/* $NetBSD: bcm2835_mbox.c,v 1.11 2015/07/29 14:22:49 skrll Exp $ */ /*- * Copyright (c) 2012 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Nick Hudson * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ #include __KERNEL_RCSID(0, "$NetBSD: bcm2835_mbox.c,v 1.11 2015/07/29 14:22:49 skrll Exp $"); #include #include #include #include #include #include #include #include #include #include #include struct bcm2835mbox_softc { device_t sc_dev; device_t sc_platdev; bus_space_tag_t sc_iot; bus_space_handle_t sc_ioh; bus_dma_tag_t sc_dmat; void *sc_intrh; kmutex_t sc_lock; kmutex_t sc_intr_lock; kcondvar_t sc_chan[BCM2835_MBOX_NUMCHANNELS]; uint32_t sc_mbox[BCM2835_MBOX_NUMCHANNELS]; }; static struct bcm2835mbox_softc *bcm2835mbox_sc; static int bcmmbox_match(device_t, cfdata_t, void *); static void bcmmbox_attach(device_t, device_t, void *); static int bcmmbox_intr1(struct bcm2835mbox_softc *, int); static int bcmmbox_intr(void *); CFATTACH_DECL_NEW(bcmmbox, sizeof(struct bcm2835mbox_softc), bcmmbox_match, bcmmbox_attach, NULL, NULL); /* ARGSUSED */ static int bcmmbox_match(device_t parent, cfdata_t match, void *aux) { struct amba_attach_args *aaa = aux; if (strcmp(aaa->aaa_name, "bcmmbox") != 0) return 0; return 1; } static void bcmmbox_attach(device_t parent, device_t self, void *aux) { struct bcm2835mbox_softc *sc = device_private(self); struct amba_attach_args *aaa = aux; struct bcmmbox_attach_args baa; int i; aprint_naive("\n"); aprint_normal(": VC mailbox\n"); sc->sc_dev = self; sc->sc_iot = aaa->aaa_iot; sc->sc_dmat = aaa->aaa_dmat; mutex_init(&sc->sc_lock, MUTEX_DEFAULT, IPL_NONE); mutex_init(&sc->sc_intr_lock, MUTEX_DEFAULT, IPL_VM); for (i = 0; i < BCM2835_MBOX_NUMCHANNELS; ++i) cv_init(&sc->sc_chan[i], "bcmmbox"); if (bus_space_map(aaa->aaa_iot, aaa->aaa_addr, BCM2835_MBOX_SIZE, 0, &sc->sc_ioh)) { aprint_error_dev(sc->sc_dev, "unable to map device\n"); return; } sc->sc_intrh = intr_establish(aaa->aaa_intr, IPL_VM, IST_LEVEL, bcmmbox_intr, sc); if (sc->sc_intrh == NULL) { aprint_error_dev(sc->sc_dev, "unable to establish interrupt\n"); return; } /* enable mbox interrupt */ bus_space_write_4(sc->sc_iot, sc->sc_ioh, BCM2835_MBOX_CFG, BCM2835_MBOX_CFG_DATAIRQEN); if (bcm2835mbox_sc == NULL) bcm2835mbox_sc = sc; baa.baa_dmat = aaa->aaa_dmat; sc->sc_platdev = config_found_ia(self, "bcmmboxbus", &baa, NULL); } static int bcmmbox_intr1(struct bcm2835mbox_softc *sc, int cv) { uint32_t mbox, chan, data; int ret = 0; KASSERT(mutex_owned(&sc->sc_intr_lock)); bus_space_barrier(sc->sc_iot, sc->sc_ioh, 0, BCM2835_MBOX_SIZE, BUS_SPACE_BARRIER_READ); while ((bus_space_read_4(sc->sc_iot, sc->sc_ioh, BCM2835_MBOX0_STATUS) & BCM2835_MBOX_STATUS_EMPTY) == 0) { mbox = bus_space_read_4(sc->sc_iot, sc->sc_ioh, BCM2835_MBOX0_READ); chan = BCM2835_MBOX_CHAN(mbox); data = BCM2835_MBOX_DATA(mbox); ret = 1; if (BCM2835_MBOX_CHAN(sc->sc_mbox[chan]) != 0) { aprint_error("bcmmbox_intr: chan %d overflow\n",chan); continue; } sc->sc_mbox[chan] = data | BCM2835_MBOX_CHANMASK; if (cv) cv_broadcast(&sc->sc_chan[chan]); } return ret; } static int bcmmbox_intr(void *cookie) { struct bcm2835mbox_softc *sc = cookie; int ret; mutex_enter(&sc->sc_intr_lock); ret = bcmmbox_intr1(sc, 1); mutex_exit(&sc->sc_intr_lock); return ret; } void bcmmbox_read(uint8_t chan, uint32_t *data) { struct bcm2835mbox_softc *sc = bcm2835mbox_sc; KASSERT(sc != NULL); mutex_enter(&sc->sc_lock); mutex_enter(&sc->sc_intr_lock); while (BCM2835_MBOX_CHAN(sc->sc_mbox[chan]) == 0) { if (cold) bcmmbox_intr1(sc, 0); else cv_wait(&sc->sc_chan[chan], &sc->sc_intr_lock); } *data = BCM2835_MBOX_DATA(sc->sc_mbox[chan]); sc->sc_mbox[chan] = 0; mutex_exit(&sc->sc_intr_lock); mutex_exit(&sc->sc_lock); } void bcmmbox_write(uint8_t chan, uint32_t data) { struct bcm2835mbox_softc *sc = bcm2835mbox_sc; KASSERT(sc != NULL); KASSERT(BCM2835_MBOX_CHAN(chan) == chan); KASSERT(BCM2835_MBOX_CHAN(data) == 0); mutex_enter(&sc->sc_lock); bcm2835_mbox_write(sc->sc_iot, sc->sc_ioh, chan, data); mutex_exit(&sc->sc_lock); } int bcmmbox_request(uint8_t chan, void *buf, size_t buflen, uint32_t *pres) { struct bcm2835mbox_softc *sc = bcm2835mbox_sc; void *dma_buf; bus_dmamap_t map; bus_dma_segment_t segs[1]; int nsegs; int error; KASSERT(sc != NULL); error = bus_dmamem_alloc(sc->sc_dmat, buflen, 16, 0, segs, 1, &nsegs, BUS_DMA_WAITOK); if (error) return error; error = bus_dmamem_map(sc->sc_dmat, segs, nsegs, buflen, &dma_buf, BUS_DMA_WAITOK); if (error) goto map_failed; error = bus_dmamap_create(sc->sc_dmat, buflen, 1, buflen, 0, BUS_DMA_WAITOK, &map); if (error) goto create_failed; error = bus_dmamap_load(sc->sc_dmat, map, dma_buf, buflen, NULL, BUS_DMA_WAITOK); if (error) goto load_failed; memcpy(dma_buf, buf, buflen); bus_dmamap_sync(sc->sc_dmat, map, 0, buflen, BUS_DMASYNC_PREWRITE|BUS_DMASYNC_PREREAD); bcmmbox_write(chan, map->dm_segs[0].ds_addr); bcmmbox_read(chan, pres); bus_dmamap_sync(sc->sc_dmat, map, 0, buflen, BUS_DMASYNC_POSTWRITE|BUS_DMASYNC_POSTREAD); memcpy(buf, dma_buf, buflen); bus_dmamap_unload(sc->sc_dmat, map); load_failed: bus_dmamap_destroy(sc->sc_dmat, map); create_failed: bus_dmamem_unmap(sc->sc_dmat, dma_buf, buflen); map_failed: bus_dmamem_free(sc->sc_dmat, segs, nsegs); return error; }