[RFC PATCH v3 00/10] coco/TSM: Host-side Arm CCA IDE setup via connect/disconnect callbacks

Aneesh Kumar K.V (Arm)
2026-03-12T08:01:52Z

This patch series implements the TSM ->connect() and ->disconnect() callbacks
required for the Arm CCA IDE setup as per the RMM ALP17 specification [1].

This patchset includes the host-side flow needed by connect/disconnect,
including:
- DA feature detection helpers
- host TSM callback wiring and IDE stream allocation support
- creation/registration of RMM pdev descriptors
- RMM pdev communication helpers
- pdev stop and teardown helpers for disconnect
- pdev instantiation from the connect path
- public key registration with RMM

To support public-key handling from the device certificate chain, the series
also includes the required X.509 parser updates.

The series builds upon the TSM framework patches posted at [2] and depends on
the KVM CCA patchset [3]. A git repository containing all the related changes is
available at [4].

Testing / Usage

To initiate the IDE setup:
echo tsm0 > /sys/bus/pci/devices/$DEVICE/tsm/connect

To disconnect:
echo tsm0 > /sys/bus/pci/devices/$DEVICE/tsm/disconnect

Previous posting:
rfc-v1 https://lore.kernel.org/all/20250728135216.48084-1-aneesh.kumar@kernel.org
rfc-v2 https://lore.kernel.org/all/20251027095602.1154418-1-aneesh.kumar@kernel.org

Changes from v2:
* rebase to latest kernel and core TSM changes
* Address review feedback.

[1] https://developer.arm.com/-/cdn-downloads/permalink/Architectures/Armv9/DEN0137_1.1-alp17.zip
[2] https://lore.kernel.org/all/20260303000207.1836586-1-dan.j.williams@intel.com
[3] https://lore.kernel.org/all/461fa23f-9add-40e5-a0d0-759030e7c70b@arm.com
[4] https://gitlab.arm.com/linux-arm/linux-cca.git cca/topics/cca-tdisp-upstream-rfc-v3

Aneesh Kumar K.V (Arm) (7):
KVM: arm64: RMI: Add and export kvm_has_da_feature helper
coco: host: arm64: Add host TSM callback and IDE stream allocation
support
coco: host: arm64: Build and register RMM pdev descriptors
coco: host: arm64: Add RMM device communication helpers
coco: host: arm64: Add helper to stop and tear down an RMM pdev
coco: host: arm64: Instantiate RMM pdev during device connect
coco: host: arm64: Register device public key with RMM

Lukas Wunner (3):
X.509: Make certificate parser public
X.509: Parse Subject Alternative Name in certificates
X.509: Move certificate length retrieval into new helper

arch/arm64/include/asm/kvm_rmi.h | 1 +
arch/arm64/include/asm/rmi_cmds.h | 78 +++
arch/arm64/include/asm/rmi_smc.h | 183 ++++++-
arch/arm64/kvm/rmi.c | 6 +
crypto/asymmetric_keys/x509_cert_parser.c | 9 +
crypto/asymmetric_keys/x509_loader.c | 38 +-
crypto/asymmetric_keys/x509_parser.h | 42 +-
drivers/firmware/smccc/rmm.c | 12 +
drivers/firmware/smccc/rmm.h | 8 +
drivers/firmware/smccc/smccc.c | 1 +
drivers/virt/coco/Kconfig | 2 +
drivers/virt/coco/Makefile | 1 +
drivers/virt/coco/arm-cca-host/Kconfig | 23 +
drivers/virt/coco/arm-cca-host/Makefile | 5 +
drivers/virt/coco/arm-cca-host/arm-cca.c | 274 ++++++++++
drivers/virt/coco/arm-cca-host/rmi-da.c | 639 ++++++++++++++++++++++
drivers/virt/coco/arm-cca-host/rmi-da.h | 122 +++++
include/keys/asymmetric-type.h | 2 +
include/keys/x509-parser.h | 57 ++
19 files changed, 1448 insertions(+), 55 deletions(-)
create mode 100644 drivers/virt/coco/arm-cca-host/Kconfig
create mode 100644 drivers/virt/coco/arm-cca-host/Makefile
create mode 100644 drivers/virt/coco/arm-cca-host/arm-cca.c
create mode 100644 drivers/virt/coco/arm-cca-host/rmi-da.c
create mode 100644 drivers/virt/coco/arm-cca-host/rmi-da.h
create mode 100644 include/keys/x509-parser.h

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2.43.0