1 /* 2 * Copyright (C) 2006 Michael Brown <mbrown (at) fensystems.co.uk>. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License as 6 * published by the Free Software Foundation; either version 2 of the 7 * License, or any later version. 8 * 9 * This program is distributed in the hope that it will be useful, but 10 * WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 * General Public License for more details. 13 * 14 * You should have received a copy of the GNU General Public License 15 * along with this program; if not, write to the Free Software 16 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. 17 */ 18 19 FILE_LICENCE ( GPL2_OR_LATER ); 20 21 #include <stdint.h> 22 #include <string.h> 23 #include <errno.h> 24 #include <assert.h> 25 #include <gpxe/nvs.h> 26 27 /** @file 28 * 29 * Non-volatile storage 30 * 31 */ 32 33 /** 34 * Read from non-volatile storage device 35 * 36 * @v nvs NVS device 37 * @v address Address from which to read 38 * @v data Data buffer 39 * @v len Length of data buffer 40 * @ret rc Return status code 41 */ 42 int nvs_read ( struct nvs_device *nvs, unsigned int address, 43 void *data, size_t len ) { 44 size_t frag_len; 45 int rc; 46 47 /* We don't even attempt to handle buffer lengths that aren't 48 * an integral number of words. 49 */ 50 assert ( ( len & ( ( 1 << nvs->word_len_log2 ) - 1 ) ) == 0 ); 51 52 while ( len ) { 53 54 /* Calculate space remaining up to next block boundary */ 55 frag_len = ( ( nvs->block_size - 56 ( address & ( nvs->block_size - 1 ) ) ) 57 << nvs->word_len_log2 ); 58 59 /* Limit to space remaining in buffer */ 60 if ( frag_len > len ) 61 frag_len = len; 62 63 /* Read this portion of the buffer from the device */ 64 if ( ( rc = nvs->read ( nvs, address, data, frag_len ) ) != 0 ) 65 return rc; 66 67 /* Update parameters */ 68 data += frag_len; 69 address += ( frag_len >> nvs->word_len_log2 ); 70 len -= frag_len; 71 } 72 73 return 0; 74 } 75 76 /** 77 * Verify content of non-volatile storage device 78 * 79 * @v nvs NVS device 80 * @v address Address from which to read 81 * @v data Data to compare against 82 * @v len Length of data buffer 83 * @ret rc Return status code 84 */ 85 static int nvs_verify ( struct nvs_device *nvs, unsigned int address, 86 const void *data, size_t len ) { 87 uint8_t read_data[len]; 88 int rc; 89 90 /* Read data into temporary buffer */ 91 if ( ( rc = nvs_read ( nvs, address, read_data, len ) ) != 0 ) 92 return rc; 93 94 /* Compare data */ 95 if ( memcmp ( data, read_data, len ) != 0 ) { 96 DBG ( "NVS %p verification failed at %#04x+%zd\n", 97 nvs, address, len ); 98 return -EIO; 99 } 100 101 return 0; 102 } 103 104 /** 105 * Write to non-volatile storage device 106 * 107 * @v nvs NVS device 108 * @v address Address to which to write 109 * @v data Data buffer 110 * @v len Length of data buffer 111 * @ret rc Return status code 112 */ 113 int nvs_write ( struct nvs_device *nvs, unsigned int address, 114 const void *data, size_t len ) { 115 size_t frag_len; 116 int rc; 117 118 /* We don't even attempt to handle buffer lengths that aren't 119 * an integral number of words. 120 */ 121 assert ( ( len & ( ( 1 << nvs->word_len_log2 ) - 1 ) ) == 0 ); 122 123 while ( len ) { 124 125 /* Calculate space remaining up to next block boundary */ 126 frag_len = ( ( nvs->block_size - 127 ( address & ( nvs->block_size - 1 ) ) ) 128 << nvs->word_len_log2 ); 129 130 /* Limit to space remaining in buffer */ 131 if ( frag_len > len ) 132 frag_len = len; 133 134 /* Write this portion of the buffer to the device */ 135 if ( ( rc = nvs->write ( nvs, address, data, frag_len ) ) != 0) 136 return rc; 137 138 /* Read back and verify data */ 139 if ( ( rc = nvs_verify ( nvs, address, data, frag_len ) ) != 0) 140 return rc; 141 142 /* Update parameters */ 143 data += frag_len; 144 address += ( frag_len >> nvs->word_len_log2 ); 145 len -= frag_len; 146 } 147 148 return 0; 149 } 150
