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      1 /*	$NetBSD: biosmemps2.S,v 1.7 2016/12/04 08:21:08 maxv Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 2003 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Jaromir Dolecek.
      9  *
     10  * Redistribution and use in source and binary forms, with or without
     11  * modification, are permitted provided that the following conditions
     12  * are met:
     13  * 1. Redistributions of source code must retain the above copyright
     14  *    notice, this list of conditions and the following disclaimer.
     15  * 2. Redistributions in binary form must reproduce the above copyright
     16  *    notice, this list of conditions and the following disclaimer in the
     17  *    documentation and/or other materials provided with the distribution.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     29  * POSSIBILITY OF SUCH DAMAGE.
     30  */
     31 
     32 #include <machine/asm.h>
     33 
     34 	.text
     35 
     36 /*
     37  * int getextmemps2(void *buffer)
     38  *
     39  * call int 15 function 0xc7 - later PS/2s - RETURN MEMORY-MAP INFORMATION
     40  * return: 0=OK, nonzero=error
     41  * buffer: filled with memory-map table structure
     42  */
     43 ENTRY(getextmemps2)
     44 	.code32
     45 	movl	%eax,%edx
     46 	xorl	%eax,%eax
     47 	pusha
     48 
     49 	call	_C_LABEL(prot_to_real)
     50 	.code16
     51 
     52 	/* do int15, function 0xc0 call to discover if C7h is supported */
     53 	movb	$0xc0,%ah
     54 	int	$0x15
     55 	setc	%cl
     56 	jc	out		/* 0xc0 not supported if carry set */
     57 
     58 	/* check feature byte 2, bit 4 to see if return memory map is supported */
     59 	movb	%es:6(%bx),%al
     60 	andb	$0x10,%al
     61 	jnz	getmem		/* 0xc7 supported */
     62 
     63 	/* set %cl to indicate failure, and exit */
     64 	movb	$2,%cl
     65 	jmp	out
     66 
     67 getmem:
     68 	/* move the parameter to right register */
     69 	push	%ds
     70 	movl	%edx,%esi
     71 	andl	$0xf,%esi
     72 	shrl	$4,%edx
     73 	mov	%ds,%ax
     74 	add	%dx,%ax
     75 	mov	%ax,%ds
     76 
     77 	/* actually call int15, function 0xc7 now */
     78 	movb	$0xc7,%ah
     79 	int	$0x15
     80 	setc	%cl		/* save carry */
     81 	pop	%ds
     82 
     83 out:
     84 	calll	_C_LABEL(real_to_prot)
     85 	.code32
     86 
     87 	movb	%cl,28(%esp)
     88 	popa
     89 	ret
     90 
     91