diff options
Diffstat (limited to 'drivers/acpi/acpica/utmath.c')
| -rw-r--r-- | drivers/acpi/acpica/utmath.c | 222 |
1 files changed, 213 insertions, 9 deletions
diff --git a/drivers/acpi/acpica/utmath.c b/drivers/acpi/acpica/utmath.c index aa0502d1d019..5f9c680076c4 100644 --- a/drivers/acpi/acpica/utmath.c +++ b/drivers/acpi/acpica/utmath.c @@ -47,15 +47,6 @@ #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 +60,217 @@ 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 ^= operand_ovl.part.lo; + 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 ^= operand_ovl.part.hi; + 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 +460,7 @@ acpi_ut_divide(u64 in_dividend, } #else + /******************************************************************************* * * FUNCTION: acpi_ut_short_divide, acpi_ut_divide @@ -272,6 +475,7 @@ 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) |