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path: root/drivers/firmware/arm_scmi/common.h
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2025-07-03include: trace: Add tracepoint support for inflight xfer countPhilip Radford
Enhance the existing SCMI transfer tracepoints by including the current in-flight transfer count in `scmi_xfer_begin` and `scmi_xfer_end`. Introduce a new helper `scmi_inflight_count()` to retrieve the active transfer count from the SCMI debug counters when debug is enabled. This trace data is useful for visualizing transfer activity over time and identifying congestion or unexpected behavior in SCMI messaging. Reviewed-by: Cristian Marussi <cristian.marussi@arm.com> Signed-off-by: Philip Radford <philip.radford@arm.com> Message-Id: <20250630105544.531723-4-philip.radford@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2025-07-03firmware: arm_scmi: Track number of inflight SCMI transfersPhilip Radford
Add a new debug counter, `XFERS_INFLIGHT`, to track the number of currently active in-flight SCMI message transfers. This helps in understanding system behavior and diagnosing potential issues with pending or stuck messages. The counter is incremented when a transfer is registered as in-flight, and decremented when it completes and is released. It is automatically added to debugfs for visibility through SCMI debugfs. Reviewed-by: Cristian Marussi <cristian.marussi@arm.com> Signed-off-by: Philip Radford <philip.radford@arm.com> Message-Id: <20250630105544.531723-3-philip.radford@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2025-07-03firmware: arm_scmi: Add support for debug counter decrementPhilip Radford
Introduce a new `scmi_dec_count` helper to complement the existing `scmi_inc_count`, allowing controlled decrement of SCMI debug counters. This provides symmetry in debug counter management and enables accurate tracking of counters that may both increase and decrease, such as those used for in-flight message tracking. Only active when CONFIG_ARM_SCMI_DEBUG_COUNTERS is enabled. Reviewed-by: Cristian Marussi <cristian.marussi@arm.com> Signed-off-by: Philip Radford <philip.radford@arm.com> Message-Id: <20250630105544.531723-2-philip.radford@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2025-04-14firmware: arm_scmi: Assign correct parent to arm-scmi platform deviceSudeep Holla
With the decoupling of transport drivers from the SCMI core, the "arm-scmi" platform device is now created dynamically from the probed transport driver. Currently, this "arm-scmi" platform device is added to the root of the platform bus since no parent is assigned. However, the transport platform device, created from the "firmware:scmi" node in the device tree, should be considered its parent. Ensure that the parent device is correctly set for the "arm-scmi" platform device, aligning it with the correct transport hierarchy. This will be more useful on systems with multiple transport and/or SCMI firmware instances as the hierarchy is maintained correctly. Message-Id: <20250317-b4-scmi_minor_cleanup-v2-4-f4be99bd9864@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2024-12-09firmware: arm_scmi: Allow transport properties for multiple instancesCristian Marussi
Default SCMI transport properties values can be overridden with devicetree provided descriptors; in order to support multiple SCMI instances, make the properties-update happen on a per-instance copy of the original transport descriptor. Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Message-Id: <20241203193544.3895173-1-cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2024-11-12Merge tag 'scmi-updates-6.13' of ↵Arnd Bergmann
https://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux into soc/drivers Arm SCMI updates for v6.13 Just couple of main additions: 1. Support for variable I/O width within ARM SCMI shared memory area. Some shared memory areas might only support a certain access width, such as 32-bit, which memcpy_{from,to}_io() does not adhere to at least on ARM64 by making both 8-bit and 64-bit accesses to such memory. This support updates the shmem layer to support reading from and writing to such shared memory area using the specified I/O width in the Device Tree. The various transport layers making use of the shmem.c code are updated accordingly to pass the I/O accessors that they store. The device tree bindings are also updated for the same. 2. Extension of SCMI transport bindings to add more properties SCMI transports are characterized by a number of properties. The values assumed by some of them tightly depend on the choices taken at design time and on the overall archiecture of the specific platform: things like timeouts, maximum message size and number of in-flight messages are closely tied to the architecture of the platform like number of SCMI agents on the system, physical memory available to the SCMI platform and so on. Such details are not discoverable as they are outside the scope of the SCMI protocol specification. Currently such properties are simple default values defined at build time, but the increasing number and variety of platforms using SCMI with a wide range of designs has increased the need to have a way to describe such properties across all these platforms. Apart from the above two, there is one NULL pointer dereference fix for very age old SCPI protocol driver which seems to be still in use on few platforms. * tag 'scmi-updates-6.13' of https://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux: firmware: arm_scpi: Check the DVFS OPP count returned by the firmware firmware: arm_scmi: Relocate atomic_threshold to scmi_desc firmware: arm_scmi: Use max_msg and max_msg_size devicetree properties dt-bindings: firmware: arm,scmi: Introduce more transport properties firmware: arm_scmi: Calculate virtio PDU max size dynamically firmware: arm_scmi: Account for SHMEM memory overhead firmware: arm_scmi: Support 'reg-io-width' property for shared memory dt-bindings: sram: Document reg-io-width property firmware: arm_scmi: Use vendor string in max-rx-timeout-ms dt-bindings: firmware: arm,scmi: Add missing vendor string firmware: arm_scmi: Reject clear channel request on A2P firmware: arm_scmi: Fix slab-use-after-free in scmi_bus_notifier() Link: https://lore.kernel.org/r/20241106110727.4007489-1-sudeep.holla@arm.com Signed-off-by: Arnd Bergmann <arnd@arndb.de>
2024-10-28firmware: arm_scmi: Relocate atomic_threshold to scmi_descCristian Marussi
Relocate the atomic_threshold field to scmi_desc and move the related code to scmi_transport_setup. No functional change. Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Message-Id: <20241028120151.1301177-6-cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2024-10-28firmware: arm_scmi: Account for SHMEM memory overheadCristian Marussi
Transports using shared memory have to consider the overhead due to the layout area when determining the area effectively available for messages. Till now, such definitions were ambiguos across the SCMI stack and the overhead layout area was not considered at all. Add proper checks in the shmem layer to validate the provided max_msg_size against the effectively available memory area, less the layout. Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Message-Id: <20241028120151.1301177-2-cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2024-10-28firmware: arm_scmi: Support 'reg-io-width' property for shared memoryFlorian Fainelli
Some shared memory areas might only support a certain access width, such as 32-bit, which memcpy_{from,to}_io() does not adhere to at least on ARM64 by making both 8-bit and 64-bit accesses to such memory. Update the shmem layer to support reading from and writing to such shared memory area using the specified I/O width in the Device Tree. The various transport layers making use of the shmem.c code are updated accordingly to pass the I/O accessors that they store. Signed-off-by: Florian Fainelli <florian.fainelli@broadcom.com> Message-Id: <20240827182450.3608307-3-florian.fainelli@broadcom.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2024-10-22firmware: arm_scmi: Reject clear channel request on A2PCristian Marussi
The clear channel transport operation is supposed to be called exclusively on the P2A channel from the agent, since it relinquishes the ownership of the channel to the platform, after this latter has initiated some sort of P2A communication. Make sure that, if it is ever called on a A2P, is logged and ignored. Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com> Message-Id: <20241021171544.2579551-1-cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2024-10-02move asm/unaligned.h to linux/unaligned.hAl Viro
asm/unaligned.h is always an include of asm-generic/unaligned.h; might as well move that thing to linux/unaligned.h and include that - there's nothing arch-specific in that header. auto-generated by the following: for i in `git grep -l -w asm/unaligned.h`; do sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i done for i in `git grep -l -w asm-generic/unaligned.h`; do sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i done git mv include/asm-generic/unaligned.h include/linux/unaligned.h git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h
2024-08-18firmware: arm_scmi: Remove const from transport descriptorsCristian Marussi
The descriptor structure scmi_desc contains a variety of fields related to the transport functionalities and it is defined by the transport drivers themselves; such elements, though, serve varied purposes and have different lifetime. In particular, while there are some of those elements that provide a description of transport features that are supposed to be immutable, on the other side there are present also some other characteristics that are instead supposed to be configurable on a per-platform base since they represent configuration features tied to the specific hardware/firmware system. The immutable fields are already qualified as const on the their own; get rid of the structure-level const qualifier which is not needed, so as to enable possible runtime customization of the mutable configuration features. No functional change. Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Tested-by: Peng Fan <peng.fan@nxp.com> #i.MX95 19x19 EVK Message-Id: <20240730144707.1647025-2-cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2024-08-16firmware: arm_scmi: Remove legacy transport-layer codeCristian Marussi
Since all SCMI transports have been made standalone drivers, remove all the core SCMI stack legacy support that was needed to run transports as built into the stack. Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Message-Id: <20240812173340.3912830-10-cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2024-08-16firmware: arm_scmi: Make VirtIO transport a standalone driverCristian Marussi
Make SCMI VirtIO transport a standalone driver that can be optionally loaded as a module. CC: Michael S. Tsirkin <mst@redhat.com> CC: Igor Skalkin <igor.skalkin@opensynergy.com> CC: Peter Hilber <peter.hilber@opensynergy.com> Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Message-Id: <20240812173340.3912830-9-cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2024-08-16firmware: arm_scmi: Make OPTEE transport a standalone driverCristian Marussi
Make SCMI OPTEE transport a standalone driver that can be optionally loaded as a module. CC: Etienne Carriere <etienne.carriere@foss.st.com> Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Message-Id: <20240812173340.3912830-8-cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2024-08-16firmware: arm_scmi: Make SMC transport a standalone driverCristian Marussi
Make SCMI SMC transport a standalone driver that can be optionally loaded as a module. CC: Peng Fan <peng.fan@nxp.com> CC: Nikunj Kela <quic_nkela@quicinc.com> Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Message-Id: <20240812173340.3912830-7-cristian.marussi@arm.com> [sudeep.holla: moved Clang Thumb2 build fix to the new makefile] Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2024-08-13firmware: arm_scmi: Make MBOX transport a standalone driverCristian Marussi
Make SCMI mailbox transport a standalone driver that can be optionally loaded as a module; while at it, create a dedicated subdirectory and submenu for SCMI Transports. Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Message-Id: <20240812173340.3912830-6-cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2024-08-13firmware: arm_scmi: Add support for standalone transport driversCristian Marussi
Extend the core SCMI stack with structures and methods to allow for transports to be split out as standalone drivers, while still supporting old style transports, defined as built into the SCMI core stack. No functional change. Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Tested-by: Peng Fan <peng.fan@nxp.com> #i.MX95 19x19 EVK Tested-by: Florian Fainelli <florian.fainelli@broadcom.com> Message-Id: <20240812173340.3912830-5-cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2024-08-13firmware: arm_scmi: Introduce packet handling helpersCristian Marussi
Introduce a pair of structures initialized to contain all the existing packet handling helpers, both for transports based on shared memory and messages. No functional change. Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Tested-by: Peng Fan <peng.fan@nxp.com> #i.MX95 19x19 EVK Tested-by: Florian Fainelli <florian.fainelli@broadcom.com> Message-Id: <20240812173340.3912830-4-cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2024-08-13firmware: arm_scmi: Introduce setup_shmem_iomapPeng Fan
To get the address of shmem could be generalized by introducing setup_shmem_iomap. Then the duplicated code in mailbox.c, optee.c and smc.c could be dropped. Signed-off-by: Peng Fan <peng.fan@nxp.com> [ Cristian: use OF __free and make use of the new helper also in smc.c ] Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Tested-by: Peng Fan <peng.fan@nxp.com> #i.MX95 19x19 EVK Tested-by: Florian Fainelli <florian.fainelli@broadcom.com> Message-Id: <20240812173340.3912830-3-cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2024-08-09firmware: arm_scmi: Track basic SCMI communication debug metricsLuke Parkin
Add the support for counting some of the SCMI communication debug metrics like how many were sent successfully or with some errors, responses received, notifications and delayed responses, transfer timeouts and errors from the firmware/platform. In many cases, the traces exists. But the traces are not always necessarily enabled and getting such cumulative SCMI communication debug metrics helps in understanding if there are any possible improvements that can be made on either side of SCMI communication. Signed-off-by: Luke Parkin <luke.parkin@arm.com> Reviewed-by: Cristian Marussi <cristian.marussi@arm.com> Tested-by: Cristian Marussi <cristian.marussi@arm.com> Message-Id: <20240805131013.587016-4-sudeep.holla@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2024-08-09firmware: arm_scmi: Add support for debug metrics at the interfaceLuke Parkin
Since SCMI involves interaction with the entity(software, firmware and/or hardware) providing services or features, it is quite useful to track certain metrics(for pure debugging purposes) like how many messages were sent or received, were there any failures, what kind of failures, ..etc. Add a new optional config option for the above purpose and the initial support for counting such key debug metrics. Signed-off-by: Luke Parkin <luke.parkin@arm.com> Reviewed-by: Cristian Marussi <cristian.marussi@arm.com> Tested-by: Cristian Marussi <cristian.marussi@arm.com> Message-Id: <20240805131013.587016-3-sudeep.holla@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2024-06-14firmware: arm_scmi: Add support for platform to agent channel completionPeng Fan
On some systems the SCMI platform to agent(p2a) communication can be fully interrupt driven. The notification(p2a) channel needs completion interrupt to drive its notification queue at the platform. Without it, the platform notification will not work as the platform will wait for agent indication of clearing the channel via interrupt unlike few platforms which can poll instead. To support such systems, an optional unidirectional mailbox channel for p2a reply communication. If the platform sets channel INTR flag set indicating that it expects the agent to trigger the interrupt to acknowledge the reciept of the notification or any p2a message, and the completion interrupt channel is provided, send a mailbox message to the platform after the p2a message is read and channel is freed to accept new notifications or p2a messages. Signed-off-by: Peng Fan <peng.fan@nxp.com> Link: https://lore.kernel.org/r/20240510-scmi-notify-v2-2-e994cf14ef86@nxp.com Reviewed-by: Cristian Marussi <cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2024-03-26firmware: arm_scmi: Add helper to trace bad messagesCristian Marussi
Upon reception of malformed and unexpected timed-out SCMI messages, it is not possible to trace those bad messages in their entirety, because usually we cannot even retrieve the payload, or it is just not reliable. Add a helper to trace at least the content of the header of the received message while associating a meaningful tag and error code. Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Link: https://lore.kernel.org/r/20240325204620.1437237-3-cristian.marussi@arm.com Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2024-02-20firmware: arm_scmi: Make scmi_bus_type constRicardo B. Marliere
Now that the driver core can properly handle constant struct bus_type, move the scmi_bus_type variable to be a constant structure as well, placing it into read-only memory which can not be modified at runtime. Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net> Reviewed-by: Cristian Marussi <cristian.marussi@arm.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/20240211-bus_cleanup-firmware2-v1-2-1851c92c7be7@marliere.net Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2024-01-22firmware: arm_scmi: Check mailbox/SMT channel for consistencyCristian Marussi
On reception of a completion interrupt the shared memory area is accessed to retrieve the message header at first and then, if the message sequence number identifies a transaction which is still pending, the related payload is fetched too. When an SCMI command times out the channel ownership remains with the platform until eventually a late reply is received and, as a consequence, any further transmission attempt remains pending, waiting for the channel to be relinquished by the platform. Once that late reply is received the channel ownership is given back to the agent and any pending request is then allowed to proceed and overwrite the SMT area of the just delivered late reply; then the wait for the reply to the new request starts. It has been observed that the spurious IRQ related to the late reply can be wrongly associated with the freshly enqueued request: when that happens the SCMI stack in-flight lookup procedure is fooled by the fact that the message header now present in the SMT area is related to the new pending transaction, even though the real reply has still to arrive. This race-condition on the A2P channel can be detected by looking at the channel status bits: a genuine reply from the platform will have set the channel free bit before triggering the completion IRQ. Add a consistency check to validate such condition in the A2P ISR. Reported-by: Xinglong Yang <xinglong.yang@cixtech.com> Closes: https://lore.kernel.org/all/PUZPR06MB54981E6FA00D82BFDBB864FBF08DA@PUZPR06MB5498.apcprd06.prod.outlook.com/ Fixes: 5c8a47a5a91d ("firmware: arm_scmi: Make scmi core independent of the transport type") Cc: stable@vger.kernel.org # 5.15+ Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Tested-by: Xinglong Yang <xinglong.yang@cixtech.com> Link: https://lore.kernel.org/r/20231220172112.763539-1-cristian.marussi@arm.com Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2023-01-20firmware: arm_scmi: Add per-channel raw injection supportCristian Marussi
On a system configured with multiple transport channels, expose a few additional debugfs per-channel entries to allow a user to explicitly select which transport channel to use for the SCMI message injection. Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Tested-by: Florian Fainelli <f.fainelli@gmail.com> Tested-by: Vincent Guittot <vincent.guittot@linaro.org> Link: https://lore.kernel.org/r/20230118121426.492864-18-cristian.marussi@arm.com Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2023-01-20firmware: arm_scmi: Add internal platform/channel identifiersCristian Marussi
Add a couple of unique identifiers to channel and platform instance descriptors in order to emit more descriptive message dump traces. Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Tested-by: Florian Fainelli <f.fainelli@gmail.com> Tested-by: Vincent Guittot <vincent.guittot@linaro.org> Link: https://lore.kernel.org/r/20230118121426.492864-8-cristian.marussi@arm.com Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2023-01-20firmware: arm_scmi: Move errors defs and code to common.hCristian Marussi
Move SCMI error codes definitions and helper to the common.h header together with the delayed response timeout define. No functional change. Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Tested-by: Florian Fainelli <f.fainelli@gmail.com> Tested-by: Vincent Guittot <vincent.guittot@linaro.org> Link: https://lore.kernel.org/r/20230118121426.492864-7-cristian.marussi@arm.com Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2023-01-20firmware: arm_scmi: Add xfer helpers to provide raw accessCristian Marussi
Add a few SCMI helpers useful to implement SCMI raw access support. Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Tested-by: Florian Fainelli <f.fainelli@gmail.com> Tested-by: Vincent Guittot <vincent.guittot@linaro.org> Link: https://lore.kernel.org/r/20230118121426.492864-6-cristian.marussi@arm.com Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2023-01-20firmware: arm_scmi: Refactor polling helpersCristian Marussi
Refactor polling helpers to receive scmi_desc directly as a parameter and move all of them to common.h. No functional change. Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Tested-by: Florian Fainelli <f.fainelli@gmail.com> Tested-by: Vincent Guittot <vincent.guittot@linaro.org> Link: https://lore.kernel.org/r/20230118121426.492864-3-cristian.marussi@arm.com Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2023-01-19firmware: arm_scmi: Split bus and driver into distinct modulesCristian Marussi
Make the SCMI bus on its own as a distinct module initialized at subsys_initcall level when builtin. Keep the SCMI driver core stack, together with any configured transport, in a different module initialized as module_init level. SCMI drivers initialization remain unchanged at module_init level. Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Link: https://lore.kernel.org/r/20221222185049.737625-10-cristian.marussi@arm.com Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2023-01-19firmware: arm_scmi: Refactor device create/destroy helpersCristian Marussi
Refactor SCMI device create/destroy helpers: it is now possible to ask for the creation of all the currently requested devices for a whole protocol, not only for the creation of a single well-defined device. While at that, re-instate uniqueness checks on the creation of SCMI SystemPower devices. Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Link: https://lore.kernel.org/r/20221222185049.737625-8-cristian.marussi@arm.com Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2023-01-19firmware: arm_scmi: Move handle get/set helpersCristian Marussi
Move handle get/set helpers definitions into driver.c and invoke them through the bus notifier helper. Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Link: https://lore.kernel.org/r/20221222185049.737625-7-cristian.marussi@arm.com Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2023-01-19firmware: arm_scmi: Refactor protocol device creationCristian Marussi
Move protocol device request helpers from driver.c compilation unit to bus.c, so reducing the cross interactions between driver.c and bus.c. Get rid of old protocol device creation process as a whole from driver.c and remove also stale SCMI system power unicity checks. While at that make such helpers call into scmi_requested_devices_nh notification chain. Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Link: https://lore.kernel.org/r/20221222185049.737625-6-cristian.marussi@arm.com Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2023-01-19firmware: arm_scmi: Add common notifier helpersCristian Marussi
Add a pair of notifier chains and generic empty notifier callbacks. Currently they are still unused but they will be used to act properly on device request and creation events. Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Link: https://lore.kernel.org/r/20221222185049.737625-5-cristian.marussi@arm.com Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2023-01-19firmware: arm_scmi: Move protocol registration helpersCristian Marussi
Move protocol registration helpers and logic out of bus.c compilation unit into driver.c. No functional change. Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Link: https://lore.kernel.org/r/20221222185049.737625-4-cristian.marussi@arm.com Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2023-01-19firmware: arm_scmi: Use dedicated devices to initialize channelsCristian Marussi
Refactor channels initialization to use dedicated transport devices instead of using devices borrowed from the SCMI drivers. Initialize all channels, as described in the device tree, upfront during SCMI core stack probe phase and free all of them, including the underlying devices, when the SCMI core is removed. Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Link: https://lore.kernel.org/r/20221222185049.737625-3-cristian.marussi@arm.com Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2023-01-19firmware: arm_scmi: Simplify chan_available transport operationCristian Marussi
SCMI transport operation .chan_available determines in a transport specific way if an SCMI channel is still available and to be configured. Such information is derived by analyzing bits of device node in a transport specific way, all it needs is a device node to operate up on, not necessarily a full blown device. Simplify the helper to receive in input a reference to a device_node instead of a device carrying a pointer to such device_node. Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Link: https://lore.kernel.org/r/20221222185049.737625-2-cristian.marussi@arm.com Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2022-11-01firmware: arm_scmi: Make tx_prepare time out eventuallyCristian Marussi
SCMI transports based on shared memory, at start of transmissions, have to wait for the shared Tx channel area to be eventually freed by the SCMI platform before accessing the channel. In fact the channel is owned by the SCMI platform until marked as free by the platform itself and, as such, cannot be used by the agent until relinquished. As a consequence a badly misbehaving SCMI platform firmware could lock the channel indefinitely and make the kernel side SCMI stack loop forever waiting for such channel to be freed, possibly hanging the whole boot sequence. Add a timeout to the existent Tx waiting spin-loop so that, when the system ends up in this situation, the SCMI stack can at least bail-out, nosily warn the user, and abort the transmission. Reported-by: YaxiongTian <iambestgod@outlook.com> Suggested-by: YaxiongTian <iambestgod@outlook.com> Cc: Vincent Guittot <vincent.guittot@linaro.org> Cc: Etienne Carriere <etienne.carriere@linaro.org> Cc: Florian Fainelli <f.fainelli@gmail.com> Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Link: https://lore.kernel.org/r/20221028140833.280091-3-cristian.marussi@arm.com Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2022-11-01firmware: arm_scmi: Cleanup the core driver removal callbackCristian Marussi
Platform drivers .remove callbacks are not supposed to fail and report errors. Such errors are indeed ignored by the core platform drivers and the driver unbind process is anyway completed. The SCMI core platform driver as it is now, instead, bails out reporting an error in case of an explicit unbind request. Fix the removal path by adding proper device links between the core SCMI device and the SCMI protocol devices so that a full SCMI stack unbind is triggered when the core driver is removed. The remove process does not bail out anymore on the anomalous conditions triggered by an explicit unbind but the user is still warned. Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Link: https://lore.kernel.org/r/20221028140833.280091-1-cristian.marussi@arm.com Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2022-04-28firmware: arm_scmi: Split protocol specific definitions in a dedicated headerCristian Marussi
Move some SCMI protocol specific definitions from common.h into a the new dedicated protocols.h header so that SCMI protocols core code can include only what it needs; this is going to be useful to avoid the risk of growing indefinitely the dimension of common.h, especially when introducing some common protocols helper functions. Header common.h will continue to be included by SCMI core and transport layers. Link: https://lore.kernel.org/r/20220330150551.2573938-10-cristian.marussi@arm.com Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2022-04-28firmware: arm_scmi: Dynamically allocate implemented protocols arrayCristian Marussi
Move away from a statically allocated array for holding the current set of protocols implemented by the platform in favour of allocating it dynamically based on the number of protocols effectively advertised by the platform via BASE protocol exchanges. While at that, rectify the BASE_DISCOVER_LIST_PROTOCOLS loop iterations to terminate only when a number of protocols equal to the advertised ones has been received, instead of looping till the platform returns no more protocols descriptors. This new behaviour is better compliant with the specification and it has been tested to work equally well against an SCMI stack running on top of an official SCP firmware on a JUNO board. Link: https://lore.kernel.org/r/20220330150551.2573938-6-cristian.marussi@arm.com Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-12-21firmware: arm_scmi: Add new parameter to mark_txdoneCristian Marussi
Add a new xfer parameter to mark_txdone transport operation which enables the SCMI core to optionally pass back into the transport layer a reference to the xfer descriptor that is being handled. Link: https://lore.kernel.org/r/20211220195646.44498-9-cristian.marussi@arm.com Reviewed-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>
2021-12-21firmware: arm_scmi: Add support for atomic transportsCristian Marussi
An SCMI transport can be configured as .atomic_enabled in order to signal to the SCMI core that all its TX path is executed in atomic context and that, when requested, polling mode should be used while waiting for command responses. When a specific platform configuration had properly configured such a transport as .atomic_enabled, the SCMI core will also take care not to sleep in the corresponding RX path while waiting for a response if that specific command transaction was requested as atomic using polling mode. Asynchronous commands should not be used in an atomic context and so a warning is emitted if polling was requested for an asynchronous command. Add also a method to check, from the SCMI drivers, if the underlying SCMI transport is currently configured to support atomic transactions: this will be used by upper layers to determine if atomic requests can be supported at all on this SCMI instance. Link: https://lore.kernel.org/r/20211220195646.44498-7-cristian.marussi@arm.com Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-12-21firmware: arm_scmi: Add sync_cmds_completed_on_ret transport flagCristian Marussi
Add a flag to let the transport signal to the core if its handling of sync command implies that, after .send_message has returned successfully, the requested command can be assumed to be fully and completely executed on SCMI platform side so that any possible response value is already immediately available to be retrieved by a .fetch_response: in other words the polling phase can be skipped in such a case and the response values accessed straight away. Note that all of the above applies only when polling mode of operation was selected by the core: if instead a completion IRQ was found to be available the normal response processing path based on completions will still be followed. Link: https://lore.kernel.org/r/20211220195646.44498-4-cristian.marussi@arm.com Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-12-21firmware: arm_scmi: Add configurable polling mode for transportsCristian Marussi
SCMI communications along TX channels can optionally be provided of a completion interrupt; when such interrupt is not available, command transactions should rely on polling, where the SCMI core takes care to repeatedly evaluate the transport-specific .poll_done() function, if available, to determine if and when a request was fully completed or timed out. Such mechanism is already present and working on a single transfer base: SCMI protocols can indeed enable hdr.poll_completion on specific commands ahead of each transfer and cause that transaction to be handled with polling. Introduce a couple of flags to be able to enforce such polling behaviour globally at will: - scmi_desc.force_polling: to statically switch the whole transport to polling mode. - scmi_chan_info.no_completion_irq: to switch a single channel dynamically to polling mode if, at runtime, is determined that no completion interrupt was available for such channel. Link: https://lore.kernel.org/r/20211220195646.44498-2-cristian.marussi@arm.com Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-11-17firmware: arm_scmi: Add optee transportEtienne Carriere
Add a new transport channel to the SCMI firmware interface driver for SCMI message exchange based on optee transport channel. The optee transport is realized by connecting and invoking OP-TEE SCMI service interface PTA. Optee transport support (CONFIG_ARM_SCMI_TRANSPORT_OPTEE) is default enabled when optee driver (CONFIG_OPTEE) is enabled. Effective optee transport is setup upon OP-TEE SCMI service discovery at optee device initialization. For this SCMI UUID is registered to the optee bus for probing. This is done from the link_supplier operator of the SCMI optee transport. The optee transport can use a statically defined shared memory in which case SCMI device tree node defines it using an "arm,scmi-shmem" compatible phandle through property shmem. Alternatively, optee transport allocates the shared memory buffer from the optee driver when no shmem property is defined. The protocol used to exchange SCMI message over that shared memory is negotiated between optee transport driver and the OP-TEE service through capabilities exchange. OP-TEE SCMI service is integrated in OP-TEE since its release tag 3.13.0. The service interface is published in [1]. Link: [1] https://github.com/OP-TEE/optee_os/blob/3.13.0/lib/libutee/include/pta_scmi_client.h Link: https://lore.kernel.org/r/20211028140009.23331-2-etienne.carriere@linaro.org Cc: Cristian Marussi <cristian.marussi@arm.com> Cc: Sudeep Holla <sudeep.holla@arm.com> Reviewed-by: Cristian Marussi <cristian.marussi@arm.com> Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-08-05firmware: arm_scmi: Add virtio transportIgor Skalkin
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>
2021-08-05firmware: arm_scmi: Add priv parameter to scmi_rx_callbackCristian Marussi
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>