Commit Graph

20 Commits

Author SHA1 Message Date
Cristian Marussi 1fc2dd1864 firmware: arm_scmi: Add notification protocol-registration
Add the core SCMI notifications protocol-registration support: allow
protocols to register their own set of supported events, during their
initialization phase. Notification core can track multiple platform
instances by their handles.

Link: https://lore.kernel.org/r/20200701155348.52864-2-cristian.marussi@arm.com
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-07-01 17:07:25 +01:00
Cristian Marussi 87dff4e63c firmware: arm_scmi: Rename .clear_notification() transport_ops
SCMI transport operation .clear_notification() is indeed a generic method
to clear the channel in a transport dependent way, as such it could be a
useful helper also in other contexts.

Rename such method as .clear_channel(), renaming accordingly also its
already existent call-sites.

No functional change.

Link: https://lore.kernel.org/r/20200420152315.21008-2-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-04-20 17:25:26 +01:00
Cristian Marussi d5141f37c4 firmware: arm_scmi: Add notifications support in transport layer
Add common transport-layer methods to:
 - fetch a notification instead of a response
 - clear a pending notification

Add also all the needed support in mailbox/shmem transports.

Link: https://lore.kernel.org/r/20200327143438.5382-4-cristian.marussi@arm.com
Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-04-14 09:31:49 +01:00
Peng Fan 1dc6558062 firmware: arm_scmi: Add smc/hvc transport
Use the value of "arm,smc-id" property from the device tree as the first
argument for SMCCC call leaving all the other arguments as zero for now.

There is no Rx, only Tx because of smc/hvc not support Rx.

Link: https://lore.kernel.org/r/1583673879-20714-3-git-send-email-peng.fan@nxp.com
Signed-off-by: Peng Fan <peng.fan@nxp.com>
[sudeep.holla: reworded commit log/subject and fixed !HAVE_ARM_SMCCC build]
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-04-14 09:31:48 +01:00
Viresh Kumar 5c8a47a5a9 firmware: arm_scmi: Make scmi core independent of the transport type
The SCMI specification is fairly independent of the transport protocol,
which can be a simple mailbox (already implemented) or anything else.
The current Linux implementation however is very much dependent on the
mailbox transport layer.

This patch makes the SCMI core code (driver.c) independent of the
mailbox transport layer and moves all mailbox related code to a new
file: mailbox.c and all struct shared_mem related code to a new file:
shmem.c.

We can now implement more transport protocols to transport SCMI
messages.

The transport protocols just need to provide struct scmi_transport_ops,
with its version of the callbacks to enable exchange of SCMI messages.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://lore.kernel.org/r/8698a3cec199b8feab35c2339f02dc232bfd773b.1580448239.git.viresh.kumar@linaro.org
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-02-10 11:50:51 +00:00
Viresh Kumar c4eb83660a firmware: arm_scmi: Move macros and helpers to common.h
Move message header specific macros and helper routines to common.h as
they will be used outside of driver.c in a later commit.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://lore.kernel.org/r/6615db480370719b0a0241447a5f3feb8eea421f.1580448239.git.viresh.kumar@linaro.org
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-02-10 11:50:47 +00:00
Viresh Kumar 71af05a7d0 firmware: arm_scmi: Update doc style comments
Fix minor formatting issues with the doc style comments.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://lore.kernel.org/r/1bff7c0d1ad2c8b6eeff9660421f414f8c612eb2.1580448239.git.viresh.kumar@linaro.org
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-02-10 11:50:41 +00:00
Lukasz Luba 729d3530a5 drivers: firmware: scmi: Extend SCMI transport layer by trace events
The SCMI transport layer communicates via mailboxes and shared memory with
firmware running on a microcontroller. It is platform specific how long it
takes to pass a SCMI message. The most sensitive requests are coming from
CPUFreq subsystem, which might be used by the scheduler.
Thus, there is a need to measure these delays and capture anomalies.
This change introduces trace events wrapped around transfer code.

According to Jim's suggestion a unique transfer_id is to distinguish
similar entries which might have the same message id, protocol id and
sequence. This is a case then there are some timeouts in transfers.

Suggested-by: Jim Quinlan <james.quinlan@broadcom.com>
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2019-12-30 12:34:37 +00:00
Sudeep Holla aa90ac45bc firmware: arm_scmi: Use {get,put}_unaligned_le{32,64} accessors
Instead of type-casting the {tx,rx}.buf all over the place while
accessing them to read/write __le{32,64} from/to the firmware, let's
use the existing {get,put}_unaligned_le{32,64} accessors to hide all
the type cast ugliness.

Suggested-by: Philipp Zabel <p.zabel@pengutronix.de>
Reviewed-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2019-08-12 12:23:01 +01:00
Sudeep Holla 58ecdf03db firmware: arm_scmi: Add support for asynchronous commands and delayed response
Messages that are sent to platform, also known as commands and can be:

1. Synchronous commands that block the channel until the requested work
has been completed. The platform responds to these commands over the
same channel and hence can't be used to send another command until the
previous command has completed.

2. Asynchronous commands on the other hand, the platform schedules the
requested work to complete later in time and returns almost immediately
freeing the channel for new commands. The response indicates the success
or failure in the ability to schedule the requested work. When the work
has completed, the platform sends an additional delayed response message.

Using the same transmit buffer used for sending the asynchronous command
even for the delayed response corresponding to it simplifies handling of
the delayed response. It's the caller of asynchronous command that is
responsible for allocating the completion flag that scmi driver can
complete to indicate the arrival of delayed response.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2019-08-12 12:23:00 +01:00
Sudeep Holla 5b65af8f60 firmware: arm_scmi: Use the term 'message' instead of 'command'
In preparation to adding support for other two types of messages that
SCMI specification mentions, let's replace the term 'command' with the
correct term 'message'.

As per the specification the messages are of 3 types:
commands(synchronous or asynchronous), delayed responses and notifications.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2019-08-12 12:22:58 +01:00
Nishad Kamdar d252768216 firmware: arm_scmi: Use the correct style for SPDX License Identifier
This patch corrects the SPDX License Identifier style
in header file related to Firmware Drivers for ARM SCMI
Message Protocol.
For C header files Documentation/process/license-rules.rst
mandates C-like comments (opposed to C source files where
C++ style should be used)

Changes made by using a script provided by Joe Perches here:
https://lkml.org/lkml/2019/2/7/46

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Nishad Kamdar <nishadkamdar@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 19:32:31 +02:00
Sudeep Holla 97b93dda31 firmware: arm_scmi: drop unused `con_priv` structure member
Initially con_priv was supposedly used for transport specific data when
the SCMI driver had an abstraction to communicate with different mailbox
controllers. But after some discussions, the idea was dropped but this
variable slipped through the cracks.

This patch gets rid of this unused variable.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2018-05-10 10:51:58 +01:00
Sudeep Holla 14e297b3b8 firmware: arm_scmi: rename scmi_xfer_{init,get,put}
Just after the initial patches were queued, Jonathan Cameron mentioned
that scmi_one_xfer_{get_put} were not very clear and suggested to use
scmi_xfer_{alloc,free}. While I agree to some extent, the reason not to
have alloc/free as these are preallocated buffers and these functions
just returns a reference to free slot in that preallocated array.
However it was agreed to drop "_one" as it's implicit that we are always
dealing with one slot anyways.

This patch updates the name accordingly dropping "_one" in both {get,put}
functions. Also scmi_one_xfer_init is renamed as scmi_xfer_get_init to
reflect the fact that it gets the free slots and then initialise it.

Reported-by: Jonathan Cameron <jonathan.cameron@huawei.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2018-05-10 10:51:57 +01:00
Sudeep Holla 1baf47c2e5 firmware: arm_scmi: fix kernel-docs documentation
There are few missing descriptions for function parameters and structure
members along with certain instances where excessive function parameters
or structure members are described.

This patch fixes all of those warnings.

Reported-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2018-05-09 17:52:06 +01:00
Sudeep Holla 354b2e36d7 firmware: arm_scmi: improve code readability using bitfield accessor macros
By using FIELD_{FIT,GET,PREP} and GENMASK macro accessors we can avoid
some clumpsy custom shifting and masking macros and also improve the
code better readability.

Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2018-05-09 17:52:06 +01:00
Sudeep Holla a9e3fbfaa0 firmware: arm_scmi: add initial support for performance protocol
The performance protocol is intended for the performance management of
group(s) of device(s) that run in the same performance domain. It
includes even the CPUs. A performance domain is defined by a set of
devices that always have to run at the same performance level.
For example, a set of CPUs that share a voltage domain, and have a
common frequency control, is said to be in the same performance domain.

The commands in this protocol provide functionality to describe the
protocol version, describe various attribute flags, set and get the
performance level of a domain. It also supports discovery of the list
of performance levels supported by a performance domain, and the
properties of each performance level.

This patch adds basic support for the performance protocol.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2018-02-28 16:37:57 +00:00
Sudeep Holla 933c504424 firmware: arm_scmi: add scmi protocol bus to enumerate protocol devices
The SCMI specification encompasses various protocols. However, not every
protocol has to be present on a given platform/implementation as not
every protocol is relevant for it.

Furthermore, the platform chooses which protocols it exposes to a given
agent. The only protocol that must be implemented is the base protocol.
The base protocol is used by an agent to discover which protocols are
available to it.

In order to enumerate the discovered implemented protocols, this patch
adds support for a separate scmi protocol bus. It also adds mechanism to
register support for different protocols.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2018-02-28 16:37:57 +00:00
Sudeep Holla b6f20ff8bd firmware: arm_scmi: add common infrastructure and support for base protocol
The base protocol describes the properties of the implementation and
provide generic error management. The base protocol provides commands
to describe protocol version, discover implementation specific
attributes and vendor/sub-vendor identification, list of protocols
implemented and the various agents are in the system including OSPM
and the platform. It also supports registering for notifications of
platform errors.

This protocol is mandatory. This patch adds support for the same along
with some basic infrastructure to add support for other protocols.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2018-02-28 16:37:57 +00:00
Sudeep Holla aa4f886f38 firmware: arm_scmi: add basic driver infrastructure for SCMI
The SCMI is intended to allow OSPM to manage various functions that are
provided by the hardware platform it is running on, including power and
performance functions. SCMI provides two levels of abstraction, protocols
and transports. Protocols define individual groups of system control and
management messages. A protocol specification describes the messages
that it supports. Transports describe the method by which protocol
messages are communicated between agents and the platform.

This patch adds basic infrastructure to manage the message allocation,
initialisation, packing/unpacking and shared memory management.

Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2018-02-28 16:37:57 +00:00