Merge an update related to ACPI debugging and ACPI documentation updates
for 6.17-rc1:
- Enable CONFIG_ACPI_DEBUG by default to make it easier to get ACPI
debug messages from OEM platforms (Mario Limonciello)
- Fix parent device references in ASL examples in the ACPI
documentation and fix spelling and style in the gpio-properties
documentation in firmware-guide (Andy Shevchenko)
* acpi-debug:
ACPI: Enable CONFIG_ACPI_DEBUG by default
* acpi-docs:
Documentation: ACPI: Fix parent device references
Documentation: firmware-guide: gpio-properties: Spelling and style fixes
The _CRS resources in many cases want to have ResourceSource field
to be a type of ACPI String. This means that to compile properly
we need to enclosure the name path into double quotes. This will
in practice defer the interpretation to a run-time stage, However,
this may be interpreted differently on different OSes and ACPI
interpreter implementations. In particular ACPICA might not correctly
recognize the leading '^' (caret) character and will not resolve
the relative name path properly. On top of that, this piece may be
used in SSDTs which are loaded after the DSDT and on itself may also
not resolve relative name paths outside of their own scopes.
With this all said, fix documentation to use fully-qualified name
paths always to avoid any misinterpretations, which is proven to
work.
Fixes: 8eb5c87a92 ("i2c: add ACPI support for I2C mux ports")
Reported-by: Yevhen Kondrashyn <e.kondrashyn@gmail.com>
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://patch.msgid.link/20250710170225.961303-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The ACPI namespace has always started with LNXSYSTM, not LNXSYSTEM.
Fix the documentation accordingly.
Signed-off-by: John Watts <contact@jookia.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Pull more ACPI updates from Rafael Wysocki:
"These update ACPI documentation and kerneldoc comments.
Specifics:
- Add markup to generate links from footnotes in the ACPI enumeration
document (Chris Packham)
- Update the handle_eject_request() kerneldoc comment to document the
arguments of the function and improve kerneldoc comments for ACPI
suspend and hibernation functions (Yang Li)"
* tag 'acpi-6.9-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI: PM: Improve kerneldoc comments for suspend and hibernation functions
ACPI: docs: enumeration: Make footnotes links
ACPI: Document handle_eject_request() arguments
Pull CXL updates from Dan Williams:
"CXL has mechanisms to enumerate the performance characteristics of
memory devices. Those mechanisms allow Linux to build the equivalent
of ACPI SRAT, SLIT, and HMAT tables dynamically at runtime. That
capability is necessary because static ACPI can not represent dynamic
CXL configurations (and reconfigurations).
So, building on the v6.8 work to add "Quality of Service" enumeration,
this update plumbs CXL "access coordinates" (read/write access latency
and bandwidth) in all the same places that ACPI HMAT feeds similar
data. Follow-on patches from the -mm side can then use that data to
feed mechanisms like mm/memory-tiers.c. Greg has acked the touch to
drivers/base/.
The other feature update this cycle is support for CXL error injection
via the ACPI EINJ module. That facility enables injection of bus
protocol errors provided the user knows the magic address values to
insert in the interface. To hide that magic, and make this easier to
use, new error injection attributes were added to CXL debugfs. That
interface injects the errors relative to a CXL object rather than
require user tooling to know how to lookup and inject RCRB (Root
Complex Register Block) addresses into the raw EINJ debugfs interface.
It received some helpful review comments from Tony, but no explicit
acks from the ACPI side. The primary user visible change for existing
EINJ users is that they may find that einj.ko was already loaded by
cxl_core.ko. Previously, einj.ko was only loaded on demand.
The usual collection of miscellaneous cleanups are also present this
cycle.
Summary:
- Supplement ACPI HMAT reported memory performance with native CXL
memory performance enumeration
- Add support for CXL error injection via the ACPI EINJ mechanism
- Cleanup CXL DOE and CDAT integration
- Miscellaneous cleanups and fixes"
* tag 'cxl-for-6.9' of git://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl: (21 commits)
Documentation/ABI/testing/debugfs-cxl: Fix "Unexpected indentation"
lib/firmware_table: Provide buffer length argument to cdat_table_parse()
cxl/pci: Get rid of pointer arithmetic reading CDAT table
cxl/pci: Rename DOE mailbox handle to doe_mb
cxl: Fix the incorrect assignment of SSLBIS entry pointer initial location
cxl/core: Add CXL EINJ debugfs files
EINJ, Documentation: Update EINJ kernel doc
EINJ: Add CXL error type support
EINJ: Migrate to a platform driver
cxl/region: Deal with numa nodes not enumerated by SRAT
cxl/region: Add memory hotplug notifier for cxl region
cxl/region: Add sysfs attribute for locality attributes of CXL regions
cxl/region: Calculate performance data for a region
cxl: Set cxlmd->endpoint before adding port device
cxl: Move QoS class to be calculated from the nearest CPU
cxl: Split out host bridge access coordinates
cxl: Split out combine_coordinates() for common shared usage
ACPI: HMAT / cxl: Add retrieval of generic port coordinates for both access classes
ACPI: HMAT: Introduce 2 levels of generic port access class
base/node / ACPI: Enumerate node access class for 'struct access_coordinate'
...
The ACPI custom_method debugfs interface is security-sensitive and
concurrent access to it is broken [1].
Moreover, the recipe for preparing a customized version of a given
control method has changed at one point due to ACPICA changes, which
has not been reflected in its documentation, so whoever used it before
has had to adapt and it had gone unnoticed for a long time.
This interface was a bad idea to start with and its implementation is
fragile at the design level. It's been always conceptually questionable,
problematic from the security standpoint and implemented poorly.
Patches fixing its most apparent functional issues (for example, [2]) don't
actually address much of the above.
Granted, at the time it was introduced, there was no alternative, but
there is the AML debugger in the kernel now and there is the configfs
interface allowing custom ACPI tables to be loaded. The former can be
used for extensive AML debugging and the latter can be use for testing
new AML. [3]
Accordingly, drop custom_method along with its (outdated anyway)
documentation.
Link: https://lore.kernel.org/linux-acpi/20221227063335.61474-1-zh.nvgt@gmail.com/ # [1]
Link: https://lore.kernel.org/linux-acpi/20231111132402.4142-1-shiqiang.deng213@gmail.com/ [2]
Link: https://stackoverflow.com/questions/62849113/how-to-unload-an-overlay-loaded-using-acpi-config-sysfs # [3]
Reported-by: Hang Zhang <zh.nvgt@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Zhang Rui <rui.zhang@intel.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
In some cases, ACPI drivers are implemented as a way to manage devices
enumerated with the help of the platform firmware through ACPI.
This might be confusing, since the preferred way to implement a driver
for a device that cannot be enumerated natively, is a platform
driver, as stated in the documentation.
Clarify relationships between ACPI device objects, platform devices and
ACPI Namespace entries.
Suggested-by: Elena Reshetova <elena.reshetova@intel.com>
Co-developed-by: Michal Wilczynski <michal.wilczynski@intel.com>
Signed-off-by: Michal Wilczynski <michal.wilczynski@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Pull documentation updates from Jonathan Corbet:
"Documentation work keeps chugging along; this includes:
- Work from Carlos Bilbao to integrate rustdoc output into the
generated HTML documentation. This took some work to figure out how
to do it without slowing the docs build and without creating people
who don't have Rust installed, but Carlos got there
- Move the loongarch and mips architecture documentation under
Documentation/arch/
- Some more maintainer documentation from Jakub
... plus the usual assortment of updates, translations, and fixes"
* tag 'docs-6.6' of git://git.lwn.net/linux: (56 commits)
Docu: genericirq.rst: fix irq-example
input: docs: pxrc: remove reference to phoenix-sim
Documentation: serial-console: Fix literal block marker
docs/mm: remove references to hmm_mirror ops and clean typos
docs/zh_CN: correct regi_chg(),regi_add() to region_chg(),region_add()
Documentation: Fix typos
Documentation/ABI: Fix typos
scripts: kernel-doc: fix macro handling in enums
scripts: kernel-doc: parse DEFINE_DMA_UNMAP_[ADDR|LEN]
Documentation: riscv: Update boot image header since EFI stub is supported
Documentation: riscv: Add early boot document
Documentation: arm: Add bootargs to the table of added DT parameters
docs: kernel-parameters: Refer to the correct bitmap function
doc: update params of memhp_default_state=
docs: Add book to process/kernel-docs.rst
docs: sparse: fix invalid link addresses
docs: vfs: clean up after the iterate() removal
docs: Add a section on surveys to the researcher guidelines
docs: move mips under arch
docs: move loongarch under arch
...
I²C peripheral devices that are connected to the controller are
represented in the Linux kernel as objects of the struct i2c_client.
Fix this in the documentation.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rjw@rjwysocki.net>
Clarify the Explicit and Implicit meanings in the table of Pull Bias.
While at it, distinguish pull bias keywords used in ACPI by using bold
font in the table of the respective terms.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Correct spelling problems for Documentation/firmware-guide/ as reported
by codespell.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Merge miscellaneous ACPI material, ACPI tools changes and ACPI
documentation updates for 6.1-rc1:
- Drop references to non-functional 01.org/linux-acpi web site from
MAINTAINERS and Kconfig help texts (Rafael Wysocki).
- Replace strlcpy() with unused retval with strscpy() in the ACPI
support code (Wolfram Sang).
- Do not initialize ret in main() in the pfrut utility (Shi junming).
- Drop useless ACPI DSDT override documentation (Rafael Wysocki).
- Fix a few typos and wording mistakes in the ACPI device enumeration
documentation (Jean Delvare).
* acpi-misc:
MAINTAINERS: Drop records pointing to 01.org/linux-acpi
ACPI: Kconfig: Drop link to https://01.org/linux-acpi
ACPI: DPTF: Drop stale link from Kconfig help
ACPI: move from strlcpy() with unused retval to strscpy()
* acpi-tools:
ACPI: tools: pfrut: Do not initialize ret in main()
* acpi-docs:
ACPI: docs: Drop useless DSDT override documentation
ACPI: docs: enumeration: Fix a few typos and wording mistakes
Originally, when there was some custom ASL needed for Linux, the
guidance for Linux-friendly OEMs was to introduced a new string in the
APCI tables and discuss it on the kernel mailing lists.
This lead to 3 strings being introduced. Those strings now have the
original problems fixed in the kernel and have since been removed.
The kernel no longer advertises any custom Linux-* _OSI strings for
OEM use.
It was discovered that these removed strings were actually being abused
to detect Linux for unrelated reasons, so drop the encouragement for
new ones to be added.
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
