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/flat.h>
  10
  11 #define FLAT_BFIN_RELOC_TYPE_16_BIT 0
  12 #define FLAT_BFIN_RELOC_TYPE_16H_BIT 1
  13 #define FLAT_BFIN_RELOC_TYPE_32_BIT 2
  14
  15 unsigned long bfin_get_addr_from_rp(unsigned long *ptr,
  16                 unsigned long relval,
  17                 unsigned long flags,
  18                 unsigned long *persistent)
  19 {
  20         unsigned short *usptr = (unsigned short *)ptr;
  21         int type = (relval >> 26) & 7;
  22         unsigned long val;
  23
  24         switch (type) {
  25         case FLAT_BFIN_RELOC_TYPE_16_BIT:
  26         case FLAT_BFIN_RELOC_TYPE_16H_BIT:
  27                 usptr = (unsigned short *)ptr;
  28                 pr_debug("*usptr = %x", get_unaligned(usptr));
  29                 val = get_unaligned(usptr);
  30                 val += *persistent;
  31                 break;
  32
  33         case FLAT_BFIN_RELOC_TYPE_32_BIT:
  34                 pr_debug("*ptr = %lx", get_unaligned(ptr));
  35                 val = get_unaligned(ptr);
  36                 break;
  37
  38         default:
  39                 pr_debug("BINFMT_FLAT: Unknown relocation type %x\n", type);
  40                 return 0;
  41         }
  42
  43         /*
  44          * Stack-relative relocs contain the offset into the stack, we
  45          * have to add the stack's start address here and return 1 from
  46          * flat_addr_absolute to prevent the normal address calculations
  47          */
  48         if (relval & (1 << 29))
  49                 return val + current->mm->context.end_brk;
  50
  51         if ((flags & FLAT_FLAG_GOTPIC) == 0)
  52                 val = htonl(val);
  53         return val;
  54 }
  55 EXPORT_SYMBOL(bfin_get_addr_from_rp);
  56
  57 /*
  58  * Insert the address ADDR into the symbol reference at RP;
  59  * RELVAL is the raw relocation-table entry from which RP is derived
  60  */
  61 void bfin_put_addr_at_rp(unsigned long *ptr, unsigned long addr,
  62                 unsigned long 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 =%lx", get_unaligned(ptr));
  81                 break;
  82         }
  83 }
  84 EXPORT_SYMBOL(bfin_put_addr_at_rp);