1 /* 2 * Common Hardware Reference Platform NVRAM functions. 3 * 4 * This code is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License as published 6 * by the Free Software Foundation; either version 2 of the License, 7 * or (at your option) any later version. 8 * 9 * This program is distributed in the hope that it will be useful, 10 * but WITHOUT ANY WARRANTY; without even the implied warranty of 11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 * GNU 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, see <http://www.gnu.org/licenses/>. 16 */ 17 18 #ifndef CHRP_NVRAM_H 19 #define CHRP_NVRAM_H 20 21 #include "qemu/bswap.h" 22 23 /* OpenBIOS NVRAM partition */ 24 typedef struct { 25 uint8_t signature; 26 uint8_t checksum; 27 uint16_t len; /* Big endian, length divided by 16 */ 28 char name[12]; 29 } ChrpNvramPartHdr; 30 31 #define CHRP_NVPART_SYSTEM 0x70 32 #define CHRP_NVPART_FREE 0x7f 33 34 static inline void 35 chrp_nvram_finish_partition(ChrpNvramPartHdr *header, uint32_t size) 36 { 37 unsigned int i, sum; 38 uint8_t *tmpptr; 39 40 /* Length divided by 16 */ 41 header->len = cpu_to_be16(size >> 4); 42 43 /* Checksum */ 44 tmpptr = (uint8_t *)header; 45 sum = *tmpptr; 46 for (i = 0; i < 14; i++) { 47 sum += tmpptr[2 + i]; 48 sum = (sum + ((sum & 0xff00) >> 8)) & 0xff; 49 } 50 header->checksum = sum & 0xff; 51 } 52 53 /* chrp_nvram_create_system_partition() failure is fatal */ 54 int chrp_nvram_create_system_partition(uint8_t *data, int min_len, int max_len); 55 int chrp_nvram_create_free_partition(uint8_t *data, int len); 56 57 #endif 58