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 /* 17 * Microblaze works a little differently from other arches, because 18 * of the MICROBLAZE_64 reloc type. Here, a 32 bit address is split 19 * over two instructions, an 'imm' instruction which provides the top 20 * 16 bits, then the instruction "proper" which provides the low 16 21 * bits. 22 */ 23 24 /* 25 * Crack open a symbol reference and extract the address to be 26 * relocated. rp is a potentially unaligned pointer to the 27 * reference 28 */ 29 30 static inline int flat_get_addr_from_rp(u32 __user *rp, u32 relval, u32 flags, 31 u32 *addr) 32 { 33 u32 *p = (__force u32 *)rp; 34 35 /* Is it a split 64/32 reference? */ 36 if (relval & 0x80000000) { 37 /* Grab the two halves of the reference */ 38 u32 val_hi, val_lo; 39 40 val_hi = get_unaligned(p); 41 val_lo = get_unaligned(p+1); 42 43 /* Crack the address out */ 44 *addr = ((val_hi & 0xffff) << 16) + (val_lo & 0xffff); 45 } else { 46 /* Get the address straight out */ 47 *addr = get_unaligned(p); 48 } 49 50 return 0; 51 } 52 53 /* 54 * Insert an address into the symbol reference at rp. rp is potentially 55 * unaligned. 56 */ 57 58 static inline int 59 flat_put_addr_at_rp(u32 __user *rp, u32 addr, u32 relval) 60 { 61 u32 *p = (__force u32 *)rp; 62 /* Is this a split 64/32 reloc? */ 63 if (relval & 0x80000000) { 64 /* Get the two "halves" */ 65 unsigned long val_hi = get_unaligned(p); 66 unsigned long val_lo = get_unaligned(p + 1); 67 68 /* insert the address */ 69 val_hi = (val_hi & 0xffff0000) | addr >> 16; 70 val_lo = (val_lo & 0xffff0000) | (addr & 0xffff); 71 72 /* store the two halves back into memory */ 73 put_unaligned(val_hi, p); 74 put_unaligned(val_lo, p+1); 75 } else { 76 /* Put it straight in, no messing around */ 77 put_unaligned(addr, p); 78 } 79 return 0; 80 } 81 82 #define flat_get_relocate_addr(rel) (rel & 0x7fffffff) 83 84 #endif /* _ASM_MICROBLAZE_FLAT_H */ 85