/* $OpenBSD: bcm2835_mbox.c,v 1.5 2024/05/28 09:19:04 claudio Exp $ */ /* * Copyright (c) 2020 Tobias Heider * Copyright (c) 2019 Neil Ashford * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ /*- * 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 #include #include #include #include #include #include #include #include #include #define DEVNAME(sc) ((sc)->sc_dev.dv_xname) struct cfdriver bcmmbox_cd = { NULL, "bcmmbox", DV_DULL }; struct bcmmbox_softc { struct device sc_dev; bus_space_tag_t sc_iot; bus_space_handle_t sc_ioh; bus_dma_tag_t sc_dmat; bus_dmamap_t sc_dmamap; void *sc_ih; struct mutex sc_intr_lock; int sc_chan[BCMMBOX_NUM_CHANNELS]; uint32_t sc_mbox[BCMMBOX_NUM_CHANNELS]; }; static struct bcmmbox_softc *bcmmbox_sc; int bcmmbox_match(struct device *, void *, void *); void bcmmbox_attach(struct device *, struct device *, void *); const struct cfattach bcmmbox_ca = { sizeof(struct bcmmbox_softc), bcmmbox_match, bcmmbox_attach, }; uint32_t bcmmbox_reg_read(struct bcmmbox_softc *, int); void bcmmbox_reg_write(struct bcmmbox_softc *, int, uint32_t); void bcmmbox_reg_flush(struct bcmmbox_softc *, int); int bcmmbox_intr(void *); int bcmmbox_intr_helper(struct bcmmbox_softc *, int); int bcmmbox_match(struct device *parent, void *match, void *aux) { struct fdt_attach_args *faa = aux; return OF_is_compatible(faa->fa_node, "brcm,bcm2835-mbox"); } void bcmmbox_attach(struct device *parent, struct device *self, void *aux) { struct bcmmbox_softc *sc = (struct bcmmbox_softc *)self; struct fdt_attach_args *faa = aux; bus_addr_t addr; bus_size_t size; if (bcmmbox_sc) { printf(": a similar device as already attached\n"); return; } bcmmbox_sc = sc; mtx_init(&sc->sc_intr_lock, IPL_VM); if (faa->fa_nreg < 1) { printf(": no registers\n"); return; } addr = faa->fa_reg[0].addr; size = faa->fa_reg[0].size; sc->sc_dmat = faa->fa_dmat; sc->sc_iot = faa->fa_iot; if (bus_space_map(sc->sc_iot, addr, size, 0, &sc->sc_ioh)) { printf(": can't map registers\n"); return; } if (bus_dmamap_create(sc->sc_dmat, ~0UL, 1, ~0UL, 0, BUS_DMA_NOWAIT|BUS_DMA_ALLOCNOW, &sc->sc_dmamap) != 0) { printf(": unable to create dma map\n"); goto clean_bus_space_map; } sc->sc_ih = fdt_intr_establish(faa->fa_node, IPL_VM, bcmmbox_intr, sc, DEVNAME(sc)); if (sc->sc_ih == NULL) { printf(": failed to establish interrupt\n"); goto clean_dmamap; } /* enable interrupt in hardware */ bcmmbox_reg_write(sc, BCMMBOX_CFG, BCMMBOX_CFG_DATA_IRQ_EN); printf("\n"); return; clean_dmamap: bus_dmamap_destroy(sc->sc_dmat, sc->sc_dmamap); clean_bus_space_map: bus_space_unmap(sc->sc_iot, sc->sc_ioh, size); } uint32_t bcmmbox_reg_read(struct bcmmbox_softc *sc, int addr) { return bus_space_read_4(sc->sc_iot, sc->sc_ioh, addr); } void bcmmbox_reg_write(struct bcmmbox_softc *sc, int addr, uint32_t val) { bus_space_write_4(sc->sc_iot, sc->sc_ioh, addr, val); } void bcmmbox_reg_flush(struct bcmmbox_softc *sc, int flags) { bus_space_barrier(sc->sc_iot, sc->sc_ioh, 0, BCMMBOX_SIZE, flags); } int bcmmbox_intr(void *cookie) { struct bcmmbox_softc *sc = cookie; int ret; mtx_enter(&sc->sc_intr_lock); ret = bcmmbox_intr_helper(sc, 1); mtx_leave(&sc->sc_intr_lock); return ret; } int bcmmbox_intr_helper(struct bcmmbox_softc *sc, int broadcast) { uint32_t mbox, chan, data; int ret = 0; bcmmbox_reg_flush(sc, BUS_SPACE_BARRIER_READ); while (!ISSET(bcmmbox_reg_read(sc, BCMMBOX_STATUS), BCMMBOX_STATUS_EMPTY)) { mbox = bcmmbox_reg_read(sc, BCMMBOX0_READ); chan = mbox & BCMMBOX_CHANNEL_MASK; data = mbox & ~BCMMBOX_CHANNEL_MASK; ret = 1; if ((sc->sc_mbox[chan] & BCMMBOX_CHANNEL_MASK) != 0) { printf("%s: chan %d overflow\n", DEVNAME(sc), chan); continue; } sc->sc_mbox[chan] = data | BCMMBOX_CHANNEL_MASK; if (broadcast) wakeup(&sc->sc_chan[chan]); } return ret; } void bcmmbox_read(uint8_t chan, uint32_t *data) { struct bcmmbox_softc *sc = bcmmbox_sc; uint32_t mbox, rchan, rdata, status; KASSERT(sc != NULL); KASSERT(chan == (chan & BCMMBOX_CHANNEL_MASK)); while (1) { bcmmbox_reg_flush(sc, BUS_SPACE_BARRIER_READ); status = bcmmbox_reg_read(sc, BCMMBOX0_STATUS); if (ISSET(status, BCMMBOX_STATUS_EMPTY)) continue; mbox = bcmmbox_reg_read(sc, BCMMBOX0_READ); rchan = mbox & BCMMBOX_CHANNEL_MASK; rdata = mbox & ~BCMMBOX_CHANNEL_MASK; if (rchan == chan) { *data = rdata; return; } } } void bcmmbox_write(uint8_t chan, uint32_t data) { struct bcmmbox_softc *sc = bcmmbox_sc; uint32_t rdata; KASSERT(sc != NULL); KASSERT(chan == (chan & BCMMBOX_CHANNEL_MASK)); KASSERT(data == (data & ~BCMMBOX_CHANNEL_MASK)); while (1) { bcmmbox_reg_flush(sc, BUS_SPACE_BARRIER_READ); rdata = bcmmbox_reg_read(sc, BCMMBOX0_STATUS); if (!ISSET(rdata, BCMMBOX_STATUS_FULL)) break; } bcmmbox_reg_write(sc, BCMMBOX1_WRITE, chan | data); bcmmbox_reg_flush(sc, BUS_SPACE_BARRIER_WRITE); } int bcmmbox_post(uint8_t chan, void *buf, size_t len, uint32_t *res) { struct bcmmbox_softc *sc = bcmmbox_sc; bus_dmamap_t map; int error; KASSERT(sc != NULL); if (sc == NULL) return (ENXIO); map = sc->sc_dmamap; error = bus_dmamap_load(sc->sc_dmat, map, buf, len, NULL, BUS_DMA_NOWAIT | BUS_DMA_READ | BUS_DMA_WRITE); if (error != 0) return (error); bus_dmamap_sync(sc->sc_dmat, map, 0, len, BUS_DMASYNC_PREREAD | BUS_DMASYNC_PREWRITE); bcmmbox_write(chan, map->dm_segs[0].ds_addr); bcmmbox_read(chan, res); bus_dmamap_sync(sc->sc_dmat, map, 0, len, BUS_DMASYNC_POSTREAD | BUS_DMASYNC_POSTWRITE); bus_dmamap_unload(sc->sc_dmat, map); return (0); }