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authorLinus Torvalds <torvalds@linux-foundation.org>2024-03-13 19:54:05 +0100
committerLinus Torvalds <torvalds@linux-foundation.org>2024-03-13 19:54:05 +0100
commit943446795909929f261565cebafb3b56d66cc513 (patch)
tree6bcee5060ad8a6e025a090a3c34aa0b635c1783d /Documentation/firmware-guide
parentMerge tag 'pm-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafae... (diff)
parentMerge branches 'acpi-x86', 'acpi-video', 'acpi-apei' and 'acpi-misc' (diff)
downloadlinux-943446795909929f261565cebafb3b56d66cc513.tar.xz
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Merge tag 'acpi-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull ACPI updates from Rafael Wysocki: "These modify the ACPI device events and processor enumeration code to take the 'enabled' _STA bit into account as mandated by the ACPI specification, convert several platform drivers to using a remove callback that returns void, add some new quirks for ACPI IRQ override and other things, address assorted issues and clean up code. Specifics: - Rearrange Device Check and Bus Check notification handling in the ACPI device hotplug code to make it get the "enabled" _STA bit into account (Rafael Wysocki) - Modify acpi_processor_add() to skip processors with the "enabled" _STA bit clear, as per the specification (Rafael Wysocki) - Stop failing Device Check notification handling without a valid reason (Rafael Wysocki) - Defer enumeration of devices that depend on a device with an ACPI device ID equalt to INTC10CF to address probe ordering issues on some platforms (Wentong Wu) - Constify acpi_bus_type (Ricardo Marliere) - Make the ACPI-specific suspend-to-idle code take the Low-Power S0 Idle MSFT UUID into account on non-AMD systems (Rafael Wysocki) - Add ACPI IRQ override quirks for some new platforms (Sergey Kalinichev, Maxim Kudinov, Alexey Froloff, Sviatoslav Harasymchuk, Nicolas Haye) - Make the NFIT parsing code use acpi_evaluate_dsm_typed() (Andy Shevchenko) - Fix a memory leak in acpi_processor_power_exit() (Armin Wolf) - Make it possible to quirk the CSI-2 and MIPI DisCo for Imaging properties parsing and add a quirk for Dell XPS 9315 (Sakari Ailus) - Prevent false-positive static checker warnings from triggering by intializing some variables in the ACPI thermal code to zero (Colin Ian King) - Add DELL0501 handling to acpi_quirk_skip_serdev_enumeration() and make that function generic (Hans de Goede) - Make the ACPI backlight code handle fetching EDID that is longer than 256 bytes (Mario Limonciello) - Skip initialization of GHES_ASSIST structures for Machine Check Architecture in APEI (Avadhut Naik) - Convert several plaform drivers in the ACPI subsystem to using a remove callback that returns void (Uwe Kleine-König) - Drop the long-deprecated custom_method debugfs interface that is problematic from the security standpoint (Rafael Wysocki) - Use %pe in a couple of places in the ACPI code for easier error decoding (Onkarnath) - Fix register width information handling during system memory accesses in the ACPI CPPC library (Jarred White) - Add AMD CPPC V2 support for family 17h processors to the ACPI CPPC library (Perry Yuan)" * tag 'acpi-6.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (35 commits) ACPI: resource: Use IRQ override on Maibenben X565 ACPI: CPPC: Use access_width over bit_width for system memory accesses ACPI: CPPC: enable AMD CPPC V2 support for family 17h processors ACPI: APEI: Skip initialization of GHES_ASSIST structures for Machine Check Architecture ACPI: scan: Consolidate Device Check and Bus Check notification handling ACPI: scan: Rework Device Check and Bus Check notification handling ACPI: scan: Make acpi_processor_add() check the device enabled bit ACPI: scan: Relocate acpi_bus_trim_one() ACPI: scan: Fix device check notification handling ACPI: resource: Add MAIBENBEN X577 to irq1_edge_low_force_override ACPI: pfr_update: Convert to platform remove callback returning void ACPI: pfr_telemetry: Convert to platform remove callback returning void ACPI: fan: Convert to platform remove callback returning void ACPI: GED: Convert to platform remove callback returning void ACPI: DPTF: Convert to platform remove callback returning void ACPI: AGDI: Convert to platform remove callback returning void ACPI: TAD: Convert to platform remove callback returning void ACPI: APEI: GHES: Convert to platform remove callback returning void ACPI: property: Polish ignoring bad data nodes ACPI: thermal_lib: Initialize temp_decik to zero ...
Diffstat (limited to 'Documentation/firmware-guide')
-rw-r--r--Documentation/firmware-guide/acpi/index.rst1
-rw-r--r--Documentation/firmware-guide/acpi/method-customizing.rst89
2 files changed, 0 insertions, 90 deletions
diff --git a/Documentation/firmware-guide/acpi/index.rst b/Documentation/firmware-guide/acpi/index.rst
index b6a42f4ffe03..b246902f523f 100644
--- a/Documentation/firmware-guide/acpi/index.rst
+++ b/Documentation/firmware-guide/acpi/index.rst
@@ -14,7 +14,6 @@ ACPI Support
dsd/phy
enumeration
osi
- method-customizing
method-tracing
DSD-properties-rules
debug
diff --git a/Documentation/firmware-guide/acpi/method-customizing.rst b/Documentation/firmware-guide/acpi/method-customizing.rst
deleted file mode 100644
index de3ebcaed4cf..000000000000
--- a/Documentation/firmware-guide/acpi/method-customizing.rst
+++ /dev/null
@@ -1,89 +0,0 @@
-.. SPDX-License-Identifier: GPL-2.0
-
-=======================================
-Linux ACPI Custom Control Method How To
-=======================================
-
-:Author: Zhang Rui <rui.zhang@intel.com>
-
-
-Linux supports customizing ACPI control methods at runtime.
-
-Users can use this to:
-
-1. override an existing method which may not work correctly,
- or just for debugging purposes.
-2. insert a completely new method in order to create a missing
- method such as _OFF, _ON, _STA, _INI, etc.
-
-For these cases, it is far simpler to dynamically install a single
-control method rather than override the entire DSDT, because kernel
-rebuild/reboot is not needed and test result can be got in minutes.
-
-.. note::
-
- - Only ACPI METHOD can be overridden, any other object types like
- "Device", "OperationRegion", are not recognized. Methods
- declared inside scope operators are also not supported.
-
- - The same ACPI control method can be overridden for many times,
- and it's always the latest one that used by Linux/kernel.
-
- - To get the ACPI debug object output (Store (AAAA, Debug)),
- please run::
-
- echo 1 > /sys/module/acpi/parameters/aml_debug_output
-
-
-1. override an existing method
-==============================
-a) get the ACPI table via ACPI sysfs I/F. e.g. to get the DSDT,
- just run "cat /sys/firmware/acpi/tables/DSDT > /tmp/dsdt.dat"
-b) disassemble the table by running "iasl -d dsdt.dat".
-c) rewrite the ASL code of the method and save it in a new file,
-d) package the new file (psr.asl) to an ACPI table format.
- Here is an example of a customized \_SB._AC._PSR method::
-
- DefinitionBlock ("", "SSDT", 1, "", "", 0x20080715)
- {
- Method (\_SB_.AC._PSR, 0, NotSerialized)
- {
- Store ("In AC _PSR", Debug)
- Return (ACON)
- }
- }
-
- Note that the full pathname of the method in ACPI namespace
- should be used.
-e) assemble the file to generate the AML code of the method.
- e.g. "iasl -vw 6084 psr.asl" (psr.aml is generated as a result)
- If parameter "-vw 6084" is not supported by your iASL compiler,
- please try a newer version.
-f) mount debugfs by "mount -t debugfs none /sys/kernel/debug"
-g) override the old method via the debugfs by running
- "cat /tmp/psr.aml > /sys/kernel/debug/acpi/custom_method"
-
-2. insert a new method
-======================
-This is easier than overriding an existing method.
-We just need to create the ASL code of the method we want to
-insert and then follow the step c) ~ g) in section 1.
-
-3. undo your changes
-====================
-The "undo" operation is not supported for a new inserted method
-right now, i.e. we can not remove a method currently.
-For an overridden method, in order to undo your changes, please
-save a copy of the method original ASL code in step c) section 1,
-and redo step c) ~ g) to override the method with the original one.
-
-
-.. note:: We can use a kernel with multiple custom ACPI method running,
- But each individual write to debugfs can implement a SINGLE
- method override. i.e. if we want to insert/override multiple
- ACPI methods, we need to redo step c) ~ g) for multiple times.
-
-.. note:: Be aware that root can mis-use this driver to modify arbitrary
- memory and gain additional rights, if root's privileges got
- restricted (for example if root is not allowed to load additional
- modules after boot).