ACPICA: Add support for module-level executable AML code

Add limited support for executable AML code that exists outside
of any control method. This type of code has been illegal since
ACPI 2.0.  The code must exist in an If/Else/While block. All AML
tables are supported, including tables that are dynamically loaded.
ACPICA BZ 762.

http://acpica.org/bugzilla/show_bug.cgi?id=762

Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>

1 files changed, 137 insertions, 0 deletions

diff --git a/drivers/acpi/acpica/nseval.c b/drivers/acpi/acpica/nseval.c
index 8e7dec1176c9..846d1132feb1 100644
--- a/drivers/acpi/acpica/nseval.c
+++ b/drivers/acpi/acpica/nseval.c
@@ -50,6 +50,11 @@
 #define _COMPONENT          ACPI_NAMESPACE
 ACPI_MODULE_NAME("nseval")
 
+/* Local prototypes */
+static void
+acpi_ns_exec_module_code(union acpi_operand_object *method_obj,
+                         struct acpi_evaluate_info *info);
+
 /*******************************************************************************
  *
  * FUNCTION:    acpi_ns_evaluate
@@ -76,6 +81,7 @@ ACPI_MODULE_NAME("nseval")
  * MUTEX:       Locks interpreter
  *
  ******************************************************************************/
+
 acpi_status acpi_ns_evaluate(struct acpi_evaluate_info * info)
 {
         acpi_status status;
@@ -276,3 +282,134 @@ acpi_status acpi_ns_evaluate(struct acpi_evaluate_info * info)
          */
         return_ACPI_STATUS(status);
 }
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ns_exec_module_code_list
+ *
+ * PARAMETERS:  None
+ *
+ * RETURN:      None. Exceptions during method execution are ignored, since
+ *              we cannot abort a table load.
+ *
+ * DESCRIPTION: Execute all elements of the global module-level code list.
+ *              Each element is executed as a single control method.
+ *
+ ******************************************************************************/
+
+void acpi_ns_exec_module_code_list(void)
+{
+        union acpi_operand_object *prev;
+        union acpi_operand_object *next;
+        struct acpi_evaluate_info *info;
+        u32 method_count = 0;
+
+        ACPI_FUNCTION_TRACE(ns_exec_module_code_list);
+
+        /* Exit now if the list is empty */
+
+        next = acpi_gbl_module_code_list;
+        if (!next) {
+                return_VOID;
+        }
+
+        /* Allocate the evaluation information block */
+
+        info = ACPI_ALLOCATE(sizeof(struct acpi_evaluate_info));
+        if (!info) {
+                return_VOID;
+        }
+
+        /* Walk the list, executing each "method" */
+
+        while (next) {
+                prev = next;
+                next = next->method.mutex;
+
+                /* Clear the link field and execute the method */
+
+                prev->method.mutex = NULL;
+                acpi_ns_exec_module_code(prev, info);
+                method_count++;
+
+                /* Delete the (temporary) method object */
+
+                acpi_ut_remove_reference(prev);
+        }
+
+        ACPI_INFO((AE_INFO,
+                   "Executed %u blocks of module-level executable AML code",
+                   method_count));
+
+        ACPI_FREE(info);
+        acpi_gbl_module_code_list = NULL;
+        return_VOID;
+}
+
+/*******************************************************************************
+ *
+ * FUNCTION:    acpi_ns_exec_module_code
+ *
+ * PARAMETERS:  method_obj          - Object container for the module-level code
+ *              Info                - Info block for method evaluation
+ *
+ * RETURN:      None. Exceptions during method execution are ignored, since
+ *              we cannot abort a table load.
+ *
+ * DESCRIPTION: Execute a control method containing a block of module-level
+ *              executable AML code. The control method is temporarily
+ *              installed to the root node, then evaluated.
+ *
+ ******************************************************************************/
+
+static void
+acpi_ns_exec_module_code(union acpi_operand_object *method_obj,
+                         struct acpi_evaluate_info *info)
+{
+        union acpi_operand_object *root_obj;
+        acpi_status status;
+
+        ACPI_FUNCTION_TRACE(ns_exec_module_code);
+
+        /* Initialize the evaluation information block */
+
+        ACPI_MEMSET(info, 0, sizeof(struct acpi_evaluate_info));
+        info->prefix_node = acpi_gbl_root_node;
+
+        /*
+         * Get the currently attached root object. Add a reference, because the
+         * ref count will be decreased when the method object is installed to
+         * the root node.
+         */
+        root_obj = acpi_ns_get_attached_object(acpi_gbl_root_node);
+        acpi_ut_add_reference(root_obj);
+
+        /* Install the method (module-level code) in the root node */
+
+        status = acpi_ns_attach_object(acpi_gbl_root_node, method_obj,
+                                       ACPI_TYPE_METHOD);
+        if (ACPI_FAILURE(status)) {
+                goto exit;
+        }
+
+        /* Execute the root node as a control method */
+
+        status = acpi_ns_evaluate(info);
+
+        ACPI_DEBUG_PRINT((ACPI_DB_INIT, "Executed module-level code at %p\n",
+                          method_obj->method.aml_start));
+
+        /* Detach the temporary method object */
+
+        acpi_ns_detach_object(acpi_gbl_root_node);
+
+        /* Restore the original root object */
+
+        status =
+            acpi_ns_attach_object(acpi_gbl_root_node, root_obj,
+                                  ACPI_TYPE_DEVICE);
+
+      exit:
+        acpi_ut_remove_reference(root_obj);
+        return_VOID;
+}