Commit graph

88 commits

Author SHA1 Message Date
Cristian Marussi
c0397c85b5 firmware: arm_scmi: Use WARN_ON() to check configured transports
Use a WARN_ON() when SCMI stack is loaded to check the consistency of
configured SCMI transports instead of the current compile-time check
BUILD_BUG_ON() to avoid breaking bot-builds on random bad configs.

Bail-out early and noisy during SCMI stack initialization if no transport
was enabled in configuration since SCMI cannot work without at least one
enabled transport and such constraint cannot be enforced in Kconfig due to
circular dependency issues.

Link: https://lore.kernel.org/r/20210809092245.8730-1-cristian.marussi@arm.com
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-08-09 11:43:32 +01:00
Rishabh Bhatnagar
1e7cbfaa66 firmware: arm_scmi: Free mailbox channels if probe fails
Mailbox channels for the base protocol are setup during probe.
There can be a scenario where probe fails to acquire the base
protocol due to a timeout leading to cleaning up of all device
managed memory including the scmi_mailbox structure setup during
mailbox_chan_setup function.

    | arm-scmi soc:qcom,scmi: timed out in resp(caller: version_get+0x84/0x140)
    | arm-scmi soc:qcom,scmi: unable to communicate with SCMI
    | arm-scmi: probe of soc:qcom,scmi failed with error -110

Now when a message arrives at cpu slightly after the timeout, the mailbox
controller will try to call the rx_callback of the client and might end
up accessing freed memory.

     | rx_callback+0x24/0x160
     | mbox_chan_received_data+0x44/0x94
     | __handle_irq_event_percpu+0xd4/0x240

This patch frees the mailbox channels setup during probe and adds some more
error handling in case the probe fails.

Link: https://lore.kernel.org/r/1628111999-21595-1-git-send-email-rishabhb@codeaurora.org
Tested-by: Cristian Marussi <cristian.marussi@arm.com>
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Rishabh Bhatnagar <rishabhb@codeaurora.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-08-05 11:57:03 +01:00
Igor Skalkin
46abe13b5e firmware: arm_scmi: Add virtio transport
This transport enables communications with an SCMI platform through virtio;
the SCMI platform will be represented by a virtio device.

Implement an SCMI virtio driver according to the virtio SCMI device spec
[1]. Virtio device id 32 has been reserved for the SCMI device [2].

The virtio transport has one Tx channel (virtio cmdq, A2P channel) and
at most one Rx channel (virtio eventq, P2A channel).

The following feature bit defined in [1] is not implemented:
VIRTIO_SCMI_F_SHARED_MEMORY.

The number of messages which can be pending simultaneously is restricted
according to the virtqueue capacity negotiated at probing time.

As soon as Rx channel message buffers are allocated or have been read
out by the arm-scmi driver, feed them back to the virtio device.

Since some virtio devices may not have the short response time exhibited
by SCMI platforms using other transports, set a generous response
timeout.

SCMI polling mode is not supported by this virtio transport since deemed
meaningless: polling mode operation is offered by the SCMI core to those
transports that could not provide a completion interrupt on the TX path,
which is never the case for virtio whose core callbacks can easily call
into core scmi_rx_callback upon messages reception.

[1] https://github.com/oasis-tcs/virtio-spec/blob/master/virtio-scmi.tex
[2] https://www.oasis-open.org/committees/ballot.php?id=3496

Link: https://lore.kernel.org/r/20210803131024.40280-16-cristian.marussi@arm.com
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Co-developed-by: Peter Hilber <peter.hilber@opensynergy.com>
Co-developed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Igor Skalkin <igor.skalkin@opensynergy.com>
[ Peter: Adapted patch for submission to upstream. ]
Signed-off-by: Peter Hilber <peter.hilber@opensynergy.com>
[ Cristian: simplified driver logic, changed link_supplier and channel
	    available/setup logic, removed dummy callbacks ]
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-08-05 10:24:08 +01:00
Cristian Marussi
13fba878cc firmware: arm_scmi: Add priv parameter to scmi_rx_callback
Add a new opaque void *priv parameter to scmi_rx_callback which can be
optionally provided by the transport layer when invoking scmi_rx_callback
and that will be passed back to the transport layer in xfer->priv.

This can be used by transports that needs to keep track of their specific
data structures together with the valid xfers.

Link: https://lore.kernel.org/r/20210803131024.40280-15-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-08-05 10:23:23 +01:00
Peter Hilber
7885281260 firmware: arm_scmi: Add optional link_supplier() transport op
Some transports are also effectively registered with other kernel subsystem
in order to be properly probed and initialized; as a consequence such kind
of transports, and their related devices, might still not have been probed
and initialized at the time the main SCMI core driver is probed.

Add an optional .link_supplier() transport operation which can be used by
the core SCMI stack to dynamically check if the transport is ready and
dynamically link its device to the SCMI platform instance device.

Link: https://lore.kernel.org/r/20210803131024.40280-13-cristian.marussi@arm.com
Signed-off-by: Peter Hilber <peter.hilber@opensynergy.com>
[ Cristian: reworded commit message ]
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-08-05 10:23:23 +01:00
Igor Skalkin
c92c3e382e firmware: arm_scmi: Add method to override max message number
The maximum number of simultaneously pending messages is a transport
specific quantity that is usually described statically in struct scmi_desc.

Some transports, though, can calculate such number only at run-time after
some initial transport specific setup and probing is completed; moreover
the resulting max message numbers could also be different between rx and
tx channels.

Add an optional get_max_msg() operation so that a transport can report more
accurate max message numbers for each channel type.

The value in scmi_desc.max_msg is still used as default when transport does
not provide any get_max_msg() method.

Link: https://lore.kernel.org/r/20210803131024.40280-11-cristian.marussi@arm.com
Co-developed-by: Peter Hilber <peter.hilber@opensynergy.com>
Co-developed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Igor Skalkin <igor.skalkin@opensynergy.com>
[ Peter: Adapted patch for submission to upstream. ]
Signed-off-by: Peter Hilber <peter.hilber@opensynergy.com>
[ Cristian: refactored how get_max_msg() is used to minimize core changes ]
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-08-05 10:23:23 +01:00
Cristian Marussi
e8419c24ba firmware: arm_scmi: Make SCMI transports configurable
Add configuration options to be able to select which SCMI transports have
to be compiled into the SCMI stack.

Mailbox and SMC are by default enabled if their related dependencies are
satisfied.

While doing that move all SCMI related config options in their own
dedicated submenu.

Link: https://lore.kernel.org/r/20210803131024.40280-9-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-08-05 10:23:22 +01:00
Cristian Marussi
2930abcffd firmware: arm_scmi: Make polling mode optional
Add a check for the presence of .poll_done transport operation so that
transports that do not need to support polling mode have no need to provide
a dummy .poll_done callback either and polling mode can be disabled in the
SCMI core for that tranport.

Link: https://lore.kernel.org/r/20210803131024.40280-8-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-08-05 10:23:22 +01:00
Cristian Marussi
e9b21c9618 firmware: arm_scmi: Make .clear_channel optional
Make transport operation .clear_channel optional since some transports
do not need it and so avoid to have them implement dummy callbacks.

Link: https://lore.kernel.org/r/20210803131024.40280-7-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-08-05 10:23:22 +01:00
Cristian Marussi
ed7c04c1fe firmware: arm_scmi: Handle concurrent and out-of-order messages
Even though in case of asynchronous commands an SCMI platform is
constrained to emit the delayed response message only after the related
message response has been sent, the configured underlying transport could
still deliver such messages together or in inverted order, causing races
due to the concurrent or out-of-order access to the underlying xfer.

Introduce a mechanism to grant exclusive access to an xfer in order to
properly serialize concurrent accesses to the same xfer originating from
multiple correlated messages.

Add additional state information to xfer descriptors so as to be able to
identify out-of-order message deliveries and act accordingly:

 - when a delayed response is expected but delivered before the related
   response, the synchronous response is considered as successfully
   received and the delayed response processing is carried on as usual.

 - when/if the missing synchronous response is subsequently received, it
   is discarded as not congruent with the current state of the xfer, or
   simply, because the xfer has been already released and so, now, the
   monotonically increasing sequence number carried by the late response
   is stale.

Link: https://lore.kernel.org/r/20210803131024.40280-6-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-08-05 10:23:22 +01:00
Cristian Marussi
9ca5a1838e firmware: arm_scmi: Introduce monotonically increasing tokens
Tokens are sequence numbers embedded in the each SCMI message header: they
are used to correlate commands with responses (and delayed responses), but
their usage and policy of selection is entirely up to the caller (usually
the OSPM agent), while they are completely opaque to the callee (i.e. SCMI
platform) which merely copies them back from the command into the response
message header.
This also means that the platform does not, can not and should not enforce
any kind of policy on received messages depending on the contained sequence
number: platform can perfectly handle concurrent requests carrying the same
identifiying token if that should happen.

Moreover the platform is not required to produce in-order responses to
agent requests, the only constraint in these regards is that in case of
an asynchronous message the delayed response must be sent after the
immediate response for the synchronous part of the command transaction.

Currenly the SCMI stack of the OSPM agent selects a token for the egressing
commands picking the lowest possible number which is not already in use by
an existing in-flight transaction, which means, in other words, that we
immediately reuse any token after its transaction has completed or it has
timed out: this policy indeed does simplify management and lookup of tokens
and associated xfers.

Under the above assumptions and constraints, since there is really no state
shared between the agent and the platform to let the platform know when a
token and its associated message has timed out, the current policy of early
reuse of tokens can easily lead to the situation in which a spurious or
late received response (or delayed_response), related to an old stale and
timed out transaction, can be wrongly associated to a newer valid in-flight
xfer that just happens to have reused the same token.

This misbehaviour on such late/spurious responses is more easily exposed on
those transports that naturally have an higher level of parallelism in
processing multiple concurrent in-flight messages.

This commit introduces a new policy of selection of tokens for the OSPM
agent: each new command transfer now gets the next available, monotonically
increasing token, until tokens are exhausted and the counter rolls over.

Such new policy mitigates the above issues with late/spurious responses
since the tokens are now reused as late as possible (when they roll back
ideally) and so it is much easier to identify such late/spurious responses
to stale timed out transactions: this also helps in simplifying the
specific transports implementation since stale transport messages can be
easily identified and discarded early on in the rx path without the need
to cross check their actual state with the core transport layer.
This mitigation is even more effective when, as is usually the case, the
maximum number of pending messages is capped by the platform to a much
lower number than the whole possible range of tokens values (2^10).

This internal policy change in the core SCMI transport layer is fully
transparent to the specific transports so it has not and should not have
any impact on the transports implementation.

Link: https://lore.kernel.org/r/20210803131024.40280-5-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-08-05 10:23:22 +01:00
Cristian Marussi
ceac257db0 firmware: arm_scmi: Add optional transport_init/exit support
Some SCMI transport could need to perform some transport specific setup
before they can be used by the SCMI core transport layer: typically this
early setup consists in registering with some other kernel subsystem.

Add the optional capability for a transport to provide a couple of init
and exit functions that are assured to be called early during the SCMI
core initialization phase, well before the SCMI core probing step.

[ Peter: Adapted RFC patch by Cristian for submission to upstream. ]

Link: https://lore.kernel.org/r/20210803131024.40280-4-cristian.marussi@arm.com
Signed-off-by: Peter Hilber <peter.hilber@opensynergy.com>
[ Cristian: Fixed scmi_transports_exit point of invocation ]
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-08-05 10:23:22 +01:00
Cristian Marussi
3669032514 firmware: arm_scmi: Remove scmi_dump_header_dbg() helper
Being a while that we have SCMI trace events in the SCMI stack, remove
this debug helper and its call sites.

Link: https://lore.kernel.org/r/20210803131024.40280-3-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-08-05 10:23:22 +01:00
Cristian Marussi
63b282f172 firmware: arm_scmi: Add support for type handling in common functions
Add SCMI type handling to pack/unpack_scmi_header common helper functions.
Initialize hdr.type properly when initializing a command xfer.

Link: https://lore.kernel.org/r/20210803131024.40280-2-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-08-05 10:23:21 +01:00
Cristian Marussi
bdb8742dc6 firmware: arm_scmi: Fix range check for the maximum number of pending messages
SCMI message headers carry a sequence number and such field is sized to
allow for MSG_TOKEN_MAX distinct numbers; moreover zero is not really an
acceptable maximum number of pending in-flight messages.

Fix accordingly the checks performed on the value exported by transports
in scmi_desc.max_msg

Link: https://lore.kernel.org/r/20210712141833.6628-3-cristian.marussi@arm.com
Reported-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
[sudeep.holla: updated the patch title and error message]
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-07-13 11:42:20 +01:00
Cristian Marussi
b98cf55ec0 firmware: arm_scmi: Fix kernel doc warnings about return values
Kernel doc validation script still complains about the following:

|No description found for return value of 'scmi_get_protocol_device'
|No description found for return value of 'scmi_devm_notifier_register'
|No description found for return value of 'scmi_devm_notifier_unregister'

Fix adding missing Return kernel-doc statements.

Link: https://lore.kernel.org/r/20210712143504.33541-1-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-07-13 11:39:54 +01:00
Sudeep Holla
7a691f16cc firmware: arm_scmi: Fix possible scmi_linux_errmap buffer overflow
The scmi_linux_errmap buffer access index is supposed to depend on the
array size to prevent element out of bounds access. It uses SCMI_ERR_MAX
to check bounds but that can mismatch with the array size. It also
changes the success into -EIO though scmi_linux_errmap is never used in
case of success, it is expected to work for success case too.

It is slightly confusing code as the negative of the error code
is used as index to the buffer. Fix it by negating it at the start and
make it more readable.

Link: https://lore.kernel.org/r/20210707135028.1869642-1-sudeep.holla@arm.com
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-07-12 14:16:19 +01:00
Sudeep Holla
61832b35b4 firmware: arm_scmi: Avoid multiple initialisations of hdr->protocol_id
Since the hdr->protocol_id is set from the scmi_protocol_instance handle
just before the transfer, there is no need to initialise the same in
scmi_xfer_get_init. Remove the unnecessary initialisations.

Link: https://lore.kernel.org/r/20210608140140.2042257-1-sudeep.holla@arm.com
Tested-by: Cristian Marussi <cristian.marussi@arm.com>
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-06-08 16:06:12 +01:00
Cristian Marussi
e30d91d4ff firmware: arm_scmi: Move reinit_completion from scmi_xfer_get to do_xfer
Re-using timed out xfers in a loop can lead to issue if completion was
not properly reinitialized. Move reinit_completion from scmi_xfer_get to
do_xfer to avoid the issue.

Link: https://lore.kernel.org/r/20210606221232.33768-3-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
[sudeep.holla: moved reinit_completion instead of adding another one]
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-06-08 16:04:54 +01:00
Cristian Marussi
f1748b1ee1 firmware: arm_scmi: Add delayed response status check
A successfully received delayed response could anyway report a failure at
the protocol layer in the message status field.

Add a check also for this error condition.

Link: https://lore.kernel.org/r/20210608103056.3388-1-cristian.marussi@arm.com
Fixes: 58ecdf03db ("firmware: arm_scmi: Add support for asynchronous commands and delayed response")
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-06-08 15:10:14 +01:00
Sudeep Holla
ab7766b728 firmware: arm_scmi: Fix the build when CONFIG_MAILBOX is not selected
0day CI kernel test robot reported following build error with randconfig

aarch64-linux-ld: drivers/firmware/arm_scmi/driver.o:(.rodata+0x1e0):
		undefined reference to `scmi_mailbox_desc'

Fix the error by adding CONFIG_MAILBOX dependency for scmi_mailbox_desc.

Link: https://lore.kernel.org/r/20210603072631.1660963-1-sudeep.holla@arm.com
Cc: Etienne Carriere <etienne.carriere@linaro.org>
Cc: Cristian Marussi <cristian.marussi@arm.com>
Reviewed-by: Etienne Carriere <etienne.carriere@linaro.org>
Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Tested-by: Cristian Marussi <cristian.marussi@arm.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-06-03 16:46:41 +01:00
Cristian Marussi
0cb7af474e firmware: arm_scmi: Reset Rx buffer to max size during async commands
During an async commands execution the Rx buffer length is at first set
to max_msg_sz when the synchronous part of the command is first sent.
However once the synchronous part completes the transport layer waits
for the delayed response which will be processed using the same xfer
descriptor initially allocated. Since synchronous response received at
the end of the xfer will shrink the Rx buffer length to the effective
payload response length, it needs to be reset again.

Raise the Rx buffer length again to max_msg_sz before fetching the
delayed response to ensure full response is read correctly from the
shared memory.

Link: https://lore.kernel.org/r/20210601102421.26581-2-cristian.marussi@arm.com
Fixes: 58ecdf03db ("firmware: arm_scmi: Add support for asynchronous commands and delayed response")
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
[sudeep.holla: moved reset to scmi_handle_response as it could race with
               do_xfer_with_response]
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-06-02 21:50:12 +01:00
Cristian Marussi
d4f9dddd21 firmware: arm_scmi: Add dynamic scmi devices creation
Having added the support for SCMI protocols as modules in order to let
vendors extend the SCMI core with their own additions it seems odd to
then force SCMI drivers built on top to use a static device table to
declare their devices since this way any new SCMI drivers addition
would need the core SCMI device table to be updated too.

Remove the static core device table and let SCMI drivers to simply declare
which device/protocol pair they need at initialization time: the core will
then take care to generate such devices dynamically during platform
initialization or at module loading time, as long as the requested
underlying protocol is defined in the devicetree.

Link: https://lore.kernel.org/r/20210316124903.35011-39-cristian.marussi@arm.com
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-03-30 16:35:16 +01:00
Cristian Marussi
f5800e0bf6 firmware: arm_scmi: Add protocol modularization support
Extend SCMI protocols accounting mechanism to address possible module
usage and add the support to possibly define new protocols as loadable
modules.

Keep the standard protocols built into the SCMI core.

Link: https://lore.kernel.org/r/20210316124903.35011-38-cristian.marussi@arm.com
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-03-30 16:35:16 +01:00
Cristian Marussi
a02d7c93c1 firmware: arm_scmi: Make notify_priv really private
Notification private data is currently accessible via handle->notify_priv,
this data was indeed meant to be private to the notification core support
and not to be accessible by SCMI drivers. Make it private hiding it
inside instance descriptor struct scmi_info and accessible only via
dedicated helpers.

Link: https://lore.kernel.org/r/20210316124903.35011-36-cristian.marussi@arm.com
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-03-30 16:35:15 +01:00
Cristian Marussi
9162afa2ae firmware: arm_scmi: Cleanup unused core transfer helper wrappers
Remove unused core scmi_xfer wrappers now that we have migrated all
protocols to the new interface based on protocol handles.

Link: https://lore.kernel.org/r/20210316124903.35011-34-cristian.marussi@arm.com
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-03-30 16:35:15 +01:00
Cristian Marussi
f0e73cee26 firmware: arm_scmi: Make references to handle const
Now that all the protocol private variable data have been moved out of
struct scmi_handle, mark all of its references as const.

Link: https://lore.kernel.org/r/20210316124903.35011-32-cristian.marussi@arm.com
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-03-30 16:35:15 +01:00
Cristian Marussi
8d3581c252 firmware: arm_scmi: Port base protocol to new interface
Port the SCMI base protocol to new protocol handles based interface.

Link: https://lore.kernel.org/r/20210316124903.35011-11-cristian.marussi@arm.com
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-03-29 10:00:35 +01:00
Cristian Marussi
3d5d6e84ea firmware: arm_scmi: Add helper to access protocol revision/version
Add an helper to access from a protocol handle, the SCMI version data
which is exposed on sysfs. Such helper will be needed by SCMI base
protocol initialization once it will be moved to new protocol handles
scheme.

Link: https://lore.kernel.org/r/20210316124903.35011-10-cristian.marussi@arm.com
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-03-29 10:00:35 +01:00
Cristian Marussi
a4a20b0975 firmware: arm_scmi: Add new protocol handle core transfer ops
Add new core SCMI transfer operations based on protocol handles to
enable protocols to builds and send their own protocol specific messages.

Keep old original scmi_xfer_ operations interface as wrappers around the
new interface in order to let coexist old and new interfaces to ease
protocol by protocol migration.

In order to support such migration the above wrappers and some
additional transient code is also introduced in this commit. It will be
later removed as a whole once the full migration of protocols and SCMI
drivers will have been completed.

Link: https://lore.kernel.org/r/20210316124903.35011-9-cristian.marussi@arm.com
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-03-29 10:00:35 +01:00
Cristian Marussi
b9f7fd907c firmware: arm_scmi: Convert events registration to protocol handles
Convert all refactored events registration routines to use protocol
handles.

In order to maintain bisectability and to allow protocols and drivers
to be later ported to the new protocol handle interface one by one,
introduce here also some transient code that will be removed later
in order to ease such transition.

Link: https://lore.kernel.org/r/20210316124903.35011-8-cristian.marussi@arm.com
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-03-29 10:00:35 +01:00
Cristian Marussi
533c7095b1 firmware: arm_scmi: Refactor events registration
Add a new refactored protocol events registration helper and invoke it
from the centralized initialization process triggered by get_ops() and
friends.

Also add a `get_num_sources` as a new optional callback amongst protocol
events operations. Finally remove events registration call-sites from
within the legacy protocol init routines.

Link: https://lore.kernel.org/r/20210316124903.35011-7-cristian.marussi@arm.com
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-03-29 10:00:35 +01:00
Cristian Marussi
23934efe37 firmware: arm_scmi: Introduce devres get/put protocols operations
Expose to the SCMI drivers a new devres managed common protocols API
based on generic get/put methods and protocol handles.

All drivers still keep using the old API, no functional change.

Link: https://lore.kernel.org/r/20210316124903.35011-4-cristian.marussi@arm.com
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-03-29 10:00:16 +01:00
Cristian Marussi
d7b6cc563a firmware: arm_scmi: Introduce protocol handle definitions
Add basic protocol handles definitions and private data helpers.

A protocol handle identifies a protocol instance initialized against a
specific handle, it embeds all the references to the core SCMI transfer
methods that will be needed by a protocol implementation to build and
send its own protocol specific messages using common core methods.

As such, in the interface, a protocol handle will be passed down from
the core to the protocol specific initialization callback at init time.

Anyways, at this point only definitions are introduced, all protocols
initialization code and SCMI drivers probing is still based on the old
interface, so no functional change.

Link: https://lore.kernel.org/r/20210316124903.35011-3-cristian.marussi@arm.com
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-03-29 09:41:29 +01:00
Cristian Marussi
48dc16e2e5 firmware: arm_scmi: Extend protocol registration interfaces
Extend common protocol registration routines and provide some new generic
protocols get/put helpers that can track protocols usage and automatically
perform the proper initialization and de-initialization on demand when
required.

Convert all standard protocols to use this new registration scheme while
keeping them all still using the usual initialization logic bound to SCMI
devices probing.

Link: https://lore.kernel.org/r/20210316124903.35011-2-cristian.marussi@arm.com
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-03-29 09:40:47 +01:00
Jyoti Bhayana
f774117c96 iio/scmi: Adding support for IIO SCMI Based Sensors
This change provides ARM SCMI Protocol based IIO device.
This driver provides support for Accelerometer and Gyroscope using
SCMI Sensor Protocol extensions added in the SCMIv3.0 ARM specification

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Jyoti Bhayana <jbhayana@google.com>
Link: https://lore.kernel.org/r/20210212172235.507028-2-jbhayana@google.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Link: https://lore.kernel.org/r/20210309231259.78050-2-jbhayana@google.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2021-03-13 16:43:04 +00:00
Cristian Marussi
a90b6543bf firmware: arm_scmi: Fix call site of scmi_notification_exit
Call scmi_notification_exit() only when SCMI platform driver instance has
been really successfully removed.

Link: https://lore.kernel.org/r/20210112191326.29091-1-cristian.marussi@arm.com
Fixes: 6b8a69131d ("firmware: arm_scmi: Enable notification core")
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
[sudeep.holla: Move the call outside the list mutex locking]
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-01-13 14:30:16 +00:00
Cristian Marussi
ec88381936 firmware: arm_scmi: Add support to enumerated SCMI voltage domain device
Add SCMI voltage domain device name to the core list of supported protocol
devices so that it can be enumerated if the firmware supports it.

Link: https://lore.kernel.org/r/20201119191051.46363-3-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-11-20 14:55:48 +00:00
Cristian Marussi
2add5cacff firmware: arm_scmi: Add voltage domain management protocol support
SCMI v3.0 introduces voltage domain protocol which provides commands to:
 - Discover the voltage levels supported by a domain
 - Get the configuration and voltage level of a domain
 - Set the configuration and voltage level of a domain

Let us add support for the same.

Link: https://lore.kernel.org/r/20201119191051.46363-2-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-11-20 14:55:48 +00:00
Sudeep Holla
9724722fde firmware: arm_scmi: Add missing Rx size re-initialisation
Few commands provide the list of description partially and require
to be called consecutively until all the descriptors are fetched
completely. In such cases, we don't release the buffers and reuse
them for consecutive transmits.

However, currently we don't reset the Rx size which will be set as
per the response for the last transmit. This may result in incorrect
response size being interpretted as the firmware may repond with size
greater than the one set but we read only upto the size set by previous
response.

Let us reset the receive buffer size to max possible in such cases as
we don't know the exact size of the response.

Link:  https://lore.kernel.org/r/20201012141746.32575-1-sudeep.holla@arm.com
Fixes: b6f20ff8bd ("firmware: arm_scmi: add common infrastructure and support for base protocol")
Reported-by: Etienne Carriere <etienne.carriere@linaro.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-10-13 10:01:47 +01:00
Sudeep Holla
1eaf18e35a firmware: arm_scmi: Move scmi protocols registration into the driver
In preparation to enable building SCMI as a single module, let us move
the SCMI protocol registration call into the driver. This enables us
to also add unregistration of the SCMI protocols.

The main reason for this is to keep it simple instead of maintaining
it as separate modules and dealing with all possible initcall races
and deferred probe handling. We can move it as separate modules if
needed in future.

Link: https://lore.kernel.org/r/20200907195046.56615-4-sudeep.holla@arm.com
Tested-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-09-14 07:30:55 +01:00
Sudeep Holla
5a2f0a0bdf firmware: arm_scmi: Move scmi bus init and exit calls into the driver
In preparation to enable building scmi as a single module, let us move
the scmi bus {de-,}initialisation call into the driver.

The main reason for this is to keep it simple instead of maintaining
it as separate modules and dealing with all possible initcall races
and deferred probe handling. We can move it as separate modules if
needed in future.

Link: https://lore.kernel.org/r/20200907195046.56615-3-sudeep.holla@arm.com
Tested-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-09-14 07:30:48 +01:00
Cristian Marussi
481f6ccf39 firmware: arm_scmi: Add SCMI device for system power protocol
Add SCMI device for system power protocol by just adding the name "syspower"
to the list of supported core protocol devices.

Link: https://lore.kernel.org/r/20200907174657.32466-3-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-09-08 16:02:17 +01:00
Cristian Marussi
72a5eb9d9c firmware: arm_scmi: Remove fixed size fields from reports/scmi_event_header
Event reports are used to convey information describing events to the
registered user-callbacks: they are necessarily derived from the underlying
raw SCMI events' messages but they are not meant to expose or directly
mirror any of those messages data layout, which belong to the protocol
layer.

Using fixed size types for report fields, mirroring messages structure,
is at odd with this: get rid of them using more generic, equivalent,
typing.

Substitute scmi_event_header fixed size fields with generic types too and
shuffle around fields definitions to minimize implicit padding while
adapting involved functions.

Link: https://lore.kernel.org/r/20200710133919.39792-3-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-07-13 09:40:21 +01:00
Cristian Marussi
6b8a69131d firmware: arm_scmi: Enable notification core
Initialize and enable SCMI notifications core support during bus/driver
probe phase, so that protocols can start registering their supported
events during their initialization.

Link: https://lore.kernel.org/r/20200701155348.52864-5-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 17:07:26 +01:00
Sudeep Holla
d764282377 firmware: arm_scmi: Use HAVE_ARM_SMCCC_DISCOVERY instead of ARM_PSCI_FW
Commit e5bfb21d98 ("firmware: smccc: Add HAVE_ARM_SMCCC_DISCOVERY to
identify SMCCC v1.1 and above") introduced new config option to identify
the availability of SMCCC discoverability of version and features
transparently hiding the indirect dependency on ARM_PSCI_FW.

Commit 5a897e3ab4 ("firmware: arm_scmi: fix psci dependency") just
worked around the build dependency making SCMI SMC/HVC transport depend
on ARM_PSCI_FW at the time. Since it really just relies on SMCCC directly
and not on ARM_PSCI_FW, let us move to use CONFIG_HAVE_ARM_SMCCC_DISCOVERY
instead of CONFIG_ARM_PSCI_FW.

Link: https://lore.kernel.org/r/20200625101937.51939-1-sudeep.holla@arm.com
Cc: Peng Fan <peng.fan@nxp.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-06-30 14:08:10 +01:00
Sudeep Holla
bad0d73b65 firmware: arm_scmi: Use signed integer to report transfer status
Currently the trace event 'scmi_xfer_end' reports the status of the
transfer using the unsigned status field read from the firmware which
may not be easy to interpret. It may also miss to emit any timeouts
that happen in the driver resulting in emitting garbage in the status
field in those scenarios.

Let us use signed integer so that error values are emitted out after
they are mapped from firmware error formats to standard linux error
codes. While at this, also include any timeouts in the driver itself.

Link: https://lore.kernel.org/r/20200609134503.55860-1-sudeep.holla@arm.com
Cc: Jim Quinlan <james.quinlan@broadcom.com>
Cc: Lukasz Luba <lukasz.luba@arm.com>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-06-30 14:07:08 +01:00
Sudeep Holla
5a897e3ab4 firmware: arm_scmi: fix psci dependency
When CONFIG_ARM_PSCI_FW is disabled but CONFIG_HAVE_ARM_SMCCC is enabled,
arm-scmi runs into a link failure:

arm-linux-gnueabi-ld: drivers/firmware/arm_scmi/smc.o: in function `smc_send_message':
smc.c:(.text+0x200): undefined reference to `arm_smccc_1_1_get_conduit'

Change from HAVE_ARM_SMCCC to ARM_PSCI_FW config dependency for now.
We rely on PSCI bindings anyways for the conduit and this should be
fine.

Link: https://lore.kernel.org/r/20200507144905.11397-1-sudeep.holla@arm.com
Fixes: 1dc6558062 ("firmware: arm_scmi: Add smc/hvc transport")
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-05-07 16:28:56 +01:00
Cristian Marussi
c5bceb98ce firmware: arm_scmi: Fix handling of unexpected delayed responses
Upon reception of an unexpected bogus delayed response, clear the channel
and bail-out safely.

Link: https://lore.kernel.org/r/20200420152315.21008-5-cristian.marussi@arm.com
Fixes: 4d09852b6f ("firmware: arm_scmi: Add support for notifications message processing")
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
d04fb2b2dd firmware: arm_scmi: Clear channel for delayed responses
Clear channel properly when done processing a delayed response.
This will let the platform firmware know that the channel is now free to
use it for any new delayed response or notification.

Link: https://lore.kernel.org/r/20200420152315.21008-4-cristian.marussi@arm.com
Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
(sudeep.holla: Updated commit log to reflect that channel is now free for
 platform to use)
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2020-04-20 17:25:26 +01:00