1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * uClinux flat-format executables 4 * 5 * Copyright (C) 2005 John Williams <jwilliams@itee.uq.edu.au> 6 */ 7 8 #ifndef _ASM_MICROBLAZE_FLAT_H 9 #define _ASM_MICROBLAZE_FLAT_H 10 11 #include <asm/unaligned.h> 12 13 /* 14 * Microblaze works a little differently from other arches, because 15 * of the MICROBLAZE_64 reloc type. Here, a 32 bit address is split 16 * over two instructions, an 'imm' instruction which provides the top 17 * 16 bits, then the instruction "proper" which provides the low 16 18 * bits. 19 */ 20 21 /* 22 * Crack open a symbol reference and extract the address to be 23 * relocated. rp is a potentially unaligned pointer to the 24 * reference 25 */ 26 27 static inline int flat_get_addr_from_rp(u32 __user *rp, u32 relval, u32 flags, 28 u32 *addr) 29 { 30 u32 *p = (__force u32 *)rp; 31 32 /* Is it a split 64/32 reference? */ 33 if (relval & 0x80000000) { 34 /* Grab the two halves of the reference */ 35 u32 val_hi, val_lo; 36 37 val_hi = get_unaligned(p); 38 val_lo = get_unaligned(p+1); 39 40 /* Crack the address out */ 41 *addr = ((val_hi & 0xffff) << 16) + (val_lo & 0xffff); 42 } else { 43 /* Get the address straight out */ 44 *addr = get_unaligned(p); 45 } 46 47 return 0; 48 } 49 50 /* 51 * Insert an address into the symbol reference at rp. rp is potentially 52 * unaligned. 53 */ 54 55 static inline int 56 flat_put_addr_at_rp(u32 __user *rp, u32 addr, u32 relval) 57 { 58 u32 *p = (__force u32 *)rp; 59 /* Is this a split 64/32 reloc? */ 60 if (relval & 0x80000000) { 61 /* Get the two "halves" */ 62 unsigned long val_hi = get_unaligned(p); 63 unsigned long val_lo = get_unaligned(p + 1); 64 65 /* insert the address */ 66 val_hi = (val_hi & 0xffff0000) | addr >> 16; 67 val_lo = (val_lo & 0xffff0000) | (addr & 0xffff); 68 69 /* store the two halves back into memory */ 70 put_unaligned(val_hi, p); 71 put_unaligned(val_lo, p+1); 72 } else { 73 /* Put it straight in, no messing around */ 74 put_unaligned(addr, p); 75 } 76 return 0; 77 } 78 79 #define flat_get_relocate_addr(rel) (rel & 0x7fffffff) 80 81 #endif /* _ASM_MICROBLAZE_FLAT_H */ 82