bcm2835_mbox.c revision 1.5
1 /* $NetBSD: bcm2835_mbox.c,v 1.5 2013/01/08 12:15:42 skrll Exp $ */ 2 3 /*- 4 * Copyright (c) 2012 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Nick Hudson 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: bcm2835_mbox.c,v 1.5 2013/01/08 12:15:42 skrll Exp $"); 34 35 #include <sys/param.h> 36 #include <sys/systm.h> 37 #include <sys/device.h> 38 #include <sys/kernel.h> 39 #include <sys/timetc.h> 40 #include <sys/bus.h> 41 #include <sys/mutex.h> 42 43 #include <arm/broadcom/bcm_amba.h> 44 #include <arm/broadcom/bcm2835_mbox.h> 45 #include <arm/broadcom/bcm2835_mboxreg.h> 46 #include <arm/broadcom/bcm2835reg.h> 47 48 struct bcm2835mbox_softc { 49 device_t sc_dev; 50 device_t sc_platdev; 51 52 bus_space_tag_t sc_iot; 53 bus_space_handle_t sc_ioh; 54 bus_dma_tag_t sc_dmat; 55 56 kmutex_t sc_lock; 57 }; 58 59 static struct bcm2835mbox_softc *bcm2835mbox_sc; 60 61 static int bcmmbox_match(device_t, cfdata_t, void *); 62 static void bcmmbox_attach(device_t, device_t, void *); 63 64 CFATTACH_DECL_NEW(bcmmbox, sizeof(struct bcm2835mbox_softc), 65 bcmmbox_match, bcmmbox_attach, NULL, NULL); 66 67 /* ARGSUSED */ 68 static int 69 bcmmbox_match(device_t parent, cfdata_t match, void *aux) 70 { 71 struct amba_attach_args *aaa = aux; 72 73 if (strcmp(aaa->aaa_name, "bcmmbox") != 0) 74 return 0; 75 76 return 1; 77 } 78 79 static void 80 bcmmbox_attach(device_t parent, device_t self, void *aux) 81 { 82 struct bcm2835mbox_softc *sc = device_private(self); 83 struct amba_attach_args *aaa = aux; 84 struct bcmmbox_attach_args baa; 85 86 aprint_naive("\n"); 87 aprint_normal(": VC mailbox\n"); 88 89 if (bcm2835mbox_sc == NULL) 90 bcm2835mbox_sc = sc; 91 92 sc->sc_dev = self; 93 sc->sc_iot = aaa->aaa_iot; 94 sc->sc_dmat = aaa->aaa_dmat; 95 mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_NONE); 96 97 if (bus_space_map(aaa->aaa_iot, aaa->aaa_addr, BCM2835_MBOX_SIZE, 0, 98 &sc->sc_ioh)) { 99 aprint_error_dev(sc->sc_dev, "unable to map device\n"); 100 return; 101 } 102 103 baa.baa_dmat = aaa->aaa_dmat; 104 sc->sc_platdev = config_found_ia(self, "bcmmboxbus", &baa, NULL); 105 } 106 107 void 108 bcmmbox_read(uint8_t chan, uint32_t *data) 109 { 110 struct bcm2835mbox_softc *sc = bcm2835mbox_sc; 111 112 KASSERT(sc != NULL); 113 114 return bcm2835_mbox_read(sc->sc_iot, sc->sc_ioh, chan, data); 115 } 116 117 void 118 bcmmbox_write(uint8_t chan, uint32_t data) 119 { 120 struct bcm2835mbox_softc *sc = bcm2835mbox_sc; 121 122 KASSERT(sc != NULL); 123 124 return bcm2835_mbox_write(sc->sc_iot, sc->sc_ioh, chan, data); 125 } 126 127 int 128 bcmmbox_request(uint8_t chan, void *buf, size_t buflen, uint32_t *pres) 129 { 130 struct bcm2835mbox_softc *sc = bcm2835mbox_sc; 131 void *dma_buf; 132 bus_dmamap_t map; 133 bus_dma_segment_t segs[1]; 134 int nsegs; 135 int error; 136 137 KASSERT(sc != NULL); 138 139 error = bus_dmamem_alloc(sc->sc_dmat, buflen, 16, 0, segs, 1, 140 &nsegs, BUS_DMA_WAITOK); 141 if (error) 142 return error; 143 error = bus_dmamem_map(sc->sc_dmat, segs, nsegs, buflen, &dma_buf, 144 BUS_DMA_WAITOK); 145 if (error) 146 goto map_failed; 147 error = bus_dmamap_create(sc->sc_dmat, buflen, 1, buflen, 0, 148 BUS_DMA_WAITOK, &map); 149 if (error) 150 goto create_failed; 151 error = bus_dmamap_load(sc->sc_dmat, map, dma_buf, buflen, NULL, 152 BUS_DMA_WAITOK); 153 if (error) 154 goto load_failed; 155 156 memcpy(dma_buf, buf, buflen); 157 158 mutex_enter(&sc->sc_lock); 159 160 bus_dmamap_sync(sc->sc_dmat, map, 0, buflen, BUS_DMASYNC_PREWRITE); 161 bcmmbox_write(chan, map->dm_segs[0].ds_addr); 162 bus_dmamap_sync(sc->sc_dmat, map, 0, buflen, BUS_DMASYNC_POSTWRITE); 163 bus_dmamap_sync(sc->sc_dmat, map, 0, buflen, BUS_DMASYNC_PREREAD); 164 bcmmbox_read(chan, pres); 165 166 mutex_exit(&sc->sc_lock); 167 168 memcpy(buf, dma_buf, buflen); 169 170 bus_dmamap_unload(sc->sc_dmat, map); 171 load_failed: 172 bus_dmamap_destroy(sc->sc_dmat, map); 173 create_failed: 174 bus_dmamem_unmap(sc->sc_dmat, dma_buf, buflen); 175 map_failed: 176 bus_dmamem_free(sc->sc_dmat, segs, nsegs); 177 178 return error; 179 } 180
Indexes created Mon Sep 29 21:09:56 GMT 2025