)(cs0, 0); 343 if (rr3 & ZSRR3_IP_A_TX) 344 (*cs0->cs_ops->zsop_txint)(cs0); 345 346 /* Done with channel A */ 347 mutex_spin_exit(&cs0->cs_lock); 348 349 /* Now look at channel B. */ 350 if (rr3 & (ZSRR3_IP_B_RX | ZSRR3_IP_B_TX | ZSRR3_IP_B_STAT)) 351 zs_write_csr(cs1, ZSWR0_CLR_INTR); 352 353 if (rr3 & ZSRR3_IP_B_RX) 354 (*cs1->cs_ops->zsop_rxint)(cs1); 355 if (rr3 & ZSRR3_IP_B_STAT) 356 (*cs1->cs_ops->zsop_stint)(cs1, 0); 357 if (rr3 & ZSRR3_IP_B_TX) 358 (*cs1->cs_ops->zsop_txint)(cs1); 359 360 mutex_spin_exit(&cs1->cs_lock); 361 } 362 363 /* Note: caller will check cs_x->cs_softreq and DTRT. */ 364 return handled; 365} 366 367 368/* 369 * ZS software interrupt. Scan all channels for deferred interrupts. 370 */ 371int 372zsc_intr_soft(void *arg) 373{ 374 struct zsc_softc *zsc = arg; 375 struct zs_chanstate *cs; 376 int rval, chan; 377 378 rval = 0; 379 for (chan = 0; chan < 2; chan++) { 380 cs = zsc->zsc_cs[chan]; 381 382 /* 383 * The softint flag can be safely cleared once 384 * we have decided to call the softint routine. 385 * (No need to do splzs() first.) 386 */ 387 if (cs->cs_softreq) { 388 cs->cs_softreq = 0; 389 (*cs->cs_ops->zsop_softint)(cs); 390 rval++; 391 } 392 } 393 return (rval); 394} 395 396/* 397 * Provide a null zs "ops" vector. 398 */ 399 400static void zsnull_rxint (struct zs_chanstate *); 401static void zsnull_stint (struct zs_chanstate *, int); 402static void zsnull_txint (struct zs_chanstate *); 403static void zsnull_softint(struct zs_chanstate *); 404 405static void 406zsnull_rxint(struct zs_chanstate *cs) 407{ 408 409 /* Ask for softint() call. */ 410 cs->cs_softreq = 1; 411} 412 413static void 414zsnull_stint(struct zs_chanstate *cs, int force) 415{ 416 417 /* Ask for softint() call. */ 418 cs->cs_softreq = 1; 419} 420 421static void 422zsnull_txint(struct zs_chanstate *cs) 423{ 424 425 /* Ask for softint() call. */ 426 cs->cs_softreq = 1; 427} 428 429static void 430zsnull_softint(struct zs_chanstate *cs) 431{ 432 433 zs_write_reg(cs, 1, 0); 434 zs_write_reg(cs, 15, 0); 435} 436 437struct zsops zsops_null = { 438 zsnull_rxint, /* receive char available */ 439 zsnull_stint, /* external/status */ 440 zsnull_txint, /* xmit buffer empty */ 441 zsnull_softint, /* process software interrupt */ 442}; 443