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