libopenbios/linuxbios_info.c

   1 /* Adapted from Etherboot 5.1.8 */
   2
   3 #include "config.h"
   4 #include "sysinclude.h"
   5 #include "asm/types.h"
   6 #include "asm/io.h"
   7 #include "linuxbios.h"
   8 #include "libopenbios/ipchecksum.h"
   9 #include "libopenbios/sys_info.h"
  10
  11 #ifdef CONFIG_DEBUG_BOOT
  12 #define debug printk
  13 #else
  14 #define debug(x...)
  15 #endif
  16
  17 #define for_each_lbrec(head, rec) \
  18         for(rec = (struct lb_record *)(((char *)head) + sizeof(*head)); \
  19                 (((char *)rec) < (((char *)head) + sizeof(*head) + head->table_bytes))  && \
  20                 (rec->size >= 1) && \
  21                 ((((char *)rec) + rec->size) <= (((char *)head) + sizeof(*head) + head->table_bytes)); \
  22                 rec = (struct lb_record *)(((char *)rec) + rec->size))
  23
  24 static void convert_memmap(struct lb_memory *lbmem, struct sys_info *info)
  25 {
  26     int lbcount;
  27     int i;
  28
  29     lbcount = lbmem->size / sizeof(struct lb_memory_range);
  30     info->memrange = malloc(lbcount * sizeof(struct memrange));
  31     info->n_memranges = 0;
  32     for (i = 0; i < lbcount; i++) {
  33         debug("%#016llx %#016llx %d\n",
  34               (long long)lbmem->map[i].start, (long long)lbmem->map[i].size,
  35               (int) lbmem->map[i].type);
  36         if (lbmem->map[i].type != LB_MEM_RAM)
  37             continue;
  38         info->memrange[info->n_memranges].base = lbmem->map[i].start;
  39         info->memrange[info->n_memranges].size = lbmem->map[i].size;
  40         info->n_memranges++;
  41     }
  42 }
  43
  44 static int read_lbtable(struct lb_header *head, struct sys_info *info)
  45 {
  46         int retval = 0;
  47
  48         /* Read linuxbios tables... */
  49         struct lb_record *rec;
  50
  51         for_each_lbrec(head, rec) {
  52                 switch(rec->tag) {
  53                 case LB_TAG_MEMORY:
  54                         convert_memmap((struct lb_memory *) rec, info);
  55                         retval = 1;
  56                         break;
  57                 };
  58         }
  59         return retval;
  60 }
  61
  62 static unsigned long count_lb_records(void *start, unsigned long length)
  63 {
  64         struct lb_record *rec;
  65         void *end;
  66         unsigned long count;
  67         count = 0;
  68         end = ((char *)start) + length;
  69         for(rec = start; ((void *)rec < end) &&
  70                 ((signed long)rec->size <=
  71                  ((signed long)end - (signed long)rec));
  72                 rec = (void *)(((char *)rec) + rec->size)) {
  73                 count++;
  74         }
  75         return count;
  76 }
  77
  78 static int find_lb_table(void *start, void *end, struct lb_header **result)
  79 {
  80         unsigned char *ptr;
  81         /* For now be stupid.... */
  82         for(ptr = start; (void *)ptr < end; ptr += 16) {
  83                 struct lb_header *head = (struct lb_header *)ptr;
  84                 if (    (head->signature[0] != 'L') ||
  85                         (head->signature[1] != 'B') ||
  86                         (head->signature[2] != 'I') ||
  87                         (head->signature[3] != 'O')) {
  88                         continue;
  89                 }
  90                 if (head->header_bytes != sizeof(*head))
  91                         continue;
  92                 debug("Found canidate at: %p\n", head);
  93                 if (ipchksum((uint16_t *)head, sizeof(*head)) != 0)
  94                         continue;
  95                 debug("header checksum o.k.\n");
  96                 if (ipchksum((uint16_t *)(ptr + sizeof(*head)), head->table_bytes) !=
  97                         head->table_checksum) {
  98                         continue;
  99                 }
 100                 debug("table checksum o.k.\n");
 101                 if (count_lb_records(ptr + sizeof(*head), head->table_bytes) !=
 102                         head->table_entries) {
 103                         continue;
 104                 }
 105                 debug("record count o.k.\n");
 106                 *result = head;
 107                 return 1;
 108         };
 109         return 0;
 110 }
 111
 112 void collect_linuxbios_info(struct sys_info *info)
 113 {
 114         struct lb_header *lb_table;
 115         int found;
 116         debug("Searching for LinuxBIOS tables...\n");
 117         found = 0;
 118         if (!found) {
 119                 found = find_lb_table(phys_to_virt(0x00000), phys_to_virt(0x01000), &lb_table);
 120         }
 121         if (!found) {
 122                 found = find_lb_table(phys_to_virt(0xf0000), phys_to_virt(0x100000), &lb_table);
 123         }
 124         if (!found)
 125                 return;
 126
 127         debug("Found LinuxBIOS table at: %p\n", lb_table);
 128         info->firmware = "LinuxBIOS";
 129         read_lbtable(lb_table, info);
 130 }