39 lines
		
	
	
		
			927 B
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			39 lines
		
	
	
		
			927 B
		
	
	
	
		
			C
		
	
	
	
	
	
/* -*- linux-c -*- ------------------------------------------------------- *
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 *
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 *   Copyright (C) 1991, 1992 Linus Torvalds
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 *   Copyright 2007 rPath, Inc. - All Rights Reserved
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 *   Copyright 2009 Intel Corporation; author H. Peter Anvin
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 *
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 *   This file is part of the Linux kernel, and is made available under
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 *   the terms of the GNU General Public License version 2.
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 *
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 * ----------------------------------------------------------------------- */
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/*
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 * Get the MCA system description table
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 */
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#include "boot.h"
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int query_mca(void)
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{
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	struct biosregs ireg, oreg;
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	u16 len;
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	initregs(&ireg);
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	ireg.ah = 0xc0;
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	intcall(0x15, &ireg, &oreg);
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	if (oreg.eflags & X86_EFLAGS_CF)
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		return -1;	/* No MCA present */
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	set_fs(oreg.es);
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	len = rdfs16(oreg.bx);
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	if (len > sizeof(boot_params.sys_desc_table))
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		len = sizeof(boot_params.sys_desc_table);
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	copy_from_fs(&boot_params.sys_desc_table, oreg.bx, len);
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	return 0;
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}
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