arch/m68k-all/dosboot/bootcode.c

   1 #include <aros/debug.h>
   2 #include <libraries/configvars.h>
   3 #include <libraries/expansion.h>
   4 #include <libraries/expansionbase.h>
   5 #include <utility/tagitem.h>
   6 #include <dos/filehandler.h>
   7
   8 #include <proto/exec.h>
   9
  10 /*
  11  * Execute the code in the boot block.
  12  * This can be custom defined for your architecture.
  13  *
  14  * Returns 0 on success, or an error code
  15  */
  16 VOID_FUNC CallBootBlockCode(APTR bootcode, struct IOStdReq *io, struct ExpansionBase *ExpansionBase)
  17 {
  18     UBYTE oldflags = ExpansionBase->Flags & EBF_SILENTSTART;
  19     LONG retval;
  20     VOID_FUNC init;
  21
  22     D(bug("[Strap] Calling bootblock 0x%p!\n", bootcode));
  23
  24     ExpansionBase->Flags &= ~EBF_SILENTSTART;
  25
  26     /* Lovely. Double return values. What func. */
  27     asm volatile (
  28                  "move.l %2,%%a1\n"
  29                  "move.l %4,%%a0\n"
  30                  "move.l %%a6,%%sp@-\n"
  31                  "move.l %3,%%a6\n"
  32                  "jsr.l (%%a0)\n"
  33                  "move.l %%sp@+,%%a6\n"
  34                  "move.l %%d0,%0\n"
  35                  "move.l %%a0,%1\n"
  36                  : "=m" (retval), "=m" (init)
  37                  : "m" (io), "r" (SysBase),
  38                    "m" (bootcode)
  39                  : "%d0", "%d1", "%a0", "%a1");
  40     D(bug("bootblock: D0=0x%08x A0=%p\n", retval, init));
  41
  42     if (retval != 0)
  43     {
  44         D(bug("[Strap] Boot block failed to boot.\n"));
  45
  46         ExpansionBase->Flags |= oldflags;
  47         return NULL;
  48     }
  49
  50     return init;
  51 }
  52
  53 /* BootPoint booting, as describe in the Amiga Devices Manual */
  54 void dosboot_BootPoint(struct BootNode *bn)
  55 {
  56     struct DeviceNode *dn;
  57     struct FileSysStartupMsg *fssm;
  58     struct DosEnvec *de;
  59     IPTR bootblocks;
  60
  61     dn = bn->bn_DeviceNode;
  62     if (dn == NULL || dn->dn_Name == BNULL)
  63         return;
  64
  65     fssm = BADDR(dn->dn_Startup);
  66     if (fssm == NULL)
  67         return;
  68
  69     de = BADDR(fssm->fssm_Environ);
  70     if (de == NULL)
  71         return;
  72
  73     bootblocks = (de->de_TableSize < DE_BOOTBLOCKS) ? 0 : de->de_BootBlocks;
  74
  75     /* BootPoint nodes */
  76     if (bootblocks == 0 && bn->bn_Node.ln_Name != NULL)
  77     {
  78         struct ConfigDev *cd = (APTR)bn->bn_Node.ln_Name;
  79
  80         if (cd->cd_Rom.er_DiagArea != NULL)
  81         {
  82             struct DiagArea *da = cd->cd_Rom.er_DiagArea;
  83
  84             if (da->da_Config & DAC_CONFIGTIME)
  85             {
  86                 /* Yes, it's actually a BootPoint node */
  87                 void *func = (APTR)(((IPTR)da) + da->da_BootPoint);
  88
  89                 D(bug("dosboot_BootStrap: Calling %b BootPoint @%p\n", dn->dn_Name, func));
  90
  91                 /*
  92                  * Yet another crazy Amiga calling sequence.
  93                  * The ConfigDev is pushed on the stack, but
  94                  * the BootNode is in A2. Joy.
  95                  *
  96                  * Oh, and don't forget SysBase in A6!
  97                  */
  98                 asm volatile (
  99                         "move.l %0,%%a0\n"
 100                         "move.l %1,%%a1\n"
 101                         "move.l %2,%%a2\n"
 102                         "move.l %3,%%a6\n"
 103                         "move.l %%a1,%%sp@-\n"
 104                         "jsr    %%a0@\n"
 105                         "addq.l #4,%%sp\n"
 106                         :
 107                         : "d" (func), "d" (cd), "d" (bn), "d" (SysBase)
 108                         : "d0", "d1", "a0", "a1", "a2", "a6"
 109                         );
 110             }
 111         }
 112     }
 113 }