/*      $NetBSD: biosmemps2.S,v 1.7 2016/12/04 08:21:08 maxv Exp $      */

/*
 * Copyright (c) 2003 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by Jaromir Dolecek.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#include <machine/asm.h>

        .text

/*
 * int getextmemps2(void *buffer)
 *
 * call int 15 function 0xc7 - later PS/2s - RETURN MEMORY-MAP INFORMATION
 * return: 0=OK, nonzero=error
 * buffer: filled with memory-map table structure
 */
ENTRY(getextmemps2)
        .code32
        movl    %eax,%edx
        xorl    %eax,%eax
        pusha

        call    _C_LABEL(prot_to_real)
        .code16

        /* do int15, function 0xc0 call to discover if C7h is supported */
        movb    $0xc0,%ah
        int     $0x15
        setc    %cl
        jc      out             /* 0xc0 not supported if carry set */

        /* check feature byte 2, bit 4 to see if return memory map is supported */
        movb    %es:6(%bx),%al
        andb    $0x10,%al
        jnz     getmem          /* 0xc7 supported */

        /* set %cl to indicate failure, and exit */
        movb    $2,%cl
        jmp     out

getmem:
        /* move the parameter to right register */
        push    %ds
        movl    %edx,%esi
        andl    $0xf,%esi
        shrl    $4,%edx
        mov     %ds,%ax
        add     %dx,%ax
        mov     %ax,%ds

        /* actually call int15, function 0xc7 now */
        movb    $0xc7,%ah
        int     $0x15
        setc    %cl             /* save carry */
        pop     %ds

out:
        calll   _C_LABEL(real_to_prot)
        .code32

        movb    %cl,28(%esp)
        popa
        ret