* acpi-processor:
ACPI / cpuidle: Common callback routine for entering states
ACPI / cpuidle: Merge acpi_idle_enter_c1() and acpi_idle_enter_simple()
ACPI / cpuidle: Drop flags.bm_check tests from acpi_idle_enter_bm()
ACPI / cpuidle: Clean up white space in a switch statement
ACPI / cpuidle: Drop irrelevant comment from acpi_idle_enter_simple()
ACPI / cpuidle: Clean up fallback to C1 checks
ACPI / cpuidle: Drop unnecessary calls from ->enter callback routines
ACPI / cpuidle: Drop unnecessary calls from acpi_idle_do_entry()
* acpi-doc:
MAINTAINERS / ACPI: add the necessary '/' according to entry rules
ACPI / Documentation: add a missing '='
* acpi-pm:
ACPI / sleep: mark acpi_sleep_dmi_check() __init
* acpi-pcc:
ACPI / PCC: Use pr_debug() for debug messages in pcc_init()
* acpi-tables:
ACPI / table: remove duplicate NULL check for the handler of acpi_table_parse()
* acpi-video:
ACPI / video: Add disable_native_backlight quirk for Samsung 510R
ACPI / video: Add disable_native_backlight quirk for Samsung 730U3E/740U3E
* acpi-soc:
ACPI: add AMD ACPI2Platform device support for x86 system
ACPI / LPSS: Remove non-existing clock control from Intel Lynxpoint I2C
ACPI / LPSS: check the result of ioremap()
* acpica:
ACPICA: Events: Enable APIs to allow interrupt/polling adaptive request based GPE handling model
ACPICA: Events: Introduce acpi_set_gpe()/acpi_finish_gpe() to reduce divergences
ACPICA: Events: Introduce ACPI_GPE_DISPATCH_RAW_HANDLER to fix 2 issues for the current GPE APIs
ACPICA: Update version to 20150204
ACPICA: Update Copyright headers to 2015
ACPICA: Hardware: Cast GPE enable_mask before storing
ACPICA: Events: Cleanup GPE dispatcher type obtaining code
ACPICA: Events: Cleanup to move acpi_gbl_global_event_handler invocation out of acpi_ev_gpe_dispatch()
ACPICA: Events: Cleanup of resetting the GPE handler to NULL before removing
ACPICA: Events: Fix uninitialized variable
ACPICA: Events: Remove acpi_ev_valid_gpe_event() due to current restriction
ACPICA: Events: Remove duplicated sanity check in acpi_ev_enable_gpe()
ACPICA: Events: Back port "ACPICA: Save current masks of enabled GPEs after enable register writes"
ACPICA: Resources: Provide common part for struct acpi_resource_address structures.
ACPI: Introduce acpi_unload_parent_table() usages in Linux kernel
ACPICA: take ACPI_MTX_INTERPRETER in acpi_unload_table_id()
Backlight control through the native intel interface does not work properly
on the Samsung 510R, where as using the acpi_video interface does work, add
a quirk for this.
Link: https://bugzilla.redhat.com/show_bug.cgi?id=1186097
Cc: All applicable <stable@vger.kernel.org>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This patch enhances debugging with the GPE reference count messages added.
No functional changes.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This patch implementes the QR_EC flushing support.
Grace periods are implemented from the detection of an SCI_EVT to the
submission/completion of the QR_EC transaction. During this period, all
EC command transactions are allowed to be submitted.
Note that query periods and event periods are intentionally distiguished to
allow further improvements.
1. Query period: from the detection of an SCI_EVT to the sumission of the
QR_EC command. This period is used for storming prevention, as currently
QR_EC is deferred to a work queue rather than directly issued from the
IRQ context even there is no other transactions pending, so malicous
SCI_EVT GPE can act like "level triggered" to trigger a GPE storm. We
need to be prepared for this. And in the future, we may change it to be
a part of the advance_transaction() where we will try QR_EC submission
in appropriate positions to avoid such GPE storming.
2. Event period: from the detection of an SCI_EVT to the completion of the
QR_EC command. We may extend it to the completion of _Qxx evaluation.
This is actually a grace period for event flushing, but we only flush
queries due to the reason stated in known issue 1. That's also why we
use EC_FLAGS_EVENT_xxx. During this period, QR_EC transactions need to
pass the flushable submission check.
In this patch, the following flags are implemented:
1. EC_FLAGS_EVENT_ENABLED: this is derived from the old
EC_FLAGS_QUERY_PENDING flag which can block SCI_EVT handlings.
With this flag, the logics implemented by the original flag are
extended:
1. Old logic: unless both of the flags are set, the event poller will
not be scheduled, and
2. New logic: as soon as both of the flags are set, the evet poller will
be scheduled.
2. EC_FLAGS_EVENT_DETECTED: this is also derived from the old
EC_FLAGS_QUERY_PENDING flag which can block SCI_EVT detection. It thus
can be used to indicate the storming prevention period for query
submission.
acpi_ec_submit_request()/acpi_ec_complete_request() are invoked to
implement this period so that acpi_set_gpe() can be invoked under the
"reference count > 0" condition.
3. EC_FLAGS_EVENT_PENDING: this is newly added to indicate the grace period
for event flushing (query flushing for now).
acpi_ec_submit_request()/acpi_ec_complete_request() are invoked to
implement this period so that the flushing process can wait until the
event handling (query transaction for now) to be completed.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=82611
Link: https://bugzilla.kernel.org/show_bug.cgi?id=77431
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Tested-by: Ortwin Glück <odi@odi.ch>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This patch refines EC command storm prevention support.
Current command storming code is wrong, when the storming condition is
detected, it only flags the condition without doing anything for the
current command but performing storming prevention for the follow-up
commands. So:
1. The first command which suffers from the storming still suffers from
storming.
2. The follow-up commands which may not suffer from the storming are
unconditionally forced into the storming prevention mode.
Ideally, we should only enable storm prevention immediately after detection
for the current command so that the next command can try the
power/performance efficient interrupt mode again.
This patch improves the command storm prevention by disabling GPE right
after the detection and re-enabling it right before completing the command
transaction using the GPE storming prevention APIs. This thus deploys the
following GPE handling model:
1. acpi_enable_gpe()/acpi_disable_gpe() for reference count changes:
This set of APIs are used for EC usage reference counting.
2. acpi_set_gpe(ACPI_GPE_ENABLE)/acpi_set_gpe(ACPI_GPE_DISABLE):
This set of APIs are used for preventing GPE storm. They must be invoked
when the reference count > 0.
Note that as the storming prevention should always happen when there is
an outstanding request, or GPE enabling value will be messed up by the
races. This patch also adds BUG_ON() to enforces this rule to prevent
future bugs.
The msleep(1) used after completing a transaction is useless now as this
sounds like a guard time only useful for platforms that need the
EC_FLAGS_MSI quirks while we have fixed GPE race issues using the previous
raw handler mode enabling. It is kept to avoid regressions. A seperate
patch which deletes EC_FLAGS_MSI quirks should take care of deleting it.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This patch implements the EC command flushing support.
During the grace period indicated by EC_FLAGS_STARTED and EC_FLAGS_STOPPED,
all submitted EC command transactions can be completed and new submissions
are prevented before suspending so that the EC hardware can be ensured to
be in the idle state when the system is resumed.
There is a good indicator for flush support:
All acpi_ec_submit_request() is invoked after checking driver state with
acpi_ec_started() except the first one. This means all code paths can be
flushed as fast as possible by discarding the requests occurred after the
flush operation. The reference increased for such kind of code path is
wrapped by acpi_ec_submit_flushable_request().
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Tested-by: Ortwin Glück <odi@odi.ch>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
By using the 2 flags, we can indicate an inter-mediate state where the
current transactions should be completed while the new transactions should
be dropped.
The comparison of the old flag and the new flags:
Old New
about to set BLOCKED STOPPED set / STARTED set
BLOCKED set STOPPED clear / STARTED clear
BLOCKED clear STOPPED clear / STARTED set
A new period can be indicated by the 2 flags. The new period is between the
point where we are about to set BLOCKED and the point when the BLOCKED is
set. The new flags facilitate us with acpi_ec_started() check to allow the
EC transaction to be submitted during the new period. This period thus can
be used as a grace period for the EC transaction flushing.
The only functional change after applying this patch is:
1. The GPE enabling/disabling is protected by the EC specific lock. We can
do this because of recent ACPICA GPE API enhancement. This is reasonable
as the GPE disabling/enabling state should only be determined by the EC
driver's state machine which is protected by the EC spinlock.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Tested-by: Ortwin Glück <odi@odi.ch>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This new feature is to interpret AMD specific ACPI device to
platform device such as I2C, UART, GPIO found on AMD CZ and
later chipsets. It based on example intel LPSS. Now, it can
support AMD I2C, UART and GPIO.
Signed-off-by: Ken Xue <Ken.Xue@amd.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In acpi_table_parse(), pointer of the table to pass to handler() is
checked before handler() called, so remove all the duplicate NULL
check in the handler function.
CC: Tony Luck <tony.luck@intel.com>
CC: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Hanjun Guo <hanjun.guo@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The bug fixes around GPE races have been done to the EC driver by the
previous commits. This patch increases the revision to 3 to indicate the
behavior differences between the old and the new drivers. The
copyright/authorship notices are also updated.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Timeout in the ec_poll() doesn't refer to the last register access time. It
thus can win the competition against the acpi_ec_gpe_handler() if a
transaction takes longer than 1ms but individual register accesses are less
than 1ms. In some cases, it can make the following silicon bug easier to
be triggered:
GPE EN is not wired to the GPE trigger line, so when GPE STS is already
set when 1 is written to GPE EN, no GPE can be triggered.
This patch adds register access timestamp reference support for ec_poll()
to reduce the number of ec_poll() invocations.
Reported-by: Venkat Raghavulu <venkat.raghavulu@intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This patch switches EC driver into ACPI_GPE_DISPATCH_RAW_HANDLER mode where
the GPE lock is not held for acpi_ec_gpe_handler() and the ACPICA internal
GPE enabling/disabling/clearing operations are bypassed so that further
improvements are possible with the GPE APIs.
There are 2 strong reasons for deploying raw GPE handler mode in the EC
driver:
1. Some hardware logics can control their interrupts via their own
registers, so their interrupts can be disabled/enabled/acknowledged
without using the super IRQ controller provided functions. While there
is no mean (EC commands) for the EC driver to achieve this.
2. During suspending, the EC driver is still working for a while to
complete the platform firmware provided functionailities using ec_poll()
after all GPEs are disabled (see acpi_ec_block_transactions()), which
means the EC driver will drive the EC GPE out of the GPE core's control.
Without deploying the raw GPE handler mode, we can see many races between
the EC driver and the GPE core due to the above restrictions:
1. There is a race condition due to ACPICA internal GPE
disabling/clearing/enabling logics in acpi_ev_gpe_dispatch():
Orignally EC GPE is disabled (EN=0), cleared (STS=0) before invoking a
GPE handler and re-enabled (EN=1) after invoking a GPE handler in
acpi_ev_gpe_dispatch(). When re-enabling appears, GPE may be flagged
(STS=1).
=================================================================
(event pending A)
=================================================================
acpi_ev_gpe_dispatch() ec_poll()
EN=0
STS=0
acpi_ec_gpe_handler()
*****************************************************************
(event handling A)
Lock(EC)
advance_transaction()
EC_SC read
=================================================================
(event pending B)
=================================================================
EC_SC handled
Unlock(EC)
*****************************************************************
*****************************************************************
(event handling B)
Lock(EC)
advance_transaction()
EC_SC read
=================================================================
(event pending C)
=================================================================
EC_SC handled
Unlock(EC)
*****************************************************************
EN=1
This race condition is the root cause of different issues on different
silicon variations.
A. Silicon variation A:
On some platforms, GPE will be triggered due to "writing 1 to EN when
STS=1". This is because both EN and STS lines are wired to the GPE
trigger line.
1. Issue 1:
We can see no-op acpi_ec_gpe_handler() invoked on such platforms.
This is because:
a. event pending B: An event can arrive after ACPICA's GPE
clearing performed in acpi_ev_gpe_dispatch(), this event may
fail to be detected by EC_SC read that is performed before its
arrival;
b. event handling B: The event can be handled in ec_poll() because
EC lock is released after acpi_ec_gpe_handler() invocation;
c. There is no code in ec_poll() to clear STS but the GPE can
still be triggered by the EN=1 write performed in
acpi_ev_finish_gpe(), this leads to a no-op EC GPE handler
invocation;
d. As no-op GPE handler invocations are counted by the EC driver
to trigger the command storming conditions, the wrong no-op
GPE handler invocations thus can easily trigger wrong command
storming conditions.
Note 1:
If we removed GPE disabling/enabling code from
acpi_ev_gpe_dispatch(), we could still see no-op GPE handlers
triggered by the event arriving after the GPE clearing and before
the GPE handling on both silicon variation A and B. This can only
occur if the CPU is very slow (timing slice between STS=0 write
and EC_SC read should be short enough before hardware sets another
GPE indication). Thus this is very rare and is not what we need to
fix.
B. Silicon variation B:
On other platforms, GPE may not be triggered due to "writing 1 to EN
when STS=1". This is because only STS line is wired to the GPE
trigger line.
2. Issue 2:
We can see GPE loss on such platforms. This is because:
a. event pending B vs. event handling A: An event can arrive after
ACPICA's GPE handling performed in acpi_ev_gpe_dispatch(), or
event pending C vs. event handling B: An event can arrive after
Linux's GPE handling performed in ec_poll(),
these events may fail to be detected by EC_SC read that is
performed before their arrival;
b. The GPE cannot be triggered by EN=1 write performed in
acpi_ev_finish_gpe();
c. If no polling mechanism is implemented in the driver for the
pending event (for example, SCI_EVT), this event is lost due to
no GPE being triggered.
Note 2:
On most platforms, there might be another rule that GPE may not be
triggered due to "writing 1 to STS when STS=1 and EN=1".
Then on silicon variation B, an even worse case is if the issue 2
event loss happens, further events may never trigger GPE again on
such platforms due to being blocked by the current STS=1. Unless
someone clears STS, all events have to be polled.
2. There is a race condition due to lacking in GPE status checking in EC
driver:
Originally, GPE status is checked in ACPICA core but not checked in
the GPE handler. Thus since the status checking and handling is not
locked, it can be interrupted by another handling path.
=================================================================
(event pending A)
=================================================================
acpi_ev_gpe_detect() ec_poll()
if (EN==1 && STS==1)
*****************************************************************
(event handling A)
Lock(EC)
advance_transaction()
EC_SC read
EC_SC handled
Unlock(EC)
*****************************************************************
acpi_ev_gpe_dispatch()
EN=0
STS=0
acpi_ec_gpe_handler()
*****************************************************************
(event handling B)
Lock(EC)
advance_transaction()
EC_SC read
Unlock(EC)
*****************************************************************
3. Issue 3:
We can see no-op acpi_ec_gpe_handler() invoked on both silicon
variation A and B. This is because:
a. event pending A: An event can arrive to trigger an EC GPE and
ACPICA checks it and is about to invoke the EC GPE handler;
b. event handling A: The event can be handled in ec_poll() because
EC lock is not held after the GPE status checking;
c. event handling B: Then when the EC GPE handler is invoked, it
becomes a no-op GPE handler invocation.
d. As no-op GPE handler invocations are counted by the EC driver
to trigger the command storming conditions, the wrong no-op
GPE handler invocations thus can easily trigger wrong command
storming conditions.
Note 3:
This no-op GPE handler invocation is rare because the time between
the IRQ arrival and the acpi_ec_gpe_handler() invocation is less than
the timeout value waited in ec_poll(). So most of the no-op GPE
handler invocations are caused by the reason described in issue 1.
3. There is a race condition due to ACPICA internal GPE clearing logic in
acpi_enable_gpe():
During runtime, acpi_enable_gpe() can be invoked by the EC storming
prevention code. When it is invoked, GPE may be flagged (STS=1).
=================================================================
(event pending A)
=================================================================
acpi_ev_gpe_dispatch() acpi_ec_transaction()
EN=0
STS=0
acpi_ec_gpe_handler()
*****************************************************************
(event handling A)
Lock(EC)
advance_transaction()
EC_SC read
EC_SC handled
Unlock(EC)
*****************************************************************
EN=1 ?
Lock(EC)
Unlock(EC)
=================================================================
(event pending B)
=================================================================
acpi_enable_gpe()
STS=0
EN=1
4. Issue 4:
We can see GPE loss on both silicon variation A and B platforms.
This is because:
a. event pending B: An event can arrive right before ACPICA's GPE
clearing performed in acpi_enable_gpe();
b. If the GPE is cleared when GPE is disabled, then EN=1 write in
acpi_enable_gpe() cannot trigger this GPE;
c. If no polling mechanism is implemented in the driver for this
event (for example, SCI_EVT), this event is lost due to no GPE
being triggered.
Note 4:
Currently we don't have this issue, but after we switch the EC
driver into ACPI_GPE_DISPATCH_RAW_HANDLER mode, we need to take care
of handling this because the EN=1 write in acpi_ev_gpe_dispatch()
will be abandoned.
There might be more race issues for the current GPE handler usages. This is
because the EC IRQ's enabling/disabling/checking/clearing/handling
operations should be locked by a single lock that is under the EC driver's
control to achieve the serialization. Which means we need to invoke GPE
APIs with EC driver's lock held and all ACPICA internal GPE operations
related to the GPE handler should be abandoned. Invoking GPE APIs inside of
the EC driver lock and bypassing ACPICA internal GPE operations requires
the ACPI_GPE_DISPATCH_RAW_HANDLER mode where the same lock used by the APIs
are released prior than invoking the handlers. Otherwise, we can see dead
locks due to circular locking dependencies (see Reference below).
This patch then switches the EC driver into the
ACPI_GPE_DISPATCH_RAW_HANDLER mode so that it can perform correct GPE
operations using the GPE APIs:
1. Bypasses EN modifications performed in acpi_ev_gpe_dispatch() by
using acpi_install_gpe_raw_handler() and invoking all GPE APIs with EC
spin lock held. This can fix issue 1 as it makes a non frequent GPE
enabling/disabling environment.
2. Bypasses STS clearing performed in acpi_enable_gpe() by replacing
acpi_enable_gpe()/acpi_disable_gpe() with acpi_set_gpe(). This can fix
issue 4. And this can also help to fix issue 1 as it makes a no sudden
GPE clearing environment when GPE is frequently enabled/disabled.
3. Ensures STS acknowledged before handling by invoking acpi_clear_gpe()
in advance_transaction(). This can finally fix issue 1 even in a
frequent GPE enabling/disabling environment. And this can also finally
fix issue 3 when issue 2 is fixed.
Note 3:
GPE clearing is edge triggered W1C, which means we can clear it right
before handling it. Since all EC GPE indications are handled in
advance_transaction() by previous commits, we can now move GPE clearing
into it to implement the correct GPE clearing.
Note 4:
We can use acpi_set_gpe() which is not shared GPE safer instead of
acpi_enable_gpe()/acpi_disable_gpe() because EC GPE is not shared by
other hardware, which is mentioned in the ACPI specification 5.0, 12.6
Interrupt Model: "OSPM driver treats this as an edge event (the EC SCI
cannot be shared)". So we can stop using shared GPE safer APIs
acpi_enable_gpe()/acpi_disable_gpe() in the EC driver. Otherwise
cleanups need to be made in acpi_ev_enable_gpe() to bypass the GPE
clearing logic before keeping acpi_enable_gpe().
This patch also invokes advance_transaction() when GPE is re-enabled in the
task context which:
1. Ensures EN=1 can trigger GPE by checking and handling EC status register
right after EN=1 writes. This can fix issue 2.
After applying this patch, without frequent GPE enablings considered:
=================================================================
(event pending A)
=================================================================
acpi_ec_gpe_handler() ec_poll()
*****************************************************************
(event handling A)
Lock(EC)
advance_transaction()
if STS==1
STS=0
EC_SC read
=================================================================
(event pending B)
=================================================================
EC_SC handled
Unlock(EC)
*****************************************************************
*****************************************************************
(event handling B)
Lock(EC)
advance_transaction()
if STS==1
STS=0
EC_SC read
=================================================================
(event pending C)
=================================================================
EC_SC handled
Unlock(EC)
*****************************************************************
The event pending for issue 1 (event pending B) can arrive as a next GPE
due to the previous IRQ context STS=0 write. And if it is handled by
ec_poll() (event handling B), as it is also acknowledged by ec_poll(), the
event pending for issue 2 (event pending C) can properly arrive as a next
GPE after the task context STS=0 write. So no GPE will be lost and never
triggered due to GPE clearing performed in the wrong position. And since
all GPE handling is performed after a locked GPE status checking, we can
hardly see no-op GPE handler invocations due to issue 1 and 3. We may still
see no-op GPE handler invocations due to "Note 1", but as it is inevitable,
it needn't be fixed.
After applying this patch, with frequent GPE enablings considered:
=================================================================
(event pending A)
=================================================================
acpi_ec_gpe_handler() acpi_ec_transaction()
*****************************************************************
(event handling A)
Lock(EC)
advance_transaction()
if STS==1
STS=0
EC_SC read
=================================================================
(event pending B)
=================================================================
EC_SC handled
Unlock(EC)
*****************************************************************
*****************************************************************
(event handling B)
Lock(EC)
EN=1
if STS==1
advance_transaction()
if STS==1
STS=0
EC_SC read
=================================================================
(event pending C)
=================================================================
EC_SC handled
Unlock(EC)
*****************************************************************
The event pending for issue 2 can be manually handled by
advance_transaction(). And after the STS=0 write performed in the manual
triggered advance_transaction(), GPE can always arrive. So no GPE will be
lost due to frequent GPE disabling/enabling performed in the driver like
issue 4.
Note 5:
It's ideally when EN=1 write occurred, an IRQ thread should be woken up to
handle the GPE when the GPE was raised. But this requires the IRQ thread to
contain the poller code for all EC GPE indications, while currently some of
the indications are handled in the user tasks. It then is very hard for the
code to determine whether a user task should be invoked or the poller work
item should be scheduled. So we have to invoke advance_transaction()
directly now and it leaves us such a restriction for the GPE re-enabling:
it must be performed in the task context to avoid starving the GPEs.
As a conclusion: we can see the EC GPE is always handled in serial after
deploying the raw GPE handler mode:
Lock(EC)
if (STS==1)
STS=0
EC_SC read
EC_SC handled
Unlock(EC)
The EC driver specific lock is responsible to make the EC GPE handling
processes serialized so that EC can handle its GPE from both IRQ and task
contexts and the next IRQ can be ensured to arrive after this process.
Note 6:
We have many EC_FLAGS_MSI qurik users in the current driver. They all seem
to be suffering from unexpected GPE triggering source lost. And they are
false root caused to a timing issue. Since EC communication protocol has
already flow control defined, timing shouldn't be the root cause, while
this fix might be fixing the root cause of the old bugs.
Link: https://lkml.org/lkml/2014/11/4/974
Link: https://lkml.org/lkml/2014/11/18/316
Link: https://www.spinics.net/lists/linux-acpi/msg54340.html
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPICA commit da9a83e1a845f2d7332bdbc0632466b2595e5424
For acpi_set_gpe()/acpi_enable_gpe(), our target is to purify them to be APIs
that can be used for various GPE handling models, so we need them to be
pure GPE enabling APIs. GPE enabling/disabling has 2 use cases:
1. Driver may permanently enable/disable GPEs according to the usage
counts.
1. When upper layers (the users of the driver) submit requests to the
driver, it means they care about the underlying hardware. GPE need
to be enabled for the first request submission and disabled for the
last request completion.
2. When the GPE is shared between 2+ silicon logics. GPE need to be
enabled for either silicon logic's driver and disabled when all of
the drivers are not started.
For these cases, acpi_enable_gpe()/acpi_disable_gpe() should be used. When
the usage count is increased from 0 to 1, the GPE is enabled and it is
disabled when the usage count is decrased from 1 to 0.
2. Driver may temporarily disables the GPE to enter an GPE polling mode and
wants to re-enable it later.
1. Prevent GPE storming: when a driver cannot fully solve the condition
that triggered the GPE in the GPE context, in order not to trigger
GPE storm, driver has to disable GPE to switch into the polling mode
and re-enables it in the non interrupt context after the storming
condition is cleared.
2. Meet throughput requirement: some IO drivers need to poll hardware
again and again until nothing indicated instead of just handling once
for one interruption, this need to be done in the polling mode or the
IO flood may prevent the GPE handler from returning.
3. Meet realtime requirement: in order not to block CPU to handle higher
realtime prioritized GPEs, lower priority GPEs can be handled in the
polling mode.
For these cases, acpi_set_gpe() should be used to switch to/from the
polling mode.
This patch adds unconditional GPE enabling support into acpi_set_gpe() so
that this API can be used by the drivers to switch back from the GPE
polling mode unconditionally.
Originally this function includes GPE clearing logic in it.
First, the GPE clearing is typically used in the GPE handling code to:
1. Acknowledge the GPE when we know there is an edge triggered GPE raised
and is about to handle it, otherwise the unexpected clearing may lead to
a GPE loss;
2. Issue actions after we have handled a level triggered GPE, otherwise
the unexpected clearing may trigger unwanted OSPM actions to the
hardware (for example, clocking in out-dated write FIFO data).
Thus the GPE clearing is not suitable to be used in the GPE enabling APIs.
Second, the combination of acknowledging and enabling may also not be
expected by the hardware drivers. For GPE clearing, we have a seperate API
acpi_clear_gpe(). There are cases drivers do want the 2 operations to be
split. So splitting these 2 operations could facilitates drivers the
maximum possibilities to achieve success. For a combined one, we already
have acpi_finish_gpe() ready to be invoked.
Given the fact that drivers should complete all outstanding requests before
putting themselves into the sleep states, as this API is executed for
outstanding requests, it should also have nothing to do with the
"RUN"/"WAKE" distinguishing. That's why the acpi_set_gpe(ACPI_GPE_ENABLE)
should not be implemented by acpi_hw_low_set_gpe(ACPI_GPE_CONDITIONAL_ENABLE).
This patch thus converts acpi_set_gpe(ACPI_GPE_ENABLE) into
acpi_hw_low_set_gpe(ACPI_GPE_ENABLE) to achieve a seperate GPE enabling API.
Drivers then are encouraged to use this API when they need to switch
to/from the GPE polling mode.
Note that the acpi_set_gpe()/acpi_finish_gpe() should be first introduced to
Linux using a divergence reduction patch before sending a linuxized version
of this patch. Lv Zheng.
Link: https://github.com/acpica/acpica/commit/da9a83e1
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: David E. Box <david.e.box@linux.intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This can help to reduce source code differences between Linux and ACPICA
upstream. Further driver cleanups also require these APIs to eliminate GPE
storms.
1. acpi_set_gpe(): An API that driver should invoke in the case it wants
to disable/enable IRQ without honoring the reference
count implemented in the acpi_disable_gpe() and
acpi_enable_gpe(). Note that this API should only be
invoked inside a acpi_enable_gpe()/acpi_disable_gpe()
pair.
2. acpi_finish_gpe(): Drivers returned ACPI_REENABLE_GPE unset from the
GPE handler should use this API instead of
invoking acpi_set_gpe()/acpi_enable_gpe() to
re-enable the GPE.
The GPE APIs can be invoked inside of a GPE handler or in the task context
with a driver provided lock held. This driver provided lock is safe to be
held in the GPE handler by the driver.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPICA commit 199cad16530a45aea2bec98e528866e20c5927e1
Since whether the GPE should be disabled/enabled/cleared should only be
determined by the GPE driver's state machine:
1. GPE should be disabled if the driver wants to switch to the GPE polling
mode when a GPE storm condition is indicated and should be enabled if
the driver wants to switch back to the GPE interrupt mode when all of
the storm conditions are cleared. The conditions should be protected by
the driver's specific lock.
2. GPE should be enabled if the driver has accepted more than one request
and should be disabled if the driver has completed all of the requests.
The request count should be protected by the driver's specific lock.
3. GPE should be cleared either when the driver is about to handle an edge
triggered GPE or when the driver has completed to handle a level
triggered GPE. The handling code should be protected by the driver's
specific lock.
Thus the GPE enabling/disabling/clearing operations are likely to be
performed with the driver's specific lock held while we currently cannot do
this. This is because:
1. We have the acpi_gbl_gpe_lock held before invoking the GPE driver's
handler. Driver's specific lock is likely to be held inside of the
handler, thus we can see some dead lock issues due to the reversed
locking order or recursive locking. In order to solve such dead lock
issues, we need to unlock the acpi_gbl_gpe_lock before invoking the
handler. BZ 1100.
2. Since GPE disabling/enabling/clearing should be determined by the GPE
driver's state machine, we shouldn't perform such operations inside of
ACPICA for a GPE handler to mess up the driver's state machine. BZ 1101.
Originally this patch includes a logic to flush GPE handlers, it is dropped
due to the following reasons:
1. This is a different issue;
2. Linux OSL has fixed this by flushing SCI in acpi_os_wait_events_complete().
We will pick up this topic when the Linux OSL fix turns out to be not
sufficient.
Note that currently the internal operations and the acpi_gbl_gpe_lock are
also used by ACPI_GPE_DISPATCH_METHOD and ACPI_GPE_DISPATCH_NOTIFY. In
order not to introduce regressions, we add one
ACPI_GPE_DISPATCH_RAW_HANDLER type to be distiguished from
ACPI_GPE_DISPATCH_HANDLER. For which the acpi_gbl_gpe_lock is unlocked before
invoking the GPE handler and the internal enabling/disabling operations are
bypassed to allow drivers to perform them at a proper position using the
GPE APIs and ACPI_GPE_DISPATCH_RAW_HANDLER users should invoke acpi_set_gpe()
instead of acpi_enable_gpe()/acpi_disable_gpe() to bypass the internal GPE
clearing code in acpi_enable_gpe(). Lv Zheng.
Known issues:
1. Edge-triggered GPE lost for frequent enablings
On some buggy silicon platforms, GPE enable line may not be directly
wired to the GPE trigger line. In that case, when GPE enabling is
frequently performed for edge-triggered GPEs, GPE status may stay set
without being triggered.
This patch may maginify this problem as it allows GPE enabling to be
parallel performed during the process the GPEs are handled.
This is an existing issue, because:
1. For task context:
Current ACPI_GPE_DISPATCH_METHOD practices have proven that this
isn't a real issue - we can re-enable edge-triggered GPE in a work
queue where the GPE status bit might already be set.
2. For IRQ context:
This can even happen when the GPE enabling occurs before returning
from the GPE handler and after unlocking the GPE lock.
Thus currently no code is included to protect this.
Link: https://github.com/acpica/acpica/commit/199cad16
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 8990e73ab2aa15d6a0068b860ab54feff25bee36
Link: https://github.com/acpica/acpica/commit/8990e73a
Signed-off-by: David E. Box <david.e.box@linux.intel.com>
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>
ACPICA commit 490ec7f7839bf7ee5e8710a34d1d1a78d54a49b6
In function acpi_hw_low_set_gpe(), cast enable_mask to u8 before
storing. The mask was read from a 32 bit register but is an 8 bit
value. Fixes Visual Studio compiler warning.
Link: https://github.com/acpica/acpica/commit/490ec7f7
Signed-off-by: David E. Box <david.e.box@linux.intel.com>
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>
ACPICA commit 7926d5ca9452c87f866938dcea8f12e1efb58f89
There is an issue in acpi_install_gpe_handler() and acpi_remove_gpe_handler().
The code to obtain the GPE dispatcher type from the Handler->original_flags
is wrong:
if (((Handler->original_flags & ACPI_GPE_DISPATCH_METHOD) ||
(Handler->original_flags & ACPI_GPE_DISPATCH_NOTIFY)) &&
ACPI_GPE_DISPATCH_NOTIFY is 0x03 and ACPI_GPE_DISPATCH_METHOD is 0x02, thus
this statement is TRUE for the following dispatcher types:
0x01 (ACPI_GPE_DISPATCH_HANDLER): not expected
0x02 (ACPI_GPE_DISPATCH_METHOD): expected
0x03 (ACPI_GPE_DISPATCH_NOTIFY): expected
There is no functional issue due to this because Handler->original_flags is
only set in acpi_install_gpe_handler(), and an earlier checker has excluded
the ACPI_GPE_DISPATCH_HANDLER:
if ((gpe_event_info->Flags & ACPI_GPE_DISPATCH_MASK) ==
ACPI_GPE_DISPATCH_HANDLER)
{
Status = AE_ALREADY_EXISTS;
goto free_and_exit;
}
...
Handler->original_flags = (u8) (gpe_event_info->Flags &
(ACPI_GPE_XRUPT_TYPE_MASK | ACPI_GPE_DISPATCH_MASK));
We need to clean this up before modifying the GPE dispatcher type values.
In order to prevent such issue from happening in the future, this patch
introduces ACPI_GPE_DISPATCH_TYPE() macro to be used to obtain the GPE
dispatcher types. Lv Zheng.
Link: https://github.com/acpica/acpica/commit/7926d5ca
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: David E. Box <david.e.box@linux.intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPICA commit 04f25acdd4f655ae33f83de789bb5f4b7790171c
This patch follows acpi_ev_fixed_event_detect(), which invokes
acpi_gbl_global_event_handler instead of invoking it in
acpi_ev_fixed_event_dispatch(), moves acpi_gbl_global_event_handler from
acpi_ev_gpe_dispatch() to acpi_ev_gpe_detect(). This makes further cleanups
around acpi_ev_gpe_dispatch() simpler. Lv Zheng.
Link: https://github.com/acpica/acpica/commit/04f25acd
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: David E. Box <david.e.box@linux.intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPICA commit b2b18bb38045404e253f10787b8a4ae6e94cdee6
This patch prevents acpi_remove_gpe_handler() from leaking the stale
gpe_event_info->Dispatch.Handler to the caller to avoid possible NULL pointer
references. Lv Zheng.
Link: https://github.com/acpica/acpica/commit/b2b18bb3
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: David E. Box <david.e.box@linux.intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPICA commit 8e21180050270897499652e922c6a41b8eb388b6
Recent changes to acpi_ev_asynch_execute_gpe_method left Status
variable uninitialized before use. Initialize to AE_OK.
Link: https://github.com/acpica/acpica/commit/8e211800
Signed-off-by: David E. Box <david.e.box@linux.intel.com>
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>
ACPICA commit 8823b44ff53859ab24ecfcfd3fba8cc56b17d223
Currently we rely on the logic that GPE blocks will never be deleted,
otherwise we can be broken by the race between acpi_ev_create_gpe_block(),
acpi_ev_delete_gpe_block() and acpi_ev_gpe_detect().
On the other hand, if we want to protect GPE block creation/deletion, we
need to use a different synchronization facility to protect the period
between acpi_ev_gpe_dispatch() and acpi_ev_asynch_enable_gpe(). Which leaves us
no choice but abandoning the ACPI_MTX_EVENTS used during this period.
This patch removes ACPI_MTX_EVENTS used during this period and the
acpi_ev_valid_gpe_event() to reflect current restriction. Lv Zheng.
Link: https://github.com/acpica/acpica/commit/8823b44f
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: David E. Box <david.e.box@linux.intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPICA commit ca10324788bc9bdaf47fa9e51145129c1299144d
This patch deletes a sanity check from acpi_ev_enable_gpe().
This kind of check is already done in
acpi_enable_gpe()/acpi_remove_gpe_handler()/acpi_update_all_gpes() before invoking
acpi_ev_enable_gpe():
1. acpi_enable_gpe(): same check (skip if DISPATCH_NONE) is now implemented.
2. acpi_remove_gpe_handler(): a more strict check (skip if !DISPATCH_HANDLER)
is implemented.
3. acpi_update_all_gpes(): a more strict check (skip if DISPATCH_NONE ||
DISPATCH_HANDLER || CAN_WAKE)
4. acpi_set_gpe(): since it is invoked by the OSPM driver where the GPE
handler is known to be available, such check isn't needed.
So we can simply remove this duplicated check from acpi_ev_enable_gpe().
Lv Zheng.
Link: https://github.com/acpica/acpica/commit/ca103247
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: David E. Box <david.e.box@linux.intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This is a back port result of the Linux commit:
Commit c50f13c672
Subject: ACPICA: Save current masks of enabled GPEs after enable register writes
Besides of the indent divergences, only a missing prototype added due to
the ACPICA internal coding style.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Introduce a common ->enter callback routine for the ACPI cpuidle
driver, acpi_idle_enter(), which helps to reduce code complexity,
size and duplication and prevents theoretically possible failues that
an incorrect routine may be run to enter the given idle state due to
a firmware bug (eg. when _CST returns a different set of states for
each processor).
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
acpi_idle_enter_c1() and acpi_idle_enter_simple() are close enough to
each other that they can be merged into one function which reduces
duplication of code quite a bit.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Revert commit 6c17ee44d5 (ACPI / LPSS: introduce a 'proxy' device
to power on LPSS for DMA), as it introduced registration and probe
ordering problems between devices on the LPSS that may lead to full
hard system hang on boot in some cases.
Since acpi_idle_enter_bm() is only used if flags.bm_check is set for
the given acpi_processor object, it doesn't make sense to check that
flag in there.
For this reason, drop flags.bm_check tests (and some code depending
on them) from acpi_idle_enter_bm().
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
White space in the switch statement in acpi_processor_setup_cpuidle_states()
does not adhere to the kernel coding style and that makes the code
difficult to read. Clean that up.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The comment about bus master disable in acpi_idle_enter_simple() is
irrelevant, because the function doesn't disable bus mastering, so
drop it.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
acpi_idle_enter_simple() and acpi_idle_enter_bm() both check
if C2/C3 type entry is supported on MP in the same way, so move
those checks to a separate function and call it from both
places (and it doesn't need to check if the state type is not
C1, because the functions in question won't be called otherwise).
While at it, use IS_ENABLED() for the CONFIG_HOTPLUG_CPU check.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
acpi_idle_enter_simple() and acpi_idle_enter_bm() don't need to
call sched_clock_idle_sleep/wakeup_event(), because that's taken
care of by the core already. Namely, sched_clock_idle_sleep_event()
is called by tick_nohz_start_idle() called by __tick_nohz_idle_enter()
which in turn is called by tick_nohz_idle_enter() and that is called
by cpu_idle_loop(). Analogously for sched_clock_idle_wakeup_event().
For this reason, drop those calls from the ACPI cpuidle driver's
->enter callback routines.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Since the cpuidle core calls stop_critical_timings() and
start_critical_timings() around the execution of ->enter callbacks,
acpi_idle_do_entry() doesn't need to do that (and really shouldn't).
Also using "inline" on it is pointless and the kerneldoc entry does
not reflect the actual situation any more.
Fix all of the above.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
struct acpi_resource_address and struct acpi_resource_extended_address64 share substracts
just at different offsets. To unify the parsing functions, OSPMs like Linux
need a new ACPI_ADDRESS64_ATTRIBUTE as their substructs, so they can
extract the shared data.
This patch also synchronizes the structure changes to the Linux kernel.
The usages are searched by matching the following keywords:
1. acpi_resource_address
2. acpi_resource_extended_address
3. ACPI_RESOURCE_TYPE_ADDRESS
4. ACPI_RESOURCE_TYPE_EXTENDED_ADDRESS
And we found and fixed the usages in the following files:
arch/ia64/kernel/acpi-ext.c
arch/ia64/pci/pci.c
arch/x86/pci/acpi.c
arch/x86/pci/mmconfig-shared.c
drivers/xen/xen-acpi-memhotplug.c
drivers/acpi/acpi_memhotplug.c
drivers/acpi/pci_root.c
drivers/acpi/resource.c
drivers/char/hpet.c
drivers/pnp/pnpacpi/rsparser.c
drivers/hv/vmbus_drv.c
Build tests are passed with defconfig/allnoconfig/allyesconfig and
defconfig+CONFIG_ACPI=n.
Original-by: Thomas Gleixner <tglx@linutronix.de>
Original-by: Jiang Liu <jiang.liu@linux.intel.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
ACPICA has implemented acpi_unload_parent_table() which can exactly replace
the acpi_get_id()/acpi_unload_table_id() implemented in Linux kernel. The
acpi_unload_parent_table() has been unit tested in ACPICA simulation
environment.
This patch can also help to reduce the source code differences between
Linux and ACPICA.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Octavian Purdila <octavian.purdila@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This makes a difference if the compiler decides not to inline the
function, as then the function's reference to acpisleep_dmi_table[]
yields a section mismatch warning.
Signed-off-by: Jan Beulich <jbeulich@suse.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Intel Lynxpoint I2C does not have clock parameter register like SPI and UART
do have. Therefore remove LPSS_CLK_GATE flag from the Lynxpoint I2C device
description in order to not needlessly toggle clock enable bit in
non-existing register.
Signed-off-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The QR_EC related code pieces have redundants, this patch merges them into
acpi_ec_query() which invokes acpi_ec_transaction() where EC mutex and the
global lock are already held. After doing so, query handler traversal still
need to be locked by EC mutex after invoking acpi_ec_transaction().
Note that EC event handling is sequential. We fetch one event from firmware
event queue and process it until 0x00 or error returned. So we don't need
to hold mutex for whole acpi_ec_clear() process to determine whether we
should continue to drain. And for the same reason, we don't need to hold
mutex for the whole procedure from the QR_EC transaction to the query
handler traversal.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This patch fixes 2 issues related to the draining behavior. But it doesn't
implement the draining support, it only cleans up code so that further
draining support is possible.
The draining behavior is expected by some platforms (for example, Samsung)
where SCI_EVT is set only once for a set of events and might be cleared for
the very first QR_EC command issued after SCI_EVT is set. EC firmware on
such platforms will return 0x00 to indicate "no outstanding event". Thus
after seeing an SCI_EVT indication, EC driver need to fetch events until
0x00 returned (see acpi_ec_clear()).
Issue 1 - acpi_ec_submit_query():
It's reported on Samsung laptops that SCI_EVT isn't checked when the
transactions are advanced in ec_poll(), which leads to SCI_EVT triggering
source lost:
If no EC GPE IRQs are arrived after that, EC driver cannot detect this
event and handle it.
See comment 244/247 for kernel bugzilla 44161.
This patch fixes this issue by moving SCI_EVT checks into
advance_transaction(). So that SCI_EVT is checked each time we are going to
handle the EC firmware indications. And this check will happen for both IRQ
context and task context.
Since after doing that, SCI_EVT is also checked after completing a
transaction, ec_check_sci() and ec_check_sci_sync() can be removed.
Issue 2 - acpi_ec_complete_query():
We expect to clear EC_FLAGS_QUERY_PENDING to allow queuing another draining
QR_EC after writing a QR_EC command and before reading the event. After
reading the event, SCI_EVT might be cleared by the firmware, thus it may
not be possible to queue such a draining QR_EC at that time.
But putting the EC_FLAGS_QUERY_PENDING clearing code after
start_transaction() is wrong as there are chances that after
start_transaction(), QR_EC can fail to be sent. If this happens,
EC_FLAG_QUERY_PENDING will be cleared earlier. As a consequence, the
draining QR_EC will also be queued earlier than expected.
This patch also moves this code into advance_transaction() where QR_EC is
just sent (ACPI_EC_COMMAND_POLL flagged) to fix this issue.
Notes:
1. After introducing the 2 SCI_EVT related handlings into
advance_transaction(), a next QR_EC can be queued right after writing
the current QR_EC command and before reading the event. But this still
hasn't implemented the draining behavior as the draining support
requires:
If a previous returned event value isn't 0x00, a draining QR_EC need
to be issued even when SCI_EVT isn't set.
2. In this patch, acpi_os_execute() is also converted into a seperate work
item to avoid invoking kmalloc() in the atomic context. We can do this
because of the previous global lock fix.
3. Originally, EC_FLAGS_EVENT_PENDING is also used to avoid queuing up
multiple work items (created by acpi_os_execute()), this can be covered
by only using a single work item. But this patch still keeps this flag
as there are different usages in the driver initialization steps relying
on this flag.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=44161
Reported-by: Kieran Clancy <clancy.kieran@gmail.com>
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Currently QR_EC is queued up on CPU 0 to be safe with SMM because there is
no global lock held for acpi_ec_gpe_query(). As we are about to move QR_EC
to a non CPU 0 bound work queue to avoid invoking kmalloc() in
advance_transaction(), we have to acquire global lock for the new QR_EC
work item to avoid regressions.
Known issue:
1. Global lock for acpi_ec_clear().
This is an existing issue that acpi_ec_clear() which invokes
acpi_ec_sync_query() also suffers from the same issue. But this patch's
target is only the code to invoke acpi_ec_sync_query() in a CPU 0 bound
work queue item, and the acpi_ec_clear() can be automatically fixed by
further patch that merges the redundant code, so it is left unchanged.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The returning value of acpi_os_execute() is erroneously handled as errno.
This patch corrects it by returning EBUSY to indicate the work queue item
creation failure.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This patch adds reference counting for query handlers in order to eliminate
kmalloc()/kfree() usage.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Tested-by: Steffen Weber <steffen.weber@gmail.com>
Tested-by: Ortwin Glück <odi@odi.ch>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This patch moves transaction wakeup code into advance_transaction().
No functional changes.
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
If it fails we have to skip the device.
Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
