nvram.c revision 1.21
1 /* $NetBSD: nvram.c,v 1.21 2018/01/20 19:33:53 tsutsui Exp $ */ 2 3 /* 4 * Copyright (c) 1995 Leo Weppelman. 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 AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 28 /* 29 * Nvram driver 30 */ 31 32 #include <sys/cdefs.h> 33 __KERNEL_RCSID(0, "$NetBSD: nvram.c,v 1.21 2018/01/20 19:33:53 tsutsui Exp $"); 34 35 #include <sys/param.h> 36 #include <sys/conf.h> 37 #include <sys/kernel.h> 38 #include <sys/proc.h> 39 #include <sys/systm.h> 40 #include <sys/device.h> 41 #include <sys/buf.h> 42 #include <sys/uio.h> 43 44 #include <machine/iomap.h> 45 #include <machine/cpu.h> 46 47 #include <atari/dev/clockreg.h> 48 #include <atari/dev/nvramvar.h> 49 50 #include "ioconf.h" 51 52 #include "nvr.h" 53 54 #ifdef NVRAM_DEBUG 55 #define DPRINTF(a) printf a 56 #else 57 #define DPRINTF(a) 58 #endif 59 60 #define MC_NVRAM_CSUM (MC_NVRAM_START + MC_NVRAM_SIZE - 2) 61 62 #if NNVR > 0 63 static void nvram_set_csum(u_char csum); 64 static int nvram_csum_valid(u_char csum); 65 static u_char nvram_csum(void); 66 67 /* 68 * Auto config stuff.... 69 */ 70 static void nvr_attach(device_t, device_t, void *); 71 static int nvr_match(device_t, cfdata_t, void *); 72 73 CFATTACH_DECL_NEW(nvr, sizeof(struct nvr_softc), 74 nvr_match, nvr_attach, NULL, NULL); 75 76 /*ARGSUSED*/ 77 static int 78 nvr_match(device_t parent, cfdata_t cf, void *aux) 79 { 80 if (!strcmp((char *)aux, "nvr")) 81 return (1); 82 return (0); 83 } 84 85 /*ARGSUSED*/ 86 static void 87 nvr_attach(device_t parent, device_t self, void *aux) 88 { 89 struct nvr_softc *sc; 90 int nreg; 91 92 /* 93 * Check the validity of the NVram contents 94 */ 95 /* XXX: Milan's firmware seems to use different check method */ 96 if ((machineid & ATARI_MILAN) == 0) { 97 if (!nvram_csum_valid(nvram_csum())) { 98 printf(": Invalid checksum - re-initialized"); 99 for (nreg = MC_NVRAM_START; nreg < MC_NVRAM_CSUM; 100 nreg++) 101 mc146818_write(RTC, nreg, 0); 102 nvram_set_csum(nvram_csum()); 103 } 104 } 105 sc = device_private(self); 106 sc->sc_dev = self; 107 sc->sc_flags = NVR_CONFIGURED; 108 printf("\n"); 109 } 110 /* 111 * End of auto config stuff.... 112 */ 113 #endif /* NNVR > 0 */ 114 115 /* 116 * Kernel internal interface 117 */ 118 int 119 nvr_get_byte(int byteno) 120 { 121 #if NNVR > 0 122 struct nvr_softc *sc; 123 124 sc = device_lookup_private(&nvr_cd, 0); 125 if (!(sc->sc_flags & NVR_CONFIGURED)) 126 return(NVR_INVALID); 127 return (mc146818_read(RTC, byteno + MC_NVRAM_START) & 0xff); 128 #else 129 return(NVR_INVALID); 130 #endif /* NNVR > 0 */ 131 } 132 133 #if NNVR > 0 134 135 int 136 nvram_uio(struct uio *uio) 137 { 138 int i; 139 off_t offset; 140 int nleft; 141 u_char buf[MC_NVRAM_CSUM - MC_NVRAM_START + 1]; 142 u_char *p; 143 struct nvr_softc *sc; 144 145 sc = device_lookup_private(&nvr_cd,0); 146 if (!(sc->sc_flags & NVR_CONFIGURED)) 147 return ENXIO; 148 149 DPRINTF(("Request to transfer %d bytes offset: %d, %s nvram\n", 150 (long)uio->uio_resid, (long)uio->uio_offset, 151 (uio->uio_rw == UIO_READ) ? "from" : "to")); 152 153 offset = uio->uio_offset + MC_NVRAM_START; 154 nleft = uio->uio_resid; 155 if (offset + nleft >= MC_NVRAM_CSUM) { 156 if (offset == MC_NVRAM_CSUM) 157 return (0); 158 nleft = MC_NVRAM_CSUM - offset; 159 if (nleft <= 0) 160 return (EINVAL); 161 } 162 DPRINTF(("Translated: offset = %d, bytes: %d\n", (long)offset, nleft)); 163 164 if (uio->uio_rw == UIO_READ) { 165 for (i = 0, p = buf; i < nleft; i++, p++) 166 *p = mc146818_read(RTC, offset + i); 167 } 168 if ((i = uiomove(buf, nleft, uio)) != 0) 169 return (i); 170 if (uio->uio_rw == UIO_WRITE) { 171 for (i = 0, p = buf; i < nleft; i++, p++) 172 mc146818_write(RTC, offset + i, *p); 173 nvram_set_csum(nvram_csum()); 174 } 175 return(0); 176 } 177 178 static u_char 179 nvram_csum(void) 180 { 181 u_char csum; 182 int nreg; 183 184 for (csum = 0, nreg = MC_NVRAM_START; nreg < MC_NVRAM_CSUM; nreg++) 185 csum += mc146818_read(RTC, nreg); 186 return(csum); 187 } 188 189 static int 190 nvram_csum_valid(u_char csum) 191 { 192 if (((~csum & 0xff) != mc146818_read(RTC, MC_NVRAM_CSUM)) 193 || (csum != mc146818_read(RTC, MC_NVRAM_CSUM + 1))) 194 return 0; 195 return 1; 196 } 197 198 static void 199 nvram_set_csum(u_char csum) 200 { 201 mc146818_write(RTC, MC_NVRAM_CSUM, ~csum); 202 mc146818_write(RTC, MC_NVRAM_CSUM + 1, csum); 203 } 204 #endif /* NNVR > 0 */ 205
Indexes created Mon Sep 22 21:09:42 GMT 2025