minix/commands/eepromread/board_info.c
Thomas Cort 437177b028 i2c: increase BUFLEN/CMDLEN to 128, add page flag.
128 byte reads are much more common than 32 byte reads. The message
passing + setup/teardown for a read is much more expensive, in terms
of time, than the reading itself. A slightly bigger struct is well
worth the time savings. This reduces read times for /dev/eeprom
from 57 seconds per 4KB to 14 seconds.

Additionally, make sending the page address in the eeprom driver
and utility optional. This can save a little time when reading
within the same page and allows support for smaller devices that
don't support pages (example: chips containing EDID).

Change-Id: Ie48087caee40c11fa241d1555fce9309ddd27b43
2013-07-27 08:21:37 -04:00

87 lines
2.1 KiB
C

#include <minix/i2c.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "eepromread.h"
/*
* Attempt to read the board info from an eeprom on this board.
* Currently only supports the BeagleBone and BeagleBone Black.
* In the future, this could be expanded to support cape EEPROMs.
*/
static int board_info_beaglebone(int fd, i2c_addr_t address, int flags);
/* Memory Layout of the BeagleBone and BeagleBone Black EEPROM */
typedef struct beaglebone_info
{
uint8_t magic_number[4]; /* Should be 0xaa 0x55 0x33 0xee */
char board_name[8]; /* Warning: strings not NULL terminated */
char version[4];
char serial_number[12];
char config[32]; /* All 0x00 on BeagleBone White */
char mac_addrs[3][6]; /* Not set on BeagleBone White */
} beaglebone_info_t;
static int
board_info_beaglebone(int fd, i2c_addr_t address, int flags)
{
int r;
int i, j;
char s[33];
beaglebone_info_t boneinfo;
r = eeprom_read(fd, address, 0x0000, &boneinfo,
sizeof(beaglebone_info_t), flags);
if (r == -1) {
fprintf(stderr, "Failed to read BeagleBone info r=%d\n", r);
return -1;
}
fprintf(stdout, "%-16s: 0x%x%x%x%x\n", "MAGIC_NUMBER",
boneinfo.magic_number[0], boneinfo.magic_number[1],
boneinfo.magic_number[2], boneinfo.magic_number[3]);
memset(s, '\0', 33);
memcpy(s, boneinfo.board_name, 8);
fprintf(stdout, "%-16s: %s\n", "BOARD_NAME", s);
memset(s, '\0', 33);
memcpy(s, boneinfo.version, 4);
fprintf(stdout, "%-16s: %s\n", "VERSION", s);
memcpy(s, boneinfo.serial_number, 12);
fprintf(stdout, "%-16s: %s\n", "SERIAL_NUMBER", s);
return 0;
}
int
board_info(int fd, i2c_addr_t address, int flags)
{
int r;
uint8_t magic_number[4];
r = eeprom_read(fd, address, 0x0000, &magic_number, 4, flags);
if (r == -1) {
printf("%-16s: %s\n", "BOARD_NAME", "UNKNOWN");
return 0;
}
if (magic_number[0] == 0xaa && magic_number[1] == 0x55 &&
magic_number[2] == 0x33 && magic_number[3] == 0xee) {
board_info_beaglebone(fd, address, flags);
} else {
printf("%-16s: %s\n", "BOARD_NAME", "UNKNOWN");
}
return 0;
}