xref: /openbmc/linux/arch/x86/include/asm/apm.h (revision bc5aa3a0)
1 /*
2  *  Machine specific APM BIOS functions for generic.
3  *  Split out from apm.c by Osamu Tomita <tomita@cinet.co.jp>
4  */
5 
6 #ifndef _ASM_X86_MACH_DEFAULT_APM_H
7 #define _ASM_X86_MACH_DEFAULT_APM_H
8 
9 #ifdef APM_ZERO_SEGS
10 #	define APM_DO_ZERO_SEGS \
11 		"pushl %%ds\n\t" \
12 		"pushl %%es\n\t" \
13 		"xorl %%edx, %%edx\n\t" \
14 		"mov %%dx, %%ds\n\t" \
15 		"mov %%dx, %%es\n\t" \
16 		"mov %%dx, %%fs\n\t" \
17 		"mov %%dx, %%gs\n\t"
18 #	define APM_DO_POP_SEGS \
19 		"popl %%es\n\t" \
20 		"popl %%ds\n\t"
21 #else
22 #	define APM_DO_ZERO_SEGS
23 #	define APM_DO_POP_SEGS
24 #endif
25 
26 static inline void apm_bios_call_asm(u32 func, u32 ebx_in, u32 ecx_in,
27 					u32 *eax, u32 *ebx, u32 *ecx,
28 					u32 *edx, u32 *esi)
29 {
30 	/*
31 	 * N.B. We do NOT need a cld after the BIOS call
32 	 * because we always save and restore the flags.
33 	 */
34 	__asm__ __volatile__(APM_DO_ZERO_SEGS
35 		"pushl %%edi\n\t"
36 		"pushl %%ebp\n\t"
37 		"lcall *%%cs:apm_bios_entry\n\t"
38 		"setc %%al\n\t"
39 		"popl %%ebp\n\t"
40 		"popl %%edi\n\t"
41 		APM_DO_POP_SEGS
42 		: "=a" (*eax), "=b" (*ebx), "=c" (*ecx), "=d" (*edx),
43 		  "=S" (*esi)
44 		: "a" (func), "b" (ebx_in), "c" (ecx_in)
45 		: "memory", "cc");
46 }
47 
48 static inline bool apm_bios_call_simple_asm(u32 func, u32 ebx_in,
49 					    u32 ecx_in, u32 *eax)
50 {
51 	int	cx, dx, si;
52 	bool	error;
53 
54 	/*
55 	 * N.B. We do NOT need a cld after the BIOS call
56 	 * because we always save and restore the flags.
57 	 */
58 	__asm__ __volatile__(APM_DO_ZERO_SEGS
59 		"pushl %%edi\n\t"
60 		"pushl %%ebp\n\t"
61 		"lcall *%%cs:apm_bios_entry\n\t"
62 		"setc %%bl\n\t"
63 		"popl %%ebp\n\t"
64 		"popl %%edi\n\t"
65 		APM_DO_POP_SEGS
66 		: "=a" (*eax), "=b" (error), "=c" (cx), "=d" (dx),
67 		  "=S" (si)
68 		: "a" (func), "b" (ebx_in), "c" (ecx_in)
69 		: "memory", "cc");
70 	return error;
71 }
72 
73 #endif /* _ASM_X86_MACH_DEFAULT_APM_H */
74