rambo.c revision 1.10
1 /* $NetBSD: rambo.c,v 1.10 2009/03/14 14:46:02 dsl 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 * 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 #include <sys/cdefs.h> 33 __KERNEL_RCSID(0, "$NetBSD: rambo.c,v 1.10 2009/03/14 14:46:02 dsl Exp $"); 34 35 #include <sys/param.h> 36 #include <sys/kernel.h> 37 #include <sys/device.h> 38 #include <sys/systm.h> 39 #include <sys/timetc.h> 40 41 #include <machine/cpu.h> 42 #include <machine/mainboard.h> 43 #include <machine/autoconf.h> 44 #include <machine/sysconf.h> 45 #include <machine/bus.h> 46 47 #include <mipsco/obio/rambo.h> 48 49 /* 50 * Timer & Interrupt manipulation routines for the Rambo Custom ASIC 51 */ 52 53 static int rambo_match(struct device *, struct cfdata *, void *); 54 static void rambo_attach(struct device *, struct device *, void *); 55 static unsigned rambo_get_timecount(struct timecounter *); 56 void rambo_clkintr(struct clockframe *); 57 static void rambo_tc_init(void); 58 59 struct rambo_softc { 60 struct device dev; 61 struct evcnt sc_intrcnt; 62 bus_space_tag_t sc_bst; 63 bus_space_handle_t sc_bsh; 64 u_int32_t sc_tclast; 65 u_int32_t sc_hzticks; 66 }; 67 68 static struct rambo_softc *rambo; 69 70 CFATTACH_DECL(rambo, sizeof(struct rambo_softc), 71 rambo_match, rambo_attach, NULL, NULL); 72 73 static int 74 rambo_match(parent, cf, aux) 75 struct device *parent; 76 struct cfdata *cf; 77 void *aux; 78 { 79 return 1; 80 } 81 82 static void 83 rambo_attach(parent, self, aux) 84 struct device *parent, *self; 85 void *aux; 86 { 87 struct confargs *ca = aux; 88 struct rambo_softc *sc = (void *)self; 89 90 sc->sc_bst = ca->ca_bustag; 91 92 if (bus_space_map(ca->ca_bustag, ca->ca_addr, 256, 93 BUS_SPACE_MAP_LINEAR, 94 &sc->sc_bsh) != 0) { 95 printf(": cannot map registers\n"); 96 return; 97 } 98 evcnt_attach_dynamic(&sc->sc_intrcnt, EVCNT_TYPE_INTR, NULL, 99 "timer", "intr"); 100 101 /* Setup RAMBO Timer to generate timer interrupts */ 102 sc->sc_hzticks = HZ_TO_TICKS(hz); 103 104 sc->sc_tclast = 0; 105 bus_space_write_4(sc->sc_bst, sc->sc_bsh, RB_TCOUNT, 0); 106 bus_space_write_4(sc->sc_bst, sc->sc_bsh, RB_TBREAK, sc->sc_hzticks); 107 108 bus_space_write_4(sc->sc_bst, sc->sc_bsh, RB_CTLREG, 109 RB_PARITY_EN | RB_BUZZOFF | RB_CLR_IOERR); 110 111 printf(": parity enabled\n"); 112 rambo = sc; 113 platform.clkinit = rambo_tc_init; 114 } 115 116 void 117 rambo_clkintr(cf) 118 struct clockframe *cf; 119 { 120 register u_int32_t tbreak, tcount; 121 register int delta; 122 123 rambo->sc_intrcnt.ev_count++; 124 tbreak = bus_space_read_4(rambo->sc_bst, rambo->sc_bsh, RB_TBREAK); 125 tcount = bus_space_read_4(rambo->sc_bst, rambo->sc_bsh, RB_TCOUNT); 126 delta = tcount - tbreak; 127 128 if (delta > (rambo->sc_hzticks>>1)) { 129 /* 130 * Either tcount may overtake the updated tbreak value 131 * or we have missed several interrupt's 132 */ 133 int cycles = 10 * hz; 134 while (cycles && tbreak < tcount) { 135 hardclock(cf); 136 rambo->sc_tclast = tbreak; 137 tbreak += rambo->sc_hzticks; 138 cycles--; 139 } 140 if (cycles == 0) { /* catchup failed - assume we are in sync */ 141 tcount = bus_space_read_4(rambo->sc_bst, 142 rambo->sc_bsh, RB_TCOUNT); 143 rambo->sc_tclast = tbreak = tcount; 144 } 145 } else { 146 hardclock(cf); 147 rambo->sc_tclast = tbreak; 148 } 149 150 tbreak += rambo->sc_hzticks; 151 152 bus_space_write_4(rambo->sc_bst, rambo->sc_bsh, RB_TBREAK, tbreak); 153 } 154 155 /* 156 * Calculate the number of microseconds since the last clock tick 157 */ 158 static unsigned 159 rambo_get_timecount(struct timecounter *tc) 160 { 161 162 return (bus_space_read_4(rambo->sc_bst, rambo->sc_bsh, RB_TCOUNT)); 163 } 164 165 static void 166 rambo_tc_init(void) 167 { 168 static struct timecounter tc = { 169 .tc_get_timecount = rambo_get_timecount, 170 .tc_frequency = RB_FREQUENCY, 171 .tc_quality = 100, 172 .tc_name = "rambo_tcount", 173 .tc_counter_mask = ~0 174 }; 175 176 tc_init(&tc); 177 } 178
Indexes created Mon Sep 29 21:09:56 GMT 2025