ACPICA version 20090521 released

[Moore, Robert]

21 May 2009. Summary of changes for version 20090521:

This release is available at www.acpica.org/downloads

1) ACPI CA Core Subsystem:

Disabled the preservation of the SCI enable bit in the PM1 control register. The SCI enable bit (bit 0, SCI_EN) is defined by the ACPI specification to be a "preserved" bit - "OSPM always preserves this bit position", section 4.7.3.2.1. However, some machines fail if this bit is in fact preserved because the bit needs to be explicitly set by the OS as a workaround. No machines fail if the bit is not preserved. Therefore, ACPICA no longer attempts to preserve this bit.

Fixed a problem in AcpiRsGetPciRoutingTableLength where an invalid or incorrectly formed _PRT package could cause a fault. Added validation to ensure that each package element is actually a sub-package.

Implemented a new interface to install or override a single control method, AcpiInstallMethod. This interface is useful when debugging in order to repair an existing method or to install a missing method without having to override the entire ACPI table. See the ACPICA Programmer Reference for use and examples. Lin Ming, Bob Moore.

Fixed several reference count issues with the DdbHandle object that is created from a Load or LoadTable operator. Prevent premature deletion of the object. Also, mark the object as invalid once the table has been unloaded. This is needed because the handle itself may not be deleted after the table unload, depending on whether it has been stored in a named object by the caller. Lin Ming.

Fixed a problem with Mutex Sync Levels. Fixed a problem where if multiple mutexes of the same sync level are acquired but then not released in strict opposite order, the internally maintained Current Sync Level becomes confused and can cause subsequent execution errors. ACPICA BZ 471.

Changed the allowable release order for ASL mutex objects. The ACPI 4.0 specification has been changed to make the SyncLevel for mutex objects more useful. When releasing a mutex, the SyncLevel of the mutex must now be the same as the current sync level. This makes more sense than the previous rule (SyncLevel less than or equal). This change updates the code to match the specification.

Fixed a problem with the local version of the AcpiOsPurgeCache function. The (local) cache must be locked during all cache object deletions. Andrew Baumann.

Updated the Load operator to use operation region interfaces. This replaces direct memory mapping with region access calls. Now, all region accesses go through the installed region handler as they should.

Simplified and optimized the NsGetNextNode function. Reduced parameter count and reduced code for this frequently used function.

Example Code and Data Size: These are the sizes for the OS-independent acpica.lib produced by the Microsoft Visual C++ 6.0 32-bit compiler. The debug version of the code includes the debug output trace mechanism and has a much larger code and data size.

  Previous Release:
    Non-Debug Version:  82.8K Code, 17.5K Data, 100.3K Total
    Debug Version:     158.0K Code, 49.9K Data, 207.9K Total
  Current Release:
    Non-Debug Version:  83.4K Code, 17.5K Data, 100.9K Total
    Debug Version:     158.9K Code, 50.0K Data, 208.9K Total

2) iASL Compiler/Disassembler and Tools:

Disassembler: Fixed some issues with DMAR, HEST, MADT tables. Some problems with sub-table disassembly and handling invalid sub-tables. Attempt recovery after an invalid sub-table ID.