LXR linux/arch/microblaze/include/asm/flat.h

   1/*
   2 * uClinux flat-format executables
   3 *
   4 * Copyright (C) 2005 John Williams <jwilliams@itee.uq.edu.au>
   5 *
   6 * This file is subject to the terms and conditions of the GNU General
   7 * Public License. See the file COPYING in the main directory of this
   8 * archive for more details.
   9 */
  10
  11#ifndef _ASM_MICROBLAZE_FLAT_H
  12#define _ASM_MICROBLAZE_FLAT_H
  13
  14#include <asm/unaligned.h>
  15
  16#define flat_argvp_envp_on_stack()      0
  17#define flat_old_ram_flag(flags)        (flags)
  18#define flat_reloc_valid(reloc, size)   ((reloc) <= (size))
  19#define flat_set_persistent(relval, p)          0
  20
  21/*
  22 * Microblaze works a little differently from other arches, because
  23 * of the MICROBLAZE_64 reloc type. Here, a 32 bit address is split
  24 * over two instructions, an 'imm' instruction which provides the top
  25 * 16 bits, then the instruction "proper" which provides the low 16
  26 * bits.
  27 */
  28
  29/*
  30 * Crack open a symbol reference and extract the address to be
  31 * relocated. rp is a potentially unaligned pointer to the
  32 * reference
  33 */
  34
  35static inline unsigned long
  36flat_get_addr_from_rp(unsigned long *rp, unsigned long relval,
  37                        unsigned long flags, unsigned long *persistent)
  38{
  39        unsigned long addr;
  40        (void)flags;
  41
  42        /* Is it a split 64/32 reference? */
  43        if (relval & 0x80000000) {
  44                /* Grab the two halves of the reference */
  45                unsigned long val_hi, val_lo;
  46
  47                val_hi = get_unaligned(rp);
  48                val_lo = get_unaligned(rp+1);
  49
  50                /* Crack the address out */
  51                addr = ((val_hi & 0xffff) << 16) + (val_lo & 0xffff);
  52        } else {
  53                /* Get the address straight out */
  54                addr = get_unaligned(rp);
  55        }
  56
  57        return addr;
  58}
  59
  60/*
  61 * Insert an address into the symbol reference at rp. rp is potentially
  62 * unaligned.
  63 */
  64
  65static inline void
  66flat_put_addr_at_rp(unsigned long *rp, unsigned long addr, unsigned long relval)
  67{
  68        /* Is this a split 64/32 reloc? */
  69        if (relval & 0x80000000) {
  70                /* Get the two "halves" */
  71                unsigned long val_hi = get_unaligned(rp);
  72                unsigned long val_lo = get_unaligned(rp + 1);
  73
  74                /* insert the address */
  75                val_hi = (val_hi & 0xffff0000) | addr >> 16;
  76                val_lo = (val_lo & 0xffff0000) | (addr & 0xffff);
  77
  78                /* store the two halves back into memory */
  79                put_unaligned(val_hi, rp);
  80                put_unaligned(val_lo, rp+1);
  81        } else {
  82                /* Put it straight in, no messing around */
  83                put_unaligned(addr, rp);
  84        }
  85}
  86
  87#define flat_get_relocate_addr(rel)     (rel & 0x7fffffff)
  88
  89#endif /* _ASM_MICROBLAZE_FLAT_H */
  90