qemu/include/hw/nvram/chrp_nvram.h
Markus Armbruster ec150c7e09 include: Make headers more self-contained
Back in 2016, we discussed[1] rules for headers, and these were
generally liked:

1. Have a carefully curated header that's included everywhere first.  We
   got that already thanks to Peter: osdep.h.

2. Headers should normally include everything they need beyond osdep.h.
   If exceptions are needed for some reason, they must be documented in
   the header.  If all that's needed from a header is typedefs, put
   those into qemu/typedefs.h instead of including the header.

3. Cyclic inclusion is forbidden.

This patch gets include/ closer to obeying 2.

It's actually extracted from my "[RFC] Baby steps towards saner
headers" series[2], which demonstrates a possible path towards
checking 2 automatically.  It passes the RFC test there.

[1] Message-ID: <87h9g8j57d.fsf@blackfin.pond.sub.org>
    https://lists.nongnu.org/archive/html/qemu-devel/2016-03/msg03345.html
[2] Message-Id: <20190711122827.18970-1-armbru@redhat.com>
    https://lists.nongnu.org/archive/html/qemu-devel/2019-07/msg02715.html

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-Id: <20190812052359.30071-2-armbru@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
2019-08-16 13:31:51 +02:00

57 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