1 /* $OpenBSD: octrng.c,v 1.9 2020/05/29 04:42:24 deraadt Exp $ */ 2 /* 3 * Copyright (c) 2013 Paul Irofti <paul@irofti.net> 4 * 5 * Permission to use, copy, modify, and/or 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 #include <sys/timeout.h> 22 23 #include <machine/octeonvar.h> 24 #include <machine/octeonreg.h> 25 #include <octeon/dev/iobusvar.h> 26 27 int octrng_match(struct device *, void *, void *); 28 void octrng_attach(struct device *, struct device *, void *); 29 void octrng_rnd(void *arg); 30 31 #ifdef OCTRNG_DEBUG 32 #define DPRINTF(x) printf x 33 #else 34 #define DPRINTF(x) 35 #endif 36 37 #define OCTRNG_MAP_SIZE 8ULL 38 39 /* OCTRNG_ENTROPY_ADDR 0x8001400000000000ULL */ 40 #define OCTRNG_MAJORDID 8ULL 41 #define OCTRNG_ENTROPY_ADDR (((uint64_t)1 << 48) | \ 42 ((uint64_t)(OCTRNG_MAJORDID & 0x1f) << 43)) 43 #define OCTRNG_ENTROPY_REG 0 44 45 #define OCTRNG_CONTROL_ADDR 0x0001180040000000ULL 46 47 #define OCTRNG_RESET (1ULL << 3) 48 #define OCTRNG_ENABLE_OUTPUT (1ULL << 1) 49 #define OCTRNG_ENABLE_ENTROPY (1ULL << 0) 50 51 struct octrng_softc { 52 struct device sc_dev; 53 struct timeout sc_to; 54 struct iobus_attach_args *sc_io; 55 56 bus_space_tag_t sc_iot; 57 bus_space_handle_t sc_ioh; 58 }; 59 60 struct cfattach octrng_ca = { 61 sizeof(struct octrng_softc), octrng_match, octrng_attach 62 }; 63 64 struct cfdriver octrng_cd = { 65 NULL, "octrng", DV_DULL 66 }; 67 68 69 int 70 octrng_match(struct device *parent, void *match, void *aux) 71 { 72 struct iobus_attach_args *aa = aux; 73 struct cfdata *cf = match; 74 75 /* XXX: check for board type */ 76 77 if (strcmp(aa->aa_name, cf->cf_driver->cd_name) != 0) 78 return (0); 79 80 return (1); 81 } 82 83 void 84 octrng_attach(struct device *parent, struct device *self, void *aux) 85 { 86 struct octrng_softc *sc = (void *)self; 87 sc->sc_io = aux; 88 89 uint64_t control_reg; 90 91 sc->sc_iot = sc->sc_io->aa_bust; 92 93 if (bus_space_map(sc->sc_iot, OCTEON_RNG_BASE, OCTRNG_MAP_SIZE, 0, 94 &sc->sc_ioh)) { 95 printf(": can't map registers"); 96 } 97 98 control_reg = octeon_xkphys_read_8(OCTRNG_CONTROL_ADDR); 99 control_reg |= (OCTRNG_ENABLE_OUTPUT | OCTRNG_ENABLE_ENTROPY); 100 octeon_xkphys_write_8(OCTRNG_CONTROL_ADDR, control_reg); 101 102 timeout_set(&sc->sc_to, octrng_rnd, sc); 103 104 timeout_add_sec(&sc->sc_to, 5); 105 106 printf("\n"); 107 } 108 109 void 110 octrng_rnd(void *arg) 111 { 112 struct octrng_softc *sc = arg; 113 uint64_t value; 114 115 value = bus_space_read_8(sc->sc_iot, sc->sc_ioh, OCTRNG_ENTROPY_REG); 116 117 DPRINTF(("%#llX ", value)); /* WARNING: very verbose */ 118 119 enqueue_randomness(value); 120 timeout_add_msec(&sc->sc_to, 10); 121 } 122