The protocol defines how to setup an I/O ring on top of host
memory to utilize the device DMA engine for faster transport.
Three memory buffers are allocated.
A Host circular buffer for from the Host to Device communication.
A Device circular buffer for from Device to the Host communication.
And finally a Control block where the pointers for the both
circular buffers are managed.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Remove header size knowledge from me and txe hw layers,
this requires to change the write handler to accept
header and its length as well as data and its length.
HBM messages are fixed to use basic header, hence we add mei_hbm2slots()
that converts HBM message length and mei message header,
while mei_data2slots() converts data length directly to the slots.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Wrap the mei header boilerplate initialization code in
mei_msg_hdr_init function. On the way remove 'completed'
field from mei_cl_cb structure as this information
is already included in the header and is local to particular
fragment.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The host buffer depth is hardware specific so it's better to
handle it inside the me and txe hw modules. In me the depth
is read from register in txe it's a constant number.
The value is now retrieved via mei_hbuf_depth accessor,
while it replaces mei_hbuf_max_len.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cleanup conversions between slots and data.
Define MEI_SLOT_SIZE instead of using 4 or sizeof(u32) across
the source code.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Comparison between signed and unsigned warnings
and associated type promotion may cause error
condition not be detected.
The type promotion issue in mei bus was addressed by two patches:
commit b40b3e9358 ("mei: bus: type promotion bug in mei_nfc_if_version()")
commit cf1ed2c59b ("mei: bus: type promotion bug in mei_fwver()")
Now it is possible to suppress the warning, by adding proper
casting to move out of radar.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use ssize_t for rets variables in mei_write(), mei_read(), and
mei_cl_write() as well as change the return type of mei_cl_write()
to ssize_t, to prevent assignment of possible 64bit size_t
to int 32 bit variable.
As by product also eliminate warning
drivers/misc/mei/client.c:1702:11: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
In for loops use same type for counter variable
as has the limiting variable.
drivers/misc/mei/bus-fixup.c:489:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
drivers/misc/mei/hw-txe.c:725:13: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
drivers/misc/mei/hw-txe.c:744:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mei_hbuf_empty_slots() may return with an error in case
of circular buffer overflow. This type of error may
be caused only by a bug. However currently, the error
won't be detected due signed type promotion in comparison to u32.
We add explicit check for less then zero and explicit cast
in comparison to suppress singn-compare warning.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
if __mei_cl_recv() returns a negative then "bytes_recv"
type is promoted to a high positive value in comparison with
size_t evaluated by MKHI_FWVER_LEN(1). It results in error condition
not to be detected.
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: 9078ad92ef86 ("mei: expose fw version to sysfs")
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
We accidentally removed the check for negative returns
without considering the issue of type promotion.
The "if_version_length" variable is type size_t so if __mei_cl_recv()
returns a negative then "bytes_recv" is type promoted
to a high positive value and treated as success.
Cc: <stable@vger.kernel.org>
Fixes: 582ab27a06 ("mei: bus: fix received data size check in NFC fixup")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This fixes regression introduced by
commit 8d52af6795 ("mei: speed up the power down flow")
In power down or suspend flow a message can still be received
from the FW because the clients fake disconnection.
In normal case we interpret messages w/o destination as corrupted
and link reset is performed in order to clean the channel,
but during power down link reset is already in progress resulting
in endless loop. To resolve the issue under power down flow we
discard messages silently.
Cc: <stable@vger.kernel.org> 4.16+
Fixes: 8d52af6795 ("mei: speed up the power down flow")
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199541
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The ME FW version is constantly used by detection and update tools.
To improve the reliability and simplify these tools provide
a sysfs interface to access version of the platform ME firmware
in the following format:
<platform>:<major>.<minor>.<milestone>.<build>.
There can be up to three such blocks for different FW components.
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Currently the driver spams the kernel log on unsupported ioctls which is
unnecessary as the ioctl returns -ENOIOCTLCMD to indicate this anyway.
I suspect this was originally for debugging purposes but it really is not
required so remove it.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Limit the number of queued writes per client.
Writes above this threshold are blocked till place
in the transmit queue is available.
The limit is configurable via sysfs and defaults to 50.
The implementation should provide blocking I/O behavior.
Prior to this change one would end up in the hands of OOM.
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Module reference counting is relevant only to the
mei client devices. Make the implementation clean
and move it to bus.c
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This fixes regression introduced by
commit 8d52af6795 ("mei: speed up the power down flow")
In mei_cldev_disable during device power down flow, such as
suspend or system power off, it jumps over disconnecting function
to speed up the power down process, however, because the client is
unlinked from the file_list (mei_cl_unlink) mei_cl_set_disconnected
is not called from mei_cl_all_disconnect leaving resource leaking.
The most visible is reference counter on underlying HW module is
not decreased preventing to remove modules after suspend/resume cycles.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Fixes: 8d52af6795 ("mei: speed up the power down flow")
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This is the mindless scripted replacement of kernel use of POLL*
variables as described by Al, done by this script:
for V in IN OUT PRI ERR RDNORM RDBAND WRNORM WRBAND HUP RDHUP NVAL MSG; do
L=`git grep -l -w POLL$V | grep -v '^t' | grep -v /um/ | grep -v '^sa' | grep -v '/poll.h$'|grep -v '^D'`
for f in $L; do sed -i "-es/^\([^\"]*\)\(\<POLL$V\>\)/\\1E\\2/" $f; done
done
with de-mangling cleanups yet to come.
NOTE! On almost all architectures, the EPOLL* constants have the same
values as the POLL* constants do. But they keyword here is "almost".
For various bad reasons they aren't the same, and epoll() doesn't
actually work quite correctly in some cases due to this on Sparc et al.
The next patch from Al will sort out the final differences, and we
should be all done.
Scripted-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tomas Winkler
Greg Kroah-Hartman
Alexander Usyskin
Dan Carpenter
Colin Ian King
Linus Torvalds