grub/lib/mips/relocator.c
Vladimir 'phcoder' Serbinenko badcfeeac0 Fix JUMP_SIZEOF
2009-11-29 12:26:15 +01:00

112 lines
3.6 KiB
C

/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2009 Free Software Foundation, Inc.
*
* GRUB is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* GRUB is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
#include <grub/mm.h>
#include <grub/misc.h>
#include <grub/types.h>
#include <grub/types.h>
#include <grub/err.h>
#include <grub/cache.h>
#include <grub/mips/relocator.h>
/* Remark: doesn't work with source outside of 4G.
Use relocator64 in this case.
*/
extern grub_uint8_t grub_relocator32_forward_start;
extern grub_uint8_t grub_relocator32_forward_end;
extern grub_uint8_t grub_relocator32_backward_start;
extern grub_uint8_t grub_relocator32_backward_end;
#define REGW_SIZEOF (2 * sizeof (grub_uint32_t))
#define JUMP_SIZEOF (2 * sizeof (grub_uint32_t))
#define RELOCATOR_SRC_SIZEOF(x) (&grub_relocator32_##x##_end \
- &grub_relocator32_##x##_start)
#define RELOCATOR_SIZEOF(x) (RELOCATOR_SRC_SIZEOF(x) \
+ REGW_SIZEOF * (31 + 3) + JUMP_SIZEOF)
#define RELOCATOR_ALIGN 16
#define PREFIX(x) grub_relocator32_ ## x
static void
write_reg (int regn, grub_uint32_t val, void **target)
{
/* lui $r, (val+0x8000). */
*(grub_uint32_t *) *target = ((0x3c00 | regn) << 16) | ((val + 0x8000) >> 16);
*target = ((grub_uint32_t *) *target) + 1;
/* addiu $r, $r, val. */
*(grub_uint32_t *) *target = (((0x2400 | regn << 5 | regn) << 16)
| (val & 0xffff));
*target = ((grub_uint32_t *) *target) + 1;
}
static void
write_jump (int regn, void **target)
{
/* j $r. */
*(grub_uint32_t *) *target = (regn<<21) | 0x8;
*target = ((grub_uint32_t *) *target) + 1;
/* nop. */
*(grub_uint32_t *) *target = 0;
*target = ((grub_uint32_t *) *target) + 1;
}
static void
write_call_relocator_bw (void *ptr0, void *src, grub_uint32_t dest,
grub_size_t size, struct grub_relocator32_state state)
{
void *ptr = ptr0;
int i;
write_reg (8, (grub_uint32_t) src, &ptr);
write_reg (9, dest, &ptr);
write_reg (10, size, &ptr);
grub_memcpy (ptr, &grub_relocator32_backward_start,
RELOCATOR_SRC_SIZEOF (backward));
ptr = (grub_uint8_t *) ptr + RELOCATOR_SRC_SIZEOF (backward);
for (i = 1; i < 32; i++)
write_reg (i, state.gpr[i], &ptr);
write_jump (state.jumpreg, &ptr);
grub_arch_sync_caches (ptr0, (grub_uint8_t *) ptr - (grub_uint8_t *) ptr0);
grub_dprintf ("relocator", "Backward relocator: about to jump to %p\n", ptr0);
((void (*) (void)) ptr0) ();
}
static void
write_call_relocator_fw (void *ptr0, void *src, grub_uint32_t dest,
grub_size_t size, struct grub_relocator32_state state)
{
void *ptr = ptr0;
int i;
write_reg (8, (grub_uint32_t) src, &ptr);
write_reg (9, dest, &ptr);
write_reg (10, size, &ptr);
grub_memcpy (ptr, &grub_relocator32_forward_start,
RELOCATOR_SRC_SIZEOF (forward));
ptr = (grub_uint8_t *) ptr + RELOCATOR_SRC_SIZEOF (forward);
for (i = 1; i < 32; i++)
write_reg (i, state.gpr[i], &ptr);
write_jump (state.jumpreg, &ptr);
grub_arch_sync_caches (ptr0, (grub_uint8_t *) ptr - (grub_uint8_t *) ptr0);
grub_dprintf ("relocator", "Forward relocator: about to jump to %p\n", ptr0);
((void (*) (void)) ptr0) ();
}
#include "../relocator.c"