1 /* $NetBSD: octeon_rnm.c,v 1.2 2019/01/08 19:41:09 jdolecek Exp $ */ 2 3 /* 4 * Copyright (c) 2007 Internet Initiative Japan, Inc. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <sys/cdefs.h> 30 __KERNEL_RCSID(0, "$NetBSD: octeon_rnm.c,v 1.2 2019/01/08 19:41:09 jdolecek Exp $"); 31 32 #include <sys/param.h> 33 #include <sys/device.h> 34 #include <sys/systm.h> 35 #include <sys/sysctl.h> 36 #include <sys/kernel.h> 37 #include <sys/rndsource.h> 38 39 #include <mips/locore.h> 40 #include <mips/cavium/include/iobusvar.h> 41 #include <mips/cavium/dev/octeon_rnmreg.h> 42 #include <mips/cavium/dev/octeon_corereg.h> 43 #include <mips/cavium/octeonvar.h> 44 45 #include <sys/bus.h> 46 47 #define RNG_DELAY_CLOCK 91 48 #define RNG_DEF_BURST_COUNT 10 49 50 int octeon_rnm_burst_count = RNG_DEF_BURST_COUNT; 51 52 struct octeon_rnm_softc { 53 device_t sc_dev; 54 55 bus_space_tag_t sc_bust; 56 bus_space_handle_t sc_regh; 57 58 krndsource_t sc_rndsrc; /* /dev/random source */ 59 struct callout sc_rngto; /* rng timeout */ 60 int sc_rnghz; /* rng poll time */ 61 }; 62 63 static int octeon_rnm_match(device_t, struct cfdata *, void *); 64 static void octeon_rnm_attach(device_t, device_t, void *); 65 static void octeon_rnm_rng(void *); 66 static inline uint64_t octeon_rnm_load(struct octeon_rnm_softc *); 67 static inline int octeon_rnm_iobdma(struct octeon_rnm_softc *); 68 69 CFATTACH_DECL_NEW(octeon_rnm, sizeof(struct octeon_rnm_softc), 70 octeon_rnm_match, octeon_rnm_attach, NULL, NULL); 71 72 static int 73 octeon_rnm_match(device_t parent, struct cfdata *cf, void *aux) 74 { 75 struct iobus_attach_args *aa = aux; 76 int result = 0; 77 78 if (strcmp(cf->cf_name, aa->aa_name) != 0) 79 goto out; 80 if (cf->cf_unit != aa->aa_unitno) 81 goto out; 82 result = 1; 83 84 out: 85 return result; 86 } 87 88 static void 89 octeon_rnm_attach(device_t parent, device_t self, void *aux) 90 { 91 struct octeon_rnm_softc *sc = device_private(self); 92 struct iobus_attach_args *aa = aux; 93 int status; 94 95 aprint_normal("\n"); 96 97 sc->sc_dev = self; 98 sc->sc_bust = aa->aa_bust; 99 status = bus_space_map(aa->aa_bust, aa->aa_unit->addr, RNM_SIZE, 100 0, &sc->sc_regh); 101 if (status != 0) 102 panic(": can't map i/o space"); 103 104 bus_space_write_8(sc->sc_bust, sc->sc_regh, RNM_CTL_STATUS_OFFSET, 105 RNM_CTL_STATUS_RNG_EN | RNM_CTL_STATUS_ENT_EN); 106 107 if (hz >= 100) 108 sc->sc_rnghz = hz / 100; 109 else 110 sc->sc_rnghz = 1; 111 112 rnd_attach_source(&sc->sc_rndsrc, device_xname(sc->sc_dev), 113 RND_TYPE_RNG, RND_FLAG_NO_ESTIMATE); 114 115 callout_init(&sc->sc_rngto, 0); 116 117 octeon_rnm_rng(sc); 118 119 aprint_normal("%s: random number generator enabled: %dhz\n", 120 device_xname(sc->sc_dev), sc->sc_rnghz); 121 } 122 123 static void 124 octeon_rnm_rng(void *vsc) 125 { 126 struct octeon_rnm_softc *sc = vsc; 127 uint64_t rn; 128 int i; 129 130 for (i = 0; i < octeon_rnm_burst_count; i++) { 131 rn = octeon_rnm_load(sc); 132 rnd_add_data(&sc->sc_rndsrc, 133 &rn, sizeof(rn), sizeof(rn) * NBBY); 134 /* 135 * XXX 136 * delay should be over RNG_DELAY_CLOCK cycles at least, 137 * we need nanodelay() or clkdelay(). 138 */ 139 delay(1); 140 } 141 142 callout_reset(&sc->sc_rngto, sc->sc_rnghz, octeon_rnm_rng, sc); 143 } 144 145 static inline uint64_t 146 octeon_rnm_load(struct octeon_rnm_softc *sc) 147 { 148 uint64_t addr = 149 RNM_OPERATION_BASE_IO_BIT | 150 __BITS64_SET(RNM_OPERATION_BASE_MAJOR_DID, 0x08) | 151 __BITS64_SET(RNM_OPERATION_BASE_SUB_DID, 0x00); 152 153 return octeon_xkphys_read_8(addr); 154 } 155 156 static inline int 157 octeon_rnm_iobdma(struct octeon_rnm_softc *sc) 158 { 159 160 /* XXX */ 161 return 0; 162 } 163 164 SYSCTL_SETUP(octeon_rnm_sysctl, "sysctl octeon_rnm subtree setup") 165 { 166 int rc, root_num; 167 const struct sysctlnode *node; 168 169 if ( (rc = sysctl_createv(clog, 0, NULL, NULL, 170 CTLFLAG_PERMANENT, CTLTYPE_NODE, "hw", NULL, 171 NULL, 0, NULL, 0, CTL_HW, CTL_EOL)) != 0) { 172 goto err; 173 } 174 175 if ( (rc = sysctl_createv(clog, 0, NULL, &node, 176 CTLFLAG_PERMANENT, CTLTYPE_NODE, "octeon_rnm", 177 SYSCTL_DESCR("octeon_rnm controls"), 178 NULL, 0, NULL, 0, CTL_HW, CTL_CREATE, CTL_EOL)) != 0) { 179 goto err; 180 } 181 182 root_num = node->sysctl_num; 183 184 if ( (rc = sysctl_createv(clog, 0, NULL, NULL, 185 CTLFLAG_PERMANENT|CTLFLAG_READWRITE, 186 CTLTYPE_INT, "burst_count", 187 SYSCTL_DESCR("Burst read count per callout"), 188 NULL, 0, &octeon_rnm_burst_count, 189 0, CTL_HW, root_num, CTL_CREATE, CTL_EOL)) != 0) { 190 goto err; 191 } 192 193 return; 194 err: 195 printf("%s: sysctl_createv failed (rc = %d)\n", __func__, rc); 196 } 197