1 /* Copyright (C) 2008 Michael Brown <mbrown@fensystems.co.uk>.
3 * This program is free software; you can redistribute it and/or
4 * modify it under the terms of the GNU General Public License as
5 * published by the Free Software Foundation; either version 2 of the
6 * License, or any later version.
8 * This program is distributed in the hope that it will be useful, but
9 * WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
11 * General Public License for more details.
13 * You should have received a copy of the GNU General Public License
14 * along with this program; if not, write to the Free Software
15 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
18 * You can also choose to distribute this program under the terms of
19 * the Unmodified Binary Distribution Licence (as given in the file
20 * COPYING.UBDL), provided that you have satisfied its requirements.
23 FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
28 /** Assembly routine in inline asm */
29 extern void int15_fakee820();
31 /** Original INT 15 handler */
32 static struct segoff __text16 ( real_int15_vector );
33 #define real_int15_vector __use_text16 ( real_int15_vector )
35 /** An INT 15,e820 memory map entry */
37 /** Start of region */
39 /** Length of region */
43 } __attribute__ (( packed ));
45 #define E820_TYPE_RAM 1 /**< Normal memory */
46 #define E820_TYPE_RSVD 2 /**< Reserved and unavailable */
47 #define E820_TYPE_ACPI 3 /**< ACPI reclaim memory */
48 #define E820_TYPE_NVS 4 /**< ACPI NVS memory */
51 static struct e820_entry __text16_array ( e820map, [] ) __used = {
52 { 0x00000000ULL, ( 0x000a0000ULL - 0x00000000ULL ), E820_TYPE_RAM },
53 { 0x00100000ULL, ( 0xcfb50000ULL - 0x00100000ULL ), E820_TYPE_RAM },
54 { 0xcfb50000ULL, ( 0xcfb64000ULL - 0xcfb50000ULL ), E820_TYPE_RSVD },
55 { 0xcfb64000ULL, ( 0xcfb66000ULL - 0xcfb64000ULL ), E820_TYPE_RSVD },
56 { 0xcfb66000ULL, ( 0xcfb85c00ULL - 0xcfb66000ULL ), E820_TYPE_ACPI },
57 { 0xcfb85c00ULL, ( 0xd0000000ULL - 0xcfb85c00ULL ), E820_TYPE_RSVD },
58 { 0xe0000000ULL, ( 0xf0000000ULL - 0xe0000000ULL ), E820_TYPE_RSVD },
59 { 0xfe000000ULL, (0x100000000ULL - 0xfe000000ULL ), E820_TYPE_RSVD },
60 {0x100000000ULL, (0x230000000ULL -0x100000000ULL ), E820_TYPE_RAM },
62 #define e820map __use_text16 ( e820map )
64 void fake_e820 ( void ) {
65 __asm__ __volatile__ (
66 TEXT16_CODE ( "\nint15_fakee820:\n\t"
68 "cmpl $0xe820, %%eax\n\t"
70 "cmpl $0x534d4150, %%edx\n\t"
74 "andb $~0x01, 22(%%bp)\n\t" /* Clear return CF */
75 "leaw e820map(%%bx), %%si\n\t"
78 "movl %%edx, %%eax\n\t"
82 "xorl %%ebx,%%ebx\n\t"
88 "ljmp *%%cs:real_int15_vector\n\t" )
89 : : "i" ( sizeof ( e820map ) ) );
91 hook_bios_interrupt ( 0x15, ( unsigned int ) int15_fakee820,
95 void unfake_e820 ( void ) {
96 unhook_bios_interrupt ( 0x15, ( unsigned int ) int15_fakee820,