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authorThomas Gleixner <tglx@linutronix.de>2007-10-11 05:16:45 -0400
committerThomas Gleixner <tglx@linutronix.de>2007-10-11 05:16:45 -0400
commit96ae6ea0be1b902c28b3b463c27da42b41e2b63a (patch)
treefbc18761d4fa93d7b0f6dbf3496289fa32bd363a /arch/x86/boot/apm.c
parent0530bf37cebcf22a73652937c2340bc1ebd92000 (diff)
i386: move boot
Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/boot/apm.c')
-rw-r--r--arch/x86/boot/apm.c98
1 files changed, 98 insertions, 0 deletions
diff --git a/arch/x86/boot/apm.c b/arch/x86/boot/apm.c
new file mode 100644
index 000000000000..eab50c55a3a5
--- /dev/null
+++ b/arch/x86/boot/apm.c
@@ -0,0 +1,98 @@
1/* -*- linux-c -*- ------------------------------------------------------- *
2 *
3 * Copyright (C) 1991, 1992 Linus Torvalds
4 * Copyright 2007 rPath, Inc. - All Rights Reserved
5 *
6 * Original APM BIOS checking by Stephen Rothwell, May 1994
7 * (sfr@canb.auug.org.au)
8 *
9 * This file is part of the Linux kernel, and is made available under
10 * the terms of the GNU General Public License version 2.
11 *
12 * ----------------------------------------------------------------------- */
13
14/*
15 * arch/i386/boot/apm.c
16 *
17 * Get APM BIOS information
18 */
19
20#include "boot.h"
21
22#if defined(CONFIG_APM) || defined(CONFIG_APM_MODULE)
23
24int query_apm_bios(void)
25{
26 u16 ax, bx, cx, dx, di;
27 u32 ebx, esi;
28 u8 err;
29
30 /* APM BIOS installation check */
31 ax = 0x5300;
32 bx = cx = 0;
33 asm volatile("pushl %%ebp ; int $0x15 ; popl %%ebp ; setc %0"
34 : "=d" (err), "+a" (ax), "+b" (bx), "+c" (cx)
35 : : "esi", "edi");
36
37 if (err)
38 return -1; /* No APM BIOS */
39
40 if (bx != 0x504d) /* "PM" signature */
41 return -1;
42
43 if (!(cx & 0x02)) /* 32 bits supported? */
44 return -1;
45
46 /* Disconnect first, just in case */
47 ax = 0x5304;
48 bx = 0;
49 asm volatile("pushl %%ebp ; int $0x15 ; popl %%ebp"
50 : "+a" (ax), "+b" (bx)
51 : : "ecx", "edx", "esi", "edi");
52
53 /* Paranoia */
54 ebx = esi = 0;
55 cx = dx = di = 0;
56
57 /* 32-bit connect */
58 asm volatile("pushl %%ebp ; int $0x15 ; popl %%ebp ; setc %6"
59 : "=a" (ax), "+b" (ebx), "+c" (cx), "+d" (dx),
60 "+S" (esi), "+D" (di), "=m" (err)
61 : "a" (0x5303));
62
63 boot_params.apm_bios_info.cseg = ax;
64 boot_params.apm_bios_info.offset = ebx;
65 boot_params.apm_bios_info.cseg_16 = cx;
66 boot_params.apm_bios_info.dseg = dx;
67 boot_params.apm_bios_info.cseg_len = (u16)esi;
68 boot_params.apm_bios_info.cseg_16_len = esi >> 16;
69 boot_params.apm_bios_info.dseg_len = di;
70
71 if (err)
72 return -1;
73
74 /* Redo the installation check as the 32-bit connect;
75 some BIOSes return different flags this way... */
76
77 ax = 0x5300;
78 bx = cx = 0;
79 asm volatile("pushl %%ebp ; int $0x15 ; popl %%ebp ; setc %0"
80 : "=d" (err), "+a" (ax), "+b" (bx), "+c" (cx)
81 : : "esi", "edi");
82
83 if (err || bx != 0x504d) {
84 /* Failure with 32-bit connect, try to disconect and ignore */
85 ax = 0x5304;
86 bx = 0;
87 asm volatile("pushl %%ebp ; int $0x15 ; popl %%ebp"
88 : "+a" (ax), "+b" (bx)
89 : : "ecx", "edx", "esi", "edi");
90 return -1;
91 }
92
93 boot_params.apm_bios_info.version = ax;
94 boot_params.apm_bios_info.flags = cx;
95 return 0;
96}
97
98#endif