WebSVN – Kolibri OS – Diff – /drivers/devman/acpica/compiler/aslresource.c

 /******************************************************************************
+ *
  * 1. Copyright Notice
+ *
- * Some or all of this work - Copyright (c) 1999 - 2010, Intel Corp.
+ * Some or all of this work - Copyright (c) 1999 - 2011, Intel Corp.
  * All rights reserved.
+ *
  * 2. License
+ *
  * 2.1. This is your license from Intel Corp. under its intellectual property
  *              AlignOp             - Original Op for address alignment. If
  *                                    NULL, means "zero value for alignment is
  *                                    OK, and means 64K alignment" (for
  *                                    Memory24 descriptor)
  *              Op                  - Parent Op for entire construct
+ *
  * RETURN:      None. Adds error messages to error log if necessary
+ *
  * DESCRIPTION: Perform common value checks for "small" address descriptors.
  *              Currently:
  *                  Io, Memory24, Memory32
     UINT32                  Alignment,
     ACPI_PARSE_OBJECT       *MinOp,
     ACPI_PARSE_OBJECT       *MaxOp,
     ACPI_PARSE_OBJECT       *LengthOp,
-    ACPI_PARSE_OBJECT       *AlignOp)
+    ACPI_PARSE_OBJECT       *AlignOp,
-{
+    ACPI_PARSE_OBJECT       *Op)
+{
     if (Gbl_NoResourceChecking)
+    {
         return;
+    }
+    /*
+     * Check for a so-called "null descriptor". These are descriptors that are
+     * created with most fields set to zero. The intent is that the descriptor
+     * will be updated/completed at runtime via a BufferField.
+     *
+     * If the descriptor does NOT have a resource tag, it cannot be referenced
+     * by a BufferField and we will flag this as an error. Conversely, if
+     * the descriptor has a resource tag, we will assume that a BufferField
+     * will be used to dynamically update it, so no error.
+     *
+     * A possible enhancement to this check would be to verify that in fact
+     * a BufferField is created using the resource tag, and perhaps even
+     * verify that a Store is performed to the BufferField.
+     *
+     * Note: for these descriptors, Alignment is allowed to be zero
+     */
+    if (!Minimum && !Maximum && !Length)
+    {
+        if (!Op->Asl.ExternalName)
+        {
+            /* No resource tag. Descriptor is fixed and is also illegal */
+            AslError (ASL_ERROR, ASL_MSG_NULL_DESCRIPTOR, Op, NULL);
+        }
+        return;
+    }
     /* Special case for Memory24, values are compressed */
     if (Type == ACPI_RESOURCE_NAME_MEMORY24)
  *              MinOp               - Original Op for Address Min
  *              MaxOp               - Original Op for Address Max
  *              LengthOp            - Original Op for address range
  *              GranOp              - Original Op for address granularity
  *              Op                  - Parent Op for entire construct
+ *
  * RETURN:      None. Adds error messages to error log if necessary
+ *
  * DESCRIPTION: Perform common value checks for "large" address descriptors.
  *              Currently:
  *                  WordIo,     WordBusNumber,  WordSpace
     UINT8                   Flags,
     ACPI_PARSE_OBJECT       *MinOp,
     ACPI_PARSE_OBJECT       *MaxOp,
     ACPI_PARSE_OBJECT       *LengthOp,
-    ACPI_PARSE_OBJECT       *GranOp)
+    ACPI_PARSE_OBJECT       *GranOp,
-{
+    ACPI_PARSE_OBJECT       *Op)
+{
     if (Gbl_NoResourceChecking)
+    {
         return;
+    }
+    /*
+     * Check for a so-called "null descriptor". These are descriptors that are
+     * created with most fields set to zero. The intent is that the descriptor
+     * will be updated/completed at runtime via a BufferField.
+     *
+     * If the descriptor does NOT have a resource tag, it cannot be referenced
+     * by a BufferField and we will flag this as an error. Conversely, if
+     * the descriptor has a resource tag, we will assume that a BufferField
+     * will be used to dynamically update it, so no error.
+     *
+     * A possible enhancement to this check would be to verify that in fact
+     * a BufferField is created using the resource tag, and perhaps even
+     * verify that a Store is performed to the BufferField.
+     */
+    if (!Minimum && !Maximum && !Length && !Granularity)
+    {
+        if (!Op->Asl.ExternalName)
+        {
+            /* No resource tag. Descriptor is fixed and is also illegal */
+            AslError (ASL_ERROR, ASL_MSG_NULL_DESCRIPTOR, Op, NULL);
+        }
+        return;
+    }
     /* Basic checks on Min/Max/Length */
     if (Minimum > Maximum)

Subversion Repositories Kolibri OS

(root)/drivers/devman/acpica/compiler/aslresource.c – Rev 1498 → 2216