1 /*
2 * arch/blackfin/kernel/flat.c
3 *
4 * Copyright (C) 2007 Analog Devices, Inc.
5 *
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
10 *
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
15 *
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 */
20
21 #include <linux/module.h>
22 #include <linux/sched.h>
23 #include <linux/flat.h>
24
25 #define FLAT_BFIN_RELOC_TYPE_16_BIT 0
26 #define FLAT_BFIN_RELOC_TYPE_16H_BIT 1
27 #define FLAT_BFIN_RELOC_TYPE_32_BIT 2
28
bfin_get_addr_from_rp(unsigned long * ptr,unsigned long relval,unsigned long flags,unsigned long * persistent)29 unsigned long bfin_get_addr_from_rp(unsigned long *ptr,
30 unsigned long relval,
31 unsigned long flags,
32 unsigned long *persistent)
33 {
34 unsigned short *usptr = (unsigned short *)ptr;
35 int type = (relval >> 26) & 7;
36 unsigned long val;
37
38 switch (type) {
39 case FLAT_BFIN_RELOC_TYPE_16_BIT:
40 case FLAT_BFIN_RELOC_TYPE_16H_BIT:
41 usptr = (unsigned short *)ptr;
42 pr_debug("*usptr = %x", get_unaligned(usptr));
43 val = get_unaligned(usptr);
44 val += *persistent;
45 break;
46
47 case FLAT_BFIN_RELOC_TYPE_32_BIT:
48 pr_debug("*ptr = %lx", get_unaligned(ptr));
49 val = get_unaligned(ptr);
50 break;
51
52 default:
53 pr_debug("BINFMT_FLAT: Unknown relocation type %x\n", type);
54 return 0;
55 }
56
57 /*
58 * Stack-relative relocs contain the offset into the stack, we
59 * have to add the stack's start address here and return 1 from
60 * flat_addr_absolute to prevent the normal address calculations
61 */
62 if (relval & (1 << 29))
63 return val + current->mm->context.end_brk;
64
65 if ((flags & FLAT_FLAG_GOTPIC) == 0)
66 val = htonl(val);
67 return val;
68 }
69 EXPORT_SYMBOL(bfin_get_addr_from_rp);
70
71 /*
72 * Insert the address ADDR into the symbol reference at RP;
73 * RELVAL is the raw relocation-table entry from which RP is derived
74 */
bfin_put_addr_at_rp(unsigned long * ptr,unsigned long addr,unsigned long relval)75 void bfin_put_addr_at_rp(unsigned long *ptr, unsigned long addr,
76 unsigned long relval)
77 {
78 unsigned short *usptr = (unsigned short *)ptr;
79 int type = (relval >> 26) & 7;
80
81 switch (type) {
82 case FLAT_BFIN_RELOC_TYPE_16_BIT:
83 put_unaligned(addr, usptr);
84 pr_debug("new value %x at %p", get_unaligned(usptr), usptr);
85 break;
86
87 case FLAT_BFIN_RELOC_TYPE_16H_BIT:
88 put_unaligned(addr >> 16, usptr);
89 pr_debug("new value %x", get_unaligned(usptr));
90 break;
91
92 case FLAT_BFIN_RELOC_TYPE_32_BIT:
93 put_unaligned(addr, ptr);
94 pr_debug("new ptr =%lx", get_unaligned(ptr));
95 break;
96 }
97 }
98 EXPORT_SYMBOL(bfin_put_addr_at_rp);
99