cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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flat.h (1982B)

      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
     27static 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
     55static inline int
     56flat_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 */