Annotation of sys/arch/mac68k/dev/z8530sc.c, Revision 1.1
1.1 ! nbrk 1: /* $OpenBSD: z8530sc.c,v 1.7 2004/11/25 18:32:10 miod Exp $ */
! 2: /* $NetBSD: z8530sc.c,v 1.5 1996/12/17 20:42:40 gwr Exp $ */
! 3:
! 4: /*
! 5: * Copyright (c) 1994 Gordon W. Ross
! 6: * Copyright (c) 1992, 1993
! 7: * The Regents of the University of California. All rights reserved.
! 8: *
! 9: * This software was developed by the Computer Systems Engineering group
! 10: * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
! 11: * contributed to Berkeley.
! 12: *
! 13: * All advertising materials mentioning features or use of this software
! 14: * must display the following acknowledgement:
! 15: * This product includes software developed by the University of
! 16: * California, Lawrence Berkeley Laboratory.
! 17: *
! 18: * Redistribution and use in source and binary forms, with or without
! 19: * modification, are permitted provided that the following conditions
! 20: * are met:
! 21: * 1. Redistributions of source code must retain the above copyright
! 22: * notice, this list of conditions and the following disclaimer.
! 23: * 2. Redistributions in binary form must reproduce the above copyright
! 24: * notice, this list of conditions and the following disclaimer in the
! 25: * documentation and/or other materials provided with the distribution.
! 26: * 3. Neither the name of the University nor the names of its contributors
! 27: * may be used to endorse or promote products derived from this software
! 28: * without specific prior written permission.
! 29: *
! 30: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
! 31: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
! 32: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
! 33: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
! 34: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
! 35: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
! 36: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
! 37: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
! 38: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
! 39: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
! 40: * SUCH DAMAGE.
! 41: *
! 42: * @(#)zs.c 8.1 (Berkeley) 7/19/93
! 43: */
! 44:
! 45: /*
! 46: * Zilog Z8530 Dual UART driver (common part)
! 47: *
! 48: * This file contains the machine-independent parts of the
! 49: * driver common to tty and keyboard/mouse sub-drivers.
! 50: */
! 51:
! 52: #include <sys/param.h>
! 53: #include <sys/systm.h>
! 54: #include <sys/proc.h>
! 55: #include <sys/device.h>
! 56: #include <sys/conf.h>
! 57: #include <sys/file.h>
! 58: #include <sys/ioctl.h>
! 59: #include <sys/tty.h>
! 60: #include <sys/time.h>
! 61: #include <sys/kernel.h>
! 62: #include <sys/syslog.h>
! 63:
! 64: #include <mac68k/dev/z8530reg.h>
! 65: #include <machine/z8530var.h>
! 66:
! 67: static void zsnull_intr(struct zs_chanstate *);
! 68: static void zsnull_softint(struct zs_chanstate *);
! 69:
! 70: void
! 71: zs_break(cs, set)
! 72: struct zs_chanstate *cs;
! 73: int set;
! 74: {
! 75: int s;
! 76:
! 77: s = splzs();
! 78: if (set) {
! 79: cs->cs_preg[5] |= ZSWR5_BREAK;
! 80: cs->cs_creg[5] |= ZSWR5_BREAK;
! 81: } else {
! 82: cs->cs_preg[5] &= ~ZSWR5_BREAK;
! 83: cs->cs_creg[5] &= ~ZSWR5_BREAK;
! 84: }
! 85: zs_write_reg(cs, 5, cs->cs_creg[5]);
! 86: splx(s);
! 87: }
! 88:
! 89:
! 90: /*
! 91: * drain on-chip fifo
! 92: */
! 93: void
! 94: zs_iflush(cs)
! 95: struct zs_chanstate *cs;
! 96: {
! 97: u_char c, rr0, rr1;
! 98:
! 99: for (;;) {
! 100: /* Is there input available? */
! 101: rr0 = zs_read_csr(cs);
! 102: if ((rr0 & ZSRR0_RX_READY) == 0)
! 103: break;
! 104:
! 105: /*
! 106: * First read the status, because reading the data
! 107: * destroys the status of this char.
! 108: */
! 109: rr1 = zs_read_reg(cs, 1);
! 110: c = zs_read_data(cs);
! 111:
! 112: if (rr1 & (ZSRR1_FE | ZSRR1_DO | ZSRR1_PE)) {
! 113: /* Clear the receive error. */
! 114: zs_write_csr(cs, ZSWR0_RESET_ERRORS);
! 115: }
! 116: }
! 117: }
! 118:
! 119:
! 120: /*
! 121: * Write the given register set to the given zs channel in the proper order.
! 122: * The channel must not be transmitting at the time. The receiver will
! 123: * be disabled for the time it takes to write all the registers.
! 124: * Call this with interrupts disabled.
! 125: */
! 126: void
! 127: zs_loadchannelregs(cs)
! 128: struct zs_chanstate *cs;
! 129: {
! 130: u_char *reg;
! 131:
! 132: /* Copy "pending" regs to "current" */
! 133: bcopy((caddr_t)cs->cs_preg, (caddr_t)cs->cs_creg, 16);
! 134: reg = cs->cs_creg; /* current regs */
! 135:
! 136: zs_write_csr(cs, ZSM_RESET_ERR); /* XXX: reset error condition */
! 137:
! 138: #if 1
! 139: /*
! 140: * XXX: Is this really a good idea?
! 141: * XXX: Should go elsewhere! -gwr
! 142: */
! 143: zs_iflush(cs); /* XXX */
! 144: #endif
! 145:
! 146: /* disable interrupts */
! 147: zs_write_reg(cs, 1, reg[1] & ~ZSWR1_IMASK);
! 148:
! 149: /* baud clock divisor, stop bits, parity */
! 150: zs_write_reg(cs, 4, reg[4]);
! 151:
! 152: /* misc. TX/RX control bits */
! 153: zs_write_reg(cs, 10, reg[10]);
! 154:
! 155: /* char size, enable (RX/TX) */
! 156: zs_write_reg(cs, 3, reg[3] & ~ZSWR3_RX_ENABLE);
! 157: zs_write_reg(cs, 5, reg[5] & ~ZSWR5_TX_ENABLE);
! 158:
! 159: /* synchronous mode stuff */
! 160: zs_write_reg(cs, 6, reg[6]);
! 161: zs_write_reg(cs, 7, reg[7]);
! 162:
! 163: #if 0
! 164: /*
! 165: * Registers 2 and 9 are special because they are
! 166: * actually common to both channels, but must be
! 167: * programmed through channel A. The "zsc" attach
! 168: * function takes care of setting these registers
! 169: * and they should not be touched thereafter.
! 170: */
! 171: /* interrupt vector */
! 172: zs_write_reg(cs, 2, reg[2]);
! 173: /* master interrupt control */
! 174: zs_write_reg(cs, 9, reg[9]);
! 175: #endif
! 176:
! 177: /* Shut down the BRG */
! 178: zs_write_reg(cs, 14, reg[14] & ~ZSWR14_BAUD_ENA);
! 179:
! 180: #ifdef ZS_MD_SETCLK
! 181: /* Let the MD code setup any external clock. */
! 182: ZS_MD_SETCLK(cs);
! 183: #endif /* ZS_MD_SETCLK */
! 184:
! 185: /* clock mode control */
! 186: zs_write_reg(cs, 11, reg[11]);
! 187:
! 188: /* baud rate (lo/hi) */
! 189: zs_write_reg(cs, 12, reg[12]);
! 190: zs_write_reg(cs, 13, reg[13]);
! 191:
! 192: /* Misc. control bits */
! 193: zs_write_reg(cs, 14, reg[14]);
! 194:
! 195: /* which lines cause status interrupts */
! 196: zs_write_reg(cs, 15, reg[15]);
! 197:
! 198: /*
! 199: * Zilog docs recommend resetting external status twice at this
! 200: * point. Mainly as the status bits are latched, and the first
! 201: * interrupt clear might unlatch them to new values, generating
! 202: * a second interrupt request.
! 203: */
! 204: zs_write_csr(cs, ZSM_RESET_STINT);
! 205: zs_write_csr(cs, ZSM_RESET_STINT);
! 206:
! 207: /* char size, enable (RX/TX)*/
! 208: zs_write_reg(cs, 3, reg[3]);
! 209: zs_write_reg(cs, 5, reg[5]);
! 210:
! 211: /* interrupt enables: RX, TX, STATUS */
! 212: zs_write_reg(cs, 1, reg[1]);
! 213: }
! 214:
! 215:
! 216: /*
! 217: * ZS hardware interrupt. Scan all ZS channels. NB: we know here that
! 218: * channels are kept in (A,B) pairs.
! 219: *
! 220: * Do just a little, then get out; set a software interrupt if more
! 221: * work is needed.
! 222: *
! 223: * We deliberately ignore the vectoring Zilog gives us, and match up
! 224: * only the number of `reset interrupt under service' operations, not
! 225: * the order.
! 226: */
! 227: int
! 228: zsc_intr_hard(arg)
! 229: void *arg;
! 230: {
! 231: register struct zsc_softc *zsc = arg;
! 232: register struct zs_chanstate *cs_a;
! 233: register struct zs_chanstate *cs_b;
! 234: register int rval;
! 235: register u_char rr3, rr3a;
! 236:
! 237: cs_a = zsc->zsc_cs[0];
! 238: cs_b = zsc->zsc_cs[1];
! 239: rval = 0;
! 240: rr3a = 0;
! 241:
! 242: /* Note: only channel A has an RR3 */
! 243: while ((rr3 = zs_read_reg(cs_a, 3)) != 0) {
! 244:
! 245: /* Handle receive interrupts first. */
! 246: if (rr3 & ZSRR3_IP_A_RX)
! 247: (*cs_a->cs_ops->zsop_rxint)(cs_a);
! 248: if (rr3 & ZSRR3_IP_B_RX)
! 249: (*cs_b->cs_ops->zsop_stint)(cs_b);
! 250:
! 251: /* Handle status interrupts (i.e. flow control). */
! 252: if (rr3 & ZSRR3_IP_A_STAT)
! 253: (*cs_a->cs_ops->zsop_stint)(cs_a);
! 254: if (rr3 & ZSRR3_IP_B_STAT)
! 255: (*cs_b->cs_ops->zsop_stint)(cs_b);
! 256:
! 257: /* Handle transmit done interrupts. */
! 258: if (rr3 & ZSRR3_IP_A_TX)
! 259: (*cs_a->cs_ops->zsop_txint)(cs_a);
! 260: if (rr3 & ZSRR3_IP_B_TX)
! 261: (*cs_b->cs_ops->zsop_txint)(cs_b);
! 262:
! 263: /* Accumulate so we know what needs to be cleared. */
! 264: rr3a |= rr3;
! 265: }
! 266:
! 267:
! 268: /* Clear interrupt. */
! 269: if (rr3a & (ZSRR3_IP_A_RX | ZSRR3_IP_A_TX | ZSRR3_IP_A_STAT)) {
! 270: zs_write_csr(cs_a, ZSWR0_CLR_INTR);
! 271: rval |= 1;
! 272: }
! 273: if (rr3a & (ZSRR3_IP_B_RX | ZSRR3_IP_B_TX | ZSRR3_IP_B_STAT)) {
! 274: zs_write_csr(cs_b, ZSWR0_CLR_INTR);
! 275: rval |= 2;
! 276: }
! 277:
! 278: /* Note: caller will check cs_x->cs_softreq and DTRT. */
! 279: return (rval);
! 280: }
! 281:
! 282:
! 283: /*
! 284: * ZS software interrupt. Scan all channels for deferred interrupts.
! 285: */
! 286: int
! 287: zsc_intr_soft(arg)
! 288: void *arg;
! 289: {
! 290: register struct zsc_softc *zsc = arg;
! 291: register struct zs_chanstate *cs;
! 292: register int rval, chan;
! 293:
! 294: rval = 0;
! 295: for (chan = 0; chan < 2; chan++) {
! 296: cs = zsc->zsc_cs[chan];
! 297:
! 298: /*
! 299: * The softint flag can be safely cleared once
! 300: * we have decided to call the softint routine.
! 301: * (No need to do splzs() first.)
! 302: */
! 303: if (cs->cs_softreq) {
! 304: cs->cs_softreq = 0;
! 305: (*cs->cs_ops->zsop_softint)(cs);
! 306: rval++;
! 307: }
! 308: }
! 309: return (rval);
! 310: }
! 311:
! 312: /*
! 313: * Provide a null zs "ops" vector.
! 314: */
! 315:
! 316: static void zsnull_intr(struct zs_chanstate *);
! 317: static void zsnull_softint(struct zs_chanstate *);
! 318:
! 319: static void
! 320: zsnull_intr(cs)
! 321: struct zs_chanstate *cs;
! 322: {
! 323: /* Ask for softint() call. */
! 324: cs->cs_softreq = 1;
! 325: }
! 326:
! 327: static void
! 328: zsnull_softint(cs)
! 329: struct zs_chanstate *cs;
! 330: {
! 331: zs_write_reg(cs, 1, 0);
! 332: zs_write_reg(cs, 15, 0);
! 333: }
! 334:
! 335: struct zsops zsops_null = {
! 336: zsnull_intr, /* receive char available */
! 337: zsnull_intr, /* external/status */
! 338: zsnull_intr, /* xmit buffer empty */
! 339: zsnull_softint, /* process software interrupt */
! 340: };
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