1 /* $OpenBSD: aplefuse.c,v 1.1 2022/12/17 11:56:44 kettenis Exp $ */ 2 /* 3 * Copyright (c) 2022 Mark Kettenis <kettenis@openbsd.org> 4 * 5 * Permission to use, copy, modify, and distribute this software for any 6 * purpose with or without fee is hereby granted, provided that the above 7 * copyright notice and this permission notice appear in all copies. 8 * 9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES 10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF 11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR 12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES 13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN 14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF 15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. 16 */ 17 18 #include <sys/param.h> 19 #include <sys/systm.h> 20 #include <sys/device.h> 21 22 #include <machine/bus.h> 23 #include <machine/fdt.h> 24 25 #include <dev/ofw/openfirm.h> 26 #include <dev/ofw/ofw_misc.h> 27 #include <dev/ofw/fdt.h> 28 29 struct aplefuse_softc { 30 struct device sc_dev; 31 bus_space_tag_t sc_iot; 32 bus_space_handle_t sc_ioh; 33 bus_size_t sc_ios; 34 35 struct nvmem_device sc_nd; 36 }; 37 38 int aplefuse_match(struct device *, void *, void *); 39 void aplefuse_attach(struct device *, struct device *, void *); 40 41 const struct cfattach aplefuse_ca = { 42 sizeof (struct aplefuse_softc), aplefuse_match, aplefuse_attach 43 }; 44 45 struct cfdriver aplefuse_cd = { 46 NULL, "aplefuse", DV_DULL 47 }; 48 49 int aplefuse_nvmem_read(void *, bus_addr_t, void *, bus_size_t); 50 int aplefuse_nvmem_write(void *, bus_addr_t, const void *, bus_size_t); 51 52 int 53 aplefuse_match(struct device *parent, void *match, void *aux) 54 { 55 struct fdt_attach_args *faa = aux; 56 57 return OF_is_compatible(faa->fa_node, "apple,efuses"); 58 } 59 60 void 61 aplefuse_attach(struct device *parent, struct device *self, void *aux) 62 { 63 struct aplefuse_softc *sc = (struct aplefuse_softc *)self; 64 struct fdt_attach_args *faa = aux; 65 66 if (faa->fa_nreg < 1) { 67 printf(": no registers\n"); 68 return; 69 } 70 71 sc->sc_iot = faa->fa_iot; 72 if (bus_space_map(sc->sc_iot, faa->fa_reg[0].addr, 73 faa->fa_reg[0].size, 0, &sc->sc_ioh)) { 74 printf(": can't map registers\n"); 75 return; 76 } 77 sc->sc_ios = faa->fa_reg[0].size; 78 79 printf("\n"); 80 81 sc->sc_nd.nd_node = faa->fa_node; 82 sc->sc_nd.nd_cookie = sc; 83 sc->sc_nd.nd_read = aplefuse_nvmem_read; 84 nvmem_register(&sc->sc_nd); 85 } 86 87 int 88 aplefuse_nvmem_read(void *cookie, bus_addr_t addr, void *data, bus_size_t size) 89 { 90 struct aplefuse_softc *sc = cookie; 91 uint8_t *p = data; 92 uint32_t value; 93 uint8_t buf[4]; 94 int offset; 95 96 if (addr > sc->sc_ios || size > sc->sc_ios - addr) 97 return EINVAL; 98 99 offset = addr & 0x3; 100 addr &= ~0x3; 101 while (size > 0) { 102 value = bus_space_read_4(sc->sc_iot, sc->sc_ioh, addr); 103 htolem32(buf, value); 104 memcpy(p, &buf[offset], MIN(size, 4 - offset)); 105 size -= MIN(size, 4 - offset); 106 p += MIN(size, 4 - offset); 107 addr += 4; 108 offset = 0; 109 } 110 111 return 0; 112 } 113