1*9a4bc520SJung-uk Kim /****************************************************************************** 2*9a4bc520SJung-uk Kim * 3*9a4bc520SJung-uk Kim * Module Name: utcksum - Support generating table checksums 4*9a4bc520SJung-uk Kim * 5*9a4bc520SJung-uk Kim *****************************************************************************/ 6*9a4bc520SJung-uk Kim 7*9a4bc520SJung-uk Kim /****************************************************************************** 8*9a4bc520SJung-uk Kim * 9*9a4bc520SJung-uk Kim * 1. Copyright Notice 10*9a4bc520SJung-uk Kim * 11*9a4bc520SJung-uk Kim * Some or all of this work - Copyright (c) 1999 - 2022, Intel Corp. 12*9a4bc520SJung-uk Kim * All rights reserved. 13*9a4bc520SJung-uk Kim * 14*9a4bc520SJung-uk Kim * 2. License 15*9a4bc520SJung-uk Kim * 16*9a4bc520SJung-uk Kim * 2.1. This is your license from Intel Corp. under its intellectual property 17*9a4bc520SJung-uk Kim * rights. You may have additional license terms from the party that provided 18*9a4bc520SJung-uk Kim * you this software, covering your right to use that party's intellectual 19*9a4bc520SJung-uk Kim * property rights. 20*9a4bc520SJung-uk Kim * 21*9a4bc520SJung-uk Kim * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a 22*9a4bc520SJung-uk Kim * copy of the source code appearing in this file ("Covered Code") an 23*9a4bc520SJung-uk Kim * irrevocable, perpetual, worldwide license under Intel's copyrights in the 24*9a4bc520SJung-uk Kim * base code distributed originally by Intel ("Original Intel Code") to copy, 25*9a4bc520SJung-uk Kim * make derivatives, distribute, use and display any portion of the Covered 26*9a4bc520SJung-uk Kim * Code in any form, with the right to sublicense such rights; and 27*9a4bc520SJung-uk Kim * 28*9a4bc520SJung-uk Kim * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent 29*9a4bc520SJung-uk Kim * license (with the right to sublicense), under only those claims of Intel 30*9a4bc520SJung-uk Kim * patents that are infringed by the Original Intel Code, to make, use, sell, 31*9a4bc520SJung-uk Kim * offer to sell, and import the Covered Code and derivative works thereof 32*9a4bc520SJung-uk Kim * solely to the minimum extent necessary to exercise the above copyright 33*9a4bc520SJung-uk Kim * license, and in no event shall the patent license extend to any additions 34*9a4bc520SJung-uk Kim * to or modifications of the Original Intel Code. No other license or right 35*9a4bc520SJung-uk Kim * is granted directly or by implication, estoppel or otherwise; 36*9a4bc520SJung-uk Kim * 37*9a4bc520SJung-uk Kim * The above copyright and patent license is granted only if the following 38*9a4bc520SJung-uk Kim * conditions are met: 39*9a4bc520SJung-uk Kim * 40*9a4bc520SJung-uk Kim * 3. Conditions 41*9a4bc520SJung-uk Kim * 42*9a4bc520SJung-uk Kim * 3.1. Redistribution of Source with Rights to Further Distribute Source. 43*9a4bc520SJung-uk Kim * Redistribution of source code of any substantial portion of the Covered 44*9a4bc520SJung-uk Kim * Code or modification with rights to further distribute source must include 45*9a4bc520SJung-uk Kim * the above Copyright Notice, the above License, this list of Conditions, 46*9a4bc520SJung-uk Kim * and the following Disclaimer and Export Compliance provision. In addition, 47*9a4bc520SJung-uk Kim * Licensee must cause all Covered Code to which Licensee contributes to 48*9a4bc520SJung-uk Kim * contain a file documenting the changes Licensee made to create that Covered 49*9a4bc520SJung-uk Kim * Code and the date of any change. Licensee must include in that file the 50*9a4bc520SJung-uk Kim * documentation of any changes made by any predecessor Licensee. Licensee 51*9a4bc520SJung-uk Kim * must include a prominent statement that the modification is derived, 52*9a4bc520SJung-uk Kim * directly or indirectly, from Original Intel Code. 53*9a4bc520SJung-uk Kim * 54*9a4bc520SJung-uk Kim * 3.2. Redistribution of Source with no Rights to Further Distribute Source. 55*9a4bc520SJung-uk Kim * Redistribution of source code of any substantial portion of the Covered 56*9a4bc520SJung-uk Kim * Code or modification without rights to further distribute source must 57*9a4bc520SJung-uk Kim * include the following Disclaimer and Export Compliance provision in the 58*9a4bc520SJung-uk Kim * documentation and/or other materials provided with distribution. In 59*9a4bc520SJung-uk Kim * addition, Licensee may not authorize further sublicense of source of any 60*9a4bc520SJung-uk Kim * portion of the Covered Code, and must include terms to the effect that the 61*9a4bc520SJung-uk Kim * license from Licensee to its licensee is limited to the intellectual 62*9a4bc520SJung-uk Kim * property embodied in the software Licensee provides to its licensee, and 63*9a4bc520SJung-uk Kim * not to intellectual property embodied in modifications its licensee may 64*9a4bc520SJung-uk Kim * make. 65*9a4bc520SJung-uk Kim * 66*9a4bc520SJung-uk Kim * 3.3. Redistribution of Executable. Redistribution in executable form of any 67*9a4bc520SJung-uk Kim * substantial portion of the Covered Code or modification must reproduce the 68*9a4bc520SJung-uk Kim * above Copyright Notice, and the following Disclaimer and Export Compliance 69*9a4bc520SJung-uk Kim * provision in the documentation and/or other materials provided with the 70*9a4bc520SJung-uk Kim * distribution. 71*9a4bc520SJung-uk Kim * 72*9a4bc520SJung-uk Kim * 3.4. Intel retains all right, title, and interest in and to the Original 73*9a4bc520SJung-uk Kim * Intel Code. 74*9a4bc520SJung-uk Kim * 75*9a4bc520SJung-uk Kim * 3.5. Neither the name Intel nor any other trademark owned or controlled by 76*9a4bc520SJung-uk Kim * Intel shall be used in advertising or otherwise to promote the sale, use or 77*9a4bc520SJung-uk Kim * other dealings in products derived from or relating to the Covered Code 78*9a4bc520SJung-uk Kim * without prior written authorization from Intel. 79*9a4bc520SJung-uk Kim * 80*9a4bc520SJung-uk Kim * 4. Disclaimer and Export Compliance 81*9a4bc520SJung-uk Kim * 82*9a4bc520SJung-uk Kim * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED 83*9a4bc520SJung-uk Kim * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE 84*9a4bc520SJung-uk Kim * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE, 85*9a4bc520SJung-uk Kim * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY 86*9a4bc520SJung-uk Kim * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY 87*9a4bc520SJung-uk Kim * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A 88*9a4bc520SJung-uk Kim * PARTICULAR PURPOSE. 89*9a4bc520SJung-uk Kim * 90*9a4bc520SJung-uk Kim * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES 91*9a4bc520SJung-uk Kim * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR 92*9a4bc520SJung-uk Kim * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT, 93*9a4bc520SJung-uk Kim * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY 94*9a4bc520SJung-uk Kim * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL 95*9a4bc520SJung-uk Kim * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS 96*9a4bc520SJung-uk Kim * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY 97*9a4bc520SJung-uk Kim * LIMITED REMEDY. 98*9a4bc520SJung-uk Kim * 99*9a4bc520SJung-uk Kim * 4.3. Licensee shall not export, either directly or indirectly, any of this 100*9a4bc520SJung-uk Kim * software or system incorporating such software without first obtaining any 101*9a4bc520SJung-uk Kim * required license or other approval from the U. S. Department of Commerce or 102*9a4bc520SJung-uk Kim * any other agency or department of the United States Government. In the 103*9a4bc520SJung-uk Kim * event Licensee exports any such software from the United States or 104*9a4bc520SJung-uk Kim * re-exports any such software from a foreign destination, Licensee shall 105*9a4bc520SJung-uk Kim * ensure that the distribution and export/re-export of the software is in 106*9a4bc520SJung-uk Kim * compliance with all laws, regulations, orders, or other restrictions of the 107*9a4bc520SJung-uk Kim * U.S. Export Administration Regulations. Licensee agrees that neither it nor 108*9a4bc520SJung-uk Kim * any of its subsidiaries will export/re-export any technical data, process, 109*9a4bc520SJung-uk Kim * software, or service, directly or indirectly, to any country for which the 110*9a4bc520SJung-uk Kim * United States government or any agency thereof requires an export license, 111*9a4bc520SJung-uk Kim * other governmental approval, or letter of assurance, without first obtaining 112*9a4bc520SJung-uk Kim * such license, approval or letter. 113*9a4bc520SJung-uk Kim * 114*9a4bc520SJung-uk Kim ***************************************************************************** 115*9a4bc520SJung-uk Kim * 116*9a4bc520SJung-uk Kim * Alternatively, you may choose to be licensed under the terms of the 117*9a4bc520SJung-uk Kim * following license: 118*9a4bc520SJung-uk Kim * 119*9a4bc520SJung-uk Kim * Redistribution and use in source and binary forms, with or without 120*9a4bc520SJung-uk Kim * modification, are permitted provided that the following conditions 121*9a4bc520SJung-uk Kim * are met: 122*9a4bc520SJung-uk Kim * 1. Redistributions of source code must retain the above copyright 123*9a4bc520SJung-uk Kim * notice, this list of conditions, and the following disclaimer, 124*9a4bc520SJung-uk Kim * without modification. 125*9a4bc520SJung-uk Kim * 2. Redistributions in binary form must reproduce at minimum a disclaimer 126*9a4bc520SJung-uk Kim * substantially similar to the "NO WARRANTY" disclaimer below 127*9a4bc520SJung-uk Kim * ("Disclaimer") and any redistribution must be conditioned upon 128*9a4bc520SJung-uk Kim * including a substantially similar Disclaimer requirement for further 129*9a4bc520SJung-uk Kim * binary redistribution. 130*9a4bc520SJung-uk Kim * 3. Neither the names of the above-listed copyright holders nor the names 131*9a4bc520SJung-uk Kim * of any contributors may be used to endorse or promote products derived 132*9a4bc520SJung-uk Kim * from this software without specific prior written permission. 133*9a4bc520SJung-uk Kim * 134*9a4bc520SJung-uk Kim * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 135*9a4bc520SJung-uk Kim * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 136*9a4bc520SJung-uk Kim * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 137*9a4bc520SJung-uk Kim * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 138*9a4bc520SJung-uk Kim * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 139*9a4bc520SJung-uk Kim * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 140*9a4bc520SJung-uk Kim * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 141*9a4bc520SJung-uk Kim * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 142*9a4bc520SJung-uk Kim * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 143*9a4bc520SJung-uk Kim * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 144*9a4bc520SJung-uk Kim * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 145*9a4bc520SJung-uk Kim * 146*9a4bc520SJung-uk Kim * Alternatively, you may choose to be licensed under the terms of the 147*9a4bc520SJung-uk Kim * GNU General Public License ("GPL") version 2 as published by the Free 148*9a4bc520SJung-uk Kim * Software Foundation. 149*9a4bc520SJung-uk Kim * 150*9a4bc520SJung-uk Kim *****************************************************************************/ 151*9a4bc520SJung-uk Kim 152*9a4bc520SJung-uk Kim #include <contrib/dev/acpica/include/acpi.h> 153*9a4bc520SJung-uk Kim #include <contrib/dev/acpica/include/accommon.h> 154*9a4bc520SJung-uk Kim #include <contrib/dev/acpica/include/acdisasm.h> 155*9a4bc520SJung-uk Kim #include <contrib/dev/acpica/include/acutils.h> 156*9a4bc520SJung-uk Kim 157*9a4bc520SJung-uk Kim 158*9a4bc520SJung-uk Kim /* This module used for application-level code only */ 159*9a4bc520SJung-uk Kim 160*9a4bc520SJung-uk Kim #define _COMPONENT ACPI_CA_DISASSEMBLER 161*9a4bc520SJung-uk Kim ACPI_MODULE_NAME ("utcksum") 162*9a4bc520SJung-uk Kim 163*9a4bc520SJung-uk Kim 164*9a4bc520SJung-uk Kim /******************************************************************************* 165*9a4bc520SJung-uk Kim * 166*9a4bc520SJung-uk Kim * FUNCTION: AcpiUtVerifyChecksum 167*9a4bc520SJung-uk Kim * 168*9a4bc520SJung-uk Kim * PARAMETERS: Table - ACPI table to verify 169*9a4bc520SJung-uk Kim * Length - Length of entire table 170*9a4bc520SJung-uk Kim * 171*9a4bc520SJung-uk Kim * RETURN: Status 172*9a4bc520SJung-uk Kim * 173*9a4bc520SJung-uk Kim * DESCRIPTION: Verifies that the table checksums to zero. Optionally returns 174*9a4bc520SJung-uk Kim * exception on bad checksum. 175*9a4bc520SJung-uk Kim * Note: We don't have to check for a CDAT here, since CDAT is 176*9a4bc520SJung-uk Kim * not in the RSDT/XSDT, and the CDAT table is never installed 177*9a4bc520SJung-uk Kim * via ACPICA. 178*9a4bc520SJung-uk Kim * 179*9a4bc520SJung-uk Kim ******************************************************************************/ 180*9a4bc520SJung-uk Kim 181*9a4bc520SJung-uk Kim ACPI_STATUS 182*9a4bc520SJung-uk Kim AcpiUtVerifyChecksum ( 183*9a4bc520SJung-uk Kim ACPI_TABLE_HEADER *Table, 184*9a4bc520SJung-uk Kim UINT32 Length) 185*9a4bc520SJung-uk Kim { 186*9a4bc520SJung-uk Kim UINT8 Checksum; 187*9a4bc520SJung-uk Kim 188*9a4bc520SJung-uk Kim 189*9a4bc520SJung-uk Kim /* 190*9a4bc520SJung-uk Kim * FACS/S3PT: 191*9a4bc520SJung-uk Kim * They are the odd tables, have no standard ACPI header and no checksum 192*9a4bc520SJung-uk Kim */ 193*9a4bc520SJung-uk Kim if (ACPI_COMPARE_NAMESEG (Table->Signature, ACPI_SIG_S3PT) || 194*9a4bc520SJung-uk Kim ACPI_COMPARE_NAMESEG (Table->Signature, ACPI_SIG_FACS)) 195*9a4bc520SJung-uk Kim { 196*9a4bc520SJung-uk Kim return (AE_OK); 197*9a4bc520SJung-uk Kim } 198*9a4bc520SJung-uk Kim 199*9a4bc520SJung-uk Kim /* Compute the checksum on the table */ 200*9a4bc520SJung-uk Kim 201*9a4bc520SJung-uk Kim Length = Table->Length; 202*9a4bc520SJung-uk Kim Checksum = AcpiUtGenerateChecksum (ACPI_CAST_PTR (UINT8, Table), Length, Table->Checksum); 203*9a4bc520SJung-uk Kim 204*9a4bc520SJung-uk Kim /* Computed checksum matches table? */ 205*9a4bc520SJung-uk Kim 206*9a4bc520SJung-uk Kim if (Checksum != Table->Checksum) 207*9a4bc520SJung-uk Kim { 208*9a4bc520SJung-uk Kim ACPI_BIOS_WARNING ((AE_INFO, 209*9a4bc520SJung-uk Kim "Incorrect checksum in table [%4.4s] - 0x%2.2X, " 210*9a4bc520SJung-uk Kim "should be 0x%2.2X", 211*9a4bc520SJung-uk Kim Table->Signature, Table->Checksum, 212*9a4bc520SJung-uk Kim Table->Checksum - Checksum)); 213*9a4bc520SJung-uk Kim 214*9a4bc520SJung-uk Kim #if (ACPI_CHECKSUM_ABORT) 215*9a4bc520SJung-uk Kim return (AE_BAD_CHECKSUM); 216*9a4bc520SJung-uk Kim #endif 217*9a4bc520SJung-uk Kim } 218*9a4bc520SJung-uk Kim 219*9a4bc520SJung-uk Kim return (AE_OK); 220*9a4bc520SJung-uk Kim } 221*9a4bc520SJung-uk Kim 222*9a4bc520SJung-uk Kim 223*9a4bc520SJung-uk Kim /******************************************************************************* 224*9a4bc520SJung-uk Kim * 225*9a4bc520SJung-uk Kim * FUNCTION: AcpiUtVerifyCdatChecksum 226*9a4bc520SJung-uk Kim * 227*9a4bc520SJung-uk Kim * PARAMETERS: Table - CDAT ACPI table to verify 228*9a4bc520SJung-uk Kim * Length - Length of entire table 229*9a4bc520SJung-uk Kim * 230*9a4bc520SJung-uk Kim * RETURN: Status 231*9a4bc520SJung-uk Kim * 232*9a4bc520SJung-uk Kim * DESCRIPTION: Verifies that the CDAT table checksums to zero. Optionally 233*9a4bc520SJung-uk Kim * returns an exception on bad checksum. 234*9a4bc520SJung-uk Kim * 235*9a4bc520SJung-uk Kim ******************************************************************************/ 236*9a4bc520SJung-uk Kim 237*9a4bc520SJung-uk Kim ACPI_STATUS 238*9a4bc520SJung-uk Kim AcpiUtVerifyCdatChecksum ( 239*9a4bc520SJung-uk Kim ACPI_TABLE_CDAT *CdatTable, 240*9a4bc520SJung-uk Kim UINT32 Length) 241*9a4bc520SJung-uk Kim { 242*9a4bc520SJung-uk Kim UINT8 Checksum; 243*9a4bc520SJung-uk Kim 244*9a4bc520SJung-uk Kim 245*9a4bc520SJung-uk Kim /* Compute the checksum on the table */ 246*9a4bc520SJung-uk Kim 247*9a4bc520SJung-uk Kim Checksum = AcpiUtGenerateChecksum (ACPI_CAST_PTR (UINT8, CdatTable), 248*9a4bc520SJung-uk Kim CdatTable->Length, CdatTable->Checksum); 249*9a4bc520SJung-uk Kim 250*9a4bc520SJung-uk Kim /* Computed checksum matches table? */ 251*9a4bc520SJung-uk Kim 252*9a4bc520SJung-uk Kim if (Checksum != CdatTable->Checksum) 253*9a4bc520SJung-uk Kim { 254*9a4bc520SJung-uk Kim ACPI_BIOS_WARNING ((AE_INFO, 255*9a4bc520SJung-uk Kim "Incorrect checksum in table [%4.4s] - 0x%2.2X, " 256*9a4bc520SJung-uk Kim "should be 0x%2.2X", 257*9a4bc520SJung-uk Kim AcpiGbl_CDAT, CdatTable->Checksum, Checksum)); 258*9a4bc520SJung-uk Kim 259*9a4bc520SJung-uk Kim #if (ACPI_CHECKSUM_ABORT) 260*9a4bc520SJung-uk Kim return (AE_BAD_CHECKSUM); 261*9a4bc520SJung-uk Kim #endif 262*9a4bc520SJung-uk Kim } 263*9a4bc520SJung-uk Kim 264*9a4bc520SJung-uk Kim CdatTable->Checksum = Checksum; 265*9a4bc520SJung-uk Kim return (AE_OK); 266*9a4bc520SJung-uk Kim } 267*9a4bc520SJung-uk Kim 268*9a4bc520SJung-uk Kim 269*9a4bc520SJung-uk Kim /******************************************************************************* 270*9a4bc520SJung-uk Kim * 271*9a4bc520SJung-uk Kim * FUNCTION: AcpiUtGenerateChecksum 272*9a4bc520SJung-uk Kim * 273*9a4bc520SJung-uk Kim * PARAMETERS: Table - Pointer to table to be checksummed 274*9a4bc520SJung-uk Kim * Length - Length of the table 275*9a4bc520SJung-uk Kim * OriginalChecksum - Value of the checksum field 276*9a4bc520SJung-uk Kim * 277*9a4bc520SJung-uk Kim * RETURN: 8 bit checksum of buffer 278*9a4bc520SJung-uk Kim * 279*9a4bc520SJung-uk Kim * DESCRIPTION: Computes an 8 bit checksum of the table. 280*9a4bc520SJung-uk Kim * 281*9a4bc520SJung-uk Kim ******************************************************************************/ 282*9a4bc520SJung-uk Kim 283*9a4bc520SJung-uk Kim UINT8 284*9a4bc520SJung-uk Kim AcpiUtGenerateChecksum ( 285*9a4bc520SJung-uk Kim void *Table, 286*9a4bc520SJung-uk Kim UINT32 Length, 287*9a4bc520SJung-uk Kim UINT8 OriginalChecksum) 288*9a4bc520SJung-uk Kim { 289*9a4bc520SJung-uk Kim UINT8 Checksum; 290*9a4bc520SJung-uk Kim 291*9a4bc520SJung-uk Kim 292*9a4bc520SJung-uk Kim /* Sum the entire table as-is */ 293*9a4bc520SJung-uk Kim 294*9a4bc520SJung-uk Kim Checksum = AcpiUtChecksum ((UINT8 *) Table, Length); 295*9a4bc520SJung-uk Kim 296*9a4bc520SJung-uk Kim /* Subtract off the existing checksum value in the table */ 297*9a4bc520SJung-uk Kim 298*9a4bc520SJung-uk Kim Checksum = (UINT8) (Checksum - OriginalChecksum); 299*9a4bc520SJung-uk Kim 300*9a4bc520SJung-uk Kim /* Compute and return the final checksum */ 301*9a4bc520SJung-uk Kim 302*9a4bc520SJung-uk Kim Checksum = (UINT8) (0 - Checksum); 303*9a4bc520SJung-uk Kim return (Checksum); 304*9a4bc520SJung-uk Kim } 305*9a4bc520SJung-uk Kim 306*9a4bc520SJung-uk Kim 307*9a4bc520SJung-uk Kim /******************************************************************************* 308*9a4bc520SJung-uk Kim * 309*9a4bc520SJung-uk Kim * FUNCTION: AcpiUtChecksum 310*9a4bc520SJung-uk Kim * 311*9a4bc520SJung-uk Kim * PARAMETERS: Buffer - Pointer to memory region to be checked 312*9a4bc520SJung-uk Kim * Length - Length of this memory region 313*9a4bc520SJung-uk Kim * 314*9a4bc520SJung-uk Kim * RETURN: Checksum (UINT8) 315*9a4bc520SJung-uk Kim * 316*9a4bc520SJung-uk Kim * DESCRIPTION: Calculates circular checksum of memory region. 317*9a4bc520SJung-uk Kim * 318*9a4bc520SJung-uk Kim ******************************************************************************/ 319*9a4bc520SJung-uk Kim 320*9a4bc520SJung-uk Kim UINT8 321*9a4bc520SJung-uk Kim AcpiUtChecksum ( 322*9a4bc520SJung-uk Kim UINT8 *Buffer, 323*9a4bc520SJung-uk Kim UINT32 Length) 324*9a4bc520SJung-uk Kim { 325*9a4bc520SJung-uk Kim UINT8 Sum = 0; 326*9a4bc520SJung-uk Kim UINT8 *End = Buffer + Length; 327*9a4bc520SJung-uk Kim 328*9a4bc520SJung-uk Kim 329*9a4bc520SJung-uk Kim while (Buffer < End) 330*9a4bc520SJung-uk Kim { 331*9a4bc520SJung-uk Kim Sum = (UINT8) (Sum + *(Buffer++)); 332*9a4bc520SJung-uk Kim } 333*9a4bc520SJung-uk Kim 334*9a4bc520SJung-uk Kim return (Sum); 335*9a4bc520SJung-uk Kim } 336