apm.h

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/*
 *  Machine specific APM BIOS functions for generic.
 *  Split out from apm.c by Osamu Tomita <[email protected]>
 */

#ifndef _ASM_X86_MACH_DEFAULT_APM_H
#define _ASM_X86_MACH_DEFAULT_APM_H

#ifdef APM_ZERO_SEGS
#   define APM_DO_ZERO_SEGS \
        "pushl %%ds\n\t" \
        "pushl %%es\n\t" \
        "xorl %%edx, %%edx\n\t" \
        "mov %%dx, %%ds\n\t" \
        "mov %%dx, %%es\n\t" \
        "mov %%dx, %%fs\n\t" \
        "mov %%dx, %%gs\n\t"
#   define APM_DO_POP_SEGS \
        "popl %%es\n\t" \
        "popl %%ds\n\t"
#else
#   define APM_DO_ZERO_SEGS
#   define APM_DO_POP_SEGS
#endif

static inline void apm_bios_call_asm(u32 func, u32 ebx_in, u32 ecx_in,
                    u32 *eax, u32 *ebx, u32 *ecx,
                    u32 *edx, u32 *esi)
{
    /*
     * N.B. We do NOT need a cld after the BIOS call
     * because we always save and restore the flags.
     */
    __asm__ __volatile__(APM_DO_ZERO_SEGS
        "pushl %%edi\n\t"
        "pushl %%ebp\n\t"
        "lcall *%%cs:apm_bios_entry\n\t"
        "setc %%al\n\t"
        "popl %%ebp\n\t"
        "popl %%edi\n\t"
        APM_DO_POP_SEGS
        : "=a" (*eax), "=b" (*ebx), "=c" (*ecx), "=d" (*edx),
          "=S" (*esi)
        : "a" (func), "b" (ebx_in), "c" (ecx_in)
        : "memory", "cc");
}

static inline u8 apm_bios_call_simple_asm(u32 func, u32 ebx_in,
                        u32 ecx_in, u32 *eax)
{
    int cx, dx, si;
    u8  error;

    /*
     * N.B. We do NOT need a cld after the BIOS call
     * because we always save and restore the flags.
     */
    __asm__ __volatile__(APM_DO_ZERO_SEGS
        "pushl %%edi\n\t"
        "pushl %%ebp\n\t"
        "lcall *%%cs:apm_bios_entry\n\t"
        "setc %%bl\n\t"
        "popl %%ebp\n\t"
        "popl %%edi\n\t"
        APM_DO_POP_SEGS
        : "=a" (*eax), "=b" (error), "=c" (cx), "=d" (dx),
          "=S" (si)
        : "a" (func), "b" (ebx_in), "c" (ecx_in)
        : "memory", "cc");
    return error;
}

#endif /* _ASM_X86_MACH_DEFAULT_APM_H */