rambo.c revision 1.8
1 /* $NetBSD: rambo.c,v 1.8 2006/09/15 16:37:19 gdamore Exp $ */ 2 3 /* 4 * Copyright (c) 2000 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by 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 #include <sys/cdefs.h> 40 __KERNEL_RCSID(0, "$NetBSD: rambo.c,v 1.8 2006/09/15 16:37:19 gdamore Exp $"); 41 42 #include <sys/param.h> 43 #include <sys/kernel.h> 44 #include <sys/device.h> 45 #include <sys/systm.h> 46 #include <sys/timetc.h> 47 48 #include <machine/cpu.h> 49 #include <machine/mainboard.h> 50 #include <machine/autoconf.h> 51 #include <machine/sysconf.h> 52 #include <machine/bus.h> 53 54 #include <mipsco/obio/rambo.h> 55 56 /* 57 * Timer & Interrupt manipulation routines for the Rambo Custom ASIC 58 */ 59 60 static int rambo_match __P((struct device *, struct cfdata *, void *)); 61 static void rambo_attach __P((struct device *, struct device *, void *)); 62 static unsigned rambo_get_timecount(struct timecounter *); 63 void rambo_clkintr __P((struct clockframe *)); 64 static void rambo_tc_init(void); 65 66 struct rambo_softc { 67 struct device dev; 68 struct evcnt sc_intrcnt; 69 bus_space_tag_t sc_bst; 70 bus_space_handle_t sc_bsh; 71 u_int32_t sc_tclast; 72 u_int32_t sc_hzticks; 73 }; 74 75 static struct rambo_softc *rambo; 76 77 CFATTACH_DECL(rambo, sizeof(struct rambo_softc), 78 rambo_match, rambo_attach, NULL, NULL); 79 80 static int 81 rambo_match(parent, cf, aux) 82 struct device *parent; 83 struct cfdata *cf; 84 void *aux; 85 { 86 return 1; 87 } 88 89 static void 90 rambo_attach(parent, self, aux) 91 struct device *parent, *self; 92 void *aux; 93 { 94 struct confargs *ca = aux; 95 struct rambo_softc *sc = (void *)self; 96 97 sc->sc_bst = ca->ca_bustag; 98 99 if (bus_space_map(ca->ca_bustag, ca->ca_addr, 256, 100 BUS_SPACE_MAP_LINEAR, 101 &sc->sc_bsh) != 0) { 102 printf(": cannot map registers\n"); 103 return; 104 } 105 evcnt_attach_dynamic(&sc->sc_intrcnt, EVCNT_TYPE_INTR, NULL, 106 "timer", "intr"); 107 108 /* Setup RAMBO Timer to generate timer interrupts */ 109 sc->sc_hzticks = HZ_TO_TICKS(hz); 110 111 sc->sc_tclast = 0; 112 bus_space_write_4(sc->sc_bst, sc->sc_bsh, RB_TCOUNT, 0); 113 bus_space_write_4(sc->sc_bst, sc->sc_bsh, RB_TBREAK, sc->sc_hzticks); 114 115 bus_space_write_4(sc->sc_bst, sc->sc_bsh, RB_CTLREG, 116 RB_PARITY_EN | RB_BUZZOFF | RB_CLR_IOERR); 117 118 printf(": parity enabled\n"); 119 rambo = sc; 120 platform.clkinit = rambo_tc_init; 121 } 122 123 void 124 rambo_clkintr(cf) 125 struct clockframe *cf; 126 { 127 register u_int32_t tbreak, tcount; 128 register int delta; 129 130 rambo->sc_intrcnt.ev_count++; 131 tbreak = bus_space_read_4(rambo->sc_bst, rambo->sc_bsh, RB_TBREAK); 132 tcount = bus_space_read_4(rambo->sc_bst, rambo->sc_bsh, RB_TCOUNT); 133 delta = tcount - tbreak; 134 135 if (delta > (rambo->sc_hzticks>>1)) { 136 /* 137 * Either tcount may overtake the updated tbreak value 138 * or we have missed several interrupt's 139 */ 140 int cycles = 10 * hz; 141 while (cycles && tbreak < tcount) { 142 hardclock(cf); 143 rambo->sc_tclast = tbreak; 144 tbreak += rambo->sc_hzticks; 145 cycles--; 146 } 147 if (cycles == 0) { /* catchup failed - assume we are in sync */ 148 tcount = bus_space_read_4(rambo->sc_bst, 149 rambo->sc_bsh, RB_TCOUNT); 150 rambo->sc_tclast = tbreak = tcount; 151 } 152 } else { 153 hardclock(cf); 154 rambo->sc_tclast = tbreak; 155 } 156 157 tbreak += rambo->sc_hzticks; 158 159 bus_space_write_4(rambo->sc_bst, rambo->sc_bsh, RB_TBREAK, tbreak); 160 } 161 162 /* 163 * Calculate the number of microseconds since the last clock tick 164 */ 165 static unsigned 166 rambo_get_timecount(struct timecounter *tc) 167 { 168 169 return (bus_space_read_4(rambo->sc_bst, rambo->sc_bsh, RB_TCOUNT)); 170 } 171 172 static void 173 rambo_tc_init(void) 174 { 175 static struct timecounter tc = { 176 .tc_get_timecount = rambo_get_timecount, 177 .tc_frequency = RB_FREQUENCY, 178 .tc_quality = 100, 179 .tc_name = "rambo_tcount", 180 .tc_counter_mask = ~0 181 }; 182 183 tc_init(&tc); 184 } 185
Indexes created Mon Sep 29 21:09:56 GMT 2025