<feed xmlns='http://www.w3.org/2005/Atom'>
<title>BMC/Intel-BMC/linux.git/drivers/acpi/ec.c, branch dev-4.3</title>
<subtitle>Intel OpenBMC Linux kernel source tree (mirror)</subtitle>
<id>https://git.radix-linux.su/BMC/Intel-BMC/linux.git/atom?h=dev-4.3</id>
<link rel='self' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/atom?h=dev-4.3'/>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/'/>
<updated>2015-09-25T23:44:59+00:00</updated>
<entry>
<title>ACPI / EC: Fix a memory leak issue in acpi_ec_query()</title>
<updated>2015-09-25T23:44:59+00:00</updated>
<author>
<name>Lv Zheng</name>
<email>lv.zheng@intel.com</email>
</author>
<published>2015-09-24T06:54:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=15b94fa32a422f4b97dc34e4b7060ec83d10bee5'/>
<id>urn:sha1:15b94fa32a422f4b97dc34e4b7060ec83d10bee5</id>
<content type='text'>
When query handler is not found, "result" is actually stil 0, and
"struct acpi_ec_query" is not NULL, so the deletion code of
"struct acpi_ec_query" at the end of the function cannot be invoked.
As a consequence, memory leak can be observed.

The issue is introduced by this commit:
  Commit: 02b771b64b73226052d6e731a0987db3b47281e9
  Subject: ACPI / EC: Fix an issue caused by the serialized _Qxx

This patch fixes such memory leakage.

Fixes: 02b771b64b73 (ACPI / EC: Fix an issue caused by the serialized _Qxx evaluations)
Signed-off-by: Lv Zheng &lt;lv.zheng@intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
</entry>
<entry>
<title>Merge branches 'acpi-pci', 'acpi-soc', 'acpi-ec' and 'acpi-osl'</title>
<updated>2015-09-01T01:41:19+00:00</updated>
<author>
<name>Rafael J. Wysocki</name>
<email>rafael.j.wysocki@intel.com</email>
</author>
<published>2015-09-01T01:41:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=5d2a1a927d487d6bb60c87b837d82702d8ebcaad'/>
<id>urn:sha1:5d2a1a927d487d6bb60c87b837d82702d8ebcaad</id>
<content type='text'>
* acpi-pci:
  ACPI, PCI: Penalize legacy IRQ used by ACPI SCI

* acpi-soc:
  ACPI / LPSS: Ignore 10ms delay for Braswell

* acpi-ec:
  ACPI / EC: Fix an issue caused by the serialized _Qxx evaluations

* acpi-osl:
  ACPI / osl: replace custom implementation of readq / writeq
</content>
</entry>
<entry>
<title>ACPI / EC: Fix an issue caused by the serialized _Qxx evaluations</title>
<updated>2015-08-25T01:19:32+00:00</updated>
<author>
<name>Lv Zheng</name>
<email>lv.zheng@intel.com</email>
</author>
<published>2015-08-12T03:12:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=02b771b64b73226052d6e731a0987db3b47281e9'/>
<id>urn:sha1:02b771b64b73226052d6e731a0987db3b47281e9</id>
<content type='text'>
It is proven that Windows evaluates _Qxx handlers in a parallel way. This
patch follows this fact, splits _Qxx evaluations from the NOTIFY queue to
form a separate queue, so that _Qxx evaluations can be queued up on
different CPUs rather than being queued up on a CPU0 bound queue.
Event handling related callbacks are also renamed and sorted in this patch.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=94411
Reported-and-tested-by: Gabriele Mazzotta &lt;gabriele.mzt@gmail.com&gt;
Signed-off-by: Lv Zheng &lt;lv.zheng@intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
</entry>
<entry>
<title>ACPI: Remove FSF mailing addresses</title>
<updated>2015-07-08T00:27:32+00:00</updated>
<author>
<name>Jarkko Nikula</name>
<email>jarkko.nikula@linux.intel.com</email>
</author>
<published>2015-06-26T08:27:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=4c62dbbce902cf2afa88cac89ec67c828160f431'/>
<id>urn:sha1:4c62dbbce902cf2afa88cac89ec67c828160f431</id>
<content type='text'>
There is no need to carry potentially outdated Free Software Foundation
mailing address in file headers since the COPYING file includes it.

Signed-off-by: Jarkko Nikula &lt;jarkko.nikula@linux.intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
</entry>
<entry>
<title>ACPI / EC: Fix a code coverity issue when QR_EC transactions are failed.</title>
<updated>2015-06-15T12:35:59+00:00</updated>
<author>
<name>Lv Zheng</name>
<email>lv.zheng@intel.com</email>
</author>
<published>2015-06-11T05:21:51+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=66db383439b51b1aa920f3579da644fb5fdb2b7c'/>
<id>urn:sha1:66db383439b51b1aa920f3579da644fb5fdb2b7c</id>
<content type='text'>
When the QR_EC transaction fails, the EC_FLAGS_QUERY_PENDING flag prevents
the event handling work queue from being scheduled again.

Though there shouldn't be failed QR_EC transactions, and this gap was
efficiently used for catching and learning the SCI_EVT clearing timing
compliance issues, we need to fix this as we are not fully compatible
with all platforms/Windows to handle SCI_EVT clearing timing correctly.
Fixing this gives the EC driver the chances to recover from a state machine
failure.

So this patch fixes this issue. When nr_pending_queries drops to 0, it
clears EC_FLAGS_QUERY_PENDING at the proper position for different modes in
order to ensure that the SCI_EVT handling can proceed.

In order to be clearer for future ec_event_clearing modes, all checks in
this patch are written in the inclusive style, not the exclusive style.

Cc: 3.16+ &lt;stable@vger.kernel.org&gt; # 3.16+
Signed-off-by: Lv Zheng &lt;lv.zheng@intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
</entry>
<entry>
<title>ACPI / EC: Fix EC_FLAGS_QUERY_HANDSHAKE platforms using new event clearing timing.</title>
<updated>2015-06-15T12:35:59+00:00</updated>
<author>
<name>Lv Zheng</name>
<email>lv.zheng@intel.com</email>
</author>
<published>2015-06-11T05:21:45+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=3cb02aeb28dd3f1b8a132fa3ecf6db17afd518d6'/>
<id>urn:sha1:3cb02aeb28dd3f1b8a132fa3ecf6db17afd518d6</id>
<content type='text'>
It is reported that on several platforms, EC firmware will not respond
non-expected QR_EC (see EC_FLAGS_QUERY_HANDSHAKE, only write QR_EC when
SCI_EVT is set).

Unfortunately, ACPI specification doesn't define when the SCI_EVT should be
cleared by the firmware, thus the original implementation queued up second
QR_EC right after writing QR_EC command and before reading the returned
event value as at that time the SCI_EVT is ensured not cleared. This
behavior is also based on the assumption that the firmware should be able
to return 0x00 to indicate "no outstanding event". This behavior did fix
issues on Samsung platforms where the spurious query value of 0x00 is
supported and didn't break platforms in my test queue.

But recently, specific Acer, Asus, Lenovo platforms keep on blaming this
change.

This patch changes the behavior to re-check the SCI_EVT a bit later and
removes EC_FLAGS_QUERY_HANDSHAKE quirks, hoping this is the Windows
compliant EC driver behavior.

In order to be robust to the possible regressions, instead of removing the
quirk directly, this patch keeps the quirk code, removes the quirk users
and keeps old behavior for Samsung platforms.

Cc: 3.16+ &lt;stable@vger.kernel.org&gt; # 3.16+
Link: https://bugzilla.kernel.org/show_bug.cgi?id=94411
Link: https://bugzilla.kernel.org/show_bug.cgi?id=97381
Link: https://bugzilla.kernel.org/show_bug.cgi?id=98111
Reported-and-tested-by: Gabriele Mazzotta &lt;gabriele.mzt@gmail.com&gt;
Reported-and-tested-by: Tigran Gabrielyan &lt;tigrangab@gmail.com&gt;
Reported-and-tested-by: Adrien D &lt;ghbdtn@openmailbox.org&gt;
Signed-off-by: Lv Zheng &lt;lv.zheng@intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
</entry>
<entry>
<title>ACPI / EC: Add event clearing variation support.</title>
<updated>2015-06-15T12:35:59+00:00</updated>
<author>
<name>Lv Zheng</name>
<email>lv.zheng@intel.com</email>
</author>
<published>2015-06-11T05:21:38+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=1d68d2612c2e7309166fa43d8e27eb163435527f'/>
<id>urn:sha1:1d68d2612c2e7309166fa43d8e27eb163435527f</id>
<content type='text'>
We've been suffering from the uncertainty of the SCI_EVT clearing timing.
This patch implements 3 of 4 possible modes to handle SCI_EVT clearing
variations. The old behavior is kept in this patch.

Status: QR_EC is re-checked as early as possible after checking previous
        SCI_EVT. This always leads to 2 QR_EC transactions per SCI_EVT
        indication and the target may implement event queue which returns
        0x00 indicating "no outstanding event".
        This is proven to be a conflict against Windows behavior, but is
        still kept in this patch to make the EC driver robust to the
        possible regressions that may occur on Samsung platforms.
Query: QR_EC is re-checked after the target has handled the QR_EC query
       request command pushed by the host.
Event: QR_EC is re-checked after the target has noticed the query event
       response data pulled by the host.
       This timing is not determined by any IRQs, so we may need to use a
       guard period in this mode, which may explain the existence of the
       ec_guard() code used by the old EC driver where the re-check timing
       is implemented in the similar way as this mode.
Method: QR_EC is re-checked as late as possible after completing the _Qxx
        evaluation. The target may implement SCI_EVT like a level triggered
        interrupt.
        It is proven on kernel bugzilla 94411 that, Windows will have all
        _Qxx evaluations parallelized. Thus unless required by further
        evidences, we needn't implement this mode as it is a conflict of
        the _Qxx parallelism requirement.

Note that, according to the reports, there are platforms that cannot be
handled using the "Status" mode without enabling the
EC_FLAGS_QUERY_HANDSHAKE quirk. But they can be handled with the other
modes according to the tests (kernel bugzilla 97381).

The following log entry can be used to confirm the differences of the 3
modes as it should appear at the different positions for the 3 modes:
  Command(QR_EC) unblocked
Status: appearing after
         EC_SC(W) = 0x84
Query: appearing after
         EC_DATA(R) = 0xXX
       where XX is the event number used to determine _QXX
Event: appearing after first
         EC_SC(R) = 0xX0 SCI_EVT=x BURST=0 CMD=0 IBF=0 OBF=0
       that is next to the following log entry:
         Command(QR_EC) completed by hardware

Link: https://bugzilla.kernel.org/show_bug.cgi?id=94411
Link: https://bugzilla.kernel.org/show_bug.cgi?id=97381
Link: https://bugzilla.kernel.org/show_bug.cgi?id=98111
Reported-and-tested-by: Gabriele Mazzotta &lt;gabriele.mzt@gmail.com&gt;
Reported-and-tested-by: Tigran Gabrielyan &lt;tigrangab@gmail.com&gt;
Reported-and-tested-by: Adrien D &lt;ghbdtn@openmailbox.org&gt;
Signed-off-by: Lv Zheng &lt;lv.zheng@intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
</entry>
<entry>
<title>ACPI / EC: Convert event handling work queue into loop style.</title>
<updated>2015-06-15T12:35:59+00:00</updated>
<author>
<name>Lv Zheng</name>
<email>lv.zheng@intel.com</email>
</author>
<published>2015-06-11T05:21:32+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=9d8993be2d9149bc8b3132dad030ff5960f5abcc'/>
<id>urn:sha1:9d8993be2d9149bc8b3132dad030ff5960f5abcc</id>
<content type='text'>
During the period that a work queue is scheduled (queued up for run) but
hasn't been run, second schedule_work() could fail. This may not lead to
the loss of queries because QR_EC is always ensured to be submitted after
the work queue has been in the running state.

The event handling work queue can be changed into the loop style to allow
us to control the code in a more flexible way:
1. Makes it possible to add event=0x00 termination condition in the loop.
2. Increases the thoughput of the QR_EC transactions as the 2nd+ QR_EC
   transactions may be handled in the same work item used for the 1st QR_EC
   transaction, thus the delay caused by the 2nd+ work item scheduling can
   be eliminated.

Except the logging message changes and the throughput improvement, this
patch is just a funcitonal no-op.

Signed-off-by: Lv Zheng &lt;lv.zheng@intel.com&gt;
Tested-by: Gabriele Mazzotta &lt;gabriele.mzt@gmail.com&gt;
Tested-by: Tigran Gabrielyan &lt;tigrangab@gmail.com&gt;
Tested-by: Adrien D &lt;ghbdtn@openmailbox.org&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
</entry>
<entry>
<title>ACPI / EC: Cleanup transaction state transition.</title>
<updated>2015-06-15T12:35:58+00:00</updated>
<author>
<name>Lv Zheng</name>
<email>lv.zheng@intel.com</email>
</author>
<published>2015-06-11T05:21:23+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=f8b8eb71533338654f39211a87efeca35055566b'/>
<id>urn:sha1:f8b8eb71533338654f39211a87efeca35055566b</id>
<content type='text'>
This patch collects transaction state transition code into one function. We
then could have a single function to maintain transaction transition
related behaviors. No functional changes.

Signed-off-by: Lv Zheng &lt;lv.zheng@intel.com&gt;
Tested-by: Gabriele Mazzotta &lt;gabriele.mzt@gmail.com&gt;
Tested-by: Tigran Gabrielyan &lt;tigrangab@gmail.com&gt;
Tested-by: Adrien D &lt;ghbdtn@openmailbox.org&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
</entry>
<entry>
<title>ACPI / EC: Remove non-root-caused busy polling quirks.</title>
<updated>2015-05-15T23:53:03+00:00</updated>
<author>
<name>Lv Zheng</name>
<email>lv.zheng@intel.com</email>
</author>
<published>2015-05-15T06:37:11+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/BMC/Intel-BMC/linux.git/commit/?id=3174abcfea6a05aa25038156d6722b6c8876fb36'/>
<id>urn:sha1:3174abcfea6a05aa25038156d6722b6c8876fb36</id>
<content type='text'>
{ Update to correct 1 patch subject in the description }

We have fixed a lot of race issues in the EC driver recently.

The following commit introduces MSI udelay()/msleep() quirk to MSI laptops
to make EC firmware working for bug 12011 without root causing any EC
driver race issues:
  Commit: 5423a0cb3f74c16e90683f8ee1cec6c240a9556e
  Subject: ACPI: EC: Add delay for slow MSI controller
  Commit: 34ff4dbccccce54c83b1234d39b7ad9e548a75dd
  Subject: ACPI: EC: Separate delays for MSI hardware

The following commit extends ECDT validation quirk to MSI laptops to make
EC driver locating EC registers properly for bug 12461:
  Commit: a5032bfdd9c80e0231a6324661e123818eb46ecd
  Subject: ACPI: EC: Always parse EC device
This is a different quirk than the MSI udelay()/msleep() quirk. This patch
keeps validating ECDT for only "Micro-Star MS-171F" as reported.

The following commit extends MSI udelay()/msleep() quirk to Quanta laptops
to make EC firmware working for bug 20242, there is no requirement to
validate ECDT for Quanta laptops:
  Commit: 534bc4e3d27096e2f3fc00c14a20efd597837a4f Mon Sep 17 00:00:00 2001
  Subject: ACPI EC: enable MSI workaround for Quanta laptops

The following commit extends MSI udelay()/msleep() quirk to Clevo laptops
to make EC firmware working for bug 77431, there is no requirement to
validate ECDT for Clevo laptops:
  Commit: 777cb382958851c88763253fe00a26529be4c0e9
  Subject: ACPI / EC: Add msi quirk for Clevo W350etq

All udelay()/msleep() quirks for MSI/Quanta/Clevo seem to be the wrong
fixes generated without fixing the EC driver race issues.
And even if it is not wrong, the guarding can be covered by the following
commits in wait polling mode:
  Commit: 9e295ac14d6a59180beed0735e6a504c2ee87761
  Subject: ACPI / EC: Reduce ec_poll() by referencing the last register access timestamp.
  Commit: commit in the same series
  Subject: ACPI / EC: Fix and clean up register access guarding logics.
The only case that is not covered is the inter-transaction guarding. And
there is no evidence that we need the inter-transaction guarding upon
reading the noted bug entries.

So it is time to remove the quirks and let the users to try again. If there
is a regression, the only thing we need to do is to restore the
inter-transaction guarding for the reported platforms.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=12011
Link: https://bugzilla.kernel.org/show_bug.cgi?id=12461
Link: https://bugzilla.kernel.org/show_bug.cgi?id=20242
Link: https://bugzilla.kernel.org/show_bug.cgi?id=77431
Signed-off-by: Lv Zheng &lt;lv.zheng@intel.com&gt;
Signed-off-by: Rafael J. Wysocki &lt;rafael.j.wysocki@intel.com&gt;
</content>
</entry>
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