diff options
Diffstat (limited to 'util/flashrom/lbtable.c')
| -rw-r--r-- | util/flashrom/lbtable.c | 193 |
1 files changed, 193 insertions, 0 deletions
diff --git a/util/flashrom/lbtable.c b/util/flashrom/lbtable.c new file mode 100644 index 0000000000..f98267273e --- /dev/null +++ b/util/flashrom/lbtable.c @@ -0,0 +1,193 @@ +#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; +} |