nvram.c revision 1.1
1 /* $NetBSD: nvram.c,v 1.1 1996/01/06 20:11:08 leo 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 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by Leo Weppelman. 18 * 4. The name of the author may not be used to endorse or promote products 19 * derived from this software without specific prior written permission 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 /* 34 * Nvram driver 35 */ 36 37 #include <sys/param.h> 38 #include <sys/conf.h> 39 #include <sys/kernel.h> 40 #include <sys/proc.h> 41 #include <sys/systm.h> 42 #include <sys/device.h> 43 #include <sys/buf.h> 44 #include <sys/uio.h> 45 46 #include <machine/iomap.h> 47 48 #include <atari/dev/clockreg.h> 49 #include <atari/dev/nvramvar.h> 50 51 #include "nvr.h" 52 53 #define MC_NVRAM_CSUM (MC_NVRAM_START + MC_NVRAM_SIZE - 2) 54 55 #if NNVR > 0 56 static void nvram_set_csum __P((u_char csum)); 57 static int nvram_csum_valid __P((u_char csum)); 58 static u_char nvram_csum __P((void)); 59 60 /* 61 * Auto config stuff.... 62 */ 63 static void nvr_attach __P((struct device *, struct device *, void *)); 64 static int nvr_match __P((struct device *, struct cfdata *, void *)); 65 66 struct cfdriver nvrcd = { 67 NULL, "nvr", (cfmatch_t)nvr_match, nvr_attach, 68 DV_DULL, sizeof(struct nvr_softc), NULL, 0 }; 69 70 /*ARGSUSED*/ 71 static int 72 nvr_match(pdp, cfp, auxp) 73 struct device *pdp; 74 struct cfdata *cfp; 75 void *auxp; 76 { 77 if (!strcmp((char *)auxp, "nvr")) 78 return (1); 79 return (0); 80 } 81 82 /*ARGSUSED*/ 83 static void 84 nvr_attach(pdp, dp, auxp) 85 struct device *pdp, *dp; 86 void *auxp; 87 { 88 struct nvr_softc *nvr_soft; 89 int nreg; 90 91 /* 92 * Check the validity of the NVram contents 93 */ 94 if (!nvram_csum_valid(nvram_csum())) { 95 printf(": Invalid checksum - re-initialized"); 96 for (nreg = MC_NVRAM_START; nreg < MC_NVRAM_CSUM; nreg++) 97 mc146818_write(RTC, nreg, 0); 98 nvram_set_csum(nvram_csum()); 99 } 100 nvr_soft = nvrcd.cd_devs[0]; 101 nvr_soft->nvr_flags = NVR_CONFIGURED; 102 printf("\n"); 103 } 104 /* 105 * End of auto config stuff.... 106 */ 107 #endif /* NNVR > 0 */ 108 109 /* 110 * Kernel internal interface 111 */ 112 int 113 nvr_get_byte(byteno) 114 int byteno; 115 { 116 #if NNVR > 0 117 struct nvr_softc *nvr_soft; 118 119 nvr_soft = nvrcd.cd_devs[0]; 120 if (!(nvr_soft->nvr_flags & NVR_CONFIGURED)) 121 return(NVR_INVALID); 122 return (mc146818_read(RTC, byteno + MC_NVRAM_START) & 0xff); 123 #else 124 return(NVR_INVALID); 125 #endif /* NNVR > 0 */ 126 } 127 128 #if NNVR > 0 129 130 nvram_uio(uio) 131 struct uio *uio; 132 { 133 int i; 134 off_t offset; 135 int nleft; 136 u_char buf[MC_NVRAM_CSUM - MC_NVRAM_START + 1]; 137 u_char *p; 138 struct nvr_softc *nvr_soft; 139 140 nvr_soft = nvrcd.cd_devs[0]; 141 if (!(nvr_soft->nvr_flags & NVR_CONFIGURED)) 142 return ENXIO; 143 144 #ifdef NV_DEBUG 145 printf("Request to transfer %d bytes offset: %d, %s nvram\n", 146 (long)uio->uio_resid, (long)uio->uio_offset, 147 (uio->uio_rw == UIO_READ) ? "from" : "to"); 148 #endif /* NV_DEBUG */ 149 150 offset = uio->uio_offset + MC_NVRAM_START; 151 nleft = uio->uio_resid; 152 if (offset + nleft >= MC_NVRAM_CSUM) { 153 if (offset == MC_NVRAM_CSUM) 154 return (0); 155 nleft = MC_NVRAM_CSUM - offset; 156 if (nleft <= 0) 157 return (EINVAL); 158 } 159 #ifdef NV_DEBUG 160 printf("Translated: offset = %d, bytes: %d\n", (long)offset, nleft); 161 #endif /* NV_DEBUG */ 162 163 if (uio->uio_rw == UIO_READ) { 164 for (i = 0, p = buf; i < nleft; i++, p++) 165 *p = mc146818_read(RTC, offset + i); 166 } 167 if (i = uiomove(buf, nleft, uio)) 168 return (i); 169 if (uio->uio_rw == UIO_WRITE) { 170 for (i = 0, p = buf; i < nleft; i++, p++) 171 mc146818_write(RTC, offset + i, *p); 172 nvram_set_csum(nvram_csum()); 173 } 174 return(0); 175 } 176 177 static u_char 178 nvram_csum() 179 { 180 u_char csum; 181 int nreg; 182 183 for (csum = 0, nreg = MC_NVRAM_START; nreg < MC_NVRAM_CSUM; nreg++) 184 csum += mc146818_read(RTC, nreg); 185 return(csum); 186 } 187 188 static int 189 nvram_csum_valid(csum) 190 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(csum) 200 u_char csum; 201 { 202 mc146818_write(RTC, MC_NVRAM_CSUM, ~csum); 203 mc146818_write(RTC, MC_NVRAM_CSUM + 1, csum); 204 } 205 #endif /* NNVR > 0 */ 206
Indexes created Fri Sep 26 08:10:20 GMT 2025