bcm2835_mbox.c revision 1.3
1 /* $NetBSD: bcm2835_mbox.c,v 1.3 2013/01/07 20:15:32 jmcneill 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 1.3 2013/01/07 20:15:32 jmcneill 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 42 #include <arm/broadcom/bcm_amba.h> 43 #include <arm/broadcom/bcm2835_mbox.h> 44 #include <arm/broadcom/bcm2835_mboxreg.h> 45 #include <arm/broadcom/bcm2835reg.h> 46 47 struct bcm2835mbox_softc { 48 device_t sc_dev; 49 device_t sc_platdev; 50 51 bus_space_tag_t sc_iot; 52 bus_space_handle_t sc_ioh; 53 bus_dma_tag_t sc_dmat; 54 }; 55 56 static struct bcm2835mbox_softc *bcm2835mbox_sc; 57 58 static int bcmmbox_match(device_t, cfdata_t, void *); 59 static void bcmmbox_attach(device_t, device_t, void *); 60 61 CFATTACH_DECL_NEW(bcmmbox, sizeof(struct bcm2835mbox_softc), 62 bcmmbox_match, bcmmbox_attach, NULL, NULL); 63 64 /* ARGSUSED */ 65 static int 66 bcmmbox_match(device_t parent, cfdata_t match, void *aux) 67 { 68 struct amba_attach_args *aaa = aux; 69 70 if (strcmp(aaa->aaa_name, "bcmmbox") != 0) 71 return 0; 72 73 return 1; 74 } 75 76 static void 77 bcmmbox_attach(device_t parent, device_t self, void *aux) 78 { 79 struct bcm2835mbox_softc *sc = device_private(self); 80 struct amba_attach_args *aaa = aux; 81 struct bcmmbox_attach_args baa; 82 83 aprint_naive("\n"); 84 aprint_normal(": VC mailbox\n"); 85 86 if (bcm2835mbox_sc == NULL) 87 bcm2835mbox_sc = sc; 88 89 sc->sc_dev = self; 90 sc->sc_iot = aaa->aaa_iot; 91 sc->sc_dmat = aaa->aaa_dmat; 92 93 if (bus_space_map(aaa->aaa_iot, aaa->aaa_addr, BCM2835_MBOX_SIZE, 0, 94 &sc->sc_ioh)) { 95 aprint_error_dev(sc->sc_dev, "unable to map device\n"); 96 return; 97 } 98 99 baa.baa_dmat = aaa->aaa_dmat; 100 sc->sc_platdev = config_found_ia(self, "bcmmboxbus", &baa, NULL); 101 } 102 103 void 104 bcmmbox_read(uint8_t chan, uint32_t *data) 105 { 106 struct bcm2835mbox_softc *sc = bcm2835mbox_sc; 107 108 KASSERT(sc != NULL); 109 110 return bcm2835_mbox_read(sc->sc_iot, sc->sc_ioh, chan, data); 111 } 112 113 void 114 bcmmbox_write(uint8_t chan, uint32_t data) 115 { 116 struct bcm2835mbox_softc *sc = bcm2835mbox_sc; 117 118 KASSERT(sc != NULL); 119 120 return bcm2835_mbox_write(sc->sc_iot, sc->sc_ioh, chan, data); 121 } 122 123 int 124 bcmmbox_request(uint8_t chan, void *buf, size_t buflen, uint32_t *pres) 125 { 126 struct bcm2835mbox_softc *sc = bcm2835mbox_sc; 127 void *dma_buf; 128 bus_dmamap_t map; 129 bus_dma_segment_t segs[1]; 130 int nsegs; 131 int error; 132 133 KASSERT(sc != NULL); 134 135 error = bus_dmamem_alloc(sc->sc_dmat, buflen, 16, 0, segs, 1, 136 &nsegs, BUS_DMA_WAITOK); 137 if (error) 138 return error; 139 error = bus_dmamem_map(sc->sc_dmat, segs, nsegs, buflen, &dma_buf, 140 BUS_DMA_WAITOK); 141 if (error) 142 goto map_failed; 143 error = bus_dmamap_create(sc->sc_dmat, buflen, 1, buflen, 0, 144 BUS_DMA_WAITOK, &map); 145 if (error) 146 goto create_failed; 147 error = bus_dmamap_load(sc->sc_dmat, map, dma_buf, buflen, NULL, 148 BUS_DMA_WAITOK); 149 if (error) 150 goto load_failed; 151 152 memcpy(dma_buf, buf, buflen); 153 154 bus_dmamap_sync(sc->sc_dmat, map, 0, buflen, BUS_DMASYNC_PREWRITE); 155 bcmmbox_write(chan, map->dm_segs[0].ds_addr); 156 bus_dmamap_sync(sc->sc_dmat, map, 0, buflen, BUS_DMASYNC_POSTWRITE); 157 bus_dmamap_sync(sc->sc_dmat, map, 0, buflen, BUS_DMASYNC_PREREAD); 158 bcmmbox_read(chan, pres); 159 160 memcpy(buf, dma_buf, buflen); 161 162 bus_dmamap_unload(sc->sc_dmat, map); 163 load_failed: 164 bus_dmamap_destroy(sc->sc_dmat, map); 165 create_failed: 166 bus_dmamem_unmap(sc->sc_dmat, dma_buf, buflen); 167 map_failed: 168 bus_dmamem_free(sc->sc_dmat, segs, nsegs); 169 return error; 170 } 171
Indexes created Mon Sep 29 13:09:55 GMT 2025