coreboot-kgpe-d16/util/flashrom/lbtable.c

194 lines
5.1 KiB
C

#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/types.h>
#include <string.h>
#include <errno.h>
#include <sys/mman.h>
#include "../../src/include/boot/linuxbios_tables.h"
#include "debug.h"
char *lb_part=NULL, *lb_vendor=NULL;
static unsigned long compute_checksum(void *addr, unsigned long length)
{
uint8_t *ptr;
volatile union {
uint8_t byte[2];
uint16_t word;
} value;
unsigned long sum;
unsigned long i;
/* In the most straight forward way possible,
* compute an ip style checksum.
*/
sum = 0;
ptr = addr;
for(i = 0; i < length; i++) {
unsigned long value;
value = ptr[i];
if (i & 1) {
value <<= 8;
}
/* Add the new value */
sum += value;
/* Wrap around the carry */
if (sum > 0xFFFF) {
sum = (sum + (sum >> 16)) & 0xFFFF;
}
}
value.byte[0] = sum & 0xff;
value.byte[1] = (sum >> 8) & 0xff;
return (~value.word) & 0xFFFF;
}
#define for_each_lbrec(head, rec) \
for(rec = (struct lb_record *)(((char *)head) + sizeof(*head)); \
(((char *)rec) < (((char *)head) + sizeof(*head) + head->table_bytes)) && \
(rec->size >= 1) && \
((((char *)rec) + rec->size) <= (((char *)head) + sizeof(*head) + head->table_bytes)); \
rec = (struct lb_record *)(((char *)rec) + rec->size))
static int count_lb_records(struct lb_header *head)
{
struct lb_record *rec;
int count;
count = 0;
for_each_lbrec(head, rec) {
count++;
}
return count;
}
static struct lb_header *find_lb_table(void *base, unsigned long start, unsigned long end)
{
unsigned long addr;
/* For now be stupid.... */
for(addr = start; addr < end; addr += 16) {
struct lb_header *head = (struct lb_header *)(((char*)base) + addr);
struct lb_record *recs = (struct lb_record *)(((char*)base) + addr + sizeof(*head));
if (memcmp(head->signature, "LBIO", 4) != 0)
continue;
printf_debug( "Found canidate at: %08lx-%08lx\n",
addr, addr + head->table_bytes);
if (head->header_bytes != sizeof(*head)) {
fprintf(stderr, "Header bytes of %d are incorrect\n",
head->header_bytes);
continue;
}
if (count_lb_records(head) != head->table_entries) {
fprintf(stderr, "bad record count: %d\n",
head->table_entries);
continue;
}
if (compute_checksum((uint8_t *)head, sizeof(*head)) != 0) {
fprintf(stderr, "bad header checksum\n");
continue;
}
if (compute_checksum(recs, head->table_bytes)
!= head->table_checksum) {
fprintf(stderr, "bad table checksum: %04x\n",
head->table_checksum);
continue;
}
fprintf(stdout, "Found LinuxBIOS table at: %08lx\n", addr);
return head;
};
return 0;
}
static void find_mainboard(struct lb_record *ptr, unsigned long addr)
{
struct lb_mainboard *rec;
int max_size;
char vendor[256], part[256];
rec = (struct lb_mainboard *)ptr;
max_size = rec->size - sizeof(*rec);
printf("vendor id: %.*s part id: %.*s\n",
max_size - rec->vendor_idx,
rec->strings + rec->vendor_idx,
max_size - rec->part_number_idx,
rec->strings + rec->part_number_idx);
snprintf(vendor, 255, "%.*s", max_size - rec->vendor_idx,
rec->strings + rec->vendor_idx);
snprintf(part, 255, "%.*s", max_size - rec->part_number_idx,
rec->strings + rec->part_number_idx);
if(lb_part) {
printf("overwritten by command line, vendor id: %s part id: %s\n",
lb_vendor, lb_part);
} else {
lb_part=strdup(part);
lb_vendor=strdup(vendor);
}
}
static struct lb_record *next_record(struct lb_record *rec)
{
return (struct lb_record *)(((char *)rec) + rec->size);
}
static void search_lb_records(struct lb_record *rec, struct lb_record *last,
unsigned long addr)
{
struct lb_record *next;
int count;
count = 0;
for(next = next_record(rec); (rec < last) && (next <= last);
rec = next, addr += rec->size) {
next = next_record(rec);
count++;
if(rec->tag == LB_TAG_MAINBOARD) {
find_mainboard(rec,addr);
break;
}
}
}
int linuxbios_init(void)
{
uint8_t *low_1MB;
struct lb_header *lb_table;
struct lb_record *rec, *last;
int fd;
fd = open("/dev/mem", O_RDONLY);
if (fd < 0) {
fprintf(stderr, "Can not open /dev/mem\n");
exit(-1);
}
low_1MB = mmap(0, 1024*1024, PROT_READ, MAP_SHARED, fd, 0x00000000);
if (low_1MB == ((void *) -1)) {
fprintf(stderr, "Can not mmap /dev/mem at %08lx errno(%d):%s\n",
0x00000000UL, errno, strerror(errno));
exit(-2);
}
lb_table = 0;
if (!lb_table)
lb_table = find_lb_table(low_1MB, 0x00000, 0x1000);
if (!lb_table)
lb_table = find_lb_table(low_1MB, 0xf0000, 1024*1024);
if (lb_table) {
unsigned long addr;
addr = ((char *)lb_table) - ((char *)low_1MB);
printf_debug("lb_table found at address %p\n", lb_table);
rec = (struct lb_record *)(((char *)lb_table) + lb_table->header_bytes);
last = (struct lb_record *)(((char *)rec) + lb_table->table_bytes);
printf_debug("LinuxBIOS header(%d) checksum: %04x table(%d) checksum: %04x entries: %d\n",
lb_table->header_bytes, lb_table->header_checksum,
lb_table->table_bytes, lb_table->table_checksum, lb_table->table_entries);
search_lb_records(rec, last, addr + lb_table->header_bytes);
}
else {
printf("No LinuxBIOS table found.\n");
return -1;
}
return 0;
}