/******************************************************************************* * * Module Name: utmath - Integer math support routines * $Revision: 12 $ * ******************************************************************************/ /****************************************************************************** * * 1. Copyright Notice * * Some or all of this work - Copyright (c) 1999 - 2003, Intel Corp. * All rights reserved. * * 2. License * * 2.1. This is your license from Intel Corp. under its intellectual property * rights. You may have additional license terms from the party that provided * you this software, covering your right to use that party's intellectual * property rights. * * 2.2. Intel grants, free of charge, to any person ("Licensee") obtaining a * copy of the source code appearing in this file ("Covered Code") an * irrevocable, perpetual, worldwide license under Intel's copyrights in the * base code distributed originally by Intel ("Original Intel Code") to copy, * make derivatives, distribute, use and display any portion of the Covered * Code in any form, with the right to sublicense such rights; and * * 2.3. Intel grants Licensee a non-exclusive and non-transferable patent * license (with the right to sublicense), under only those claims of Intel * patents that are infringed by the Original Intel Code, to make, use, sell, * offer to sell, and import the Covered Code and derivative works thereof * solely to the minimum extent necessary to exercise the above copyright * license, and in no event shall the patent license extend to any additions * to or modifications of the Original Intel Code. No other license or right * is granted directly or by implication, estoppel or otherwise; * * The above copyright and patent license is granted only if the following * conditions are met: * * 3. Conditions * * 3.1. Redistribution of Source with Rights to Further Distribute Source. * Redistribution of source code of any substantial portion of the Covered * Code or modification with rights to further distribute source must include * the above Copyright Notice, the above License, this list of Conditions, * and the following Disclaimer and Export Compliance provision. In addition, * Licensee must cause all Covered Code to which Licensee contributes to * contain a file documenting the changes Licensee made to create that Covered * Code and the date of any change. Licensee must include in that file the * documentation of any changes made by any predecessor Licensee. Licensee * must include a prominent statement that the modification is derived, * directly or indirectly, from Original Intel Code. * * 3.2. Redistribution of Source with no Rights to Further Distribute Source. * Redistribution of source code of any substantial portion of the Covered * Code or modification without rights to further distribute source must * include the following Disclaimer and Export Compliance provision in the * documentation and/or other materials provided with distribution. In * addition, Licensee may not authorize further sublicense of source of any * portion of the Covered Code, and must include terms to the effect that the * license from Licensee to its licensee is limited to the intellectual * property embodied in the software Licensee provides to its licensee, and * not to intellectual property embodied in modifications its licensee may * make. * * 3.3. Redistribution of Executable. Redistribution in executable form of any * substantial portion of the Covered Code or modification must reproduce the * above Copyright Notice, and the following Disclaimer and Export Compliance * provision in the documentation and/or other materials provided with the * distribution. * * 3.4. Intel retains all right, title, and interest in and to the Original * Intel Code. * * 3.5. Neither the name Intel nor any other trademark owned or controlled by * Intel shall be used in advertising or otherwise to promote the sale, use or * other dealings in products derived from or relating to the Covered Code * without prior written authorization from Intel. * * 4. Disclaimer and Export Compliance * * 4.1. INTEL MAKES NO WARRANTY OF ANY KIND REGARDING ANY SOFTWARE PROVIDED * HERE. ANY SOFTWARE ORIGINATING FROM INTEL OR DERIVED FROM INTEL SOFTWARE * IS PROVIDED "AS IS," AND INTEL WILL NOT PROVIDE ANY SUPPORT, ASSISTANCE, * INSTALLATION, TRAINING OR OTHER SERVICES. INTEL WILL NOT PROVIDE ANY * UPDATES, ENHANCEMENTS OR EXTENSIONS. INTEL SPECIFICALLY DISCLAIMS ANY * IMPLIED WARRANTIES OF MERCHANTABILITY, NONINFRINGEMENT AND FITNESS FOR A * PARTICULAR PURPOSE. * * 4.2. IN NO EVENT SHALL INTEL HAVE ANY LIABILITY TO LICENSEE, ITS LICENSEES * OR ANY OTHER THIRD PARTY, FOR ANY LOST PROFITS, LOST DATA, LOSS OF USE OR * COSTS OF PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES, OR FOR ANY INDIRECT, * SPECIAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THIS AGREEMENT, UNDER ANY * CAUSE OF ACTION OR THEORY OF LIABILITY, AND IRRESPECTIVE OF WHETHER INTEL * HAS ADVANCE NOTICE OF THE POSSIBILITY OF SUCH DAMAGES. THESE LIMITATIONS * SHALL APPLY NOTWITHSTANDING THE FAILURE OF THE ESSENTIAL PURPOSE OF ANY * LIMITED REMEDY. * * 4.3. Licensee shall not export, either directly or indirectly, any of this * software or system incorporating such software without first obtaining any * required license or other approval from the U. S. Department of Commerce or * any other agency or department of the United States Government. In the * event Licensee exports any such software from the United States or * re-exports any such software from a foreign destination, Licensee shall * ensure that the distribution and export/re-export of the software is in * compliance with all laws, regulations, orders, or other restrictions of the * U.S. Export Administration Regulations. Licensee agrees that neither it nor * any of its subsidiaries will export/re-export any technical data, process, * software, or service, directly or indirectly, to any country for which the * United States government or any agency thereof requires an export license, * other governmental approval, or letter of assurance, without first obtaining * such license, approval or letter. * *****************************************************************************/ #define __UTMATH_C__ #include "acpi.h" #define _COMPONENT ACPI_UTILITIES ACPI_MODULE_NAME ("utmath") /* * Support for double-precision integer divide. This code is included here * in order to support kernel environments where the double-precision math * library is not available. */ #ifndef ACPI_USE_NATIVE_DIVIDE /******************************************************************************* * * FUNCTION: AcpiUtShortDivide * * PARAMETERS: InDividend - Pointer to the dividend * Divisor - 32-bit divisor * OutQuotient - Pointer to where the quotient is returned * OutRemainder - Pointer to where the remainder is returned * * RETURN: Status (Checks for divide-by-zero) * * DESCRIPTION: Perform a short (maximum 64 bits divided by 32 bits) * divide and modulo. The result is a 64-bit quotient and a * 32-bit remainder. * ******************************************************************************/ ACPI_STATUS AcpiUtShortDivide ( ACPI_INTEGER *InDividend, UINT32 Divisor, ACPI_INTEGER *OutQuotient, UINT32 *OutRemainder) { UINT64_OVERLAY Dividend; UINT64_OVERLAY Quotient; UINT32 Remainder32; ACPI_FUNCTION_TRACE ("UtShortDivide"); Dividend.Full = *InDividend; /* Always check for a zero divisor */ if (Divisor == 0) { ACPI_REPORT_ERROR (("AcpiUtShortDivide: Divide by zero\n")); return_ACPI_STATUS (AE_AML_DIVIDE_BY_ZERO); } /* * The quotient is 64 bits, the remainder is always 32 bits, * and is generated by the second divide. */ ACPI_DIV_64_BY_32 (0, Dividend.Part.Hi, Divisor, Quotient.Part.Hi, Remainder32); ACPI_DIV_64_BY_32 (Remainder32, Dividend.Part.Lo, Divisor, Quotient.Part.Lo, Remainder32); /* Return only what was requested */ if (OutQuotient) { *OutQuotient = Quotient.Full; } if (OutRemainder) { *OutRemainder = Remainder32; } return_ACPI_STATUS (AE_OK); } /******************************************************************************* * * FUNCTION: AcpiUtDivide * * PARAMETERS: InDividend - Pointer to the dividend * InDivisor - Pointer to the divisor * OutQuotient - Pointer to where the quotient is returned * OutRemainder - Pointer to where the remainder is returned * * RETURN: Status (Checks for divide-by-zero) * * DESCRIPTION: Perform a divide and modulo. * ******************************************************************************/ ACPI_STATUS AcpiUtDivide ( ACPI_INTEGER *InDividend, ACPI_INTEGER *InDivisor, ACPI_INTEGER *OutQuotient, ACPI_INTEGER *OutRemainder) { UINT64_OVERLAY Dividend; UINT64_OVERLAY Divisor; UINT64_OVERLAY Quotient; UINT64_OVERLAY Remainder; UINT64_OVERLAY NormalizedDividend; UINT64_OVERLAY NormalizedDivisor; UINT32 Partial1; UINT64_OVERLAY Partial2; UINT64_OVERLAY Partial3; ACPI_FUNCTION_TRACE ("UtDivide"); /* Always check for a zero divisor */ if (*InDivisor == 0) { ACPI_REPORT_ERROR (("AcpiUtDivide: Divide by zero\n")); return_ACPI_STATUS (AE_AML_DIVIDE_BY_ZERO); } Divisor.Full = *InDivisor; Dividend.Full = *InDividend; if (Divisor.Part.Hi == 0) { /* * 1) Simplest case is where the divisor is 32 bits, we can * just do two divides */ Remainder.Part.Hi = 0; /* * The quotient is 64 bits, the remainder is always 32 bits, * and is generated by the second divide. */ ACPI_DIV_64_BY_32 (0, Dividend.Part.Hi, Divisor.Part.Lo, Quotient.Part.Hi, Partial1); ACPI_DIV_64_BY_32 (Partial1, Dividend.Part.Lo, Divisor.Part.Lo, Quotient.Part.Lo, Remainder.Part.Lo); } else { /* * 2) The general case where the divisor is a full 64 bits * is more difficult */ Quotient.Part.Hi = 0; NormalizedDividend = Dividend; NormalizedDivisor = Divisor; /* Normalize the operands (shift until the divisor is < 32 bits) */ do { ACPI_SHIFT_RIGHT_64 (NormalizedDivisor.Part.Hi, NormalizedDivisor.Part.Lo); ACPI_SHIFT_RIGHT_64 (NormalizedDividend.Part.Hi, NormalizedDividend.Part.Lo); } while (NormalizedDivisor.Part.Hi != 0); /* Partial divide */ ACPI_DIV_64_BY_32 (NormalizedDividend.Part.Hi, NormalizedDividend.Part.Lo, NormalizedDivisor.Part.Lo, Quotient.Part.Lo, Partial1); /* * The quotient is always 32 bits, and simply requires adjustment. * The 64-bit remainder must be generated. */ Partial1 = Quotient.Part.Lo * Divisor.Part.Hi; Partial2.Full = (ACPI_INTEGER) Quotient.Part.Lo * Divisor.Part.Lo; Partial3.Full = (ACPI_INTEGER) Partial2.Part.Hi + Partial1; Remainder.Part.Hi = Partial3.Part.Lo; Remainder.Part.Lo = Partial2.Part.Lo; if (Partial3.Part.Hi == 0) { if (Partial3.Part.Lo >= Dividend.Part.Hi) { if (Partial3.Part.Lo == Dividend.Part.Hi) { if (Partial2.Part.Lo > Dividend.Part.Lo) { Quotient.Part.Lo--; Remainder.Full -= Divisor.Full; } } else { Quotient.Part.Lo--; Remainder.Full -= Divisor.Full; } } Remainder.Full = Remainder.Full - Dividend.Full; Remainder.Part.Hi = (UINT32) -((INT32) Remainder.Part.Hi); Remainder.Part.Lo = (UINT32) -((INT32) Remainder.Part.Lo); if (Remainder.Part.Lo) { Remainder.Part.Hi--; } } } /* Return only what was requested */ if (OutQuotient) { *OutQuotient = Quotient.Full; } if (OutRemainder) { *OutRemainder = Remainder.Full; } return_ACPI_STATUS (AE_OK); } #else /******************************************************************************* * * FUNCTION: AcpiUtShortDivide, AcpiUtDivide * * DESCRIPTION: Native versions of the UtDivide functions. Use these if either * 1) The target is a 64-bit platform and therefore 64-bit * integer math is supported directly by the machine. * 2) The target is a 32-bit or 16-bit platform, and the * double-precision integer math library is available to * perform the divide. * ******************************************************************************/ ACPI_STATUS AcpiUtShortDivide ( ACPI_INTEGER *InDividend, UINT32 Divisor, ACPI_INTEGER *OutQuotient, UINT32 *OutRemainder) { ACPI_FUNCTION_TRACE ("UtShortDivide"); /* Always check for a zero divisor */ if (Divisor == 0) { ACPI_REPORT_ERROR (("AcpiUtShortDivide: Divide by zero\n")); return_ACPI_STATUS (AE_AML_DIVIDE_BY_ZERO); } /* Return only what was requested */ if (OutQuotient) { *OutQuotient = *InDividend / Divisor; } if (OutRemainder) { *OutRemainder = (UINT32) *InDividend % Divisor; } return_ACPI_STATUS (AE_OK); } ACPI_STATUS AcpiUtDivide ( ACPI_INTEGER *InDividend, ACPI_INTEGER *InDivisor, ACPI_INTEGER *OutQuotient, ACPI_INTEGER *OutRemainder) { ACPI_FUNCTION_TRACE ("UtDivide"); /* Always check for a zero divisor */ if (*InDivisor == 0) { ACPI_REPORT_ERROR (("AcpiUtDivide: Divide by zero\n")); return_ACPI_STATUS (AE_AML_DIVIDE_BY_ZERO); } /* Return only what was requested */ if (OutQuotient) { *OutQuotient = *InDividend / *InDivisor; } if (OutRemainder) { *OutRemainder = *InDividend % *InDivisor; } return_ACPI_STATUS (AE_OK); } #endif