summaryrefslogtreecommitdiff
path: root/drivers/firmware/arm_scmi/virtio.c
AgeCommit message (Collapse)Author
2022-02-21firmware: arm_scmi: Add atomic mode support to virtio transportCristian Marussi
Add support for .mark_txdone and .poll_done transport operations to SCMI VirtIO transport as pre-requisites to enable atomic operations. Add a Kernel configuration option to enable SCMI VirtIO transport polling and atomic mode for selected SCMI transactions while leaving it default disabled. Link: https://lore.kernel.org/r/20220217131234.50328-4-cristian.marussi@arm.com Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Igor Skalkin <igor.skalkin@opensynergy.com> Cc: Peter Hilber <peter.hilber@opensynergy.com> Cc: virtualization@lists.linux-foundation.org Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2022-02-21firmware: arm_scmi: Review virtio free_list handlingCristian Marussi
Add a new spinlock dedicated to the access of the TX free list and a couple of helpers to get and put messages back and forth from the free_list. Link: https://lore.kernel.org/r/20220217131234.50328-3-cristian.marussi@arm.com Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Igor Skalkin <igor.skalkin@opensynergy.com> Cc: Peter Hilber <peter.hilber@opensynergy.com> Cc: virtualization@lists.linux-foundation.org Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2022-02-21firmware: arm_scmi: Add a virtio channel refcountCristian Marussi
Currently SCMI VirtIO channels are marked with a ready flag and related lock to track channel lifetime and support proper synchronization at shutdown when virtqueues have to be stopped. This leads to some extended spinlocked sections with IRQs off on the RX path to keep hold of the ready flag and does not scale well especially when SCMI VirtIO polling mode will be introduced. Add an SCMI VirtIO channel dedicated refcount to track active users on both the TX and the RX path and properly enforce synchronization and cleanup at shutdown, inhibiting further usage of the channel once freed. Link: https://lore.kernel.org/r/20220217131234.50328-2-cristian.marussi@arm.com Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Igor Skalkin <igor.skalkin@opensynergy.com> Cc: Peter Hilber <peter.hilber@opensynergy.com> Cc: virtualization@lists.linux-foundation.org Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2022-02-07Merge tag 'scmi-updates-5.17' of ↵Sudeep Holla
git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux into for-next/scmi Arm SCMI firmware interface updates for v5.17 Couple of main additions: - Support for OPTEE based SCMI transport to enable using SCMI service provided by OPTEE on some platforms - Support for atomic SCMI transports which enables few SCMI transactions to be completed in atomic context. This involves other refactoring work associated with it. It also marks SMC and OPTEE as atomic transport as the commands are completed once the return Other changes involves some trace and log enhancements and a miscellaneous bug fix. * tag 'scmi-updates-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/sudeep.holla/linux: firmware: arm_scmi: Add new parameter to mark_txdone firmware: arm_scmi: Add atomic mode support to smc transport firmware: arm_scmi: Add support for atomic transports firmware: arm_scmi: Make optee support sync_cmds_completed_on_ret firmware: arm_scmi: Make smc support sync_cmds_completed_on_ret firmware: arm_scmi: Add sync_cmds_completed_on_ret transport flag firmware: arm_scmi: Make smc transport use common completions firmware: arm_scmi: Add configurable polling mode for transports firmware: arm_scmi: Use new trace event scmi_xfer_response_wait include: trace: Add new scmi_xfer_response_wait event firmware: arm_scmi: Refactor message response path firmware: arm_scmi: Set polling timeout to max_rx_timeout_ms firmware: arm_scmi: Perform earlier cinfo lookup call in do_xfer firmware: arm_scmi: optee: Drop the support for the OPTEE shared dynamic buffer firmware: arm_scmi: optee: Fix missing mutex_init() firmware: arm_scmi: Make virtio Version_1 compliance optional firmware: arm_scmi: Add optee transport dt-bindings: arm: Add OP-TEE transport for SCMI firmware: arm_scmi: Review some virtio log messages
2022-01-14virtio: wrap config->reset callsMichael S. Tsirkin
This will enable cleanups down the road. The idea is to disable cbs, then add "flush_queued_cbs" callback as a parameter, this way drivers can flush any work queued after callbacks have been disabled. Signed-off-by: Michael S. Tsirkin <mst@redhat.com> Link: https://lore.kernel.org/r/20211013105226.20225-1-mst@redhat.com Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
2021-11-17firmware: arm_scmi: Make virtio Version_1 compliance optionalCristian Marussi
Introduce a compilation option to disable strict enforcement of compliance against VirtIO Version_1 backends, so as to allow to support also Legacy VirtIO devices implementations. Link: https://lore.kernel.org/r/20211115102910.7639-1-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: Review some virtio log messagesCristian Marussi
Be more verbose avoiding to use _once flavour of dev_info/_err/_notice. Remove usage of __func_ to identify which vqueue is referred in some error messages and explicitly name the TX/RX vqueue. Link: https://lore.kernel.org/r/20210916103336.7243-1-cristian.marussi@arm.com Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-11-15firmware: arm_scmi: Fix null de-reference on error pathCristian Marussi
During channel setup a failure in the call of scmi_vio_feed_vq_rx() leads to an attempt to access a dev pointer by dereferencing vioch->cinfo at a time when vioch->cinfo has still to be initialized. Fix it by providing the device reference directly to scmi_vio_feed_vq_rx. Link: https://lore.kernel.org/r/20211112180705.41601-1-cristian.marussi@arm.com Fixes: 46abe13b5e3db ("firmware: arm_scmi: Add virtio transport") Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-10-06firmware: arm_scmi: Add proper barriers to scmi virtio deviceCristian Marussi
Only one single SCMI Virtio device is currently supported by this driver and it is referenced using a static global variable which is initialized once for all during probing and nullified at virtio device removal. Add proper SMP barriers to protect accesses to such device reference to ensure that the initialzation state of such device is correctly observed by all PEs at any time. Return -EBUSY, instead of -EINVAL, and a descriptive error message if more than one SCMI Virtio device is ever found and probed. Link: https://lore.kernel.org/r/20210916103336.7243-3-cristian.marussi@arm.com Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-10-06firmware: arm_scmi: Simplify spinlocks in virtio transportCristian Marussi
Remove unneeded nested irqsave/irqrestore spinlocks. Add also a few descriptive comments to explain better the system behaviour at shutdown time. Link: https://lore.kernel.org/r/20210916103336.7243-2-cristian.marussi@arm.com Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Sudeep Holla <sudeep.holla@arm.com> Signed-off-by: Cristian Marussi <cristian.marussi@arm.com> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-09-20firmware: arm_scmi: Remove __exit annotationArnd Bergmann
virtio_scmi_exit() is only called from __exit function, so the annotation is correct, but when the driver is built-in, the section gets discarded and the reference from a callback pointer causes a link-time error: `virtio_scmi_exit' referenced in section `.rodata' of drivers/firmware/arm_scmi/virtio.o: defined in discarded section `.exit.text' of drivers/firmware/arm_scmi/virtio.o I could not figure out a better workaround, so let's just remove that annotation even if it wastes a couple of bytes in .text. Link: https://lore.kernel.org/r/20210920100301.1466486-2-arnd@kernel.org Fixes: 46abe13b5e3d ("firmware: arm_scmi: Add virtio transport") Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
2021-08-09firmware: arm_scmi: Fix boolconv.cocci warningskernel test robot
drivers/firmware/arm_scmi/virtio.c:225:40-45: WARNING: conversion to bool not needed here Remove unneeded conversion to bool Semantic patch information: Relational and logical operators evaluate to bool, explicit conversion is overly verbose and unneeded. Generated by: scripts/coccinelle/misc/boolconv.cocci Link: https://lore.kernel.org/r/20210807173127.GA43248@a24dbc127934 CC: Igor Skalkin <igor.skalkin@opensynergy.com> Reported-by: kernel test robot <lkp@intel.com> Signed-off-by: kernel test robot <lkp@intel.com> 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>