linux/drivers/acpi/acpica/psxface.c
Lv Zheng de56ba95e8 ACPICA: Interpreter: Fix MLC issues by switching to new term_list grammar for table loading
ACPICA commit 0e24fb67cde08d7df7671d7d7b183490dc79707e

The MLC (Module Level Code) is an ACPICA terminology describing the AML
code out of any control method, its support is an indication of the
interpreter behavior during the table loading.

The original implementation of MLC in ACPICA had several issues:
1. Out of any control method, besides of the object creating opcodes, only
   the code blocks wrapped by "If/Else/While" opcodes were supported.
2. The supported MLC code blocks were executed after loading the table
   rather than being executed right in place.
   ============================================================
   The demo of this order issue is as follows:
     Name (OBJ1, 1)
     If (CND1 == 1)
     {
       Name (OBJ2, 2)
     }
     Name (OBJ3, 3)
   The original MLC support created OBJ2 after OBJ3's creation.
   ============================================================
Other than these limitations, MLC support in ACPICA looks correct. And
supporting this should be easy/natural for ACPICA, but enabling of this was
blocked by some ACPICA internal and OSPM specific initialization order
issues we've fixed recently. The wrong support started from the following
false bug fixing commit:
  Commit: 7f0c826a43
  Subject: ACPICA: Add support for module-level executable AML code
  Commit: 9a884ab64a
  Subject: ACPICA: Add additional module-level code support
  ...

We can confirm Windows interpreter behavior via reverse engineering means.
It can be proven that not only If/Else/While wrapped code blocks, all
opcodes can be executed at the module level, including operation region
accesses. And it can be proven that the MLC should be executed right in
place, not in such a deferred way executed after loading the table.

And the above facts indeed reflect the spec words around ACPI definition
block tables (DSDT/SSDT/...), the entire table and the Scope object is
defined by the AML specification in BNF style as:
  AMLCode := def_block_header term_list
  def_scope := scope_op pkg_length name_string term_list
The bodies of the scope opening terms (AMLCode/Scope) are all term_list,
thus the table loading should be no difference than the control method
evaluations as the body of the Method is also defined by the AML
specification as term_list:
  def_method := method_op pkg_length name_string method_flags term_list
The only difference is: after evaluating control method, created named
objects may be freed due to no reference, while named objects created by
the table loading should only be freed after unloading the table.

So this patch follows the spec and the de-facto standard behavior, enables
the new grammar (term_list) for the table loading.

By doing so, beyond the fixes to the above issues, we can see additional
differences comparing to the old grammar based table loading:
1. Originally, beyond the scope opening terms (AMLCode/Scope),
   If/Else/While wrapped code blocks under the scope creating terms
   (Device/power_resource/Processor/thermal_zone) are also supported as
   deferred MLC, which violates the spec defined grammar where object_list
   is enforced. With MLC support improved as non-deferred, the interpreter
   parses such scope creating terms as term_list rather object_list like the
   scope opening terms.
   After probing the Windows behavior and proving that it also parses these
   terms as term_list, we submitted an ECR (Engineering Change Request) to
   the ASWG (ACPI Specification Working Group) to clarify this. The ECR is
   titled as "ASL Grammar Clarification for Executable AML Opcodes" and has
   been accepted by the ASWG. The new grammar will appear in ACPI
   specification 6.2.
2. Originally, Buffer/Package/operation_region/create_XXXField/bank_field
   arguments are evaluated in a deferred way after loading the table. With
   MLC support improved, they are also parsed right in place during the
   table loading.
   This is also Windows compliant and the only difference is the removal
   of the debugging messages implemented before acpi_ds_execute_arguments(),
   see Link # [1] for the details. A previous commit should have ensured
   that acpi_check_address_range() won't regress.

Note that enabling this feature may cause regressions due to long term
Linux ACPI support on top of the wrong grammar. So this patch also prepares
a global option to be used to roll back to the old grammar during the
period between a regression is reported and the regression is
root-cause-fixed. Lv Zheng.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=112911 # [1]
Link: https://bugzilla.kernel.org/show_bug.cgi?id=117671 # [1]
Link: https://bugzilla.kernel.org/show_bug.cgi?id=153541 # [1]
Link: https://github.com/acpica/acpica/issues/122
Link: https://bugs.acpica.org/show_bug.cgi?id=963
Link: https://github.com/acpica/acpica/commit/0e24fb67
Reported-and-tested-by: Chris Bainbridge <chris.bainbridge@gmail.com>
Reported-by: Ehsan <dashesy@gmail.com>
Reported-and-tested-by: Dutch Guy <lucht_piloot@gmx.net>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2016-09-10 02:43:02 +02:00

357 lines
10 KiB
C

/******************************************************************************
*
* Module Name: psxface - Parser external interfaces
*
*****************************************************************************/
/*
* Copyright (C) 2000 - 2016, Intel Corp.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions, and the following disclaimer,
* without modification.
* 2. Redistributions in binary form must reproduce at minimum a disclaimer
* substantially similar to the "NO WARRANTY" disclaimer below
* ("Disclaimer") and any redistribution must be conditioned upon
* including a substantially similar Disclaimer requirement for further
* binary redistribution.
* 3. Neither the names of the above-listed copyright holders nor the names
* of any contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* Alternatively, this software may be distributed under the terms of the
* GNU General Public License ("GPL") version 2 as published by the Free
* Software Foundation.
*
* NO WARRANTY
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
* IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGES.
*/
#include <acpi/acpi.h>
#include "accommon.h"
#include "acparser.h"
#include "acdispat.h"
#include "acinterp.h"
#include "actables.h"
#include "acnamesp.h"
#define _COMPONENT ACPI_PARSER
ACPI_MODULE_NAME("psxface")
/* Local Prototypes */
static void
acpi_ps_update_parameter_list(struct acpi_evaluate_info *info, u16 action);
/*******************************************************************************
*
* FUNCTION: acpi_debug_trace
*
* PARAMETERS: method_name - Valid ACPI name string
* debug_level - Optional level mask. 0 to use default
* debug_layer - Optional layer mask. 0 to use default
* flags - bit 1: one shot(1) or persistent(0)
*
* RETURN: Status
*
* DESCRIPTION: External interface to enable debug tracing during control
* method execution
*
******************************************************************************/
acpi_status
acpi_debug_trace(const char *name, u32 debug_level, u32 debug_layer, u32 flags)
{
acpi_status status;
status = acpi_ut_acquire_mutex(ACPI_MTX_NAMESPACE);
if (ACPI_FAILURE(status)) {
return (status);
}
acpi_gbl_trace_method_name = name;
acpi_gbl_trace_flags = flags;
acpi_gbl_trace_dbg_level = debug_level;
acpi_gbl_trace_dbg_layer = debug_layer;
status = AE_OK;
(void)acpi_ut_release_mutex(ACPI_MTX_NAMESPACE);
return (status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ps_execute_method
*
* PARAMETERS: info - Method info block, contains:
* node - Method Node to execute
* obj_desc - Method object
* parameters - List of parameters to pass to the method,
* terminated by NULL. Params itself may be
* NULL if no parameters are being passed.
* return_object - Where to put method's return value (if
* any). If NULL, no value is returned.
* parameter_type - Type of Parameter list
* return_object - Where to put method's return value (if
* any). If NULL, no value is returned.
* pass_number - Parse or execute pass
*
* RETURN: Status
*
* DESCRIPTION: Execute a control method
*
******************************************************************************/
acpi_status acpi_ps_execute_method(struct acpi_evaluate_info *info)
{
acpi_status status;
union acpi_parse_object *op;
struct acpi_walk_state *walk_state;
ACPI_FUNCTION_TRACE(ps_execute_method);
/* Quick validation of DSDT header */
acpi_tb_check_dsdt_header();
/* Validate the Info and method Node */
if (!info || !info->node) {
return_ACPI_STATUS(AE_NULL_ENTRY);
}
/* Init for new method, wait on concurrency semaphore */
status =
acpi_ds_begin_method_execution(info->node, info->obj_desc, NULL);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/*
* The caller "owns" the parameters, so give each one an extra reference
*/
acpi_ps_update_parameter_list(info, REF_INCREMENT);
/*
* Execute the method. Performs parse simultaneously
*/
ACPI_DEBUG_PRINT((ACPI_DB_PARSE,
"**** Begin Method Parse/Execute [%4.4s] **** Node=%p Obj=%p\n",
info->node->name.ascii, info->node, info->obj_desc));
/* Create and init a Root Node */
op = acpi_ps_create_scope_op(info->obj_desc->method.aml_start);
if (!op) {
status = AE_NO_MEMORY;
goto cleanup;
}
/* Create and initialize a new walk state */
info->pass_number = ACPI_IMODE_EXECUTE;
walk_state =
acpi_ds_create_walk_state(info->obj_desc->method.owner_id, NULL,
NULL, NULL);
if (!walk_state) {
status = AE_NO_MEMORY;
goto cleanup;
}
status = acpi_ds_init_aml_walk(walk_state, op, info->node,
info->obj_desc->method.aml_start,
info->obj_desc->method.aml_length, info,
info->pass_number);
if (ACPI_FAILURE(status)) {
acpi_ds_delete_walk_state(walk_state);
goto cleanup;
}
if (info->obj_desc->method.info_flags & ACPI_METHOD_MODULE_LEVEL) {
walk_state->parse_flags |= ACPI_PARSE_MODULE_LEVEL;
}
/* Invoke an internal method if necessary */
if (info->obj_desc->method.info_flags & ACPI_METHOD_INTERNAL_ONLY) {
status =
info->obj_desc->method.dispatch.implementation(walk_state);
info->return_object = walk_state->return_desc;
/* Cleanup states */
acpi_ds_scope_stack_clear(walk_state);
acpi_ps_cleanup_scope(&walk_state->parser_state);
acpi_ds_terminate_control_method(walk_state->method_desc,
walk_state);
acpi_ds_delete_walk_state(walk_state);
goto cleanup;
}
/*
* Start method evaluation with an implicit return of zero.
* This is done for Windows compatibility.
*/
if (acpi_gbl_enable_interpreter_slack) {
walk_state->implicit_return_obj =
acpi_ut_create_integer_object((u64) 0);
if (!walk_state->implicit_return_obj) {
status = AE_NO_MEMORY;
acpi_ds_delete_walk_state(walk_state);
goto cleanup;
}
}
/* Parse the AML */
status = acpi_ps_parse_aml(walk_state);
/* walk_state was deleted by parse_aml */
cleanup:
acpi_ps_delete_parse_tree(op);
/* Take away the extra reference that we gave the parameters above */
acpi_ps_update_parameter_list(info, REF_DECREMENT);
/* Exit now if error above */
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
/*
* If the method has returned an object, signal this to the caller with
* a control exception code
*/
if (info->return_object) {
ACPI_DEBUG_PRINT((ACPI_DB_PARSE, "Method returned ObjDesc=%p\n",
info->return_object));
ACPI_DUMP_STACK_ENTRY(info->return_object);
status = AE_CTRL_RETURN_VALUE;
}
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ps_execute_table
*
* PARAMETERS: info - Method info block, contains:
* node - Node to where the is entered into the
* namespace
* obj_desc - Pseudo method object describing the AML
* code of the entire table
* pass_number - Parse or execute pass
*
* RETURN: Status
*
* DESCRIPTION: Execute a table
*
******************************************************************************/
acpi_status acpi_ps_execute_table(struct acpi_evaluate_info *info)
{
acpi_status status;
union acpi_parse_object *op = NULL;
struct acpi_walk_state *walk_state = NULL;
ACPI_FUNCTION_TRACE(ps_execute_table);
/* Create and init a Root Node */
op = acpi_ps_create_scope_op(info->obj_desc->method.aml_start);
if (!op) {
status = AE_NO_MEMORY;
goto cleanup;
}
/* Create and initialize a new walk state */
walk_state =
acpi_ds_create_walk_state(info->obj_desc->method.owner_id, NULL,
NULL, NULL);
if (!walk_state) {
status = AE_NO_MEMORY;
goto cleanup;
}
status = acpi_ds_init_aml_walk(walk_state, op, info->node,
info->obj_desc->method.aml_start,
info->obj_desc->method.aml_length, info,
info->pass_number);
if (ACPI_FAILURE(status)) {
goto cleanup;
}
if (info->obj_desc->method.info_flags & ACPI_METHOD_MODULE_LEVEL) {
walk_state->parse_flags |= ACPI_PARSE_MODULE_LEVEL;
}
/*
* Parse the AML, walk_state will be deleted by parse_aml
*/
status = acpi_ps_parse_aml(walk_state);
walk_state = NULL;
cleanup:
if (walk_state) {
acpi_ds_delete_walk_state(walk_state);
}
if (op) {
acpi_ps_delete_parse_tree(op);
}
return_ACPI_STATUS(status);
}
/*******************************************************************************
*
* FUNCTION: acpi_ps_update_parameter_list
*
* PARAMETERS: info - See struct acpi_evaluate_info
* (Used: parameter_type and Parameters)
* action - Add or Remove reference
*
* RETURN: Status
*
* DESCRIPTION: Update reference count on all method parameter objects
*
******************************************************************************/
static void
acpi_ps_update_parameter_list(struct acpi_evaluate_info *info, u16 action)
{
u32 i;
if (info->parameters) {
/* Update reference count for each parameter */
for (i = 0; info->parameters[i]; i++) {
/* Ignore errors, just do them all */
(void)acpi_ut_update_object_reference(info->
parameters[i],
action);
}
}
}