LXR linux/arch/x86/include/asm/apm.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2/*
   3 *  Machine specific APM BIOS functions for generic.
   4 *  Split out from apm.c by Osamu Tomita <tomita@cinet.co.jp>
   5 */
   6
   7#ifndef _ASM_X86_MACH_DEFAULT_APM_H
   8#define _ASM_X86_MACH_DEFAULT_APM_H
   9
  10#ifdef APM_ZERO_SEGS
  11#       define APM_DO_ZERO_SEGS \
  12                "pushl %%ds\n\t" \
  13                "pushl %%es\n\t" \
  14                "xorl %%edx, %%edx\n\t" \
  15                "mov %%dx, %%ds\n\t" \
  16                "mov %%dx, %%es\n\t" \
  17                "mov %%dx, %%fs\n\t" \
  18                "mov %%dx, %%gs\n\t"
  19#       define APM_DO_POP_SEGS \
  20                "popl %%es\n\t" \
  21                "popl %%ds\n\t"
  22#else
  23#       define APM_DO_ZERO_SEGS
  24#       define APM_DO_POP_SEGS
  25#endif
  26
  27static inline void apm_bios_call_asm(u32 func, u32 ebx_in, u32 ecx_in,
  28                                        u32 *eax, u32 *ebx, u32 *ecx,
  29                                        u32 *edx, u32 *esi)
  30{
  31        /*
  32         * N.B. We do NOT need a cld after the BIOS call
  33         * because we always save and restore the flags.
  34         */
  35        __asm__ __volatile__(APM_DO_ZERO_SEGS
  36                "pushl %%edi\n\t"
  37                "pushl %%ebp\n\t"
  38                "lcall *%%cs:apm_bios_entry\n\t"
  39                "setc %%al\n\t"
  40                "popl %%ebp\n\t"
  41                "popl %%edi\n\t"
  42                APM_DO_POP_SEGS
  43                : "=a" (*eax), "=b" (*ebx), "=c" (*ecx), "=d" (*edx),
  44                  "=S" (*esi)
  45                : "a" (func), "b" (ebx_in), "c" (ecx_in)
  46                : "memory", "cc");
  47}
  48
  49static inline bool apm_bios_call_simple_asm(u32 func, u32 ebx_in,
  50                                            u32 ecx_in, u32 *eax)
  51{
  52        int     cx, dx, si;
  53        bool    error;
  54
  55        /*
  56         * N.B. We do NOT need a cld after the BIOS call
  57         * because we always save and restore the flags.
  58         */
  59        __asm__ __volatile__(APM_DO_ZERO_SEGS
  60                "pushl %%edi\n\t"
  61                "pushl %%ebp\n\t"
  62                "lcall *%%cs:apm_bios_entry\n\t"
  63                "setc %%bl\n\t"
  64                "popl %%ebp\n\t"
  65                "popl %%edi\n\t"
  66                APM_DO_POP_SEGS
  67                : "=a" (*eax), "=b" (error), "=c" (cx), "=d" (dx),
  68                  "=S" (si)
  69                : "a" (func), "b" (ebx_in), "c" (ecx_in)
  70                : "memory", "cc");
  71        return error;
  72}
  73
  74#endif /* _ASM_X86_MACH_DEFAULT_APM_H */
  75