linux/drivers/acpi/acpica/utmath.c

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// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/*******************************************************************************
*
* Module Name: utmath - Integer math support routines
*
******************************************************************************/
#include <acpi/acpi.h>
#include "accommon.h"
#define _COMPONENT ACPI_UTILITIES
ACPI_MODULE_NAME("utmath")
/* Structures used only for 64-bit divide */
typedef struct uint64_struct {
u32 lo;
u32 hi;
} uint64_struct;
typedef union uint64_overlay {
u64 full;
struct uint64_struct part;
} 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
*
* PARAMETERS: dividend - 64-bit dividend
* divisor - 32-bit divisor
* out_quotient - Pointer to where the quotient is returned
* out_remainder - 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
acpi_ut_short_divide(u64 dividend,
u32 divisor, u64 *out_quotient, u32 *out_remainder)
{
union uint64_overlay dividend_ovl;
union uint64_overlay quotient;
u32 remainder32;
ACPI: ACPICA 20060421 Removed a device initialization optimization introduced in 20051216 where the _STA method was not run unless an _INI was also present for the same device. This optimization could cause problems because it could allow _INI methods to be run within a not-present device subtree (If a not-present device had no _INI, _STA would not be run, the not-present status would not be discovered, and the children of the device would be incorrectly traversed.) Implemented a new _STA optimization where namespace subtrees that do not contain _INI are identified and ignored during device initialization. Selectively running _STA can significantly improve boot time on large machines (with assistance from Len Brown.) Implemented support for the device initialization case where the returned _STA flags indicate a device not-present but functioning. In this case, _INI is not run, but the device children are examined for presence, as per the ACPI specification. Implemented an additional change to the IndexField support in order to conform to MS behavior. The value written to the Index Register is not simply a byte offset, it is a byte offset in units of the access width of the parent Index Field. (Fiodor Suietov) Defined and deployed a new OSL interface, acpi_os_validate_address(). This interface is called during the creation of all AML operation regions, and allows the host OS to exert control over what addresses it will allow the AML code to access. Operation Regions whose addresses are disallowed will cause a runtime exception when they are actually accessed (will not affect or abort table loading.) Defined and deployed a new OSL interface, acpi_os_validate_interface(). This interface allows the host OS to match the various "optional" interface/behavior strings for the _OSI predefined control method as appropriate (with assistance from Bjorn Helgaas.) Restructured and corrected various problems in the exception handling code paths within DsCallControlMethod and DsTerminateControlMethod in dsmethod (with assistance from Takayoshi Kochi.) Modified the Linux source converter to ignore quoted string literals while converting identifiers from mixed to lower case. This will correct problems with the disassembler and other areas where such strings must not be modified. The ACPI_FUNCTION_* macros no longer require quotes around the function name. This allows the Linux source converter to convert the names, now that the converter ignores quoted strings. Signed-off-by: Bob Moore <robert.moore@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
2006-04-21 21:15:00 +00:00
ACPI_FUNCTION_TRACE(ut_short_divide);
/* Always check for a zero divisor */
if (divisor == 0) {
[ACPI] ACPICA 20060127 Implemented support in the Resource Manager to allow unresolved namestring references within resource package objects for the _PRT method. This support is in addition to the previously implemented unresolved reference support within the AML parser. If the interpreter slack mode is enabled (true on Linux unless acpi=strict), these unresolved references will be passed through to the caller as a NULL package entry. http://bugzilla.kernel.org/show_bug.cgi?id=5741 Implemented and deployed new macros and functions for error and warning messages across the subsystem. These macros are simpler and generate less code than their predecessors. The new macros ACPI_ERROR, ACPI_EXCEPTION, ACPI_WARNING, and ACPI_INFO replace the ACPI_REPORT_* macros. Implemented the acpi_cpu_flags type to simplify host OS integration of the Acquire/Release Lock OSL interfaces. Suggested by Steven Rostedt and Andrew Morton. Fixed a problem where Alias ASL operators are sometimes not correctly resolved. causing AE_AML_INTERNAL http://bugzilla.kernel.org/show_bug.cgi?id=5189 http://bugzilla.kernel.org/show_bug.cgi?id=5674 Fixed several problems with the implementation of the ConcatenateResTemplate ASL operator. As per the ACPI specification, zero length buffers are now treated as a single EndTag. One-length buffers always cause a fatal exception. Non-zero length buffers that do not end with a full 2-byte EndTag cause a fatal exception. Fixed a possible structure overwrite in the AcpiGetObjectInfo external interface. (With assistance from Thomas Renninger) Signed-off-by: Bob Moore <robert.moore@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
2006-01-27 21:43:00 +00:00
ACPI_ERROR((AE_INFO, "Divide by zero"));
return_ACPI_STATUS(AE_AML_DIVIDE_BY_ZERO);
}
dividend_ovl.full = dividend;
/*
* 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_ovl.part.hi, divisor,
quotient.part.hi, remainder32);
ACPI_DIV_64_BY_32(remainder32, dividend_ovl.part.lo, divisor,
quotient.part.lo, remainder32);
/* Return only what was requested */
if (out_quotient) {
*out_quotient = quotient.full;
}
if (out_remainder) {
*out_remainder = remainder32;
}
return_ACPI_STATUS(AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_ut_divide
*
* PARAMETERS: in_dividend - Dividend
* in_divisor - Divisor
* out_quotient - Pointer to where the quotient is returned
* out_remainder - Pointer to where the remainder is returned
*
* RETURN: Status (Checks for divide-by-zero)
*
* DESCRIPTION: Perform a divide and modulo.
*
******************************************************************************/
acpi_status
acpi_ut_divide(u64 in_dividend,
u64 in_divisor, u64 *out_quotient, u64 *out_remainder)
{
union uint64_overlay dividend;
union uint64_overlay divisor;
union uint64_overlay quotient;
union uint64_overlay remainder;
union uint64_overlay normalized_dividend;
union uint64_overlay normalized_divisor;
u32 partial1;
union uint64_overlay partial2;
union uint64_overlay partial3;
ACPI: ACPICA 20060421 Removed a device initialization optimization introduced in 20051216 where the _STA method was not run unless an _INI was also present for the same device. This optimization could cause problems because it could allow _INI methods to be run within a not-present device subtree (If a not-present device had no _INI, _STA would not be run, the not-present status would not be discovered, and the children of the device would be incorrectly traversed.) Implemented a new _STA optimization where namespace subtrees that do not contain _INI are identified and ignored during device initialization. Selectively running _STA can significantly improve boot time on large machines (with assistance from Len Brown.) Implemented support for the device initialization case where the returned _STA flags indicate a device not-present but functioning. In this case, _INI is not run, but the device children are examined for presence, as per the ACPI specification. Implemented an additional change to the IndexField support in order to conform to MS behavior. The value written to the Index Register is not simply a byte offset, it is a byte offset in units of the access width of the parent Index Field. (Fiodor Suietov) Defined and deployed a new OSL interface, acpi_os_validate_address(). This interface is called during the creation of all AML operation regions, and allows the host OS to exert control over what addresses it will allow the AML code to access. Operation Regions whose addresses are disallowed will cause a runtime exception when they are actually accessed (will not affect or abort table loading.) Defined and deployed a new OSL interface, acpi_os_validate_interface(). This interface allows the host OS to match the various "optional" interface/behavior strings for the _OSI predefined control method as appropriate (with assistance from Bjorn Helgaas.) Restructured and corrected various problems in the exception handling code paths within DsCallControlMethod and DsTerminateControlMethod in dsmethod (with assistance from Takayoshi Kochi.) Modified the Linux source converter to ignore quoted string literals while converting identifiers from mixed to lower case. This will correct problems with the disassembler and other areas where such strings must not be modified. The ACPI_FUNCTION_* macros no longer require quotes around the function name. This allows the Linux source converter to convert the names, now that the converter ignores quoted strings. Signed-off-by: Bob Moore <robert.moore@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
2006-04-21 21:15:00 +00:00
ACPI_FUNCTION_TRACE(ut_divide);
/* Always check for a zero divisor */
if (in_divisor == 0) {
[ACPI] ACPICA 20060127 Implemented support in the Resource Manager to allow unresolved namestring references within resource package objects for the _PRT method. This support is in addition to the previously implemented unresolved reference support within the AML parser. If the interpreter slack mode is enabled (true on Linux unless acpi=strict), these unresolved references will be passed through to the caller as a NULL package entry. http://bugzilla.kernel.org/show_bug.cgi?id=5741 Implemented and deployed new macros and functions for error and warning messages across the subsystem. These macros are simpler and generate less code than their predecessors. The new macros ACPI_ERROR, ACPI_EXCEPTION, ACPI_WARNING, and ACPI_INFO replace the ACPI_REPORT_* macros. Implemented the acpi_cpu_flags type to simplify host OS integration of the Acquire/Release Lock OSL interfaces. Suggested by Steven Rostedt and Andrew Morton. Fixed a problem where Alias ASL operators are sometimes not correctly resolved. causing AE_AML_INTERNAL http://bugzilla.kernel.org/show_bug.cgi?id=5189 http://bugzilla.kernel.org/show_bug.cgi?id=5674 Fixed several problems with the implementation of the ConcatenateResTemplate ASL operator. As per the ACPI specification, zero length buffers are now treated as a single EndTag. One-length buffers always cause a fatal exception. Non-zero length buffers that do not end with a full 2-byte EndTag cause a fatal exception. Fixed a possible structure overwrite in the AcpiGetObjectInfo external interface. (With assistance from Thomas Renninger) Signed-off-by: Bob Moore <robert.moore@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
2006-01-27 21:43:00 +00:00
ACPI_ERROR((AE_INFO, "Divide by zero"));
return_ACPI_STATUS(AE_AML_DIVIDE_BY_ZERO);
}
divisor.full = in_divisor;
dividend.full = in_dividend;
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;
normalized_dividend = dividend;
normalized_divisor = divisor;
/* Normalize the operands (shift until the divisor is < 32 bits) */
do {
ACPI_SHIFT_RIGHT_64(normalized_divisor.part.hi,
normalized_divisor.part.lo);
ACPI_SHIFT_RIGHT_64(normalized_dividend.part.hi,
normalized_dividend.part.lo);
} while (normalized_divisor.part.hi != 0);
/* Partial divide */
ACPI_DIV_64_BY_32(normalized_dividend.part.hi,
normalized_dividend.part.lo,
normalized_divisor.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 = (u64) quotient.part.lo * divisor.part.lo;
partial3.full = (u64) 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 = (u32)-((s32)remainder.part.hi);
remainder.part.lo = (u32)-((s32)remainder.part.lo);
if (remainder.part.lo) {
remainder.part.hi--;
}
}
}
/* Return only what was requested */
if (out_quotient) {
*out_quotient = quotient.full;
}
if (out_remainder) {
*out_remainder = remainder.full;
}
return_ACPI_STATUS(AE_OK);
}
#else
/*******************************************************************************
*
* FUNCTION: acpi_ut_short_divide, acpi_ut_divide
*
ACPICA 20050408 from Bob Moore Fixed three cases in the interpreter where an "index" argument to an ASL function was still (internally) 32 bits instead of the required 64 bits. This was the Index argument to the Index, Mid, and Match operators. The "strupr" function is now permanently local (acpi_ut_strupr), since this is not a POSIX-defined function and not present in most kernel-level C libraries. References to the C library strupr function have been removed from the headers. Completed the deployment of static functions/prototypes. All prototypes with the static attribute have been moved from the headers to the owning C file. ACPICA 20050329 from Bob Moore An error is now generated if an attempt is made to create a Buffer Field of length zero (A CreateField with a length operand of zero.) The interpreter now issues a warning whenever executable code at the module level is detected during ACPI table load. This will give some idea of the prevalence of this type of code. Implemented support for references to named objects (other than control methods) within package objects. Enhanced package object output for the debug object. Package objects are now completely dumped, showing all elements. Enhanced miscellaneous object output for the debug object. Any object can now be written to the debug object (for example, a device object can be written, and the type of the object will be displayed.) The "static" qualifier has been added to all local functions across the core subsystem. The number of "long" lines (> 80 chars) within the source has been significantly reduced, by about 1/3. Cleaned up all header files to ensure that all CA/iASL functions are prototyped (even static functions) and the formatting is consistent. Two new header files have been added, acopcode.h and acnames.h. Removed several obsolete functions that were no longer used. Signed-off-by: Len Brown <len.brown@intel.com>
2005-04-19 02:49:35 +00:00
* PARAMETERS: See function headers above
*
* DESCRIPTION: Native versions of the ut_divide 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
acpi_ut_short_divide(u64 in_dividend,
u32 divisor, u64 *out_quotient, u32 *out_remainder)
{
ACPI: ACPICA 20060421 Removed a device initialization optimization introduced in 20051216 where the _STA method was not run unless an _INI was also present for the same device. This optimization could cause problems because it could allow _INI methods to be run within a not-present device subtree (If a not-present device had no _INI, _STA would not be run, the not-present status would not be discovered, and the children of the device would be incorrectly traversed.) Implemented a new _STA optimization where namespace subtrees that do not contain _INI are identified and ignored during device initialization. Selectively running _STA can significantly improve boot time on large machines (with assistance from Len Brown.) Implemented support for the device initialization case where the returned _STA flags indicate a device not-present but functioning. In this case, _INI is not run, but the device children are examined for presence, as per the ACPI specification. Implemented an additional change to the IndexField support in order to conform to MS behavior. The value written to the Index Register is not simply a byte offset, it is a byte offset in units of the access width of the parent Index Field. (Fiodor Suietov) Defined and deployed a new OSL interface, acpi_os_validate_address(). This interface is called during the creation of all AML operation regions, and allows the host OS to exert control over what addresses it will allow the AML code to access. Operation Regions whose addresses are disallowed will cause a runtime exception when they are actually accessed (will not affect or abort table loading.) Defined and deployed a new OSL interface, acpi_os_validate_interface(). This interface allows the host OS to match the various "optional" interface/behavior strings for the _OSI predefined control method as appropriate (with assistance from Bjorn Helgaas.) Restructured and corrected various problems in the exception handling code paths within DsCallControlMethod and DsTerminateControlMethod in dsmethod (with assistance from Takayoshi Kochi.) Modified the Linux source converter to ignore quoted string literals while converting identifiers from mixed to lower case. This will correct problems with the disassembler and other areas where such strings must not be modified. The ACPI_FUNCTION_* macros no longer require quotes around the function name. This allows the Linux source converter to convert the names, now that the converter ignores quoted strings. Signed-off-by: Bob Moore <robert.moore@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
2006-04-21 21:15:00 +00:00
ACPI_FUNCTION_TRACE(ut_short_divide);
/* Always check for a zero divisor */
if (divisor == 0) {
[ACPI] ACPICA 20060127 Implemented support in the Resource Manager to allow unresolved namestring references within resource package objects for the _PRT method. This support is in addition to the previously implemented unresolved reference support within the AML parser. If the interpreter slack mode is enabled (true on Linux unless acpi=strict), these unresolved references will be passed through to the caller as a NULL package entry. http://bugzilla.kernel.org/show_bug.cgi?id=5741 Implemented and deployed new macros and functions for error and warning messages across the subsystem. These macros are simpler and generate less code than their predecessors. The new macros ACPI_ERROR, ACPI_EXCEPTION, ACPI_WARNING, and ACPI_INFO replace the ACPI_REPORT_* macros. Implemented the acpi_cpu_flags type to simplify host OS integration of the Acquire/Release Lock OSL interfaces. Suggested by Steven Rostedt and Andrew Morton. Fixed a problem where Alias ASL operators are sometimes not correctly resolved. causing AE_AML_INTERNAL http://bugzilla.kernel.org/show_bug.cgi?id=5189 http://bugzilla.kernel.org/show_bug.cgi?id=5674 Fixed several problems with the implementation of the ConcatenateResTemplate ASL operator. As per the ACPI specification, zero length buffers are now treated as a single EndTag. One-length buffers always cause a fatal exception. Non-zero length buffers that do not end with a full 2-byte EndTag cause a fatal exception. Fixed a possible structure overwrite in the AcpiGetObjectInfo external interface. (With assistance from Thomas Renninger) Signed-off-by: Bob Moore <robert.moore@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
2006-01-27 21:43:00 +00:00
ACPI_ERROR((AE_INFO, "Divide by zero"));
return_ACPI_STATUS(AE_AML_DIVIDE_BY_ZERO);
}
/* Return only what was requested */
if (out_quotient) {
*out_quotient = in_dividend / divisor;
}
if (out_remainder) {
*out_remainder = (u32) (in_dividend % divisor);
}
return_ACPI_STATUS(AE_OK);
}
acpi_status
acpi_ut_divide(u64 in_dividend,
u64 in_divisor, u64 *out_quotient, u64 *out_remainder)
{
ACPI: ACPICA 20060421 Removed a device initialization optimization introduced in 20051216 where the _STA method was not run unless an _INI was also present for the same device. This optimization could cause problems because it could allow _INI methods to be run within a not-present device subtree (If a not-present device had no _INI, _STA would not be run, the not-present status would not be discovered, and the children of the device would be incorrectly traversed.) Implemented a new _STA optimization where namespace subtrees that do not contain _INI are identified and ignored during device initialization. Selectively running _STA can significantly improve boot time on large machines (with assistance from Len Brown.) Implemented support for the device initialization case where the returned _STA flags indicate a device not-present but functioning. In this case, _INI is not run, but the device children are examined for presence, as per the ACPI specification. Implemented an additional change to the IndexField support in order to conform to MS behavior. The value written to the Index Register is not simply a byte offset, it is a byte offset in units of the access width of the parent Index Field. (Fiodor Suietov) Defined and deployed a new OSL interface, acpi_os_validate_address(). This interface is called during the creation of all AML operation regions, and allows the host OS to exert control over what addresses it will allow the AML code to access. Operation Regions whose addresses are disallowed will cause a runtime exception when they are actually accessed (will not affect or abort table loading.) Defined and deployed a new OSL interface, acpi_os_validate_interface(). This interface allows the host OS to match the various "optional" interface/behavior strings for the _OSI predefined control method as appropriate (with assistance from Bjorn Helgaas.) Restructured and corrected various problems in the exception handling code paths within DsCallControlMethod and DsTerminateControlMethod in dsmethod (with assistance from Takayoshi Kochi.) Modified the Linux source converter to ignore quoted string literals while converting identifiers from mixed to lower case. This will correct problems with the disassembler and other areas where such strings must not be modified. The ACPI_FUNCTION_* macros no longer require quotes around the function name. This allows the Linux source converter to convert the names, now that the converter ignores quoted strings. Signed-off-by: Bob Moore <robert.moore@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
2006-04-21 21:15:00 +00:00
ACPI_FUNCTION_TRACE(ut_divide);
/* Always check for a zero divisor */
if (in_divisor == 0) {
[ACPI] ACPICA 20060127 Implemented support in the Resource Manager to allow unresolved namestring references within resource package objects for the _PRT method. This support is in addition to the previously implemented unresolved reference support within the AML parser. If the interpreter slack mode is enabled (true on Linux unless acpi=strict), these unresolved references will be passed through to the caller as a NULL package entry. http://bugzilla.kernel.org/show_bug.cgi?id=5741 Implemented and deployed new macros and functions for error and warning messages across the subsystem. These macros are simpler and generate less code than their predecessors. The new macros ACPI_ERROR, ACPI_EXCEPTION, ACPI_WARNING, and ACPI_INFO replace the ACPI_REPORT_* macros. Implemented the acpi_cpu_flags type to simplify host OS integration of the Acquire/Release Lock OSL interfaces. Suggested by Steven Rostedt and Andrew Morton. Fixed a problem where Alias ASL operators are sometimes not correctly resolved. causing AE_AML_INTERNAL http://bugzilla.kernel.org/show_bug.cgi?id=5189 http://bugzilla.kernel.org/show_bug.cgi?id=5674 Fixed several problems with the implementation of the ConcatenateResTemplate ASL operator. As per the ACPI specification, zero length buffers are now treated as a single EndTag. One-length buffers always cause a fatal exception. Non-zero length buffers that do not end with a full 2-byte EndTag cause a fatal exception. Fixed a possible structure overwrite in the AcpiGetObjectInfo external interface. (With assistance from Thomas Renninger) Signed-off-by: Bob Moore <robert.moore@intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
2006-01-27 21:43:00 +00:00
ACPI_ERROR((AE_INFO, "Divide by zero"));
return_ACPI_STATUS(AE_AML_DIVIDE_BY_ZERO);
}
/* Return only what was requested */
if (out_quotient) {
*out_quotient = in_dividend / in_divisor;
}
if (out_remainder) {
*out_remainder = in_dividend % in_divisor;
}
return_ACPI_STATUS(AE_OK);
}
#endif