text: /*
   * Copyright (C) 2014 Michael Brown <mbrown@fensystems.co.uk>.
   *
   * This program is free software; you can redistribute it and/or
   * modify it under the terms of the GNU General Public License as
   * published by the Free Software Foundation; either version 2 of the
   * License, or any later version.
   *
   * This program is distributed in the hope that it will be useful, but
   * WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   * General Public License for more details.
   *
   * You should have received a copy of the GNU General Public License
   * along with this program; if not, write to the Free Software
   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
   * 02110-1301, USA.
   */
  
  FILE_LICENCE ( GPL2_OR_LATER );
  
  /** @file
   *
   * Integer square root
   *
   */
  
  #include <ipxe/isqrt.h>
  
  /**
   * Find integer square root
   *
   * @v value		Value
   * @v isqrt		Integer square root of value
   */
  unsigned long isqrt ( unsigned long value ) {
  	unsigned long result = 0;
  	unsigned long bit = ( 1UL << ( ( 8 * sizeof ( bit ) ) - 2 ) );
  
  	while ( bit > value )
  		bit >>= 2;
  	while ( bit ) {
  		if ( value >= ( result + bit ) ) {
  			value -= ( result + bit );
  			result = ( ( result >> 1 ) + bit );
  		} else {
  			result >>= 1;
  		}
  		bit >>= 2;
  	}
  	return result;
  }
  