Hi Stefano,
Our use-case imply using scmi-smc-multiagent to be able to split scmi
between the domains,
so we would like to apply all patch series in the release.
On 23/08/2025 03:34, Stefano Stabellini wrote:
> I think it should be feasible to commit at least patches 1-4 in time for
> the release
>
> On Tue, 22 Jul 2025, Oleksii Moisieiev wrote:
>> Inroducing V4 RFC patch series on top of the Xen version 4.20-rc2
>> which includes implementation of the SCI SCMI SMC multi-agent support.
>>
>> Patch 1 "xen/arm: add generic SCI subsystem"
>> - rebased and refactored
>> - introduced DEVICE_ARM_SCI DT device class and used for SCI drivers probing
>> instead of custom,
>> linker sections based implementation.
>> - added SCI API for Dom0 DT handling, instead of manipulating with ARM arch
>> dom0 code directly.
>> - RFC changes in XEN_DOMCTL_assign_device OP processing
>> - Introduce arch_handle_passthrough_prop call to handle arm specific
>> nodes
>>
>> Patch 2 "xen/arm: scmi-smc: update to be used under sci subsystem"
>> - update driver introduced by commit 3e322bef8bc0 ("xen/arm: firmware: Add
>> SCMI
>> over SMC calls
>> handling layer") be used under sci subsystem.
>> - no functional changes in general
>>
>> Patch 3 "xen/arm: scmi-smc: passthrough SCMI SMC to guest domain
>> This is new change which allows passthrough SCMI SMC, single agent interface
>> to
>> guest domain
>> cover use case "thin Dom0 with guest domain, which serves as Driver domain".
>> See patch commit message for full description.
>>
>> Patch 4 - docs: arm: add docs for SCMI over SMC calls forwarding
>> driver
>> - add documentation section for Simple Arm SCMI over SMC/HVC calls
>> forwarding driver.
>>
>> Patch 6 - xen/domctl: extend XEN_DOMCTL_assign_device to handle not
>> only iommu
>> - add chainged handling of assigned DT devices to support
>> access-controller functionality through SCI framework.
>> Change was done in two parts:
>> - update iommu_do_dt_domctl() to check for dt_device_is_protected()
>> and not fail if DT device is not protected by IOMMU
>> -add chained call to sci_do_domctl() to do_domctl()
>>
>> Patch 9 - xen/arm: scmi: introduce SCI SCMI SMC multi-agent driver
>> - added "scmi-secondary-agents" and "#scmi-secondary-agent-cells"
>> property to "xen,config" node in "chosen" to inform SCI SCMI
>> multi-agent driver about available agents and their
>> configuration. It defines <agent_id> to <smc-id,scmi_shm> map.
>> This option is Xen specific as Xen is the only one entry in the
>> system which need to know about SCMI multi-agent support and
>> configuration.
>> - each guest using SCMI should be configured with SCMI agent_id, so SCMI
>> FW can implement Agent-specific permission policy.
>> -- dom0: dom0_scmi_agent_id=<agent_id> in Xen command line option
>> -- toolstack: arm_sci = "type=scmi_smc_multiagent,agent_id=<agent_id>"
>> -- dom0less: "xen,sci_type", "xen,sci_agent_id" properties in
>> "xen,domain" nodes.
>> - factored out SCMI generic definitions (re-usable)
>> - factored out SCMI shmem code (re-usable)
>> - the SCMI passthrough configuration for guest domains is similar to any
>> other
>> HW passthrough cfg.
>>
>> Patch 10 - docs: arm: add SCI SCMI SMC multi-agent driver docs
>> - add SCI SCMI SMC multi-agent driver documentation.
>>
>> Add separate SCMI DT node for Xen management agent under "xen,config"
>> node under chosen.
>>
>> All Xen-specific configuration provided under "/chosen" node. This
>> approach allows to isolate modifications to Host DT only under
>> "/chosen" node.
>>
>> This approach provides the following device tree (DT)
>> parameters (placed under xen,config node):
>>
>> - "scmi-secondary-agents": A Xen-specific parameter under the
>> "/chosen" node, which describes the SCMI agent configuration for
>> the domains.
>> - the SCMI configuration for Xen (privileged agent) and the shared
>> memory configuration for all agents are provided under the "/chosen"
>> node and are used strictly by Xen for its initial configuration.
>> - the scmi_shm and SCMI configuration for Dom0 are placed in the
>> "/firmware/scmi" node so that they can be moved to Dom0 without
>> any changes.
>>
>> This configuration allows the use of Xen-specific nodes to provide
>> information strictly needed by Xen while using the default SCMI
>> configuration for Dom0 and other domains. As a result, no additional
>> bindings need to be introduced to the device tree.
>> This simplifies the Xen SCMI multi-agent configuration and utilizes
>> generic device tree bindings for the domains.
>>
>> NOTE: Haven't added RB tags for patch 1 and 2 because rebase and some
>> minor changes were done.
>>
>> Code can be found at:
>> https://github.com/oleksiimoisieiev/xen/tree/scmi_upstrv5
>>
>> [1] RFC v2:
>> http://patchwork.kernel.org/project/xen-devel/cover/cover.1644341635.git.oleksii_moisie...@epam.com/
>> [2] RFC v3:
>> https://patchwork.kernel.org/project/xen-devel/patch/20250311111618.1850927-1-grygorii_stras...@epam.com
>> SCMI spec:
>> https://developer.arm.com/documentation/den0056/e/?lang=en
>>
>> SCMI bindings:
>> https://web.git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/devicetree/bindings/firmware/arm,scmi.yaml
>> https://web.git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/devicetree/bindings/access-controllers/access-controllers.yaml
>>
>> Reference EL3 FW:
>> RPI5: https://github.com/xen-troops/arm-trusted-firmware/commits/rpi5_dev/
>> Renesas v4h:
>> https://github.com/GrygiriiS/arm-trusted-firmware/commits/rcar_gen4_v2.7_v4x-scmi_upd/
>>
>> base-commit: dbe60f244c (Update Xen to 4.21, 2025-02-21)
>>
>> Changes in v5:
>> - update Maintainers file. Set role as a Reviewer
>> - rebased on the latest master branch
>> - Introduce arch_handle_passthrough_prop call to handle arm specific nodes
>> - rename dom0_scmi_smc_passthrough to scmi_smc_passthrough
>> - rename dom0_scmi_smc_passthrough in documentation
>> - set error code to -ENXIO when iommu is disabled
>> - return -EINVAL if mediator without assign_dt_device was provided
>> - invert return code check for iommu_do_domctl in
>> XEN_DOMCTL_assign_device domctl processing to make cleaner code
>> - change -ENOTSUPP error code to -ENXIO in sci_do_domctl
>> - handle -ENXIO return comde of iommu_do_domctl
>> - leave !dt_device_is_protected check in iommu_do_dt_domctl to make
>> code work the same way it's done in "handle_device" call while
>> creating hwdom(dom0) and "handle_passthrough_prop" call for dom0less
>> creation
>> - drop return check from sci_assign_dt_device call as not needed
>> - do not return EINVAL when addign_dt_device is not set. That is
>> because this callback is optional and not implemented in single-agent driver
>> - move memcpy_toio/fromio to the generic place
>> - fix device-tree example format in booting.txt, added ";" after "}".
>> - update define in scmi-proto.h
>> - update define in scmi-shmem.h file
>> - scmi_assign_device - do not ignore -EOPNOTSUPP return
>> code of the do_smc_xfer
>> - remove overwriting agent_channel->agent_id after
>> SCMI_BASE_DISCOVER_AGENT call
>> - add multi-agent files to the MAINTAINERS
>> - add SCMI multi-agent description to the SUPPORT.md
>> - handle ARM_SMCCC_INVALID_PARAMETER return code and return -EINVAL
>> for smc call
>> - updated collect_agents function. Set agent_id parameter as optional
>> in scmi-secondary-agents device-tree property
>> - introduce "#scmi-secondary-agents-cells" parameter to set if
>> agent_id was provided
>> - reanme xen,scmi-secondary-agents property to scmi-secondary-agents
>> - move memcpu_toio/fromio for the generic place
>> - update Xen to get management channel from /chosen/xen,config node
>> - get hypervisor channnel from node instead of using hardcoded
>> - update handling scmi and shmem nodes for the domain
>> - Set multi-agent driver to support only Arm64
>> - rework multi-agent driver to leave Host Device-tree unmodified
>>
>> Changes in v4:
>> - fix SPDX-License
>> - rename DEVICE_ARM_SCI DT device class to FIRMWARE_DEVICE
>> - move XEN_DOMCTL_assign_device code in separate patch
>> - Add documentation for SCI SCMI drivers
>> - xl.cfg doc
>> - fix comments from Stefano Stabellini
>> - fix toolstack code as sugested by Anthony PERARD
>> - use MATCH_OPTION()
>> - move arm_sci struct and cfg params in "arch_arm"
>> - add SCMI passthrough for dom0less case
>> - toolstack comments from Anthony PERARD
>> - added dom0less support
>> - added doc for "xen,scmi-secondary-agents"
>>
>> Grygorii Strashko (5):
>> xen/arm: scmi-smc: update to be used under sci subsystem
>> xen/arm: scmi-smc: passthrough SCMI SMC to domain, single agent
>> docs: arm: add docs for SCMI over SMC calls forwarding driver
>> xen/domctl: extend XEN_DOMCTL_assign_device to handle not only iommu
>> docs: arm: add SCI SCMI SMC multi-agent driver docs
>>
>> Oleksii Moisieiev (5):
>> xen/arm: add generic SCI subsystem
>> drivers: iommu: change error code when iommu is disabled
>> xen: arm: smccc: add INVALID_PARAMETER error code
>> lib/arm: Add I/O memory copy helpers
>> xen/arm: scmi: introduce SCI SCMI SMC multi-agent driver
>>
>> MAINTAINERS | 10 +
>> SUPPORT.md | 11 +
>> .../arm/firmware/arm-scmi.rst | 516 +++++++++++
>> docs/hypervisor-guide/arm/index.rst | 9 +
>> docs/hypervisor-guide/index.rst | 1 +
>> docs/man/xl.cfg.5.pod.in | 47 +
>> docs/misc/arm/device-tree/booting.txt | 103 +++
>> docs/misc/xen-command-line.pandoc | 18 +
>> tools/include/libxl.h | 5 +
>> tools/libs/light/libxl_arm.c | 18 +
>> tools/libs/light/libxl_types.idl | 12 +
>> tools/xl/xl_parse.c | 48 ++
>> xen/arch/arm/device.c | 5 +
>> xen/arch/arm/dom0less-build.c | 51 ++
>> xen/arch/arm/domain.c | 12 +-
>> xen/arch/arm/domain_build.c | 11 +-
>> xen/arch/arm/firmware/Kconfig | 37 +-
>> xen/arch/arm/firmware/Makefile | 2 +
>> xen/arch/arm/firmware/sci.c | 189 +++++
>> xen/arch/arm/firmware/scmi-proto.h | 164 ++++
>> xen/arch/arm/firmware/scmi-shmem.c | 112 +++
>> xen/arch/arm/firmware/scmi-shmem.h | 45 +
>> xen/arch/arm/firmware/scmi-smc-multiagent.c | 803 ++++++++++++++++++
>> xen/arch/arm/firmware/scmi-smc.c | 191 ++++-
>> xen/arch/arm/include/asm/domain.h | 5 +
>> xen/arch/arm/include/asm/firmware/sci.h | 214 +++++
>> xen/arch/arm/include/asm/firmware/scmi-smc.h | 41 -
>> xen/arch/arm/include/asm/smccc.h | 1 +
>> xen/arch/arm/vsmc.c | 4 +-
>> xen/common/device-tree/dom0less-build.c | 4 +
>> xen/common/domctl.c | 19 +
>> xen/drivers/passthrough/device_tree.c | 6 +
>> xen/drivers/passthrough/iommu.c | 2 +-
>> xen/include/asm-generic/device.h | 1 +
>> xen/include/asm-generic/dom0less-build.h | 9 +
>> xen/include/public/arch-arm.h | 8 +
>> xen/include/xen/lib/arm/io.h | 15 +
>> xen/lib/Makefile | 1 +
>> xen/lib/arm/Makefile | 1 +
>> xen/lib/arm/io.c | 80 ++
>> 40 files changed, 2744 insertions(+), 87 deletions(-)
>> create mode 100644 docs/hypervisor-guide/arm/firmware/arm-scmi.rst
>> create mode 100644 docs/hypervisor-guide/arm/index.rst
>> create mode 100644 xen/arch/arm/firmware/sci.c
>> create mode 100644 xen/arch/arm/firmware/scmi-proto.h
>> create mode 100644 xen/arch/arm/firmware/scmi-shmem.c
>> create mode 100644 xen/arch/arm/firmware/scmi-shmem.h
>> create mode 100644 xen/arch/arm/firmware/scmi-smc-multiagent.c
>> create mode 100644 xen/arch/arm/include/asm/firmware/sci.h
>> delete mode 100644 xen/arch/arm/include/asm/firmware/scmi-smc.h
>> create mode 100644 xen/include/xen/lib/arm/io.h
>> create mode 100644 xen/lib/arm/Makefile
>> create mode 100644 xen/lib/arm/io.c
>>
>> --
>> 2.34.1
>>
