[RFC PATCH v4 00/14] coco/TSM: Host-side Arm CCA IDE setup via connect/disconnect callbacks

Aneesh Kumar K.V (Arm)
2026-04-27T06:51:35Z

This patch series implements the TSM ->connect() and ->disconnect() callbacks
required for the Arm CCA IDE setup as per the RMM 2.0bet1 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

Changes from v3:
https://lore.kernel.org/all/20260312080129.3483585-1-aneesh.kumar@kernel.org
* updated the patches to follow the RMM 2.0bet1 specification
* reworked the host-side pdev lifecycle to better match the RMM 2.0bet1 flow,
including common pdev state, root-port pdev support, and non-coherent stream
setup and teardown
* split PF0 setup into identity collection and conditional public-key
installation, and gate DA enablement on RMI_FEATURE_REGISTER_2_DA
* added coordinated handling for RMI_DEV_COMM_EXIT_STREAM_WAIT, along with
stream connect/disconnect and stream key refresh/purge support during vdev
teardown

Changes from v2:
rfc-v2 https://lore.kernel.org/all/20251027095602.1154418-1-aneesh.kumar@kernel.org
* rebase to latest kernel and core TSM changes
* Address review feedback.

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

[1] https://developer.arm.com/documentation/den0137/2-0bet1/
[2] https://lore.kernel.org/all/20260303000207.1836586-1-dan.j.williams@intel.com
[3] https://lore.kernel.org/all/20260318155413.793430-1-steven.price@arm.com
[4] https://gitlab.arm.com/linux-arm/linux-cca.git cca/topics/cca-tdisp-upstream-rfc-v4

Cc: Alexey Kardashevskiy <aik@amd.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jonathan Cameron <jic23@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Samuel Ortiz <sameo@rivosinc.com>
Cc: Steven Price <steven.price@arm.com>
Cc: Suzuki K Poulose <Suzuki.Poulose@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Xu Yilun <yilun.xu@linux.intel.com>

Aneesh Kumar K.V (Arm) (11):
coco: host: arm64: Add host TSM callback and IDE stream allocation
support
coco: host: arm64: Create RMM pdev objects for PCI endpoints
coco: host: arm64: Add RMM device communication helpers
coco: host: arm64: Add helper to stop and tear down an RMM pdev
coco: host: arm64: Register device public key with RMM
coco: host: arm64: Initialize RMM pdev state for TDISP IDE connect
coco: host: arm64: Coordinate peer stream waits during pdev
communication
coco: host: arm64: Connect RMM pdev streams for IDE devices
coco: host: arm64: Refcount root-port pdevs used by IDE streams
PCI/TSM: Move CMA DOE mailbox discovery out of
pci_tsm_pf0_constructor()
coco: host: arm64: Add NCOH_SYS stream support for RC endpoints

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/rmi_cmds.h | 85 +++
arch/arm64/include/asm/rmi_smc.h | 168 +++++
crypto/asymmetric_keys/x509_cert_parser.c | 9 +
crypto/asymmetric_keys/x509_loader.c | 38 +-
crypto/asymmetric_keys/x509_parser.h | 42 +-
drivers/crypto/ccp/sev-dev-tsm.c | 13 +
drivers/firmware/smccc/rmm.c | 12 +
drivers/firmware/smccc/rmm.h | 8 +
drivers/firmware/smccc/smccc.c | 1 +
drivers/pci/tsm/core.c | 14 +-
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 | 494 ++++++++++++
drivers/virt/coco/arm-cca-host/rmi-da.c | 867 ++++++++++++++++++++++
drivers/virt/coco/arm-cca-host/rmi-da.h | 217 ++++++
drivers/virt/coco/tdx-host/tdx-host.c | 13 +
include/keys/asymmetric-type.h | 2 +
include/keys/x509-parser.h | 57 ++
20 files changed, 2012 insertions(+), 59 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

--
2.43.0