arch/blackfin/kernel/flat.c

   1 /*
   2  * Copyright 2007 Analog Devices Inc.
   3  *
   4  * Licensed under the GPL-2.
   5  */
   6
   7 #include <linux/module.h>
   8 #include <linux/sched.h>
   9 #include <linux/mm_types.h>
  10 #include <linux/flat.h>
  11
  12 #define FLAT_BFIN_RELOC_TYPE_16_BIT 0
  13 #define FLAT_BFIN_RELOC_TYPE_16H_BIT 1
  14 #define FLAT_BFIN_RELOC_TYPE_32_BIT 2
  15
  16 unsigned long bfin_get_addr_from_rp(u32 *ptr,
  17                 u32 relval,
  18                 u32 flags,
  19                 u32 *persistent)
  20 {
  21         unsigned short *usptr = (unsigned short *)ptr;
  22         int type = (relval >> 26) & 7;
  23         u32 val;
  24
  25         switch (type) {
  26         case FLAT_BFIN_RELOC_TYPE_16_BIT:
  27         case FLAT_BFIN_RELOC_TYPE_16H_BIT:
  28                 usptr = (unsigned short *)ptr;
  29                 pr_debug("*usptr = %x", get_unaligned(usptr));
  30                 val = get_unaligned(usptr);
  31                 val += *persistent;
  32                 break;
  33
  34         case FLAT_BFIN_RELOC_TYPE_32_BIT:
  35                 pr_debug("*ptr = %x", get_unaligned(ptr));
  36                 val = get_unaligned(ptr);
  37                 break;
  38
  39         default:
  40                 pr_debug("BINFMT_FLAT: Unknown relocation type %x\n", type);
  41                 return 0;
  42         }
  43
  44         /*
  45          * Stack-relative relocs contain the offset into the stack, we
  46          * have to add the stack's start address here and return 1 from
  47          * flat_addr_absolute to prevent the normal address calculations
  48          */
  49         if (relval & (1 << 29))
  50                 return val + current->mm->context.end_brk;
  51
  52         if ((flags & FLAT_FLAG_GOTPIC) == 0)
  53                 val = htonl(val);
  54         return val;
  55 }
  56 EXPORT_SYMBOL(bfin_get_addr_from_rp);
  57
  58 /*
  59  * Insert the address ADDR into the symbol reference at RP;
  60  * RELVAL is the raw relocation-table entry from which RP is derived
  61  */
  62 void bfin_put_addr_at_rp(u32 *ptr, u32 addr, u32 relval)
  63 {
  64         unsigned short *usptr = (unsigned short *)ptr;
  65         int type = (relval >> 26) & 7;
  66
  67         switch (type) {
  68         case FLAT_BFIN_RELOC_TYPE_16_BIT:
  69                 put_unaligned(addr, usptr);
  70                 pr_debug("new value %x at %p", get_unaligned(usptr), usptr);
  71                 break;
  72
  73         case FLAT_BFIN_RELOC_TYPE_16H_BIT:
  74                 put_unaligned(addr >> 16, usptr);
  75                 pr_debug("new value %x", get_unaligned(usptr));
  76                 break;
  77
  78         case FLAT_BFIN_RELOC_TYPE_32_BIT:
  79                 put_unaligned(addr, ptr);
  80                 pr_debug("new ptr =%x", get_unaligned(ptr));
  81                 break;
  82         }
  83 }
  84 EXPORT_SYMBOL(bfin_put_addr_at_rp);