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
35 static inline unsigned long
flat_get_addr_from_rp(unsigned long * rp,unsigned long relval,unsigned long flags,unsigned long * persistent)36 flat_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
65 static inline void
flat_put_addr_at_rp(unsigned long * rp,unsigned long addr,unsigned long relval)66 flat_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