src/core/acpi.c

   1 /*
   2  * Copyright (C) 2006 Michael Brown <mbrown@fensystems.co.uk>.
   3  *
   4  * This program is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU General Public License as
   6  * published by the Free Software Foundation; either version 2 of the
   7  * License, or any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  17  */
  18
  19 FILE_LICENCE ( GPL2_OR_LATER );
  20
  21 #include <gpxe/acpi.h>
  22
  23 /** @file
  24  *
  25  * ACPI support functions
  26  *
  27  */
  28
  29 /**
  30  * Fix up ACPI table checksum
  31  *
  32  * @v acpi              ACPI table header
  33  */
  34 void acpi_fix_checksum ( struct acpi_description_header *acpi ) {
  35         unsigned int i = 0;
  36         uint8_t sum = 0;
  37
  38         for ( i = 0 ; i < acpi->length ; i++ ) {
  39                 sum += *( ( ( uint8_t * ) acpi ) + i );
  40         }
  41         acpi->checksum -= sum;
  42 }