err.no Git - linux-2.6/blob - arch/sparc/prom/memory.c

   1 /* memory.c: Prom routine for acquiring various bits of information
   2  *           about RAM on the machine, both virtual and physical.
   3  *
   4  * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
   5  * Copyright (C) 1997 Michael A. Griffith (grif@acm.org)
   6  */
   7
   8 #include <linux/kernel.h>
   9 #include <linux/init.h>
  10
  11 #include <asm/openprom.h>
  12 #include <asm/sun4prom.h>
  13 #include <asm/oplib.h>
  14
  15 /* This routine, for consistency, returns the ram parameters in the
  16  * V0 prom memory descriptor format.  I choose this format because I
  17  * think it was the easiest to work with.  I feel the religious
  18  * arguments now... ;)  Also, I return the linked lists sorted to
  19  * prevent paging_init() upset stomach as I have not yet written
  20  * the pepto-bismol kernel module yet.
  21  */
  22
  23 struct linux_prom_registers prom_reg_memlist[64];
  24
  25 struct linux_mlist_v0 prom_phys_avail[64];
  26
  27 /* Internal Prom library routine to sort a linux_mlist_v0 memory
  28  * list.  Used below in initialization.
  29  */
  30 static void __init
  31 prom_sortmemlist(struct linux_mlist_v0 *thislist)
  32 {
  33         int swapi = 0;
  34         int i, mitr, tmpsize;
  35         char *tmpaddr;
  36         char *lowest;
  37
  38         for(i=0; thislist[i].theres_more; i++) {
  39                 lowest = thislist[i].start_adr;
  40                 for(mitr = i+1; thislist[mitr-1].theres_more; mitr++)
  41                         if(thislist[mitr].start_adr < lowest) {
  42                                 lowest = thislist[mitr].start_adr;
  43                                 swapi = mitr;
  44                         }
  45                 if(lowest == thislist[i].start_adr) continue;
  46                 tmpaddr = thislist[swapi].start_adr;
  47                 tmpsize = thislist[swapi].num_bytes;
  48                 for(mitr = swapi; mitr > i; mitr--) {
  49                         thislist[mitr].start_adr = thislist[mitr-1].start_adr;
  50                         thislist[mitr].num_bytes = thislist[mitr-1].num_bytes;
  51                 }
  52                 thislist[i].start_adr = tmpaddr;
  53                 thislist[i].num_bytes = tmpsize;
  54         }
  55
  56         return;
  57 }
  58
  59 /* Initialize the memory lists based upon the prom version. */
  60 void __init prom_meminit(void)
  61 {
  62         int node = 0;
  63         unsigned int iter, num_regs;
  64         struct linux_mlist_v0 *mptr;  /* ptr for traversal */
  65
  66         switch(prom_vers) {
  67         case PROM_V0:
  68                 /* Nice, kind of easier to do in this case. */
  69                 for(mptr = (*(romvec->pv_v0mem.v0_available)), iter=0;
  70                     mptr; mptr=mptr->theres_more, iter++) {
  71                         prom_phys_avail[iter].start_adr = mptr->start_adr;
  72                         prom_phys_avail[iter].num_bytes = mptr->num_bytes;
  73                         prom_phys_avail[iter].theres_more = &prom_phys_avail[iter+1];
  74                 }
  75                 prom_phys_avail[iter-1].theres_more = NULL;
  76                 prom_sortmemlist(prom_phys_avail);
  77                 break;
  78         case PROM_V2:
  79         case PROM_V3:
  80                 /* Grrr, have to traverse the prom device tree ;( */
  81                 node = prom_getchild(prom_root_node);
  82                 node = prom_searchsiblings(node, "memory");
  83                 num_regs = prom_getproperty(node, "available",
  84                                             (char *) prom_reg_memlist,
  85                                             sizeof(prom_reg_memlist));
  86                 num_regs = (num_regs/sizeof(struct linux_prom_registers));
  87                 for(iter=0; iter<num_regs; iter++) {
  88                         prom_phys_avail[iter].start_adr =
  89                                 (char *) prom_reg_memlist[iter].phys_addr;
  90                         prom_phys_avail[iter].num_bytes =
  91                                 (unsigned long) prom_reg_memlist[iter].reg_size;
  92                         prom_phys_avail[iter].theres_more =
  93                                 &prom_phys_avail[iter+1];
  94                 }
  95                 prom_phys_avail[iter-1].theres_more = NULL;
  96                 prom_sortmemlist(prom_phys_avail);
  97                 break;
  98
  99         case PROM_SUN4:
 100 #ifdef CONFIG_SUN4
 101                 /* how simple :) */
 102                 prom_phys_avail[0].start_adr = NULL;
 103                 prom_phys_avail[0].num_bytes = *(sun4_romvec->memoryavail);
 104                 prom_phys_avail[0].theres_more = NULL;
 105 #endif
 106                 break;
 107
 108         default:
 109                 break;
 110         };
 111 }
 112
 113 /* This returns a pointer to our libraries internal v0 format
 114  * available memory list.
 115  */
 116 struct linux_mlist_v0 *
 117 prom_meminfo(void)
 118 {
 119         return prom_phys_avail;
 120 }