diff options
Diffstat (limited to 'drivers/acpi/acpica/utmath.c')
| -rw-r--r-- | drivers/acpi/acpica/utmath.c | 260 |
1 files changed, 214 insertions, 46 deletions
diff --git a/drivers/acpi/acpica/utmath.c b/drivers/acpi/acpica/utmath.c index aa0502d1d019..2c2c6bc1ff3f 100644 --- a/drivers/acpi/acpica/utmath.c +++ b/drivers/acpi/acpica/utmath.c @@ -1,61 +1,16 @@ +// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0 /******************************************************************************* * * Module Name: utmath - Integer math support routines * ******************************************************************************/ -/* - * Copyright (C) 2000 - 2017, Intel Corp. - * All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions - * are met: - * 1. Redistributions of source code must retain the above copyright - * notice, this list of conditions, and the following disclaimer, - * without modification. - * 2. Redistributions in binary form must reproduce at minimum a disclaimer - * substantially similar to the "NO WARRANTY" disclaimer below - * ("Disclaimer") and any redistribution must be conditioned upon - * including a substantially similar Disclaimer requirement for further - * binary redistribution. - * 3. Neither the names of the above-listed copyright holders nor the names - * of any contributors may be used to endorse or promote products derived - * from this software without specific prior written permission. - * - * Alternatively, this software may be distributed under the terms of the - * GNU General Public License ("GPL") version 2 as published by the Free - * Software Foundation. - * - * NO WARRANTY - * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS - * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT - * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR - * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT - * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL - * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS - * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) - * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, - * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING - * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE - * POSSIBILITY OF SUCH DAMAGES. - */ - #include <acpi/acpi.h> #include "accommon.h" #define _COMPONENT ACPI_UTILITIES ACPI_MODULE_NAME("utmath") -/* - * Optional support for 64-bit double-precision integer divide. This code - * is configurable and is implemented in order to support 32-bit kernel - * environments where a 64-bit double-precision math library is not available. - * - * Support for a more normal 64-bit divide/modulo (with check for a divide- - * by-zero) appears after this optional section of code. - */ -#ifndef ACPI_USE_NATIVE_DIVIDE /* Structures used only for 64-bit divide */ typedef struct uint64_struct { u32 lo; @@ -69,6 +24,217 @@ typedef union uint64_overlay { } uint64_overlay; +/* + * Optional support for 64-bit double-precision integer multiply and shift. + * This code is configurable and is implemented in order to support 32-bit + * kernel environments where a 64-bit double-precision math library is not + * available. + */ +#ifndef ACPI_USE_NATIVE_MATH64 + +/******************************************************************************* + * + * FUNCTION: acpi_ut_short_multiply + * + * PARAMETERS: multiplicand - 64-bit multiplicand + * multiplier - 32-bit multiplier + * out_product - Pointer to where the product is returned + * + * DESCRIPTION: Perform a short multiply. + * + ******************************************************************************/ + +acpi_status +acpi_ut_short_multiply(u64 multiplicand, u32 multiplier, u64 *out_product) +{ + union uint64_overlay multiplicand_ovl; + union uint64_overlay product; + u32 carry32; + + ACPI_FUNCTION_TRACE(ut_short_multiply); + + multiplicand_ovl.full = multiplicand; + + /* + * The Product is 64 bits, the carry is always 32 bits, + * and is generated by the second multiply. + */ + ACPI_MUL_64_BY_32(0, multiplicand_ovl.part.hi, multiplier, + product.part.hi, carry32); + + ACPI_MUL_64_BY_32(0, multiplicand_ovl.part.lo, multiplier, + product.part.lo, carry32); + + product.part.hi += carry32; + + /* Return only what was requested */ + + if (out_product) { + *out_product = product.full; + } + + return_ACPI_STATUS(AE_OK); +} + +/******************************************************************************* + * + * FUNCTION: acpi_ut_short_shift_left + * + * PARAMETERS: operand - 64-bit shift operand + * count - 32-bit shift count + * out_result - Pointer to where the result is returned + * + * DESCRIPTION: Perform a short left shift. + * + ******************************************************************************/ + +acpi_status acpi_ut_short_shift_left(u64 operand, u32 count, u64 *out_result) +{ + union uint64_overlay operand_ovl; + + ACPI_FUNCTION_TRACE(ut_short_shift_left); + + operand_ovl.full = operand; + + if ((count & 63) >= 32) { + operand_ovl.part.hi = operand_ovl.part.lo; + operand_ovl.part.lo = 0; + count = (count & 63) - 32; + } + ACPI_SHIFT_LEFT_64_BY_32(operand_ovl.part.hi, + operand_ovl.part.lo, count); + + /* Return only what was requested */ + + if (out_result) { + *out_result = operand_ovl.full; + } + + return_ACPI_STATUS(AE_OK); +} + +/******************************************************************************* + * + * FUNCTION: acpi_ut_short_shift_right + * + * PARAMETERS: operand - 64-bit shift operand + * count - 32-bit shift count + * out_result - Pointer to where the result is returned + * + * DESCRIPTION: Perform a short right shift. + * + ******************************************************************************/ + +acpi_status acpi_ut_short_shift_right(u64 operand, u32 count, u64 *out_result) +{ + union uint64_overlay operand_ovl; + + ACPI_FUNCTION_TRACE(ut_short_shift_right); + + operand_ovl.full = operand; + + if ((count & 63) >= 32) { + operand_ovl.part.lo = operand_ovl.part.hi; + operand_ovl.part.hi = 0; + count = (count & 63) - 32; + } + ACPI_SHIFT_RIGHT_64_BY_32(operand_ovl.part.hi, + operand_ovl.part.lo, count); + + /* Return only what was requested */ + + if (out_result) { + *out_result = operand_ovl.full; + } + + return_ACPI_STATUS(AE_OK); +} +#else + +/******************************************************************************* + * + * FUNCTION: acpi_ut_short_multiply + * + * PARAMETERS: See function headers above + * + * DESCRIPTION: Native version of the ut_short_multiply function. + * + ******************************************************************************/ + +acpi_status +acpi_ut_short_multiply(u64 multiplicand, u32 multiplier, u64 *out_product) +{ + + ACPI_FUNCTION_TRACE(ut_short_multiply); + + /* Return only what was requested */ + + if (out_product) { + *out_product = multiplicand * multiplier; + } + + return_ACPI_STATUS(AE_OK); +} + +/******************************************************************************* + * + * FUNCTION: acpi_ut_short_shift_left + * + * PARAMETERS: See function headers above + * + * DESCRIPTION: Native version of the ut_short_shift_left function. + * + ******************************************************************************/ + +acpi_status acpi_ut_short_shift_left(u64 operand, u32 count, u64 *out_result) +{ + + ACPI_FUNCTION_TRACE(ut_short_shift_left); + + /* Return only what was requested */ + + if (out_result) { + *out_result = operand << count; + } + + return_ACPI_STATUS(AE_OK); +} + +/******************************************************************************* + * + * FUNCTION: acpi_ut_short_shift_right + * + * PARAMETERS: See function headers above + * + * DESCRIPTION: Native version of the ut_short_shift_right function. + * + ******************************************************************************/ + +acpi_status acpi_ut_short_shift_right(u64 operand, u32 count, u64 *out_result) +{ + + ACPI_FUNCTION_TRACE(ut_short_shift_right); + + /* Return only what was requested */ + + if (out_result) { + *out_result = operand >> count; + } + + return_ACPI_STATUS(AE_OK); +} +#endif + +/* + * Optional support for 64-bit double-precision integer divide. This code + * is configurable and is implemented in order to support 32-bit kernel + * environments where a 64-bit double-precision math library is not available. + * + * Support for a more normal 64-bit divide/modulo (with check for a divide- + * by-zero) appears after this optional section of code. + */ +#ifndef ACPI_USE_NATIVE_DIVIDE + /******************************************************************************* * * FUNCTION: acpi_ut_short_divide @@ -258,6 +424,7 @@ acpi_ut_divide(u64 in_dividend, } #else + /******************************************************************************* * * FUNCTION: acpi_ut_short_divide, acpi_ut_divide @@ -272,6 +439,7 @@ acpi_ut_divide(u64 in_dividend, * perform the divide. * ******************************************************************************/ + acpi_status acpi_ut_short_divide(u64 in_dividend, u32 divisor, u64 *out_quotient, u32 *out_remainder) |