linux/drivers/acpi/acpica/utxfinit.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

309 lines
9.5 KiB
C

/******************************************************************************
*
* Module Name: utxfinit - External interfaces for ACPICA initialization
*
*****************************************************************************/
/*
* 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.
*/
#define EXPORT_ACPI_INTERFACES
#include <acpi/acpi.h>
#include "accommon.h"
#include "acevents.h"
#include "acnamesp.h"
#include "acdebug.h"
#include "actables.h"
#define _COMPONENT ACPI_UTILITIES
ACPI_MODULE_NAME("utxfinit")
/* For acpi_exec only */
void ae_do_object_overrides(void);
/*******************************************************************************
*
* FUNCTION: acpi_initialize_subsystem
*
* PARAMETERS: None
*
* RETURN: Status
*
* DESCRIPTION: Initializes all global variables. This is the first function
* called, so any early initialization belongs here.
*
******************************************************************************/
acpi_status ACPI_INIT_FUNCTION acpi_initialize_subsystem(void)
{
acpi_status status;
ACPI_FUNCTION_TRACE(acpi_initialize_subsystem);
acpi_gbl_startup_flags = ACPI_SUBSYSTEM_INITIALIZE;
ACPI_DEBUG_EXEC(acpi_ut_init_stack_ptr_trace());
/* Initialize the OS-Dependent layer */
status = acpi_os_initialize();
if (ACPI_FAILURE(status)) {
ACPI_EXCEPTION((AE_INFO, status, "During OSL initialization"));
return_ACPI_STATUS(status);
}
/* Initialize all globals used by the subsystem */
status = acpi_ut_init_globals();
if (ACPI_FAILURE(status)) {
ACPI_EXCEPTION((AE_INFO, status,
"During initialization of globals"));
return_ACPI_STATUS(status);
}
/* Create the default mutex objects */
status = acpi_ut_mutex_initialize();
if (ACPI_FAILURE(status)) {
ACPI_EXCEPTION((AE_INFO, status,
"During Global Mutex creation"));
return_ACPI_STATUS(status);
}
/*
* Initialize the namespace manager and
* the root of the namespace tree
*/
status = acpi_ns_root_initialize();
if (ACPI_FAILURE(status)) {
ACPI_EXCEPTION((AE_INFO, status,
"During Namespace initialization"));
return_ACPI_STATUS(status);
}
/* Initialize the global OSI interfaces list with the static names */
status = acpi_ut_initialize_interfaces();
if (ACPI_FAILURE(status)) {
ACPI_EXCEPTION((AE_INFO, status,
"During OSI interfaces initialization"));
return_ACPI_STATUS(status);
}
return_ACPI_STATUS(AE_OK);
}
ACPI_EXPORT_SYMBOL_INIT(acpi_initialize_subsystem)
/*******************************************************************************
*
* FUNCTION: acpi_enable_subsystem
*
* PARAMETERS: flags - Init/enable Options
*
* RETURN: Status
*
* DESCRIPTION: Completes the subsystem initialization including hardware.
* Puts system into ACPI mode if it isn't already.
*
******************************************************************************/
acpi_status ACPI_INIT_FUNCTION acpi_enable_subsystem(u32 flags)
{
acpi_status status = AE_OK;
ACPI_FUNCTION_TRACE(acpi_enable_subsystem);
/*
* The early initialization phase is complete. The namespace is loaded,
* and we can now support address spaces other than Memory, I/O, and
* PCI_Config.
*/
acpi_gbl_early_initialization = FALSE;
#if (!ACPI_REDUCED_HARDWARE)
/* Enable ACPI mode */
if (!(flags & ACPI_NO_ACPI_ENABLE)) {
ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
"[Init] Going into ACPI mode\n"));
acpi_gbl_original_mode = acpi_hw_get_mode();
status = acpi_enable();
if (ACPI_FAILURE(status)) {
ACPI_WARNING((AE_INFO, "AcpiEnable failed"));
return_ACPI_STATUS(status);
}
}
/*
* Obtain a permanent mapping for the FACS. This is required for the
* Global Lock and the Firmware Waking Vector
*/
if (!(flags & ACPI_NO_FACS_INIT)) {
status = acpi_tb_initialize_facs();
if (ACPI_FAILURE(status)) {
ACPI_WARNING((AE_INFO, "Could not map the FACS table"));
return_ACPI_STATUS(status);
}
}
/*
* Initialize ACPI Event handling (Fixed and General Purpose)
*
* Note1: We must have the hardware and events initialized before we can
* execute any control methods safely. Any control method can require
* ACPI hardware support, so the hardware must be fully initialized before
* any method execution!
*
* Note2: Fixed events are initialized and enabled here. GPEs are
* initialized, but cannot be enabled until after the hardware is
* completely initialized (SCI and global_lock activated) and the various
* initialization control methods are run (_REG, _STA, _INI) on the
* entire namespace.
*/
if (!(flags & ACPI_NO_EVENT_INIT)) {
ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
"[Init] Initializing ACPI events\n"));
status = acpi_ev_initialize_events();
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
}
/*
* Install the SCI handler and Global Lock handler. This completes the
* hardware initialization.
*/
if (!(flags & ACPI_NO_HANDLER_INIT)) {
ACPI_DEBUG_PRINT((ACPI_DB_EXEC,
"[Init] Installing SCI/GL handlers\n"));
status = acpi_ev_install_xrupt_handlers();
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
}
#endif /* !ACPI_REDUCED_HARDWARE */
return_ACPI_STATUS(status);
}
ACPI_EXPORT_SYMBOL_INIT(acpi_enable_subsystem)
/*******************************************************************************
*
* FUNCTION: acpi_initialize_objects
*
* PARAMETERS: flags - Init/enable Options
*
* RETURN: Status
*
* DESCRIPTION: Completes namespace initialization by initializing device
* objects and executing AML code for Regions, buffers, etc.
*
******************************************************************************/
acpi_status ACPI_INIT_FUNCTION acpi_initialize_objects(u32 flags)
{
acpi_status status = AE_OK;
ACPI_FUNCTION_TRACE(acpi_initialize_objects);
#ifdef ACPI_EXEC_APP
/*
* This call implements the "initialization file" option for acpi_exec.
* This is the precise point that we want to perform the overrides.
*/
ae_do_object_overrides();
#endif
/*
* Execute any module-level code that was detected during the table load
* phase. Although illegal since ACPI 2.0, there are many machines that
* contain this type of code. Each block of detected executable AML code
* outside of any control method is wrapped with a temporary control
* method object and placed on a global list. The methods on this list
* are executed below.
*
* This case executes the module-level code for all tables only after
* all of the tables have been loaded. It is a legacy option and is
* not compatible with other ACPI implementations. See acpi_ns_load_table.
*/
if (!acpi_gbl_parse_table_as_term_list
&& acpi_gbl_group_module_level_code) {
acpi_ns_exec_module_code_list();
/*
* Initialize the objects that remain uninitialized. This
* runs the executable AML that may be part of the
* declaration of these objects:
* operation_regions, buffer_fields, Buffers, and Packages.
*/
if (!(flags & ACPI_NO_OBJECT_INIT)) {
status = acpi_ns_initialize_objects();
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
}
}
/*
* Initialize all device/region objects in the namespace. This runs
* the device _STA and _INI methods and region _REG methods.
*/
if (!(flags & (ACPI_NO_DEVICE_INIT | ACPI_NO_ADDRESS_SPACE_INIT))) {
status = acpi_ns_initialize_devices(flags);
if (ACPI_FAILURE(status)) {
return_ACPI_STATUS(status);
}
}
/*
* Empty the caches (delete the cached objects) on the assumption that
* the table load filled them up more than they will be at runtime --
* thus wasting non-paged memory.
*/
status = acpi_purge_cached_objects();
acpi_gbl_startup_flags |= ACPI_INITIALIZED_OK;
return_ACPI_STATUS(status);
}
ACPI_EXPORT_SYMBOL_INIT(acpi_initialize_objects)