kernel/arch/microblaze/include/asm/flat.h
2024-07-22 17:22:30 +08:00

82 lines
1.9 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/*
* uClinux flat-format executables
*
* Copyright (C) 2005 John Williams <jwilliams@itee.uq.edu.au>
*/
#ifndef _ASM_MICROBLAZE_FLAT_H
#define _ASM_MICROBLAZE_FLAT_H
#include <asm/unaligned.h>
/*
* Microblaze works a little differently from other arches, because
* of the MICROBLAZE_64 reloc type. Here, a 32 bit address is split
* over two instructions, an 'imm' instruction which provides the top
* 16 bits, then the instruction "proper" which provides the low 16
* bits.
*/
/*
* Crack open a symbol reference and extract the address to be
* relocated. rp is a potentially unaligned pointer to the
* reference
*/
static inline int flat_get_addr_from_rp(u32 __user *rp, u32 relval, u32 flags,
u32 *addr)
{
u32 *p = (__force u32 *)rp;
/* Is it a split 64/32 reference? */
if (relval & 0x80000000) {
/* Grab the two halves of the reference */
u32 val_hi, val_lo;
val_hi = get_unaligned(p);
val_lo = get_unaligned(p+1);
/* Crack the address out */
*addr = ((val_hi & 0xffff) << 16) + (val_lo & 0xffff);
} else {
/* Get the address straight out */
*addr = get_unaligned(p);
}
return 0;
}
/*
* Insert an address into the symbol reference at rp. rp is potentially
* unaligned.
*/
static inline int
flat_put_addr_at_rp(u32 __user *rp, u32 addr, u32 relval)
{
u32 *p = (__force u32 *)rp;
/* Is this a split 64/32 reloc? */
if (relval & 0x80000000) {
/* Get the two "halves" */
unsigned long val_hi = get_unaligned(p);
unsigned long val_lo = get_unaligned(p + 1);
/* insert the address */
val_hi = (val_hi & 0xffff0000) | addr >> 16;
val_lo = (val_lo & 0xffff0000) | (addr & 0xffff);
/* store the two halves back into memory */
put_unaligned(val_hi, p);
put_unaligned(val_lo, p+1);
} else {
/* Put it straight in, no messing around */
put_unaligned(addr, p);
}
return 0;
}
#define flat_get_relocate_addr(rel) (rel & 0x7fffffff)
#endif /* _ASM_MICROBLAZE_FLAT_H */