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_stack_align(sp) /* nothing needed */ 17 #define flat_argvp_envp_on_stack() 0 18 #define flat_old_ram_flag(flags) (flags) 19 #define flat_reloc_valid(reloc, size) ((reloc) <= (size)) 20 #define flat_set_persistent(relval, p) 0 21 22 /* 23 * Microblaze works a little differently from other arches, because 24 * of the MICROBLAZE_64 reloc type. Here, a 32 bit address is split 25 * over two instructions, an 'imm' instruction which provides the top 26 * 16 bits, then the instruction "proper" which provides the low 16 27 * bits. 28 */ 29 30 /* 31 * Crack open a symbol reference and extract the address to be 32 * relocated. rp is a potentially unaligned pointer to the 33 * reference 34 */ 35 36 static inline unsigned long 37 flat_get_addr_from_rp(unsigned long *rp, unsigned long relval, 38 unsigned long flags, unsigned long *persistent) 39 { 40 unsigned long addr; 41 (void)flags; 42 43 /* Is it a split 64/32 reference? */ 44 if (relval & 0x80000000) { 45 /* Grab the two halves of the reference */ 46 unsigned long val_hi, val_lo; 47 48 val_hi = get_unaligned(rp); 49 val_lo = get_unaligned(rp+1); 50 51 /* Crack the address out */ 52 addr = ((val_hi & 0xffff) << 16) + (val_lo & 0xffff); 53 } else { 54 /* Get the address straight out */ 55 addr = get_unaligned(rp); 56 } 57 58 return addr; 59 } 60 61 /* 62 * Insert an address into the symbol reference at rp. rp is potentially 63 * unaligned. 64 */ 65 66 static inline void 67 flat_put_addr_at_rp(unsigned long *rp, unsigned long addr, unsigned long relval) 68 { 69 /* Is this a split 64/32 reloc? */ 70 if (relval & 0x80000000) { 71 /* Get the two "halves" */ 72 unsigned long val_hi = get_unaligned(rp); 73 unsigned long val_lo = get_unaligned(rp + 1); 74 75 /* insert the address */ 76 val_hi = (val_hi & 0xffff0000) | addr >> 16; 77 val_lo = (val_lo & 0xffff0000) | (addr & 0xffff); 78 79 /* store the two halves back into memory */ 80 put_unaligned(val_hi, rp); 81 put_unaligned(val_lo, rp+1); 82 } else { 83 /* Put it straight in, no messing around */ 84 put_unaligned(addr, rp); 85 } 86 } 87 88 #define flat_get_relocate_addr(rel) (rel & 0x7fffffff) 89 90 #endif /* _ASM_MICROBLAZE_FLAT_H */ 91