For ITS, MSI functionality consists on building domain stack and
during that process we need to reference to domain stack components
e.g. before we create new DOMAIN_BUS_PCI_MSI domain we need to specify
its DOMAIN_BUS_NEXUS parent domain. In order to manage that process
properly, maintain list which elements contain domain token
(unique for MSI domain stack) and ITS ID: iort_register_domain_token()
and iort_deregister_domain_token(). Then retrieve domain token
any time later with ITS ID being key off: iort_find_domain_token().
With domain token and domain type we are able to find corresponding
IRQ domain.
Since IORT is prepared to describe MSI domain on a per-device basis,
use existing IORT helpers and implement two calls:
1. iort_msi_map_rid() to map MSI RID for a device
2. iort_get_device_domain() to find domain token for a device
Signed-off-by: Tomasz Nowicki <tn@semihalf.com>
Acked-by: Rafael J. Wysocki <rjw@rjwysocki.net>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
IORT shows representation of IO topology for ARM based systems.
It describes how various components are connected together on
parent-child basis e.g. PCI RC -> SMMU -> ITS. Also see IORT spec.
http://infocenter.arm.com/help/topic/com.arm.doc.den0049b/DEN0049B_IO_Remapping_Table.pdf
Initial support allows to detect IORT table presence and save its
root pointer obtained through acpi_get_table(). The pointer validity
depends on acpi_gbl_permanent_mmap because if acpi_gbl_permanent_mmap
is not set while using IORT nodes we would dereference unmapped pointers.
For the aforementioned reason call acpi_iort_init() from acpi_init()
which guarantees acpi_gbl_permanent_mmap to be set at that point.
Add generic helpers which are helpful for scanning and retrieving
information from IORT table content. List of the most important helpers:
- iort_find_dev_node() finds IORT node for a given device
- iort_node_map_rid() maps device RID and returns IORT node which provides
final translation
IORT support is placed under drivers/acpi/arm64/ new directory due to its
ARM64 specific nature. The code there is considered only for ARM64.
The long term plan is to keep all ARM64 specific tables support
in this place e.g. GTDT table.
Signed-off-by: Tomasz Nowicki <tn@semihalf.com>
Acked-by: Rafael J. Wysocki <rjw@rjwysocki.net>
Reviewed-by: Hanjun Guo <hanjun.guo@linaro.org>
Reviewed-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Pull libnvdimm fixes from Dan Williams:
"nvdimm fixes for v4.8, two of them are tagged for -stable:
- Fix devm_memremap_pages() to use track_pfn_insert(). Otherwise,
DAX pmd mappings end up with an uncached pgprot, and unusable
performance for the device-dax interface. The device-dax interface
appeared in 4.7 so this is tagged for -stable.
- Fix a couple VM_BUG_ON() checks in the show_smaps() path to
understand DAX pmd entries. This fix is tagged for -stable.
- Fix a mis-merge of the nfit machine-check handler to flip the
polarity of an if() to match the final version of the patch that
Vishal sent for 4.8-rc1. Without this the nfit machine check
handler never detects / inserts new 'badblocks' entries which
applications use to identify lost portions of files.
- For test purposes, fix the nvdimm_clear_poison() path to operate on
legacy / simulated nvdimm memory ranges. Without this fix a test
can set badblocks, but never clear them on these ranges.
- Fix the range checking done by dax_dev_pmd_fault(). This is not
tagged for -stable since this problem is mitigated by specifying
aligned resources at device-dax setup time.
These patches have appeared in a next release over the past week. The
recent rebase you can see in the timestamps was to drop an invalid fix
as identified by the updated device-dax unit tests [1]. The -mm
touches have an ack from Andrew"
[1]: "[ndctl PATCH 0/3] device-dax test for recent kernel bugs"
https://lists.01.org/pipermail/linux-nvdimm/2016-September/006855.html
* 'libnvdimm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
libnvdimm: allow legacy (e820) pmem region to clear bad blocks
nfit, mce: Fix SPA matching logic in MCE handler
mm: fix cache mode of dax pmd mappings
mm: fix show_smap() for zone_device-pmd ranges
dax: fix mapping size check
On ACPI ARM based systems the GIC interrupt controller
and corresponding interrupt model permit only the high
polarity for level interrupts.
ACPI firmware describes PCI legacy IRQs through entries
in the _PRT objects. Entries in the _PRT can be of two types:
- Static: not configurable, trigger/polarity default to level-low,
_PRT entry defines the global GSI interrupt number
- Configurable: _PRT interrupt entry contains a reference to the
corresponding PCI interrupt link device (that in turn provides the
interrupt descriptor through its _CRS/_PRS methods)
Configurable IRQ entries are not currently allowed by the ACPI
specification on ARM since they can only be used for interrupt pins that
are routable, as per ACPI specifications (version 6.1, 6.2.13):
"[...] There are two ways that _PRT can be used. Typically, the
interrupt input that a given PCI interrupt is on is configurable. For
example, a given PCI interrupt might be configured for either IRQ 10 or
11 on an 8259 interrupt controller. In this model, each interrupt is
represented in the ACPI namespace as a PCI Interrupt Link Device. [...]"
ARM platforms GIC configurations do not allow dynamic IRQ routing,
since routing is statically laid out at synthesis time; therefore PCI
interrupt links cannot be used for PCI legacy IRQ descriptions in the
_PRT on ARM systems.
On the other hand, current core ACPI code handling PCI legacy IRQs
consider IRQ trigger/polarity for static _PRT entries as level-low.
On ARM systems with a GIC interrupt controller and corresponding
ACPI interrupt model this does not work in that GIC interrupt
controller is only capable of handling level interrupts whose
polarity is high (for PCI legacy IRQs - that are level-low by
specification - this means that the legacy IRQs are inverted before
reaching the interrupt controller pin), resulting in IRQ allocation
failures such as:
genirq: Setting trigger mode 8 for irq 18 failed (gic_set_type+0x0/0x48)
Change the default polarity for PCI legacy IRQs to high on systems
booting wth ACPI on platforms with a GIC interrupt controller model,
fixing the discrepancy between specification and HW behaviour.
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Duc Dang <dhdang@apm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPICA commit f564d57c6501b97a2871f0b4c048e79910f71783
This patch tunes MTX_TABLES into a leaf lock by always ensuring it is
released before holding other locks.
This patch also collects all table loading related functions into
acpi_tb_load_table() (invoked by load_table opcode) and
acpi_tb_install_and_load_table() (invoked by Load opcode and acpi_load_table()) so
that we can have lock tuning code collected at the boundary of these 2
functions. Lv Zheng.
Link: https://github.com/acpica/acpica/commit/f564d57c
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Dutch Guy <lucht_piloot@gmx.net>
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>
ACPICA commit 767ee53354e0c4b7e8e7c57c6dd7bf569f0d52bb
There are issues related to the namespace/interpreter locks, which causes
several ACPI functionalities not specification compliant. The lock issues
were detectec when we were trying to fix the functionalities (please see
Link # [1] for the details).
What's the lock issues? Let's first look into the namespace/interpreter
lock usages inside of the object evaluation and the table loading which are
the key AML interpretion code paths:
Table loading:
acpi_ns_load_table
L(Namespace)
acpi_ns_parse_table
acpi_ns_one_complete_parse(LOAD_PASS1/LOAD_PASS2)
acpi_ds_load1_begion_op
acpi_ds_load1_end_op
acpi_ds_load2_begion_op
acpi_ds_load2_end_op
U(Namespace)
Object evaluation:
acpi_ns_evaluate
L(Interpreter)
acpi_ps_execute_method
acpi_ds_exec_begin_op
acpi_ds_exec_end_op
U(Interpreter)
acpi_ns_load_table
L(Namespace)
U(Namespace)
acpi_ev_initialize_region
L(Namespace)
U(Namespace)
address_space.Setup
address_space.Handler
acpi_os_wait_semaphore
acpi_os_acquire_mutex
acpi_os_sleep
L(Interpreter)
U(Interpreter)
L(Interpreter)
acpi_ex_resolve_node_to_value
U(Interpreter)
acpi_ns_check_return_value
Where:
1. L(Interpreter) means acquire(MTX_INTERPRETER);
2. U(Interpreter) means release(MTX_INTERPRETER);
3. L(Namespace) means acquire(MTX_NAMESPACE);
4. U(Namespace) means release(MTX_NAMESPACE);
We can see that acpi_ns_exec_module_code() (which invokes acpi_ns_evaluate) is
implemented in a deferred way just in order to avoid to reacquire the
namespace lock. This is in fact the root cause of many other ACPICA issues:
1. We now know for sure that the module code should be executed right in
place by the Windows AML interpreter. So in the current design, if
the region initializations/accesses or the table loadings (where the
namespace surely should be locked again) happening during the table
loading period, dead lock could happen because ACPICA never unlocks the
namespace during the AML interpretion.
2. ACPICA interpreter just ensures that all static namespace nodes (named
objects created during the acpi_load_tables()) are created
(acpi_ns_lookup()) with the correct lock held, but doesn't ensure that
the named objects created by the control method are created with the
same correct lock held. It requires the control methods to be executed
in a serial way after "loading a table", that's why ACPICA requires
method auto serialization.
This patch fixes these software design issues by extending interpreter
enter/exit APIs to hold both interpreter/namespace locks to ensure the lock
order correctness, so that we can get these code paths:
Table loading:
acpi_ns_load_table
E(Interpreter)
acpi_ns_parse_table
acpi_ns_one_complete_parse
acpi_ns_execute_table
X(Interpreter)
acpi_ns_load_table
acpi_ev_initialize_region
address_space.Setup
address_space.Handler
acpi_os_wait_semaphore
acpi_os_acquire_mutex
acpi_os_sleep
E(Interpreter)
X(Interpreter)
Object evaluation:
acpi_ns_evaluate
E(Interpreter)
acpi_ps_execute_method
X(Interpreter)
acpi_ns_load_table
acpi_ev_initialize_region
address_space.Setup
address_space.Handler
acpi_os_wait_semaphore
acpi_os_acquire_mutex
acpi_os_sleep
E(Interpreter)
X(Interpreter)
Where:
1. E(Interpreter) means acquire(MTX_INTERPRETER, MTX_NAMESPACE);
2. X(Interpreter) means release(MTX_NAMESPACE, MTX_INTERPRETER);
After this change, we can see:
1. All namespace nodes creations are locked by the namespace lock.
2. All namespace nodes referencing are locked with the same lock.
3. But we also can notice a defact that, all namespace nodes deletions
could be affected by this change. As a consequence,
acpi_ns_delete_namespace_subtree() may delete a static namespace node that
is still referenced by the interpreter (for example, the parser scopes).
Currently, we needn't worry about the last defact because in ACPICA, table
unloading is not fully functioning, its design strictly relies on the fact
that when the namespace deletion happens, either the AML table or the OSPMs
should have been notified and thus either the AML table or the OSPMs
shouldn't reference deletion-related namespace nodes during the namespace
deletion. And this change still works with the above restrictions applied.
While making this a-step-forward helps us to correct the wrong grammar to
pull many things back to the correct rail. And pulling things back to the
correct rail in return makes it possible for us to support fully
functioning table unloading after doing many cleanups.
While this patch is generated, all namespace locks are examined to ensure
that they can meet either of the following pattens:
1. L(Namespace)
U(Namespace)
2. E(Interpreter)
X(Interpreter)
3. E(Interpreter)
X(Interpreter)
L(Namespace)
U(Namespace)
E(Interpreter)
X(Interpreter)
We ensure this by adding X(Interpreter)/E(Interpreter) or removing
U(Namespace)/L(Namespace) for those currently are executed in the following
order:
E(Interpreter)
L(Namespace)
U(Namespace)
X(Interpreter)
And adding E(Interpreter)/X(Interpreter) for those currently are executed
in the following order:
X(Interpreter)
E(Interpreter)
Originally, the interpreter lock is held for the execution AML opcodes, the
namespace lock is held for the named object creation AML opcodes. Since
they are actually same in MS interpreter (can all be executed during the
table loading), we can combine the 2 locks and tune the locking code better
in this way. Lv Zheng.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=153541 # [1]
Link: https://bugzilla.kernel.org/show_bug.cgi?id=121701 # [1]
Link: https://bugs.acpica.org/show_bug.cgi?id=1323
Link: https://github.com/acpica/acpica/commit/767ee533
Reported-and-tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reported-and-tested-by: Greg White <gwhite@kupulau.com>
Reported-and-tested-by: Dutch Guy <lucht_piloot@gmx.net>
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>
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>
ACPICA commit aaace77db4c3b267a65b75c33f84ace6f65bbcf7
Originally, when acpi_gbl_use32_bit_fadt_addresses is TRUE, GAS override can
only happen when the Address field mismatches.
According to the investigation result, Windows may favor 32-bit FADT
addresses in some cases. So we need this quirk working after enabling full
GAS support. This requires us to override GAS access_size/bit_width/bit_offset
fields as long as acpi_gbl_use32_bit_fadt_addresses is TRUE.
This patch enhances this quirk mechanism to make it working with full GAS
support. Lv Zheng.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=151501
Link: https://github.com/acpica/acpica/commit/aaace77d
Reported-and-tested-by: Andrey Skvortsov <andrej.skvortzov@gmail.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>
ACPICA commit ed6a5fbc694f3a27d93014391aa9a6f6fe490461
This patch adds 2 new table events to indicate table
installation/uninstallation.
Currently, as ACPICA never uninstalls tables, this patch thus only adds
table handler invocation for the table installation event. Lv Zheng.
The 2 events are to be used to fix a sysfs table handling issue related to
LoadTable opcode (see Link # [1] below). The actual sysfs fixing code is
not included, the sysfs fixes will be sent as separate patches.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=150841 # [1]
Link: https://github.com/acpica/acpica/commit/ed6a5fbc
Reported-by: Jason Voelz <jason.voelz@intel.com>
Reported-by: Francisco Leoner <francisco.j.lenoer.soto@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>
ACPICA commit e2e72a351201fd58e4694418859ae2c247dafca0
Consolidate multiple versions of strtoul64 to one common version.
limit possible bases to either 10 or 16.
Handles both implicit and explicit conversions.
Added a 2-character ascii-to-hex function for GPEs and buffers.
Adds a new file, utstrtoul64.c
Link: https://github.com/acpica/acpica/commit/e2e72a35
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
There are issues related to the boot_ec:
1. If acpi_ec_remove() is invoked, boot_ec will also be freed, this is not
expected as the boot_ec could be enumerated via ECDT.
2. Address space handler installation/unstallation lead to unexpected _REG
evaluations.
This patch adds acpi_is_boot_ec() check to be used to fix the above issues.
However, since acpi_ec_remove() actually won't be invoked, this patch
doesn't handle the reference counting of "struct acpi_ec", it only ensures
the correctness of the boot_ec destruction during the boot.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=153511
Reported-and-tested-by: Jonh Henderson <jw.hendy@gmail.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In order to support full ECDT (driving the ECDT EC after probing the
namespace EC), we need to change our EC device alloc/free algorithm, ensure
not to free old boot EC before qualifying new boot EC.
This patch achieves this by cleaning up first_ec/boot_ec logic:
1. first_ec: used to perform transactions, so it is assigned in new
acpi_ec_setup() function.
2. boot_ec: used to track early EC device, so it is assigned in new
acpi_config_boot_ec() function which explictly tells the driver to save
the EC device as early EC device.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=115021
Reported-and-tested-by: Luya Tshimbalanga <luya@fedoraproject.org>
Tested-by: Jonh Henderson <jw.hendy@gmail.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Since struct cpudata is defined in a header file, add prefix cppc_ to
make it not a generic name. Otherwise it causes compile issue in locally
define structure with the same name.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The CPPC registers can also be accessed via functional fixed hardware
addresse(FFH) in X86. Add support by modifying cpc_read and cpc_write to
be able to read/write MSRs on x86 platform on per cpu basis.
Also with this change, acpi_cppc_processor_probe doesn't bail out if
address space id is not equal to PCC or memory address space and FFH
is supported on the system.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Some newer x86 platforms have support for both _CPC and _PSS object. So
kernel config can have both ACPI_CPU_FREQ_PSS and ACPI_CPPC_LIB. So remove
restriction for ACPI_CPPC_LIB to build only when ACPI_CPU_FREQ_PSS is not
defined.
Also for legacy systems with only _PSS, we shouldn't bail out if
acpi_cppc_processor_probe() fails, if ACPI_CPU_FREQ_PSS is also defined.
Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit e647b53227 ("ACPI: Add early device probing infrastructure")
introduced code that allows inserting driver specific
struct acpi_probe_entry probe entries into ACPI linker sections
(one per-subsystem, eg irqchip, clocksource) that are then walked
to retrieve the data and function hooks required to probe the
respective kernel components.
Probing for all entries in a section is triggered through
the __acpi_probe_device_table() function, that in turn, according
to the table ID a given probe entry reports parses the table
with the function retrieved from the respective section structures
(ie struct acpi_probe_entry). Owing to the current ACPI table
parsing implementation, the __acpi_probe_device_table() function
has to share global variables with the acpi_match_madt() function, so
in order to guarantee mutual exclusion locking is required
between the two functions.
Current kernel code implements the locking through the acpi_probe_lock
spinlock; this has the side effect of requiring all code called
within the lock (ie struct acpi_probe_entry.probe_{table/subtbl} hooks)
not to sleep.
However, kernel subsystems that make use of the early probing
infrastructure are relying on kernel APIs that may sleep (eg
irq_domain_alloc_fwnode(), among others) in the function calls
pointed at by struct acpi_probe_entry.{probe_table/subtbl} entries
(eg gic_v2_acpi_init()), which is a bug.
Since __acpi_probe_device_table() is called from context
that is allowed to sleep the acpi_probe_lock spinlock can be replaced
with a mutex; this fixes the issue whilst still guaranteeing
mutual exclusion.
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Fixes: e647b53227 (ACPI: Add early device probing infrastructure)
Cc: 4.4+ <stable@vger.kernel.org> # 4.4+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The function acpi_parse_entries_array() has a limiting parameter,
max_entries, which tells the function to stop looking at subtables
once that limit has been reached. If the limit is reached, it is
reported. However, the logic is incorrect in that the loop to
examine all subtables will always report that zero subtables have
been ignored since it does not continue once the max_entries have
been reached.
One approach to fixing this would be to correct the logic so that
all subtables are examined, even if we have hit the max_entries, but
without executing all the callback functions. This could be risky
since we cannot guarantee that no callback will ever have side effects
that another callback depends on to work correctly.
So, the simplest approach is to just remove the part of the error
message that will always be incorrect.
Signed-off-by: Al Stone <ahs3@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The acpi_parse_entries_array() function currently returns the very first
time there is any error found by one of the callback functions, or if one
of the callbacks returns a non-zero value. However, the ACPI subtables
being traversed could still have valid entries that could be used by one
of the callback functions. And, if the comments are correct, that is
what should happen -- always traverse all of the subtables, calling as
many of the callbacks as possible.
This patch makes the function consistent with its description so that it
will properly invoke all callbacks for all matching entries, for all
subtables, instead of stopping abruptly as it does today.
This does change the semantics of using acpi_parse_entries_array(). In
examining all users of the function, none of them rely on the current
behavior; that is, there appears to be no assumption that either all
subtables are traversed and all callbacks invoked, or that the function
will return immediately on any error from a callback. Each callback
operates independently. Hence, there should be no functional change
due to this change in semantics.
Future patches being prepared will rely on this new behavior; indeed,
they were written assuming the acpi_parse_entries_array() function
operated as its comments describe. For example, a callback that
counts the number of subtables of a specific type can now be assured
that as many subtables as possible have been enumerated.
Signed-off-by: Al Stone <ahs3@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The static function acpi_parse_entries_array() is provided an array of
type struct acpi_subtable_proc that has a callback function and a count.
The count should reflect how many times the callback has been called.
However, the current code only increments the 0th element of the array,
regardless of the number of entries in the array, or which callback has
been invoked. The result is that we know the total number of callbacks
made but we cannot determine which callbacks were made, nor how often.
The fix is to index into the array of structs and increment the proper
counts.
There is one place in the x86 code for acpi_parse_madt_lapic_entries()
where the counts for each callback are used. If no LAPICs *and* no
X2APICs are found, an ENODEV is supposed to be returned; as it stands,
the count of X2APICs will always be zero, regardless of what is in the
MADT. Should there be no LAPICs, ENODEV will be returned in error, if
there are X2APICs in the MADT.
Otherwise, there are no other functional consequences of the count being
done as it currently is; all other uses simply check that the return value
from acpi_parse_entries_array() or passed back via its callers is either
non-zero, an error, or in one case just ignored.
In future patches, I will also need these counts to be correct; I need
to count the number of instances of subtables of certain types within
the MADT to determine whether or not an ACPI IORT is required or not,
and report when it is not present when it should be.
Signed-off-by: Al Stone <ahs3@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The UART driver, dw8250.c, needs some details regarding the
Designware UART. For ACPI enumerated devices the values are
hard-coded, but since the driver also reads the values from
device properties, providing them with build-in properties.
This allows us to later remove the hard-coded values from
the driver.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The UART driver, dw8250.c, needs some details regarding the
Designware UART. For ACPI enumerated devices the values are
hard-coded, but since the driver also reads the values from
device properties, providing them with build-in properties.
This allows us to later remove the hard-coded values from
the driver.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
On most platforms, _LID returning value, lid open/close events are all
reliable, but there are exceptions. Some AML tables report wrong initial
lid state [1], and some of them never report lid open state [2].
The usage model on such buggy platforms is:
1. The initial lid state returned from _LID is not reliable;
2. The lid open event is not reliable;
3. The lid close event is always reliable, used by the platform firmware to
trigger OSPM power saving operations.
This usage model is not compliant to the Linux SW_LID model as the Linux
userspace is very strict to the reliability of the open events.
In order not to trigger issues on such buggy platforms, the ACPI button
driver currently implements a lid_init_state=open quirk to send additional
"open" event after resuming. However, this is still not sufficient because:
1. Some special usage models (e.x., the dark resume scenario) cannot be
supported by this mode.
2. If a "close" event is not used to trigger "suspend", then the subsequent
"close" events cannot be seen by the userspace.
So we need to stop sending the additional "open" event and switch the
driver to lid_init_state=ignore mode and make sure the platform triggered
events can be reliably delivered to the userspace. The userspace programs
then can be changed to not to be strict to the "open" events on such buggy
platforms.
Why will the subsequent "close" events be lost? This is because the input
layer automatically filters redundant events for switch events. Thus given
that the buggy AML tables do not guarantee paired "open"/"close" events,
the ACPI button driver currently is not able to guarantee that the platform
triggered reliable events can be always be seen by the userspace via
SW_LID.
This patch adds a mechanism to insert lid events as a compensation for the
platform triggered ones to form a complete event switches in order to make
sure that the platform triggered events can always be reliably delivered
to the userspace. This essentially guarantees that the platform triggered
reliable "close" events will always be relibly delivered to the userspace.
However this mechanism is not suitable for lid_init_state=open/method as
it should not send the complement switch event for the unreliable initial
lid state notification. 2 unreliable events can trigger unexpected
behavior. Thus this patch only implements this mechanism for
lid_init_state=ignore.
Known issues:
1. Possible alternative approach
This approach is based on the fact that Linux requires a switch event
type for LID events. Another approach is to use key event type to
implement ACPI lid events.
With SW event type, since ACPI button driver inserts wrong lid events,
there could be a potential issue that an "open" event issued from some
AML update methods could result in a wrong "close" event to be delivered
to the userspace. While using KEY event type, there is no such problem.
However there may not be such a kind of real case, and if there is such
a case, it is worked around in this patch as the complement switch event
is only generated for "close" event in order to deliver the reliable
"close" event to the userspace.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=89211 # [1]
Link: https://bugzilla.kernel.org/show_bug.cgi?id=106151 # [1]
Link: https://bugzilla.kernel.org/show_bug.cgi?id=106941 # [2]
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Suggested-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
PCC status field exposes an error bit(2) to indicate any errors during
the execution of last comamnd. This patch checks the error bit before
notifying success/failure to the cpufreq driver.
Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
There are several global variables in cppc driver that are related
to PCC channel used for CPPC. This patch collects all such
information into a single consolidated structure(cppc_pcc_data).
Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The CPPC tables contain entries for per CPU feedback counters which
allows us to compute the delivered performance over a given interval
of time.
The math for delivered performance per the CPPCv5.0+ spec is:
reference perf * delta(delivered perf ctr)/delta(ref perf ctr)
Maintaining deltas of the counters in the kernel is messy, as it
depends on when the reads are triggered. (e.g. via the cpufreq
->get() interface). Also the ->get() interace only returns one
value, so cant return raw values. So instead, leave it to userspace
to keep track of raw values and do its math for CPUs it cares about.
delivered and reference perf counters are exposed via the same
sysfs file to avoid the potential "skid", if these values are read
individually from userspace.
Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org>
Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Compute the expected transition latency for frequency transitions
using the values from the PCCT tables when the desired perf
register is in PCC.
Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org>
Reviewed-by: Alexey Klimov <alexey.klimov@arm.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
CPPC defined in section 8.4.7 of ACPI 6.0 specification suggests
"To amortize the cost of PCC transactions, OSPM should read or write
all PCC registers via a single read or write command when possible"
This patch enables opportunistic batching of frequency transition
requests whenever the request happen to overlap in time.
Currently the access to pcc is serialized by a spin lock which does
not scale well as we increase the number of cores in the system. This
patch improves the scalability by allowing the differnt CPU cores to
update PCC subspace in parallel and by batching requests which will
reduce the certain types of operation(checking command completion bit,
ringing doorbell) by a significant margin.
Profiling shows significant improvement in the overall effeciency
to service freq. transition requests. With this patch we observe close
to 30% of the frequency transition requests being batched with other
requests while running apache bench on a ARM platform with 6
independent domains(or sets of related cpus).
Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
We need to acquire pcc_lock only when we are accessing registers
that are in the PCC subspsace.
Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
For cases where sys mapped CPC registers need to be accessed
frequently, it helps immensly to pre-map them rather than map
and unmap for each operation. e.g. case where feedback counters
are sys mem map registers.
Restructure cpc_read/write and the cpc_regs structure to allow
pre-mapping the system addresses and unmap them when the CPU exits.
Signed-off-by: Ashwin Chaugule <ashwin.chaugule@linaro.org>
Signed-off-by: Prashanth Prakash <pprakash@codeaurora.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Thus move sysfs_add_battery() after acpi_battery_get_state(), which doesn't
require the power_supply. Prevents possible hanged tasks if
acpi_battery_get_state() fails consistently (and takes a long time in doing
so) when called inside acpi_battery_add().
In this situation the battery module first calls sysfs_add_battery(),
which creates a power_supply, which spawns an async
power_supply_deferred_register_work() task, which shall try to hold the
parent battery device mutex (being already held) so this register work
is set up after device initialization. If initialization takes long enough
the thread will be eventually run and try to hold the mutex before
acpi_battery_add() had the chance to finish.
Eventually the 5 retries in acpi_battery_update_retry() fail, the error
state is propagated, and results in sysfs_remove_battery() being called
within the error handling paths of acpi_battery_add(), and the power_supply
tear down too.
This triggers a cancel_delayed_work_sync() of the deferred_register_work
task, which ends up in schedule(). The end result is that the deferred
task is blocked trying to acquire the parent device mutex, which is not
released because the thread doing initialization (and failure handling)
went to sleep awaiting for the deferred task to be cancelled.
The hanged tasks look like this:
INFO: task kworker/u8:0:6 blocked for more than 120 seconds.
...
Call Trace:
[<ffffffff815daec5>] schedule+0x35/0x80
[<ffffffff815dda3c>] schedule_timeout+0x1ec/0x250
[<ffffffff810a0572>] ? check_preempt_curr+0x52/0x90
[<ffffffff810a05c9>] ? ttwu_do_wakeup+0x19/0xe0
[<ffffffff815db915>] wait_for_common+0xc5/0x190
[<ffffffff810a1500>] ? wake_up_q+0x70/0x70
[<ffffffff815db9fd>] wait_for_completion+0x1d/0x20
[<ffffffff8108ffb1>] flush_work+0x111/0x1c0
[<ffffffff8108dfe0>] ? flush_workqueue_prep_pwqs+0x1a0/0x1a0
[<ffffffff810909af>] __cancel_work_timer+0x9f/0x1d0
[<ffffffff81090b13>] cancel_delayed_work_sync+0x13/0x20
[<ffffffff8147ac67>] power_supply_unregister+0x37/0xc0
[<ffffffffa058b03d>] sysfs_remove_battery+0x3d/0x52 [battery]
[<ffffffffa058bf3a>] acpi_battery_add+0x112/0x181 [battery]
[<ffffffff81366db6>] acpi_device_probe+0x54/0x19b
[<ffffffff81427e9c>] driver_probe_device+0x22c/0x440
[<ffffffff81428181>] __driver_attach+0xd1/0xf0
[<ffffffff814280b0>] ? driver_probe_device+0x440/0x440
[<ffffffff8142591c>] bus_for_each_dev+0x6c/0xc0
[<ffffffff8142758e>] driver_attach+0x1e/0x20
[<ffffffff81426fc3>] bus_add_driver+0x1c3/0x280
[<ffffffff81428b00>] driver_register+0x60/0xe0
[<ffffffff81366c80>] acpi_bus_register_driver+0x3b/0x43
[<ffffffffa0591040>] acpi_battery_init_async+0x1c/0x1e [battery]
[<ffffffff81099268>] async_run_entry_fn+0x48/0x150
[<ffffffff81090d09>] process_one_work+0x1e9/0x440
[<ffffffff81090fab>] worker_thread+0x4b/0x4f0
[<ffffffff81090f60>] ? process_one_work+0x440/0x440
[<ffffffff81096b58>] kthread+0xd8/0xf0
[<ffffffff815de97f>] ret_from_fork+0x1f/0x40
[<ffffffff81096a80>] ? kthread_worker_fn+0x180/0x180
INFO: task kworker/u8:4:282 blocked for more than 120 seconds.
...
Call Trace:
[<ffffffff810ad745>] ? put_prev_entity+0x35/0x8b0
[<ffffffff815daec5>] schedule+0x35/0x80
[<ffffffff815db14e>] schedule_preempt_disabled+0xe/0x10
[<ffffffff815dc533>] __mutex_lock_slowpath+0xb3/0x120
[<ffffffff815dc5bf>] mutex_lock+0x1f/0x30
[<ffffffff8147a59b>] power_supply_deferred_register_work+0x2b/0x50
[<ffffffff81090d09>] process_one_work+0x1e9/0x440
[<ffffffff81090fab>] worker_thread+0x4b/0x4f0
[<ffffffff81090f60>] ? process_one_work+0x440/0x440
[<ffffffff81090f60>] ? process_one_work+0x440/0x440
[<ffffffff81096b58>] kthread+0xd8/0xf0
[<ffffffff815de97f>] ret_from_fork+0x1f/0x40
[<ffffffff81096a80>] ? kthread_worker_fn+0x180/0x180
Making sysfs_add_battery() the last operation here means that the
power_supply won't be created yet when the acpi_add_battery() failure
handling happens, the deferred task won't even spawn, and
sysfs_remove_battery will just skip over the NULL battery->bat.
Signed-off-by: Carlos Garnacho <carlosg@gnome.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This patch enables the event freeze mode, flushing the EC event handling in
.suspend() callback. This feature is experimental, if it is bisected out to
be the cause of the real issues, please report the issues to the kernel
bugzilla for further root causing and improvement.
This mode eliminates useless _Qxx handling during the power saving
operations, thus can help to tune the power saving operations faster. Tests
show that this mode can efficiently block flooding _Qxx during the suspend
process and tune the speed of the suspend faster.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Tested-by: Todd E Brandt <todd.e.brandt@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In the original EC driver, though the event handling is not explicitly
stopped, the EC driver is actually not able to handle events during the
noirq stage as the EC driver is not prepared to handle the EC events in the
polling mode. So if there is no advance_transaction() triggered, the EC
driver couldn't notice the EC events.
However, do we actually need to handle EC events during suspend/resume
stage? EC events are mostly useless for the suspend/resume period (key
strokes and battery/thermal updates, etc.,), and the useful ones (lid
close, power/sleep button press) should have already been delivered to the
OSPM to trigger the power saving operations.
Thus this patch implements acpi_ec_disable_event() to be a reverse call of
acpi_ec_enable_event(), with which, the EC driver is able to stop handling
the EC events in a position before entering the noirq stage.
Since there are actually 2 choices for us:
1. implement event handling in polling mode;
2. stop event handling before entering noirq stage.
And this patch only implements the second choice using .suspend() callback.
Thus this is experimental (first choice is better? or different hook
position is better?). This patch finally keeps the old behavior by default
and prepares a boot parameter to enable this feature.
The differences of the event handling availability between the old behavior
(this patch is not applied) and the new behavior (this patch is applied)
are as follows:
!FreezeEvents FreezeEvents
before suspend Y Y
suspend before EC Y Y
suspend after EC Y N
suspend_late Y N
suspend_noirq Y (actually N) N
resume_noirq Y (actually N) N
resume_late Y (actually N) N
resume before EC Y (actually N) N
resume after EC Y Y
after resume Y Y
Where "actually N" means if there is no EC transactions, the EC driver
is actually not able to notice the pending events.
We can see that FreezeEvents is the only approach now can actually flush
the EC event handling with both query commands and _Qxx evaluations
flushed, other modes can only flush the EC event handling with only query
commands flushed, _Qxx evaluations occurred after stopping the EC driver
may end up failure due to the failure of the EC transaction carried out in
the _Qxx control methods.
We also can see that this feature should be able to trigger some platform
notifications later than resuming other drivers.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Tested-by: Todd E Brandt <todd.e.brandt@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This patch makes 2 changes:
1. Restore old behavior
Originally, EC driver stops handling both events and transactions in
acpi_ec_block_transactions(), and restarts to handle transactions in
acpi_ec_unblock_transactions_early(), restarts to handle both events and
transactions in acpi_ec_unblock_transactions().
While currently, EC driver still stops handling both events and
transactions in acpi_ec_block_transactions(), but restarts to handle both
events and transactions in acpi_ec_unblock_transactions_early().
This patch tries to restore the old behavior by dropping
__acpi_ec_enable_event() from acpi_unblock_transactions_early().
2. Improve old behavior
However this still cannot fix the real issue as both of the
acpi_ec_unblock_xxx() functions are invoked in the noirq stage. Since the
EC driver actually doesn't implement the event handling in the polling
mode, re-enabling the event handling too early in the noirq stage could
result in the problem that if there is no triggering source causing
advance_transaction() to be invoked, pending SCI_EVT cannot be detected by
the EC driver and _Qxx cannot be triggered.
It actually makes sense to restart the event handling in any point during
resuming after the noirq stage. Just like the boot stage where the event
handling is enabled in .add(), this patch further moves
acpi_ec_enable_event() to .resume(). After doing that, the following 2
functions can be combined:
acpi_ec_unblock_transactions_early()/acpi_ec_unblock_transactions().
The differences of the event handling availability between the old behavior
(this patch isn't applied) and the new behavior (this patch is applied) are
as follows:
!Applied Applied
before suspend Y Y
suspend before EC Y Y
suspend after EC Y Y
suspend_late Y Y
suspend_noirq Y (actually N) Y (actually N)
resume_noirq Y (actually N) Y (actually N)
resume_late Y (actually N) Y (actually N)
resume before EC Y (actually N) Y (actually N)
resume after EC Y (actually N) Y
after resume Y (actually N) Y
Where "actually N" means if there is no triggering source, the EC driver
is actually not able to notice the pending SCI_EVT occurred in the noirq
stage. So we can clearly see that this patch has improved the situation.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Tested-by: Todd E Brandt <todd.e.brandt@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
After enabling the EC event handling, Linux is still in the noirq stage, if
there is no triggering source (EC transaction, GPE STS status),
advance_transaction() will not be invoked and SCI_EVT cannot be detected.
This patch adds one more triggering source after enabling the EC event
handling to poll the pending SCI_EVT.
Known issues:
1. Still no SCI_EVT triggering source
There could still be no SCI_EVT triggering source after handling the
first SCI_EVT (polled by this patch if any). Because after handling the
first SCI_EVT, Linux could still be in noirq stage and there could still
be no further triggering source in this stage. Then the second SCI_EVT
indicated during this stage still cannot be detected by the EC driver.
With this improvement applied, it is then possible to move
acpi_ec_enable_event() out of the noirq stage to fix this issue (if the
first SCI_EVT is handled out of the noirq stage, the follow-up SCI_EVTs
should be able to trigger IRQs).
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Tested-by: Todd E Brandt <todd.e.brandt@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
There is a hidden logic in the EC driver:
1. During boot, EC_FLAGS_QUERY_PENDING is responsible for blocking event
handling;
2. During suspend, EC_FLAGS_STARTED is responsible for blocking event
handling.
This patch uses a new EC_FLAGS_QUERY_ENABLED flag to make this hidden
logic explicit and have code cleaned up. No functional change.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Tested-by: Todd E Brandt <todd.e.brandt@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Following the fwnode of a device is currently a one-way road: We provide
ACPI_COMPANION() to obtain the fwnode but there's no (public) method to
do the reverse. Granted, there may be multiple physical_nodes, but often
the first one in the list is sufficient.
A handy function to obtain it was introduced with commit 3b95bd1605
("ACPI: introduce a function to find the first physical device"), but
currently it's only available internally.
We're about to add an EFI Device Path parser which needs this function.
Consider the following device path: ACPI(PNP0A03,0)/PCI(28,2)/PCI(0,0)
The PCI root is encoded as an ACPI device in the path, so the parser
has to find the corresponding ACPI device, then find its physical node,
find the PCI bridge in slot 1c (decimal 28), function 2 below it and
finally find the PCI device in slot 0, function 0.
To this end, make acpi_get_first_physical_node() public.
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Per "ACPI 6.1 Section 9.20.3" NVDIMM devices, children of the ACPI0012
NVDIMM Root device, can receive health event notifications.
Given that these devices are precluded from registering a notification
handler via acpi_driver.acpi_device_ops (due to no _HID), we use
acpi_install_notify_handler() directly. The registered handler,
acpi_nvdimm_notify(), triggers a poll(2) event on the nmemX/nfit/flags
sysfs attribute when a health event notification is received.
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Toshi Kani <toshi.kani@hpe.com>
Reviewed-by: Vishal Verma <vishal.l.verma@intel.com>
Acked-by: Rafael J. Wysocki <rafael@kernel.org>
Reviewed-by: Toshi Kani <toshi.kani@hpe.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
