linux/drivers/acpi/acpica/dspkginit.c

506 lines
15 KiB
C

// SPDX-License-Identifier: BSD-3-Clause OR GPL-2.0
/******************************************************************************
*
* Module Name: dspkginit - Completion of deferred package initialization
*
* Copyright (C) 2000 - 2018, Intel Corp.
*
*****************************************************************************/
#include <acpi/acpi.h>
#include "accommon.h"
#include "acnamesp.h"
#include "amlcode.h"
#include "acdispat.h"
#include "acinterp.h"
#include "acparser.h"
#define _COMPONENT ACPI_NAMESPACE
ACPI_MODULE_NAME("dspkginit")
/* Local prototypes */
static void
acpi_ds_resolve_package_element(union acpi_operand_object **element);
/*******************************************************************************
*
* FUNCTION: acpi_ds_build_internal_package_obj
*
* PARAMETERS: walk_state - Current walk state
* op - Parser object to be translated
* element_count - Number of elements in the package - this is
* the num_elements argument to Package()
* obj_desc_ptr - Where the ACPI internal object is returned
*
* RETURN: Status
*
* DESCRIPTION: Translate a parser Op package object to the equivalent
* namespace object
*
* NOTE: The number of elements in the package will be always be the num_elements
* count, regardless of the number of elements in the package list. If
* num_elements is smaller, only that many package list elements are used.
* if num_elements is larger, the Package object is padded out with
* objects of type Uninitialized (as per ACPI spec.)
*
* Even though the ASL compilers do not allow num_elements to be smaller
* than the Package list length (for the fixed length package opcode), some
* BIOS code modifies the AML on the fly to adjust the num_elements, and
* this code compensates for that. This also provides compatibility with
* other AML interpreters.
*
******************************************************************************/
acpi_status
acpi_ds_build_internal_package_obj(struct acpi_walk_state *walk_state,
union acpi_parse_object *op,
u32 element_count,
union acpi_operand_object **obj_desc_ptr)
{
union acpi_parse_object *arg;
union acpi_parse_object *parent;
union acpi_operand_object *obj_desc = NULL;
acpi_status status = AE_OK;
u8 module_level_code = FALSE;
u16 reference_count;
u32 index;
u32 i;
ACPI_FUNCTION_TRACE(ds_build_internal_package_obj);
/* Check if we are executing module level code */
if (walk_state->parse_flags & ACPI_PARSE_MODULE_LEVEL) {
module_level_code = TRUE;
}
/* Find the parent of a possibly nested package */
parent = op->common.parent;
while ((parent->common.aml_opcode == AML_PACKAGE_OP) ||
(parent->common.aml_opcode == AML_VARIABLE_PACKAGE_OP)) {
parent = parent->common.parent;
}
/*
* If we are evaluating a Named package object of the form:
* Name (xxxx, Package)
* the package object already exists, otherwise it must be created.
*/
obj_desc = *obj_desc_ptr;
if (!obj_desc) {
obj_desc = acpi_ut_create_internal_object(ACPI_TYPE_PACKAGE);
*obj_desc_ptr = obj_desc;
if (!obj_desc) {
return_ACPI_STATUS(AE_NO_MEMORY);
}
obj_desc->package.node = parent->common.node;
}
if (obj_desc->package.flags & AOPOBJ_DATA_VALID) { /* Just in case */
return_ACPI_STATUS(AE_OK);
}
/*
* Allocate the element array (array of pointers to the individual
* objects) if necessary. the count is based on the num_elements
* parameter. Add an extra pointer slot so that the list is always
* null terminated.
*/
if (!obj_desc->package.elements) {
obj_desc->package.elements = ACPI_ALLOCATE_ZEROED(((acpi_size)
element_count
+
1) *
sizeof(void
*));
if (!obj_desc->package.elements) {
acpi_ut_delete_object_desc(obj_desc);
return_ACPI_STATUS(AE_NO_MEMORY);
}
obj_desc->package.count = element_count;
}
/* First arg is element count. Second arg begins the initializer list */
arg = op->common.value.arg;
arg = arg->common.next;
/*
* If we are executing module-level code, we will defer the
* full resolution of the package elements in order to support
* forward references from the elements. This provides
* compatibility with other ACPI implementations.
*/
if (module_level_code) {
obj_desc->package.aml_start = walk_state->aml;
obj_desc->package.aml_length = 0;
ACPI_DEBUG_PRINT_RAW((ACPI_DB_PARSE,
"%s: Deferring resolution of Package elements\n",
ACPI_GET_FUNCTION_NAME));
}
/*
* Initialize the elements of the package, up to the num_elements count.
* Package is automatically padded with uninitialized (NULL) elements
* if num_elements is greater than the package list length. Likewise,
* Package is truncated if num_elements is less than the list length.
*/
for (i = 0; arg && (i < element_count); i++) {
if (arg->common.aml_opcode == AML_INT_RETURN_VALUE_OP) {
if (arg->common.node->type == ACPI_TYPE_METHOD) {
/*
* A method reference "looks" to the parser to be a method
* invocation, so we special case it here
*/
arg->common.aml_opcode = AML_INT_NAMEPATH_OP;
status =
acpi_ds_build_internal_object(walk_state,
arg,
&obj_desc->
package.
elements[i]);
} else {
/* This package element is already built, just get it */
obj_desc->package.elements[i] =
ACPI_CAST_PTR(union acpi_operand_object,
arg->common.node);
}
} else {
status =
acpi_ds_build_internal_object(walk_state, arg,
&obj_desc->package.
elements[i]);
if (status == AE_NOT_FOUND) {
ACPI_ERROR((AE_INFO, "%-48s",
"****DS namepath not found"));
}
if (!module_level_code) {
/*
* Initialize this package element. This function handles the
* resolution of named references within the package.
* Forward references from module-level code are deferred
* until all ACPI tables are loaded.
*/
acpi_ds_init_package_element(0,
obj_desc->package.
elements[i], NULL,
&obj_desc->package.
elements[i]);
}
}
if (*obj_desc_ptr) {
/* Existing package, get existing reference count */
reference_count =
(*obj_desc_ptr)->common.reference_count;
if (reference_count > 1) {
/* Make new element ref count match original ref count */
/* TBD: Probably need an acpi_ut_add_references function */
for (index = 0;
index < ((u32)reference_count - 1);
index++) {
acpi_ut_add_reference((obj_desc->
package.
elements[i]));
}
}
}
arg = arg->common.next;
}
/* Check for match between num_elements and actual length of package_list */
if (arg) {
/*
* num_elements was exhausted, but there are remaining elements in
* the package_list. Truncate the package to num_elements.
*
* Note: technically, this is an error, from ACPI spec: "It is an
* error for NumElements to be less than the number of elements in
* the PackageList". However, we just print a message and no
* exception is returned. This provides compatibility with other
* ACPI implementations. Some firmware implementations will alter
* the num_elements on the fly, possibly creating this type of
* ill-formed package object.
*/
while (arg) {
/*
* We must delete any package elements that were created earlier
* and are not going to be used because of the package truncation.
*/
if (arg->common.node) {
acpi_ut_remove_reference(ACPI_CAST_PTR
(union
acpi_operand_object,
arg->common.node));
arg->common.node = NULL;
}
/* Find out how many elements there really are */
i++;
arg = arg->common.next;
}
ACPI_INFO(("Actual Package length (%u) is larger than "
"NumElements field (%u), truncated",
i, element_count));
} else if (i < element_count) {
/*
* Arg list (elements) was exhausted, but we did not reach
* num_elements count.
*
* Note: this is not an error, the package is padded out
* with NULLs as per the ACPI specification.
*/
ACPI_DEBUG_PRINT_RAW((ACPI_DB_INFO,
"%s: Package List length (%u) smaller than NumElements "
"count (%u), padded with null elements\n",
ACPI_GET_FUNCTION_NAME, i,
element_count));
}
/* Module-level packages will be resolved later */
if (!module_level_code) {
obj_desc->package.flags |= AOPOBJ_DATA_VALID;
}
op->common.node = ACPI_CAST_PTR(struct acpi_namespace_node, obj_desc);
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ds_init_package_element
*
* PARAMETERS: acpi_pkg_callback
*
* RETURN: Status
*
* DESCRIPTION: Resolve a named reference element within a package object
*
******************************************************************************/
acpi_status
acpi_ds_init_package_element(u8 object_type,
union acpi_operand_object *source_object,
union acpi_generic_state *state, void *context)
{
union acpi_operand_object **element_ptr;
ACPI_FUNCTION_TRACE(ds_init_package_element);
if (!source_object) {
return_ACPI_STATUS(AE_OK);
}
/*
* The following code is a bit of a hack to workaround a (current)
* limitation of the acpi_pkg_callback interface. We need a pointer
* to the location within the element array because a new object
* may be created and stored there.
*/
if (context) {
/* A direct call was made to this function */
element_ptr = (union acpi_operand_object **)context;
} else {
/* Call came from acpi_ut_walk_package_tree */
element_ptr = state->pkg.this_target_obj;
}
/* We are only interested in reference objects/elements */
if (source_object->common.type == ACPI_TYPE_LOCAL_REFERENCE) {
/* Attempt to resolve the (named) reference to a namespace node */
acpi_ds_resolve_package_element(element_ptr);
} else if (source_object->common.type == ACPI_TYPE_PACKAGE) {
source_object->package.flags |= AOPOBJ_DATA_VALID;
}
return_ACPI_STATUS(AE_OK);
}
/*******************************************************************************
*
* FUNCTION: acpi_ds_resolve_package_element
*
* PARAMETERS: element_ptr - Pointer to a reference object
*
* RETURN: Possible new element is stored to the indirect element_ptr
*
* DESCRIPTION: Resolve a package element that is a reference to a named
* object.
*
******************************************************************************/
static void
acpi_ds_resolve_package_element(union acpi_operand_object **element_ptr)
{
acpi_status status;
acpi_status status2;
union acpi_generic_state scope_info;
union acpi_operand_object *element = *element_ptr;
struct acpi_namespace_node *resolved_node;
struct acpi_namespace_node *original_node;
char *external_path = "";
acpi_object_type type;
ACPI_FUNCTION_TRACE(ds_resolve_package_element);
/* Check if reference element is already resolved */
if (element->reference.resolved) {
ACPI_DEBUG_PRINT_RAW((ACPI_DB_PARSE,
"%s: Package element is already resolved\n",
ACPI_GET_FUNCTION_NAME));
return_VOID;
}
/* Element must be a reference object of correct type */
scope_info.scope.node = element->reference.node; /* Prefix node */
status = acpi_ns_lookup(&scope_info, (char *)element->reference.aml,
ACPI_TYPE_ANY, ACPI_IMODE_EXECUTE,
ACPI_NS_SEARCH_PARENT | ACPI_NS_DONT_OPEN_SCOPE,
NULL, &resolved_node);
if (ACPI_FAILURE(status)) {
if ((status == AE_NOT_FOUND)
&& acpi_gbl_ignore_package_resolution_errors) {
/*
* Optionally be silent about the NOT_FOUND case for the referenced
* name. Although this is potentially a serious problem,
* it can generate a lot of noise/errors on platforms whose
* firmware carries around a bunch of unused Package objects.
* To disable these errors, set this global to TRUE:
* acpi_gbl_ignore_package_resolution_errors
*
* If the AML actually tries to use such a package, the unresolved
* element(s) will be replaced with NULL elements.
*/
/* Referenced name not found, set the element to NULL */
acpi_ut_remove_reference(*element_ptr);
*element_ptr = NULL;
return_VOID;
}
status2 = acpi_ns_externalize_name(ACPI_UINT32_MAX,
(char *)element->reference.
aml, NULL, &external_path);
ACPI_EXCEPTION((AE_INFO, status,
"While resolving a named reference package element - %s",
external_path));
if (ACPI_SUCCESS(status2)) {
ACPI_FREE(external_path);
}
/* Could not resolve name, set the element to NULL */
acpi_ut_remove_reference(*element_ptr);
*element_ptr = NULL;
return_VOID;
} else if (resolved_node->type == ACPI_TYPE_ANY) {
/* Named reference not resolved, return a NULL package element */
ACPI_ERROR((AE_INFO,
"Could not resolve named package element [%4.4s] in [%4.4s]",
resolved_node->name.ascii,
scope_info.scope.node->name.ascii));
*element_ptr = NULL;
return_VOID;
}
/*
* Special handling for Alias objects. We need resolved_node to point
* to the Alias target. This effectively "resolves" the alias.
*/
if (resolved_node->type == ACPI_TYPE_LOCAL_ALIAS) {
resolved_node = ACPI_CAST_PTR(struct acpi_namespace_node,
resolved_node->object);
}
/* Update the reference object */
element->reference.resolved = TRUE;
element->reference.node = resolved_node;
type = element->reference.node->type;
/*
* Attempt to resolve the node to a value before we insert it into
* the package. If this is a reference to a common data type,
* resolve it immediately. According to the ACPI spec, package
* elements can only be "data objects" or method references.
* Attempt to resolve to an Integer, Buffer, String or Package.
* If cannot, return the named reference (for things like Devices,
* Methods, etc.) Buffer Fields and Fields will resolve to simple
* objects (int/buf/str/pkg).
*
* NOTE: References to things like Devices, Methods, Mutexes, etc.
* will remain as named references. This behavior is not described
* in the ACPI spec, but it appears to be an oversight.
*/
original_node = resolved_node;
status = acpi_ex_resolve_node_to_value(&resolved_node, NULL);
if (ACPI_FAILURE(status)) {
return_VOID;
}
switch (type) {
/*
* These object types are a result of named references, so we will
* leave them as reference objects. In other words, these types
* have no intrinsic "value".
*/
case ACPI_TYPE_DEVICE:
case ACPI_TYPE_THERMAL:
case ACPI_TYPE_METHOD:
break;
case ACPI_TYPE_MUTEX:
case ACPI_TYPE_POWER:
case ACPI_TYPE_PROCESSOR:
case ACPI_TYPE_EVENT:
case ACPI_TYPE_REGION:
/* acpi_ex_resolve_node_to_value gave these an extra reference */
acpi_ut_remove_reference(original_node->object);
break;
default:
/*
* For all other types - the node was resolved to an actual
* operand object with a value, return the object. Remove
* a reference on the existing object.
*/
acpi_ut_remove_reference(element);
*element_ptr = (union acpi_operand_object *)resolved_node;
break;
}
return_VOID;
}