diff --git a/sys/contrib/dev/acpica/CHANGES.txt b/sys/contrib/dev/acpica/CHANGES.txt
index e3f7151f3d96..54057f3752e5 100644
--- a/sys/contrib/dev/acpica/CHANGES.txt
+++ b/sys/contrib/dev/acpica/CHANGES.txt
@@ -1,3 +1,65 @@
+----------------------------------------
+11 March 2004.  Summary of changes for version 20040311:
+
+1) ACPI CA Core Subsystem:
+
+Fixed a problem where errors occurring during the parse phase of
+control method execution did not abort cleanly.  For example,
+objects created and installed in the namespace were not deleted.
+This caused all subsequent invocations of the method to return
+the AE_ALREADY_EXISTS exception.
+
+Implemented a mechanism to force a control method to "Serialized"
+execution if the method attempts to create namespace objects.
+(The root of the AE_ALREADY_EXISTS problem.)
+
+Implemented support for the predefined _OSI "internal" control
+method.  Initial supported strings are "Linux", "Windows 2000",
+"Windows 2001", and "Windows 2001.1", and can be easily upgraded
+for new strings as necessary.  This feature will allow "other"
+operating systems to execute the fully tested, "Windows" code
+path through the ASL code
+
+Global Lock Support:  Now allows multiple acquires and releases
+with any internal thread.  Removed concept of "owning thread" for
+this special mutex.
+
+Fixed two functions that were inappropriately declaring large
+objects on the CPU stack:  PsParseLoop, NsEvaluateRelative.
+Reduces the stack usage during method execution considerably.
+
+Fixed a problem in the ACPI 2.0 FACS descriptor (actbl2.h) where
+the S4Bios_f field was incorrectly defined as UINT32 instead of
+UINT32_BIT.
+
+Fixed a problem where AcpiEvGpeDetect would fault if there were
+no GPEs defined on the machine.
+
+Implemented two runtime options:  One to force all control method
+execution to "Serialized" to mimic Windows behavior, another to
+disable _OSI support if it causes problems on a given machine.
+
+Code and Data Size: Current and previous core subsystem library
+sizes are shown below.  These are the code and data sizes for the
+acpica.lib produced by the Microsoft Visual C++ 6.0 compiler, and
+these values do not include any ACPI driver or OSPM code.  The
+debug version of the code includes the debug output trace
+mechanism and has a much larger code and data size.  Note that
+these values will vary depending on the efficiency of the
+compiler and the compiler options used during generation.
+
+  Previous Release:
+    Non-Debug Version:  74.8K Code,  10.1K Data,   84.9K Total
+    Debug Version:     158.7K Code,  65.1K Data,  223.8K Total
+  Current Release:
+    Non-Debug Version:  76.5K Code,  11.3K Data,   87.8K Total
+    Debug Version:     160.3K Code,  66.0K Data,  226.3K Total
+
+2) iASL Compiler/Disassembler:
+
+Fixed an array size problem for FreeBSD that would cause the
+compiler to fault.
+
 ----------------------------------------
 20 February 2004.  Summary of changes for version 20040220:
 
diff --git a/sys/contrib/dev/acpica/acconfig.h b/sys/contrib/dev/acpica/acconfig.h
index fcbeffd05ef2..b4effcbca27a 100644
--- a/sys/contrib/dev/acpica/acconfig.h
+++ b/sys/contrib/dev/acpica/acconfig.h
@@ -1,7 +1,7 @@
 /******************************************************************************
  *
  * Name: acconfig.h - Global configuration constants
- *       $Revision: 149 $
+ *       $Revision: 150 $
  *
  *****************************************************************************/
 
@@ -137,7 +137,7 @@
 
 /* Version string */
 
-#define ACPI_CA_VERSION                 0x20040220
+#define ACPI_CA_VERSION                 0x20040311
 
 /* Maximum objects in the various object caches */
 
@@ -258,6 +258,10 @@
 
 #define ACPI_SMBUS_BUFFER_SIZE          34
 
+/* Number of strings associated with the _OSI reserved method */
+
+#define ACPI_NUM_OSI_STRINGS            4
+
 
 /******************************************************************************
  *
diff --git a/sys/contrib/dev/acpica/acglobal.h b/sys/contrib/dev/acpica/acglobal.h
index d80bf7d05612..fedc2395dca8 100644
--- a/sys/contrib/dev/acpica/acglobal.h
+++ b/sys/contrib/dev/acpica/acglobal.h
@@ -1,7 +1,7 @@
 /******************************************************************************
  *
  * Name: acglobal.h - Declarations for global variables
- *       $Revision: 147 $
+ *       $Revision: 148 $
  *
  *****************************************************************************/
 
@@ -152,6 +152,14 @@ extern      UINT32                      AcpiDbgLayer;
 
 extern      UINT32                      AcpiGbl_NestingLevel;
 
+/*****************************************************************************
+ *
+ * Runtime configuration
+ *
+ ****************************************************************************/
+
+ACPI_EXTERN UINT8                       AcpiGbl_CreateOsiMethod;
+ACPI_EXTERN UINT8                       AcpiGbl_AllMethodsSerialized;
 
 /*****************************************************************************
  *
@@ -242,6 +250,7 @@ extern const char                      *AcpiGbl_SleepStateNames[ACPI_S_STATE_COU
 extern const char                      *AcpiGbl_HighestDstateNames[4];
 extern const ACPI_OPCODE_INFO           AcpiGbl_AmlOpInfo[AML_NUM_OPCODES];
 extern const char                      *AcpiGbl_RegionTypes[ACPI_NUM_PREDEFINED_REGIONS];
+extern const char                      *AcpiGbl_ValidOsiStrings[ACPI_NUM_OSI_STRINGS];
 
 
 /*****************************************************************************
@@ -252,7 +261,7 @@ extern const char                      *AcpiGbl_RegionTypes[ACPI_NUM_PREDEFINED_
 
 #define NUM_NS_TYPES                    ACPI_TYPE_INVALID+1
 
-#if defined (ACPI_NO_METHOD_EXECUTION) || defined (ACPI_CONSTANT_EVAL_ONLY)
+#if !defined (ACPI_NO_METHOD_EXECUTION) || defined (ACPI_CONSTANT_EVAL_ONLY)
 #define NUM_PREDEFINED_NAMES            10
 #else
 #define NUM_PREDEFINED_NAMES            9
diff --git a/sys/contrib/dev/acpica/acmacros.h b/sys/contrib/dev/acpica/acmacros.h
index 670fe7434e19..3d4f66c8bbfd 100644
--- a/sys/contrib/dev/acpica/acmacros.h
+++ b/sys/contrib/dev/acpica/acmacros.h
@@ -1,7 +1,7 @@
 /******************************************************************************
  *
  * Name: acmacros.h - C macros for the entire subsystem.
- *       $Revision: 148 $
+ *       $Revision: 149 $
  *
  *****************************************************************************/
 
@@ -754,7 +754,4 @@
 
 #endif /* ACPI_DBG_TRACK_ALLOCATIONS */
 
-
-#define ACPI_GET_STACK_POINTER          _asm {mov eax, ebx}
-
 #endif /* ACMACROS_H */
diff --git a/sys/contrib/dev/acpica/acobject.h b/sys/contrib/dev/acpica/acobject.h
index b31eed87f747..dbdb9ef28c6f 100644
--- a/sys/contrib/dev/acpica/acobject.h
+++ b/sys/contrib/dev/acpica/acobject.h
@@ -2,7 +2,7 @@
 /******************************************************************************
  *
  * Name: acobject.h - Definition of ACPI_OPERAND_OBJECT  (Internal object only)
- *       $Revision: 123 $
+ *       $Revision: 124 $
  *
  *****************************************************************************/
 
@@ -259,7 +259,11 @@ typedef struct acpi_object_event
 } ACPI_OBJECT_EVENT;
 
 
-#define INFINITE_CONCURRENCY        0xFF
+#define ACPI_INFINITE_CONCURRENCY   0xFF
+
+typedef
+ACPI_STATUS (*ACPI_INTERNAL_METHOD) (
+    struct acpi_walk_state  *WalkState);
 
 typedef struct acpi_object_method
 {
@@ -269,6 +273,7 @@ typedef struct acpi_object_method
     UINT32                          AmlLength;
     void                            *Semaphore;
     UINT8                           *AmlStart;
+    ACPI_INTERNAL_METHOD            Implementation;
     UINT8                           Concurrency;
     UINT8                           ThreadCount;
     ACPI_OWNER_ID                   OwningId;
diff --git a/sys/contrib/dev/acpica/actbl2.h b/sys/contrib/dev/acpica/actbl2.h
index 6aa1d93ccfcf..932e84f62f3f 100644
--- a/sys/contrib/dev/acpica/actbl2.h
+++ b/sys/contrib/dev/acpica/actbl2.h
@@ -1,7 +1,7 @@
 /******************************************************************************
  *
  * Name: actbl2.h - ACPI Specification Revision 2.0 Tables
- *       $Revision: 35 $
+ *       $Revision: 36 $
  *
  *****************************************************************************/
 
@@ -171,7 +171,7 @@ typedef struct facs_descriptor_rev2
     UINT32                  HardwareSignature;      /* Hardware configuration signature */
     UINT32                  FirmwareWakingVector;   /* 32bit physical address of the Firmware Waking Vector. */
     UINT32                  GlobalLock;             /* Global Lock used to synchronize access to shared hardware resources */
-    UINT32                  S4Bios_f        : 1;    /* S4Bios_f - Indicates if S4BIOS support is present */
+    UINT32_BIT              S4Bios_f        : 1;    /* S4Bios_f - Indicates if S4BIOS support is present */
     UINT32_BIT              Reserved1       : 31;   /* Must be 0 */
     UINT64                  XFirmwareWakingVector;  /* 64bit physical address of the Firmware Waking Vector. */
     UINT8                   Version;                /* Version of this table */
diff --git a/sys/contrib/dev/acpica/actypes.h b/sys/contrib/dev/acpica/actypes.h
index bffcf6bf2994..7e4ea1447301 100644
--- a/sys/contrib/dev/acpica/actypes.h
+++ b/sys/contrib/dev/acpica/actypes.h
@@ -1,7 +1,7 @@
 /******************************************************************************
  *
  * Name: actypes.h - Common data types for the entire ACPI subsystem
- *       $Revision: 264 $
+ *       $Revision: 265 $
  *
  *****************************************************************************/
 
@@ -428,7 +428,6 @@ typedef UINT64                          ACPI_INTEGER;
 /*
  * Power state values
  */
-
 #define ACPI_STATE_UNKNOWN              (UINT8) 0xFF
 
 #define ACPI_STATE_S0                   (UINT8) 0
@@ -472,7 +471,6 @@ typedef UINT64                          ACPI_INTEGER;
 #define ACPI_NOTIFY_BUS_MODE_MISMATCH   (UINT8) 6
 #define ACPI_NOTIFY_POWER_FAULT         (UINT8) 7
 
-
 /*
  *  Table types.  These values are passed to the table related APIs
  */
@@ -488,7 +486,6 @@ typedef UINT32                          ACPI_TABLE_TYPE;
 #define ACPI_TABLE_MAX                  6
 #define NUM_ACPI_TABLE_TYPES            (ACPI_TABLE_MAX+1)
 
-
 /*
  * Types associated with ACPI names and objects.  The first group of
  * values (up to ACPI_TYPE_EXTERNAL_MAX) correspond to the definition
@@ -878,7 +875,7 @@ ACPI_STATUS (*ACPI_INIT_HANDLER) (
 #define ACPI_INIT_DEVICE_INI        1
 
 
-/* Address Spaces (Operation Regions */
+/* Address Spaces (For Operation Regions) */
 
 typedef
 ACPI_STATUS (*ACPI_ADR_SPACE_HANDLER) (
diff --git a/sys/contrib/dev/acpica/acutils.h b/sys/contrib/dev/acpica/acutils.h
index 9f9b6d11cfa7..81e1df894a64 100644
--- a/sys/contrib/dev/acpica/acutils.h
+++ b/sys/contrib/dev/acpica/acutils.h
@@ -1,7 +1,7 @@
 /******************************************************************************
  *
  * Name: acutils.h -- prototypes for the common (subsystem-wide) procedures
- *       $Revision: 159 $
+ *       $Revision: 160 $
  *
  *****************************************************************************/
 
@@ -125,7 +125,6 @@ ACPI_STATUS (*ACPI_PKG_CALLBACK) (
     ACPI_GENERIC_STATE      *State,
     void                    *Context);
 
-
 ACPI_STATUS
 AcpiUtWalkPackageTree (
     ACPI_OPERAND_OBJECT     *SourceObject,
@@ -133,7 +132,6 @@ AcpiUtWalkPackageTree (
     ACPI_PKG_CALLBACK       WalkCallback,
     void                    *Context);
 
-
 typedef struct acpi_pkg_info
 {
     UINT8                   *FreeSpace;
@@ -549,6 +547,10 @@ AcpiUtDeleteInternalObjectList (
 #define METHOD_NAME__PRS        "_PRS"
 
 
+ACPI_STATUS
+AcpiUtOsiImplementation (
+    ACPI_WALK_STATE         *WalkState);
+
 ACPI_STATUS
 AcpiUtEvaluateObject (
     ACPI_NAMESPACE_NODE     *PrefixNode,
diff --git a/sys/contrib/dev/acpica/amlcode.h b/sys/contrib/dev/acpica/amlcode.h
index bb1b6e03a202..dd1f60355b89 100644
--- a/sys/contrib/dev/acpica/amlcode.h
+++ b/sys/contrib/dev/acpica/amlcode.h
@@ -3,7 +3,7 @@
  * Name: amlcode.h - Definitions for AML, as included in "definition blocks"
  *                   Declarations and definitions contained herein are derived
  *                   directly from the ACPI specification.
- *       $Revision: 74 $
+ *       $Revision: 75 $
  *
  *****************************************************************************/
 
@@ -569,11 +569,17 @@ typedef enum
 } AML_ACCESS_ATTRIBUTE;
 
 
-/* bit fields in MethodFlags byte */
+/* Bit fields in MethodFlags byte */
 
-#define METHOD_FLAGS_ARG_COUNT      0x07
-#define METHOD_FLAGS_SERIALIZED     0x08
-#define METHOD_FLAGS_SYNCH_LEVEL    0xF0
+#define AML_METHOD_ARG_COUNT        0x07
+#define AML_METHOD_SERIALIZED       0x08
+#define AML_METHOD_SYNCH_LEVEL      0xF0
+
+/* METHOD_FLAGS_ARG_COUNT is not used internally, define additional flags */
+
+#define AML_METHOD_INTERNAL_ONLY    0x01
+#define AML_METHOD_RESERVED1        0x02
+#define AML_METHOD_RESERVED2        0x04
 
 
 #endif /* __AMLCODE_H__ */
diff --git a/sys/contrib/dev/acpica/compiler/aslutils.c b/sys/contrib/dev/acpica/compiler/aslutils.c
index a33a904f6d6f..b5e50518d3de 100644
--- a/sys/contrib/dev/acpica/compiler/aslutils.c
+++ b/sys/contrib/dev/acpica/compiler/aslutils.c
@@ -2,7 +2,7 @@
 /******************************************************************************
  *
  * Module Name: aslutils -- compiler utilities
- *              $Revision: 57 $
+ *              $Revision: 58 $
  *
  *****************************************************************************/
 
diff --git a/sys/contrib/dev/acpica/dbexec.c b/sys/contrib/dev/acpica/dbexec.c
index 5397ef4aceb1..9eded346e275 100644
--- a/sys/contrib/dev/acpica/dbexec.c
+++ b/sys/contrib/dev/acpica/dbexec.c
@@ -1,7 +1,7 @@
 /*******************************************************************************
  *
  * Module Name: dbexec - debugger control method execution
- *              $Revision: 57 $
+ *              $Revision: 59 $
  *
  ******************************************************************************/
 
@@ -474,12 +474,14 @@ AcpiDbMethodThread (
 #endif
 
         Status = AcpiDbExecuteMethod (Info, &ReturnObj);
-
         if (ACPI_FAILURE (Status))
         {
             AcpiOsPrintf ("%s During execution of %s at iteration %X\n",
                 AcpiFormatException (Status), Info->Pathname, i);
-            break;
+            if (Status == AE_ABORT_METHOD)
+            {
+                break;
+            }
         }
 
         if ((i % 1000) == 0)
diff --git a/sys/contrib/dev/acpica/dsmethod.c b/sys/contrib/dev/acpica/dsmethod.c
index 12275cca459b..f6e69df62e08 100644
--- a/sys/contrib/dev/acpica/dsmethod.c
+++ b/sys/contrib/dev/acpica/dsmethod.c
@@ -1,7 +1,7 @@
 /******************************************************************************
  *
  * Module Name: dsmethod - Parser/Interpreter interface - control method parsing
- *              $Revision: 93 $
+ *              $Revision: 94 $
  *
  *****************************************************************************/
 
@@ -182,7 +182,7 @@ AcpiDsParseMethod (
 
     /* Create a mutex for the method if there is a concurrency limit */
 
-    if ((ObjDesc->Method.Concurrency != INFINITE_CONCURRENCY) &&
+    if ((ObjDesc->Method.Concurrency != ACPI_INFINITE_CONCURRENCY) &&
         (!ObjDesc->Method.Semaphore))
     {
         Status = AcpiOsCreateSemaphore (ObjDesc->Method.Concurrency,
@@ -389,38 +389,42 @@ AcpiDsCallControlMethod (
         return_ACPI_STATUS (Status);
     }
 
-    /* 1) Parse: Create a new walk state for the preempting walk */
-
-    NextWalkState = AcpiDsCreateWalkState (ObjDesc->Method.OwningId,
-                                            Op, ObjDesc, NULL);
-    if (!NextWalkState)
+    if (!(ObjDesc->Method.MethodFlags & AML_METHOD_INTERNAL_ONLY))
     {
-        return_ACPI_STATUS (AE_NO_MEMORY);
+        /* 1) Parse: Create a new walk state for the preempting walk */
+
+        NextWalkState = AcpiDsCreateWalkState (ObjDesc->Method.OwningId,
+                                                Op, ObjDesc, NULL);
+        if (!NextWalkState)
+        {
+            return_ACPI_STATUS (AE_NO_MEMORY);
+        }
+
+
+        /* Create and init a Root Node */
+
+        Op = AcpiPsCreateScopeOp ();
+        if (!Op)
+        {
+            Status = AE_NO_MEMORY;
+            goto Cleanup;
+        }
+
+        Status = AcpiDsInitAmlWalk (NextWalkState, Op, MethodNode,
+                        ObjDesc->Method.AmlStart,  ObjDesc->Method.AmlLength,
+                        NULL, NULL, 1);
+        if (ACPI_FAILURE (Status))
+        {
+            AcpiDsDeleteWalkState (NextWalkState);
+            goto Cleanup;
+        }
+
+        /* Begin AML parse */
+
+        Status = AcpiPsParseAml (NextWalkState);
+        AcpiPsDeleteParseTree (Op);
     }
 
-    /* Create and init a Root Node */
-
-    Op = AcpiPsCreateScopeOp ();
-    if (!Op)
-    {
-        Status = AE_NO_MEMORY;
-        goto Cleanup;
-    }
-
-    Status = AcpiDsInitAmlWalk (NextWalkState, Op, MethodNode,
-                    ObjDesc->Method.AmlStart,  ObjDesc->Method.AmlLength,
-                    NULL, NULL, 1);
-    if (ACPI_FAILURE (Status))
-    {
-        AcpiDsDeleteWalkState (NextWalkState);
-        goto Cleanup;
-    }
-
-    /* Begin AML parse */
-
-    Status = AcpiPsParseAml (NextWalkState);
-    AcpiPsDeleteParseTree (Op);
-
     /* 2) Execute: Create a new state for the preempting walk */
 
     NextWalkState = AcpiDsCreateWalkState (ObjDesc->Method.OwningId,
@@ -430,7 +434,6 @@ AcpiDsCallControlMethod (
         Status = AE_NO_MEMORY;
         goto Cleanup;
     }
-
     /*
      * The resolved arguments were put on the previous walk state's operand
      * stack.  Operands on the previous walk state stack always
@@ -464,16 +467,27 @@ AcpiDsCallControlMethod (
     ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
         "Starting nested execution, newstate=%p\n", NextWalkState));
 
+    if (ObjDesc->Method.MethodFlags & AML_METHOD_INTERNAL_ONLY)
+    {
+        Status = ObjDesc->Method.Implementation (NextWalkState);
+        return_ACPI_STATUS (Status);
+    }
+
     return_ACPI_STATUS (AE_OK);
 
 
     /* On error, we must delete the new walk state */
 
 Cleanup:
+    if (NextWalkState->MethodDesc)
+    {
+        /* Decrement the thread count on the method parse tree */
+
+       NextWalkState->MethodDesc->Method.ThreadCount--;
+    }
     (void) AcpiDsTerminateControlMethod (NextWalkState);
     AcpiDsDeleteWalkState (NextWalkState);
     return_ACPI_STATUS (Status);
-
 }
 
 
@@ -604,11 +618,33 @@ AcpiDsTerminateControlMethod (
         }
     }
 
-    /* Decrement the thread count on the method parse tree */
+    if (WalkState->MethodDesc->Method.ThreadCount)
+    {
+        ACPI_DEBUG_PRINT ((ACPI_DB_DISPATCH,
+            "*** Not deleting method namespace, there are still %d threads\n",
+            WalkState->MethodDesc->Method.ThreadCount));
+    }
 
-    WalkState->MethodDesc->Method.ThreadCount--;
     if (!WalkState->MethodDesc->Method.ThreadCount)
     {
+        /*
+         * Support to dynamically change a method from NotSerialized to
+         * Serialized if it appears that the method is written foolishly and
+         * does not support multiple thread execution.  The best example of this
+         * is if such a method creates namespace objects and blocks.  A second
+         * thread will fail with an AE_ALREADY_EXISTS exception
+         *
+         * This code is here because we must wait until the last thread exits
+         * before creating the synchronization semaphore.
+         */
+        if ((WalkState->MethodDesc->Method.Concurrency == 1) &&
+            (!WalkState->MethodDesc->Method.Semaphore))
+        {
+            Status = AcpiOsCreateSemaphore (1,
+                                    1,
+                                    &WalkState->MethodDesc->Method.Semaphore);
+        }
+
         /*
          * There are no more threads executing this method.  Perform
          * additional cleanup.
diff --git a/sys/contrib/dev/acpica/evgpe.c b/sys/contrib/dev/acpica/evgpe.c
index 4391d83d5001..95978fcbb16b 100644
--- a/sys/contrib/dev/acpica/evgpe.c
+++ b/sys/contrib/dev/acpica/evgpe.c
@@ -1,7 +1,7 @@
 /******************************************************************************
  *
  * Module Name: evgpe - General Purpose Event handling and dispatch
- *              $Revision: 33 $
+ *              $Revision: 34 $
  *
  *****************************************************************************/
 
@@ -228,6 +228,12 @@ AcpiEvGpeDetect (
 
     ACPI_FUNCTION_NAME ("EvGpeDetect");
 
+    /* Check for the case where there are no GPEs */
+
+    if (!GpeXruptList)
+    {
+        return (IntStatus);
+    }
 
     /* Examine all GPE blocks attached to this interrupt level */
 
diff --git a/sys/contrib/dev/acpica/excreate.c b/sys/contrib/dev/acpica/excreate.c
index b0162df6ba7c..8f4be4c36219 100644
--- a/sys/contrib/dev/acpica/excreate.c
+++ b/sys/contrib/dev/acpica/excreate.c
@@ -1,7 +1,7 @@
 /******************************************************************************
  *
  * Module Name: excreate - Named object creation
- *              $Revision: 101 $
+ *              $Revision: 102 $
  *
  *****************************************************************************/
 
@@ -681,29 +681,36 @@ AcpiExCreateMethod (
     ObjDesc->Method.AmlStart  = AmlStart;
     ObjDesc->Method.AmlLength = AmlLength;
 
-    /* disassemble the method flags */
-
+    /*
+     * Disassemble the method flags.  Split off the Arg Count
+     * for efficiency
+     */
     MethodFlags = (UINT8) Operand[1]->Integer.Value;
 
-    ObjDesc->Method.MethodFlags = MethodFlags;
-    ObjDesc->Method.ParamCount  = (UINT8) (MethodFlags & METHOD_FLAGS_ARG_COUNT);
+    ObjDesc->Method.MethodFlags = (UINT8) (MethodFlags & ~AML_METHOD_ARG_COUNT);
+    ObjDesc->Method.ParamCount  = (UINT8) (MethodFlags & AML_METHOD_ARG_COUNT);
 
     /*
      * Get the concurrency count.  If required, a semaphore will be
      * created for this method when it is parsed.
      */
-    if (MethodFlags & METHOD_FLAGS_SERIALIZED)
+    if (AcpiGbl_AllMethodsSerialized)
+    {
+        ObjDesc->Method.Concurrency = 1;
+        ObjDesc->Method.MethodFlags |= AML_METHOD_SERIALIZED;
+    }
+    else if (MethodFlags & AML_METHOD_SERIALIZED)
     {
         /*
          * ACPI 1.0: Concurrency = 1
          * ACPI 2.0: Concurrency = (SyncLevel (in method declaration) + 1)
          */
         ObjDesc->Method.Concurrency = (UINT8)
-                        (((MethodFlags & METHOD_FLAGS_SYNCH_LEVEL) >> 4) + 1);
+                        (((MethodFlags & AML_METHOD_SYNCH_LEVEL) >> 4) + 1);
     }
     else
     {
-        ObjDesc->Method.Concurrency = INFINITE_CONCURRENCY;
+        ObjDesc->Method.Concurrency = ACPI_INFINITE_CONCURRENCY;
     }
 
     /* Attach the new object to the method Node */
diff --git a/sys/contrib/dev/acpica/exmutex.c b/sys/contrib/dev/acpica/exmutex.c
index cd96da31b3be..3c1f4dd03963 100644
--- a/sys/contrib/dev/acpica/exmutex.c
+++ b/sys/contrib/dev/acpica/exmutex.c
@@ -2,7 +2,7 @@
 /******************************************************************************
  *
  * Module Name: exmutex - ASL Mutex Acquire/Release functions
- *              $Revision: 20 $
+ *              $Revision: 21 $
  *
  *****************************************************************************/
 
@@ -258,16 +258,20 @@ AcpiExAcquireMutex (
     /*
      * Support for multiple acquires by the owning thread
      */
-
-    if ((ObjDesc->Mutex.OwnerThread) &&
-        (ObjDesc->Mutex.OwnerThread->ThreadId == WalkState->Thread->ThreadId))
+    if (ObjDesc->Mutex.OwnerThread)
     {
-        /*
-         * The mutex is already owned by this thread,
-         * just increment the acquisition depth
-         */
-        ObjDesc->Mutex.AcquisitionDepth++;
-        return_ACPI_STATUS (AE_OK);
+        /* Special case for Global Lock, allow all threads */
+
+        if ((ObjDesc->Mutex.OwnerThread->ThreadId == WalkState->Thread->ThreadId) ||
+            (ObjDesc->Mutex.Semaphore == AcpiGbl_GlobalLockSemaphore))
+        {
+            /*
+             * The mutex is already owned by this thread,
+             * just increment the acquisition depth
+             */
+            ObjDesc->Mutex.AcquisitionDepth++;
+            return_ACPI_STATUS (AE_OK);
+        }
     }
 
     /* Acquire the mutex, wait if necessary */
@@ -341,9 +345,13 @@ AcpiExReleaseMutex (
         return_ACPI_STATUS (AE_AML_INTERNAL);
     }
 
-    /* The Mutex is owned, but this thread must be the owner */
+    /* 
+     * The Mutex is owned, but this thread must be the owner.
+     * Special case for Global Lock, any thread can release
+     */
+    if ((ObjDesc->Mutex.OwnerThread->ThreadId != WalkState->Thread->ThreadId) &&
+        (ObjDesc->Mutex.Semaphore != AcpiGbl_GlobalLockSemaphore))
 
-    if (ObjDesc->Mutex.OwnerThread->ThreadId != WalkState->Thread->ThreadId)
     {
         ACPI_REPORT_ERROR ((
             "Thread %X cannot release Mutex [%4.4s] acquired by thread %X\n",
diff --git a/sys/contrib/dev/acpica/nsaccess.c b/sys/contrib/dev/acpica/nsaccess.c
index e6554c75b692..a01b22d3a158 100644
--- a/sys/contrib/dev/acpica/nsaccess.c
+++ b/sys/contrib/dev/acpica/nsaccess.c
@@ -1,7 +1,7 @@
 /*******************************************************************************
  *
  * Module Name: nsaccess - Top-level functions for accessing ACPI namespace
- *              $Revision: 177 $
+ *              $Revision: 179 $
  *
  ******************************************************************************/
 
@@ -182,8 +182,16 @@ AcpiNsRootInitialize (void)
 
     for (InitVal = AcpiGbl_PreDefinedNames; InitVal->Name; InitVal++)
     {
+        /* _OSI is optional for now, will be permanent later */
+
+        if (!ACPI_STRCMP (InitVal->Name, "_OSI") && !AcpiGbl_CreateOsiMethod)
+        {
+            continue;
+        }
+
         Status = AcpiNsLookup (NULL, InitVal->Name, InitVal->Type,
-                        ACPI_IMODE_LOAD_PASS2, ACPI_NS_NO_UPSEARCH, NULL, &NewNode);
+                        ACPI_IMODE_LOAD_PASS2, ACPI_NS_NO_UPSEARCH, 
+                        NULL, &NewNode);
 
         if (ACPI_FAILURE (Status) || (!NewNode)) /* Must be on same line for code converter */
         {
@@ -202,7 +210,8 @@ AcpiNsRootInitialize (void)
             Status = AcpiOsPredefinedOverride (InitVal, &Val);
             if (ACPI_FAILURE (Status))
             {
-                ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, "Could not override predefined %s\n",
+                ACPI_DEBUG_PRINT ((ACPI_DB_ERROR, 
+                    "Could not override predefined %s\n",
                     InitVal->Name));
             }
 
@@ -230,15 +239,20 @@ AcpiNsRootInitialize (void)
             switch (InitVal->Type)
             {
             case ACPI_TYPE_METHOD:
-                ObjDesc->Method.ParamCount =
-                        (UINT8) ACPI_STRTOUL (Val, NULL, 10);
+                ObjDesc->Method.ParamCount = (UINT8) ACPI_STRTOUL 
+                                                        (Val, NULL, 10);
                 ObjDesc->Common.Flags |= AOPOBJ_DATA_VALID;
 
-#if defined (ACPI_NO_METHOD_EXECUTION) || defined (ACPI_CONSTANT_EVAL_ONLY)
+#if defined (_ACPI_ASL_COMPILER) || defined (_ACPI_DUMP_APP)
 
-                /* Compiler cheats by putting parameter count in the OwnerID */
+                /* iASL Compiler cheats by putting parameter count in the OwnerID */
 
                 NewNode->OwnerId = ObjDesc->Method.ParamCount;
+#else
+                /* Mark this as a very SPECIAL method */
+
+                ObjDesc->Method.MethodFlags = AML_METHOD_INTERNAL_ONLY;
+                ObjDesc->Method.Implementation = AcpiUtOsiImplementation;
 #endif
                 break;
 
@@ -263,8 +277,8 @@ AcpiNsRootInitialize (void)
             case ACPI_TYPE_MUTEX:
 
                 ObjDesc->Mutex.Node = NewNode;
-                ObjDesc->Mutex.SyncLevel =
-                            (UINT16) ACPI_STRTOUL (Val, NULL, 10);
+                ObjDesc->Mutex.SyncLevel = (UINT16) ACPI_STRTOUL 
+                                                        (Val, NULL, 10);
 
                 if (ACPI_STRCMP (InitVal->Name, "_GL_") == 0)
                 {
@@ -300,6 +314,7 @@ AcpiNsRootInitialize (void)
 
 
             default:
+
                 ACPI_REPORT_ERROR (("Unsupported initial type value %X\n",
                     InitVal->Type));
                 AcpiUtRemoveReference (ObjDesc);
diff --git a/sys/contrib/dev/acpica/nsalloc.c b/sys/contrib/dev/acpica/nsalloc.c
index 4736829f6159..065403c927c4 100644
--- a/sys/contrib/dev/acpica/nsalloc.c
+++ b/sys/contrib/dev/acpica/nsalloc.c
@@ -1,7 +1,7 @@
 /*******************************************************************************
  *
  * Module Name: nsalloc - Namespace allocation and deletion utilities
- *              $Revision: 84 $
+ *              $Revision: 85 $
  *
  ******************************************************************************/
 
@@ -428,10 +428,11 @@ AcpiNsInstallNode (
     Node->OwnerId = OwnerId;
     Node->Type = (UINT8) Type;
 
-    ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, "%4.4s (%s) added to %4.4s (%s) %p at %p\n",
-        AcpiUtGetNodeName (Node), AcpiUtGetTypeName (Node->Type),
+    ACPI_DEBUG_PRINT ((ACPI_DB_NAMES, 
+        "%4.4s (%s) [Node %p Owner %X] added to %4.4s (%s) [Node %p]\n",
+        AcpiUtGetNodeName (Node), AcpiUtGetTypeName (Node->Type), Node, OwnerId,
         AcpiUtGetNodeName (ParentNode), AcpiUtGetTypeName (ParentNode->Type),
-        ParentNode, Node));
+        ParentNode));
 
     /*
      * Increment the reference count(s) of all parents up to
diff --git a/sys/contrib/dev/acpica/nseval.c b/sys/contrib/dev/acpica/nseval.c
index e464f8cb1ab1..cb509d3ae6cc 100644
--- a/sys/contrib/dev/acpica/nseval.c
+++ b/sys/contrib/dev/acpica/nseval.c
@@ -2,7 +2,7 @@
  *
  * Module Name: nseval - Object evaluation interfaces -- includes control
  *                       method lookup and execution.
- *              $Revision: 123 $
+ *              $Revision: 124 $
  *
  ******************************************************************************/
 
@@ -157,11 +157,11 @@ AcpiNsEvaluateRelative (
     ACPI_OPERAND_OBJECT     **Params,
     ACPI_OPERAND_OBJECT     **ReturnObject)
 {
-    ACPI_NAMESPACE_NODE     *PrefixNode;
     ACPI_STATUS             Status;
+    ACPI_NAMESPACE_NODE     *PrefixNode;
     ACPI_NAMESPACE_NODE     *Node = NULL;
+    ACPI_GENERIC_STATE      *ScopeInfo;
     char                    *InternalPath = NULL;
-    ACPI_GENERIC_STATE      ScopeInfo;
 
 
     ACPI_FUNCTION_TRACE ("NsEvaluateRelative");
@@ -183,6 +183,12 @@ AcpiNsEvaluateRelative (
         return_ACPI_STATUS (Status);
     }
 
+    ScopeInfo = AcpiUtCreateGenericState ();
+    if (!ScopeInfo)
+    {
+        goto Cleanup1;
+    }
+
     /* Get the prefix handle and Node */
 
     Status = AcpiUtAcquireMutex (ACPI_MTX_NAMESPACE);
@@ -201,8 +207,8 @@ AcpiNsEvaluateRelative (
 
     /* Lookup the name in the namespace */
 
-    ScopeInfo.Scope.Node = PrefixNode;
-    Status = AcpiNsLookup (&ScopeInfo, InternalPath, ACPI_TYPE_ANY,
+    ScopeInfo->Scope.Node = PrefixNode;
+    Status = AcpiNsLookup (ScopeInfo, InternalPath, ACPI_TYPE_ANY,
                             ACPI_IMODE_EXECUTE, ACPI_NS_NO_UPSEARCH, NULL,
                             &Node);
 
@@ -228,7 +234,9 @@ AcpiNsEvaluateRelative (
         Pathname));
 
 Cleanup:
+    AcpiUtDeleteGenericState (ScopeInfo);
 
+Cleanup1:
     ACPI_MEM_FREE (InternalPath);
     return_ACPI_STATUS (Status);
 }
diff --git a/sys/contrib/dev/acpica/psparse.c b/sys/contrib/dev/acpica/psparse.c
index 44b129306741..5783fa6313fc 100644
--- a/sys/contrib/dev/acpica/psparse.c
+++ b/sys/contrib/dev/acpica/psparse.c
@@ -1,7 +1,7 @@
 /******************************************************************************
  *
  * Module Name: psparse - Parser top level AML parse routines
- *              $Revision: 143 $
+ *              $Revision: 144 $
  *
  *****************************************************************************/
 
@@ -522,7 +522,7 @@ AcpiPsParseLoop (
     ACPI_STATUS             Status = AE_OK;
     ACPI_PARSE_OBJECT       *Op = NULL;     /* current op */
     ACPI_PARSE_OBJECT       *Arg = NULL;
-    ACPI_PARSE_OBJECT       PreOp;
+    ACPI_PARSE_OBJECT       *PreOp = NULL;
     ACPI_PARSE_STATE        *ParserState;
     UINT8                   *AmlOpStart = NULL;
 
@@ -654,8 +654,19 @@ AcpiPsParseLoop (
 
             if (WalkState->OpInfo->Flags & AML_NAMED)
             {
-                PreOp.Common.Value.Arg = NULL;
-                PreOp.Common.AmlOpcode = WalkState->Opcode;
+                /* Allocate a new PreOp if necessary */
+
+                if (!PreOp)
+                {
+                    PreOp = AcpiPsAllocOp (WalkState->Opcode);
+                    if (!PreOp)
+                    {
+                        return_ACPI_STATUS (AE_NO_MEMORY);
+                    }
+                }
+
+                PreOp->Common.Value.Arg = NULL;
+                PreOp->Common.AmlOpcode = WalkState->Opcode;
 
                 /*
                  * Get and append arguments until we find the node that contains
@@ -671,7 +682,7 @@ AcpiPsParseLoop (
                         goto CloseThisOp;
                     }
 
-                    AcpiPsAppendArg (&PreOp, Arg);
+                    AcpiPsAppendArg (PreOp, Arg);
                     INCREMENT_ARG_LIST (WalkState->ArgTypes);
                 }
 
@@ -717,7 +728,7 @@ AcpiPsParseLoop (
                     goto CloseThisOp;
                 }
 
-                AcpiPsAppendArg (Op, PreOp.Common.Value.Arg);
+                AcpiPsAppendArg (Op, PreOp->Common.Value.Arg);
                 AcpiGbl_Depth++;
 
                 if (Op->Common.AmlOpcode == AML_REGION_OP)
@@ -993,6 +1004,11 @@ CloseThisOp:
 
         AcpiPsCompleteThisOp (WalkState, Op);
         Op = NULL;
+        if (PreOp)
+        {
+            AcpiPsFreeOp (PreOp);
+            PreOp = NULL;
+        }
 
         switch (Status)
         {
@@ -1281,6 +1297,30 @@ AcpiPsParseAml (
         {
             ACPI_REPORT_METHOD_ERROR ("Method execution failed",
                 WalkState->MethodNode, NULL, Status);
+
+            /* Check for possible multi-thread reentrancy problem */
+
+            if ((Status == AE_ALREADY_EXISTS) &&
+                (!WalkState->MethodDesc->Method.Semaphore))
+            {
+                /*
+                 * This method is marked NotSerialized, but it tried to create a named
+                 * object, causing the second thread entrance to fail.  We will workaround
+                 * this by marking the method permanently as Serialized.
+                 */
+                WalkState->MethodDesc->Method.MethodFlags |= AML_METHOD_SERIALIZED;
+                WalkState->MethodDesc->Method.Concurrency = 1;
+            }
+        }
+
+        if (WalkState->MethodDesc)
+        {
+            /* Decrement the thread count on the method parse tree */
+
+            if (WalkState->MethodDesc->Method.ThreadCount)
+            {
+                WalkState->MethodDesc->Method.ThreadCount--;
+            }
         }
 
         /* We are done with this walk, move on to the parent if any */
diff --git a/sys/contrib/dev/acpica/psscope.c b/sys/contrib/dev/acpica/psscope.c
index bc1781898019..7fa31c06fbaa 100644
--- a/sys/contrib/dev/acpica/psscope.c
+++ b/sys/contrib/dev/acpica/psscope.c
@@ -1,7 +1,7 @@
 /******************************************************************************
  *
  * Module Name: psscope - Parser scope stack management routines
- *              $Revision: 37 $
+ *              $Revision: 38 $
  *
  *****************************************************************************/
 
@@ -242,7 +242,6 @@ AcpiPsPushScope (
         return_ACPI_STATUS (AE_NO_MEMORY);
     }
 
-
     Scope->Common.DataType         = ACPI_DESC_TYPE_STATE_PSCOPE;
     Scope->ParseScope.Op           = Op;
     Scope->ParseScope.ArgList      = RemainingArgs;
@@ -253,14 +252,12 @@ AcpiPsPushScope (
 
     AcpiUtPushGenericState (&ParserState->Scope, Scope);
 
-
     if (ArgCount == ACPI_VAR_ARGS)
     {
         /* multiple arguments */
 
         Scope->ParseScope.ArgEnd = ParserState->PkgEnd;
     }
-
     else
     {
         /* single argument */
@@ -319,7 +316,6 @@ AcpiPsPopScope (
 
         AcpiUtDeleteGenericState (Scope);
     }
-
     else
     {
         /* empty parse stack, prepare to fetch next opcode */
@@ -329,7 +325,6 @@ AcpiPsPopScope (
         *ArgCount               = 0;
     }
 
-
     ACPI_DEBUG_PRINT ((ACPI_DB_PARSE, "Popped Op %p Args %X\n", *Op, *ArgCount));
     return_VOID;
 }
@@ -354,15 +349,15 @@ AcpiPsCleanupScope (
 {
     ACPI_GENERIC_STATE      *Scope;
 
+
     ACPI_FUNCTION_TRACE_PTR ("PsCleanupScope", ParserState);
 
 
     if (!ParserState)
     {
-        return;
+        return_VOID;
     }
 
-
     /* Delete anything on the scope stack */
 
     while (ParserState->Scope)
diff --git a/sys/contrib/dev/acpica/uteval.c b/sys/contrib/dev/acpica/uteval.c
index cf457869b497..635d711c820a 100644
--- a/sys/contrib/dev/acpica/uteval.c
+++ b/sys/contrib/dev/acpica/uteval.c
@@ -1,7 +1,7 @@
 /******************************************************************************
  *
  * Module Name: uteval - Object evaluation
- *              $Revision: 51 $
+ *              $Revision: 52 $
  *
  *****************************************************************************/
 
@@ -125,6 +125,66 @@
         ACPI_MODULE_NAME    ("uteval")
 
 
+/*******************************************************************************
+ *
+ * FUNCTION:    AcpiUtOsiImplementation
+ *
+ * PARAMETERS:  WalkState           - Current walk state
+ *
+ * RETURN:      Status
+ *
+ * DESCRIPTION: Implementation of _OSI predefined control method
+ *              Supported = _OSI (String)
+ *
+ ******************************************************************************/
+
+ACPI_STATUS
+AcpiUtOsiImplementation (
+    ACPI_WALK_STATE         *WalkState)
+{
+    ACPI_OPERAND_OBJECT     *StringDesc;
+    ACPI_OPERAND_OBJECT     *ReturnDesc;
+    ACPI_NATIVE_UINT        i;
+
+
+    ACPI_FUNCTION_TRACE ("UtOsiImplementation");
+
+
+    /* Validate the string input argument */
+
+    StringDesc = WalkState->Arguments[0].Object;
+    if (!StringDesc || (StringDesc->Common.Type != ACPI_TYPE_STRING))
+    {
+        return_ACPI_STATUS (AE_TYPE);
+    }
+
+    /* Create a return object (Default value = 0) */
+
+    ReturnDesc = AcpiUtCreateInternalObject (ACPI_TYPE_INTEGER);
+    if (!ReturnDesc)
+    {
+        return_ACPI_STATUS (AE_NO_MEMORY);
+    }
+
+    /* Compare input string to table of supported strings */
+
+    for (i = 0; i < ACPI_NUM_OSI_STRINGS; i++)
+    {
+        if (!ACPI_STRCMP (StringDesc->String.Pointer, 
+                            (char *) AcpiGbl_ValidOsiStrings[i]))
+        {
+            /* This string is supported */
+
+            ReturnDesc->Integer.Value = 0xFFFFFFFF;
+            break;
+        }
+    }
+
+    WalkState->ReturnDesc = ReturnDesc;
+    return_ACPI_STATUS (AE_CTRL_TERMINATE);
+}
+
+
 /*******************************************************************************
  *
  * FUNCTION:    AcpiUtEvaluateObject
diff --git a/sys/contrib/dev/acpica/utglobal.c b/sys/contrib/dev/acpica/utglobal.c
index 39ebd58a269e..d3ad37a27c53 100644
--- a/sys/contrib/dev/acpica/utglobal.c
+++ b/sys/contrib/dev/acpica/utglobal.c
@@ -1,7 +1,7 @@
 /******************************************************************************
  *
  * Module Name: utglobal - Global variables for the ACPI subsystem
- *              $Revision: 193 $
+ *              $Revision: 194 $
  *
  *****************************************************************************/
 
@@ -265,6 +265,15 @@ const char                  *AcpiGbl_HighestDstateNames[4] = {
                                 "_S3D",
                                 "_S4D"};
 
+/* Strings supported by the _OSI predefined (internal) method */
+
+const char                  *AcpiGbl_ValidOsiStrings[ACPI_NUM_OSI_STRINGS] = {
+                                "Linux",
+                                "Windows 2000",
+                                "Windows 2001",
+                                "Windows 2001.1"};
+
+
 /******************************************************************************
  *
  * Namespace globals
@@ -275,14 +284,10 @@ const char                  *AcpiGbl_HighestDstateNames[4] = {
 /*
  * Predefined ACPI Names (Built-in to the Interpreter)
  *
- * Initial values are currently supported only for types String and Number.
- * Both are specified as strings in this table.
- *
  * NOTES:
- * 1) _SB_ is defined to be a device to allow _SB_/_INI to be run
+ * 1) _SB_ is defined to be a device to allow \_SB_._INI to be run
  *    during the initialization sequence.
  */
-
 const ACPI_PREDEFINED_NAMES     AcpiGbl_PreDefinedNames[] =
 {
     {"_GPE",    ACPI_TYPE_LOCAL_SCOPE,      NULL},
@@ -294,7 +299,7 @@ const ACPI_PREDEFINED_NAMES     AcpiGbl_PreDefinedNames[] =
     {"_OS_",    ACPI_TYPE_STRING,           ACPI_OS_NAME},
     {"_GL_",    ACPI_TYPE_MUTEX,            "0"},
 
-#if defined (ACPI_NO_METHOD_EXECUTION) || defined (ACPI_CONSTANT_EVAL_ONLY)
+#if !defined (ACPI_NO_METHOD_EXECUTION) || defined (ACPI_CONSTANT_EVAL_ONLY)
     {"_OSI",    ACPI_TYPE_METHOD,           "1"},
 #endif
     {NULL,      ACPI_TYPE_ANY,              NULL}              /* Table terminator */
@@ -305,7 +310,6 @@ const ACPI_PREDEFINED_NAMES     AcpiGbl_PreDefinedNames[] =
  * Properties of the ACPI Object Types, both internal and external.
  * The table is indexed by values of ACPI_OBJECT_TYPE
  */
-
 const UINT8                     AcpiGbl_NsProperties[] =
 {
     ACPI_NS_NORMAL,                     /* 00 Any              */
@@ -384,10 +388,8 @@ AcpiUtHexToAsciiChar (
  *
  ******************************************************************************/
 
-
 ACPI_TABLE_LIST             AcpiGbl_TableLists[NUM_ACPI_TABLE_TYPES];
 
-
 ACPI_TABLE_SUPPORT          AcpiGbl_TableData[NUM_ACPI_TABLE_TYPES] =
 {
     /***********    Name,   Signature, Global typed pointer     Signature size,      Type                  How many allowed?,    Contains valid AML? */
@@ -551,9 +553,8 @@ AcpiUtGetEventName (
  *
  * The type ACPI_TYPE_ANY (Untyped) is used as a "don't care" when searching; when
  * stored in a table it really means that we have thus far seen no evidence to
- * indicatewhat type is actually going to be stored for this entry.
+ * indicate what type is actually going to be stored for this entry.
  */
-
 static const char           AcpiGbl_BadType[] = "UNDEFINED";
 #define TYPE_NAME_LENGTH    12                           /* Maximum length of each string */
 
@@ -858,6 +859,11 @@ AcpiUtInitGlobals (
 
     ACPI_FUNCTION_TRACE ("UtInitGlobals");
 
+    /* Runtime configuration */
+
+    AcpiGbl_CreateOsiMethod = TRUE;
+    AcpiGbl_AllMethodsSerialized = FALSE;
+
     /* Memory allocation and cache lists */
 
     ACPI_MEMSET (AcpiGbl_MemoryLists, 0, sizeof (ACPI_MEMORY_LIST) * ACPI_NUM_MEM_LISTS);