historical/m0-applesillicon.git/xnu-qemu-arm64-5.1.0/include/hw/nvram/chrp_nvram.h
2024-01-16 11:20:27 -06:00

56 lines
1.6 KiB
C

/*
* Common Hardware Reference Platform NVRAM functions.
*
* This code is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published
* by the Free Software Foundation; either version 2 of the License,
* or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#ifndef CHRP_NVRAM_H
#define CHRP_NVRAM_H
#include "qemu/bswap.h"
/* OpenBIOS NVRAM partition */
typedef struct {
uint8_t signature;
uint8_t checksum;
uint16_t len; /* Big endian, length divided by 16 */
char name[12];
} ChrpNvramPartHdr;
#define CHRP_NVPART_SYSTEM 0x70
#define CHRP_NVPART_FREE 0x7f
static inline void
chrp_nvram_finish_partition(ChrpNvramPartHdr *header, uint32_t size)
{
unsigned int i, sum;
uint8_t *tmpptr;
/* Length divided by 16 */
header->len = cpu_to_be16(size >> 4);
/* Checksum */
tmpptr = (uint8_t *)header;
sum = *tmpptr;
for (i = 0; i < 14; i++) {
sum += tmpptr[2 + i];
sum = (sum + ((sum & 0xff00) >> 8)) & 0xff;
}
header->checksum = sum & 0xff;
}
int chrp_nvram_create_system_partition(uint8_t *data, int min_len);
int chrp_nvram_create_free_partition(uint8_t *data, int len);
#endif