The amthif client connection is shared over multiple file descriptors.
In case a file descriptor was closed immediately after a write, the read
credits should be still available so the pending reads can be cleaned
from the queue, hence we cannot drop the control read list, this is
done only upon connection close.
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

In order to prevent memory leak clean up the amthif command
queue upon disconnection. The issue may happen only on error path
as the command queue is cleaned upon file descriptor close.
And remove the cleanup from mei_cl_flush_queues as this code
is never reached for amthif client.
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

On legacy HW, pre Skylake, the notifications are not supported,
return -EOPNOTSUPP in mei_cl_notify_get and prevent
waiting indefinitely.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Request for a notification from a disconnected client will be ignored
silently by the FW but the caller should know that the operation hasn't
succeeded.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Stop and unregister receive and notification callbacks
from the disable function, to allow its later re-enablement.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The hardware module should not be unloaded if the bus
has active devices.
Get get_/put_ bus parent module upon client device
connection/disconnection, to prevent the hardware managing
module to disappear underneath.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

A driver on the mei bus may rely on the availability
of the receive callback during driver remove() call, e.g. mei_wdt.
Move callbacks dismantling after the remove() call to unblock that scenario.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

mei_cl_set_disconnected is used only in client.c,
so make it local to the file and mark static.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

mei_io_list_flush is used only in client.c
so make it local to the file and mark static.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Sending OS version for support of TPM2_ChangeEPS() is required only
for SPT FW (HMB version 2.0) and newer.
On older platforms the command should be just ignored by the firmware
but some older platforms misbehave so it's safer to send the command
only if required.

Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=192051
Fixes: 7279b238 (mei: send OS type to the FW)
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Tested-by: NJan Niehusmann <jan@gondor.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The credentials handling was pushed to the write handlers
but error handling wasn't done properly.
Move write callbacks to completion queue to destroy them
and to notify a blocked writer about the failure

Fixes: 136698e5 (mei: push credentials inside the irq write handler)
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Adjust function name in KDoc.

Fixes: d49dc5e7 (mei: bus: use mei_cldev_ prefix for the API functions)
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Enable non-blocking receive for drivers on mei bus, this allows checking
for data availability by mei client drivers. This is most effective for
fixed address clients, that lacks flow control.

This function adds new API function mei_cldev_recv_nonblock(), it
retuns -EGAIN if function will block.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Since the newer HW sports two interrupts causes we cannot
just simply acknowledge the interrupts directly in the quick handler
and store the cause in the member variable, as the cause
will be overridden upon next interrupt while the interrupt thread
was not yet scheduled handling the previous interrupt.
The simple fix is to disable interrupts in quick handler
and acknowledge and enabled them in the interrupt thread.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

We need to synchronize irqs before issuing reset to make sure that the
clients communication is concluded and doesn't leak to the reset flow
and confusing the state machine.

This issue is happening during suspend/resume stress testing.
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add MEI Lewisburg PCH IDs for Purley based workstations.

Cc: <stable@vger.kernel.org> # 4.8.x
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

pm_runtime_autosuspend can take synchronous or asynchronous
paths, Because we are calling pm_runtime_mark_last_busy just before
this most of the cases it takes the asynchronous way. However,
when the FW or driver resets during already running runtime suspend,
the call will result in calling to the driver's rpm callback and results
in a deadlock on device_lock.
The simplest fix is to replace pm_runtime_autosuspend with
asynchronous pm_request_autosuspend.

Cc: <stable@vger.kernel.org> # 4.4+
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Split callbacks for RX and async notification events on mei bus to
eliminate synchronization problems and to open way for RX optimizations.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Change life time of the client pointer, allocate it upon client device
creation and free it upon device destruction, instead of upon
connection and disconnection.
This helps to eliminate racy NULL checks in the bus code.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Introduce a new host client state, MEI_FILE_UNINITIALIZED,
to distinguish client objects that was unlinked,
but not destroyed and can be linked again.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Parameter renaming to fop_type was not reflected in KDoc

Fixes: 3030dc05 (mei: add wrapper for queuing control commands)
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The write buffer should not by modified so make it constant. Also
hitchhike some style fixes on the way in the interface and rename
mei_me_write_message to mei_me_hbuf_write for consistency.
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

A cb is always placed on the completion queue
during discarding queue. Hence this can be performed
upon discard.
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Tell the FW that we are running a sane OS and TPM2_ChangeEPS()
is supported. This workaround was added to support other broken OS
and we need to follow here. The command is sent just once at the boot time.
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Prepare the client write functions to set the internal flag in message
header. Carry both blocking and internal modes inside the transmit cb,
and call internal bus function  __mei_cl_send() with send mode bit mask.
The Internal flag should be added only on messages generated by the
driver.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

NFC version reply size checked against only header size, not against
full message size. That may lead potentially to uninitialized memory access
in version data.

That leads to warnings when version data is accessed:
drivers/misc/mei/bus-fixup.c: warning: '*((void *)&ver+11)' may be used uninitialized in this function [-Wuninitialized]:  => 212:2

Reported in
Build regressions/improvements in v4.9-rc3
https://lkml.org/lkml/2016/10/30/57

Fixes: 59fcd7c6 (mei: nfc: Initial nfc implementation)
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

A mei client driver on the mei client bus can call disconnect function on
already internal disconnected client.  A client can disconnect internally,
for example, during link reset or upon FW request. Those are legitimate
flows and we should not log an error message, hence we demote
'Already disconnected' message to the debug level.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The HBM protocol version is negotiated during the setup phase, then settled
on a highest possible common version of the driver and the firmware.
The sysfs API advertises both negotiated and driver supported versions
in the device attributes.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The callback context is redunant as all the information can be
retrived from the device struture of its private data.
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

SEC registers are not accessible when the TXE device is in low power
state, hence the SEC interrupt cannot be processed if device is not
awake.

In some rare cases entrance to low power state (aliveness off) and input
ready bits can be signaled at the same time, resulting in communication
stall as input ready won't be signaled again after waking up. To resolve
this IPC_HHIER_SEC bit in HHISR_REG should not be cleaned if the
interrupt is not processed.

Cc: stable@vger.kernel.org
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The stall timer worker checks periodically if there is a stalled i/o
transaction. The issue with the current implementation is that the timer
is ticking also when there is no pending i/o transaction.
This patch provides a simple change that prevents rescheduling
of the delayed work when there is no pending i/o.

Cc: Andy Lutomirski <luto@kernel.org>
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add device ids for Intel Kabypoint PCH (Kabylake)

Cc: <stable@vger.kernel.org> #4.6+
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The device lock was unnecessary obtained in bus rescan work before the
amthif client search.  That causes incorrect lock ordering and task
hang:
...
[88004.613213] INFO: task kworker/1:14:21832 blocked for more than 120 seconds.
...
[88004.645934] Workqueue: events mei_cl_bus_rescan_work
...

The correct lock order is
 cl_bus_lock
  device_lock
   me_clients_rwsem

Move device_lock into amthif init function that called
after me_clients_rwsem is released.

This fixes regression introduced by commit:
commit 025fb792 ("mei: split amthif client init from end of clients enumeration")

Cc: <stable@vger.kernel.org> # 4.6+
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

mei_amthif_read have only one difference from mei_read, it is not
calling mei_read_start().
Make mei_read_start return immediately for amthif client and drop the
special mei_amthif_read function.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The FW supports only one pending read per host client, in order to
support  issuing of consecutive reads the driver  queues read requests
internally and send them to the firmware after pending one has
completed.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Enclose the boiler plate code of allocating a control/hbm command cb
and enqueueing it onto ctrl_wr.list in a convenient wrapper
mei_cl_enqueue_ctrl_wr_cb().

This is a preparatory patch for enabling consecutive reads.
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

With the introduction of the receive control flow credits prefixed with
rx_ we add tx_ prefix to the variables and function used for tracking
the transmit control flow credits.
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Use RX flow control counter in the host client structure to
track the number of simultaneous outstanding reads.
This eliminates search in queues and makes ground for
enabling for parallel read.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

The read callbacks for the fixed address clients, that don't have flow
control are built now on the receive path. In order to have a single
allocation place we remove the allocation from the read request.
Signed-off-by: NAlexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: NTomas Winkler <tomas.winkler@intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>