1 /* ----------------------------------------------------------------------- *
2 *
3 * Copyright 2007-2009 H. Peter Anvin - All Rights Reserved
4 * Copyright 2009 Intel Corporation; author: H. Peter Anvin
5 *
6 * Permission is hereby granted, free of charge, to any person
7 * obtaining a copy of this software and associated documentation
8 * files (the "Software"), to deal in the Software without
9 * restriction, including without limitation the rights to use,
10 * copy, modify, merge, publish, distribute, sublicense, and/or
11 * sell copies of the Software, and to permit persons to whom
12 * the Software is furnished to do so, subject to the following
13 * conditions:
14 *
15 * The above copyright notice and this permission notice shall
16 * be included in all copies or substantial portions of the Software.
17 *
18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
19 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
20 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
21 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
22 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
23 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
24 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
25 * OTHER DEALINGS IN THE SOFTWARE.
26 *
27 * ----------------------------------------------------------------------- */
28
29 /*
30 * shuffle_pm.c
31 *
32 * Shuffle and boot to protected mode code
33 */
34
35 #include <inttypes.h>
36 #include <syslinux/movebits.h>
37 #include <syslinux/bootpm.h>
38
syslinux_shuffle_boot_pm(struct syslinux_movelist * fraglist,struct syslinux_memmap * memmap,uint16_t bootflags,struct syslinux_pm_regs * regs)39 int syslinux_shuffle_boot_pm(struct syslinux_movelist *fraglist,
40 struct syslinux_memmap *memmap,
41 uint16_t bootflags, struct syslinux_pm_regs *regs)
42 {
43 uint8_t handoff_code[9 * 5], *p;
44 const uint32_t *rp;
45 int i, rv;
46 struct syslinux_memmap *tmap;
47 addr_t regstub, stublen;
48
49 tmap = syslinux_target_memmap(fraglist, memmap);
50 if (!tmap)
51 return -1;
52
53 regstub = 0x800; /* Locate anywhere above this point */
54 stublen = sizeof handoff_code;
55 rv = syslinux_memmap_find_type(tmap, SMT_FREE, ®stub, &stublen, 1);
56 syslinux_free_memmap(tmap);
57 if (rv)
58 return -1;
59
60 /* Build register-setting stub */
61 p = handoff_code;
62 rp = (const uint32_t *)regs;
63 for (i = 0; i < 8; i++) {
64 *p = 0xb8 + i; /* MOV gpr,imm32 */
65 *(uint32_t *) (p + 1) = *rp++;
66 p += 5;
67 }
68 *p = 0xe9; /* JMP */
69 *(uint32_t *) (p + 1) = regs->eip - regstub - sizeof handoff_code;
70
71 /* Add register-setting stub to shuffle list */
72 if (syslinux_add_movelist(&fraglist, regstub, (addr_t) handoff_code,
73 sizeof handoff_code))
74 return -1;
75
76 return syslinux_do_shuffle(fraglist, memmap, regstub, 1, bootflags);
77 }
78