The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Acked-by: Dimitri Sivanich <sivanich@hpe.com>
Link: https://lore.kernel.org/r/20200226222240.GA14474@embeddedor
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The MEI message header provides only 9 bits for storing
the message size, limiting to 511.
In theory the host buffer (hbuf) can contain up to 1020 bytes
(limited by byte = 255 * 4)
With the current hardware and hbuf size 512, this is not a real issue,
but as hardening approach we enforce the limit.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20200211160522.7562-1-tomas.winkler@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use unified version of the copyright notice in the files
Update copyright years according the year the files
were touched, except this patch and SPDX conversions.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Replace boiler plate licenses texts with the SPDX license
identifiers in the mei files header.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
single_recv_buf member of struct mei_client_properties has a boolean
value and can be represented in on bit, to free other 7 bits
for another usage.
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>
Bump HBM version to 2.1 to indicate DMA transfer support.
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>
Implement circular buffer protocol over receive dma
buffer. Add extension to the mei message header that holds
length of the buffer on the dma buffer.
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>
The DMA ring control block contains write and read
indices for host and device circular buffers.
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>
Only a firmware with version 2.1 and above supports dma ring feature.
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>
Add dma_ring bit in the mei message header for conveying
that the message data itself are on the dma ring.
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>
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>
MEI_IAMTHIF_STALL_TIMER is unused now and can be safely removed.
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>
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: 7279b238ba (mei: send OS type to the FW)
Signed-off-by: Alexander Usyskin <alexander.usyskin@intel.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Tested-by: Jan Niehusmann <jan@gondor.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signal the FW that it can send an HBM enumeration answer immediately,
without waiting for FW initialization completion, meaning before
all the FW clients are ready and registered.
Organize enumeration response options to enum as a byproduct.
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>
Enable by default connection to fixed address clients
from user-space for skylake and newer platform.
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>
Since the driver now uses a list for storing read packets instead of
single variable a pending read is no longer blocking other connections.
A pending read will be discarded up the file closure.
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>
HBM 2.0 version for Sunrise point Skylake (PCH) based devices
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Rework mei power gating state machine to support entry and exit to and
from D0i3 power state.
The choice between legacy and D0i3 routines is conditioned on
d0i3_supported flag.
The patch introduces warning:
drivers/misc/mei/hw-me.c:901:12: warning: ‘mei_me_d0i3_enter’ defined but not used [-Wunused-function]
it will go away in consequent patch
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 device can return error 5 (NOT_ALLOWED) on connection attempt.
This error can happen if:
1. An another connection attempt is in progress
2. There is an attempt to connect a fixed (connectionless) client
3. The number of available connections is exceeded (new in HBM 2.0)
We should not hit that error unless there is an internal book keeping
hiccup except option (3), therefore we translate the error code
to errno EBUSY;
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>
Only FW version 2.0 and newer support the async event
notification. For backward compatibility block the feature
if the FW version is older then 2.0
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>
FW has gained new capability where a FW client can asynchronously
notify the host that an event has occurred in its process.
The notification doesn't provide any data and host may need to query
further the FW client in order to get details of the event.
Host can subscribe or unsubscribe to the event notification via
designated HBM commands, and also the notification is carried on
a new HBM command.
This patch adds definitions of asynchronous notification HBM commands.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
For the FW with HBM version >= 2.0 we don't need to reset the whole
device in case of a particular client failing to connect, it is enough
to send disconnect a request to bring the device to the stable state.
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>
HBM version 2.0 and above allows ME clients in the system to
register/unregister after the system is fully initialized.
Clients may be added or removed after enum_resp message was
received
1. To preserve backward compatibility the driver can opt-in to receive
client add messages by setting allow_add field in enum_req
2. A new client is added upon reception of MEI_HBM_ADD_CLIENT_REQ_CMD
3. A client is removed in a lazy manner when connection request
respond with MEI_HBMS_CLIENT_NOT_FOUND status
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
HBM uses global list of status values
from which the values of particular commands
are derived
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Use consistently me_addr name in hbm protocol structures
to represent in firmware client address
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>
Communicate hbm version 1.1 to firmware to tell that we
now support power gating isolation protocol
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
For power gating entry we write hbm pg entry request command and
then we set pg register
For power gating exit we clear pg register and wait for exit request
hbm command.
Exit power gating request might also be initiated by the firmware
w/o explicit driver request
The power gating state is tracked by pg_state member of me_hw
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>
Enable power gating isolation only if hw and fw support it.
This is indicated by ME_PGIC_HRA bit in ME_CSR_HA register
and on HBM protocol version.
The information is exported to MEI layer through
new pg_is_enabled hw op.
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>
Add send message functions and receive dispatch stubs
for power gating isolation hbm protocol.
The protocol consist of requests for entering and exiting
the power gating isolation state and their responses.
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>
1. Return -ENOTTY on client connect if the requested client was not found
on the enumeration list or the client was internally disabled, in the later
case FW will return NOT_FOUND.
2. Return -EBUSY if the client cannot be connected because of resource
contention
3. Change response status enum to have MEI_CL_ prefix
4. Add function to translate response status to a string
for more readable logging
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>
In some rare case mei hw reset may take long time to settle.
Instead of blocking resume flow we span another driver reset flow in
separate work context
This allows as to shorten hw reset timeout to something more acceptable
by DPM_WATCHDOG_TIMEOUT
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>
Set hbm header bit 30 for internal commands
This mark commands that are generated by
the device driver
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Define a new parent type mei_hbm_cl_cmd for hbm
commands that are sent on behalf of specific ME client.
This allows us compacting boilerplate code via mei_hbm_cl_hdr
function
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Move struct mei_me_client from hw.h to mei_dev.h as it is not
part of the hardware API. The structutre doesn't have to
be packed. Add kdoc for this structure.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Internal clients numbers are implementation choice
and not defined by the hardware.
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
structs hbm_client_connect_request and hbm_client_disconnect_request
have the same layout so we can drop the later
Add kdoc for the request and response structure so it is clear
they can be used for both purposes
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1. The hardware book defines timeouts in seconds
so we stick to this and define the wrapper function
mei_secs_to_jiffies around msecs_to_jiffies
to use be used instead multiplying by HZ
2. We add name space prefix MEI_ to all timer defines
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1. reformat PCI ids list in hw.h for better readability
2. update some code and brand names
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
It's been cleaned up, and there's nothing else left to do, so move it
out of staging into drivers/misc/ where all can use it now.
Cc: Tomas Winkler <tomas.winkler@intel.com>
Cc: Oren Weil <oren.jer.weil@intel.com>
Cc: Alan Cox <alan@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Gustavo A. R. Silva