3.9. FF-A manifest binding to device tree

This document defines the nodes and properties used to define a partition, according to the FF-A specification.

3.9.1. Partition Properties

• compatible [mandatory]

  • value type: <string>

  • Must be the string “arm,ffa-manifest-X.Y” which specifies the major and minor versions of the device tree binding for the FFA manifest represented by this node. The minor number is incremented if the binding changes in a backwards compatible manner.

    • X is an integer representing the major version number of this document.

    • Y is an integer representing the minor version number of this document.

• ffa-version [mandatory]

  • value type: <u32>

  • Must be two 16 bits values (X, Y), concatenated as 31:16 -> X, 15:0 -> Y, where:

    • X is the major version of FF-A expected by the partition at the FFA instance it will execute.

    • Y is the minor version of FF-A expected by the partition at the FFA instance it will execute.

• uuid [mandatory]

  • value type: <prop-encoded-array>

  • An array consisting of 4 <u32> values, identifying the UUID of the service implemented by this partition. The UUID format is described in RFC 4122.

• id

  • value type: <u32>

  • Pre-allocated partition ID.

• auxiliary-id

  • value type: <u32>

  • Pre-allocated ID that could be used in memory management transactions.

• description

  • value type: <string>

  • Name of the partition e.g. for debugging purposes.

• execution-ctx-count [mandatory]

  • value type: <u32>

  • Number of vCPUs that a VM or SP wants to instantiate.

    • In the absence of virtualization, this is the number of execution contexts that a partition implements.

    • If value of this field = 1 and number of PEs > 1 then the partition is treated as UP & migrate capable.

    • If the value of this field > 1 then the partition is treated as a MP capable partition irrespective of the number of PEs.

• exception-level [mandatory]

  • value type: <u32>

  • The target exception level for the partition:

    • 0x0: EL1

    • 0x1: S_EL0

    • 0x2: S_EL1

• execution-state [mandatory]

  • value type: <u32>

  • The target execution state of the partition:

    • 0: AArch64

    • 1: AArch32

• load-address

  • value type: <u64>

  • Physical base address of the partition in memory. Absence of this field indicates that the partition is position independent and can be loaded at any address chosen at boot time.

• entrypoint-offset

  • value type: <u64>

  • Offset from the base of the partition’s binary image to the entry point of the partition. Absence of this field indicates that the entry point is at offset 0x0 from the base of the partition’s binary.

• xlat-granule [mandatory]

  • value type: <u32>

  • Translation granule used with the partition:

    • 0x0: 4k

    • 0x1: 16k

    • 0x2: 64k

• boot-order

  • value type: <u16>

  • A unique number amongst all partitions that specifies if this partition must be booted before others. The partition with the smaller number will be booted first.

• rx-tx-buffer

  • value type: “memory-regions” node

  • Specific “memory-regions” nodes that describe the RX/TX buffers expected by the partition. The “compatible” must be the string “arm,ffa-manifest-rx_tx-buffer”.

• messaging-method [mandatory]

  • value type: <u16>

  • Specifies which messaging methods are supported by the partition, set bit means the feature is supported, clear bit - not supported:

    • Bit[0]: partition can receive direct requests via FFA_MSG_SEND_DIRECT_REQ ABI if set

    • Bit[1]: partition can send direct requests via FFA_MSG_SEND_DIRECT_REQ ABI if set

    • Bit[2]: partition can send and receive indirect messages

    • Bit[9]: partition can receive direct requests via FFA_MSG_SEND_DIRECT_REQ2 ABI if set

    • Bit[10]: partition can send direct requests via FFA_MSG_SEND_DIRECT_REQ2 ABI if set

• managed-exit

  • value type: <empty>

  • Specifies if managed exit is supported.

  • This field is deprecated in favor of ns-interrupts-action field in the FF-A v1.1 EAC0 spec.

• managed-exit-virq

  • value type: <empty>

  • Indicates if the partition needs managed exit, if supported, to be signaled through vFIQ signal.

• ns-interrupts-action [mandatory]

  • value type: <u32>

  • Specifies the action that the SPMC must take in response to a Non-secure physical interrupt.

    • 0x0: Non-secure interrupt is queued

    • 0x1: Non-secure interrupt is signaled after a managed exit

    • 0x2: Non-secure interrupt is signaled

  • This field supersedes the managed-exit field in the FF-A v1.0 spec.

• other-s-interrupts-action

  • value type: <u32>

  • Specifies the action that the SPMC must take in response to a Other-Secure physical interrupt.

    • 0x0: Other-Secure interrupt is queued

    • 0x1: Other-Secure interrupt is signaled

• runtime-model

  • value type: <u32>

  • Indicates whether the SP execution can be preempted.

  • This field is deprecated in favor of other-s-interrupts-action and ns-interrupts-action fields in the FF-A v1.1 spec.

• has-primary-scheduler

  • value type: <empty>

  • Presence of this field indicates that the partition implements the primary scheduler. If so, run-time EL must be EL1.

• time-slice-mem

  • value type: <empty>

  • Presence of this field indicates that the partition doesn’t expect the partition manager to time slice long running memory management functions.

• gp-register-num

  • value type: <u32>

  • The field specifies the general purpose register number but not its width. The width is derived from the partition’s execution state, as specified in the partition properties. For example, if the number value is 1 then the general-purpose register used will be x1 in AArch64 state and w1 in AArch32 state. Presence of this field indicates that the partition expects the address of the FF-A boot information blob to be passed in the specified general purpose register.

• power-management-messages

  • value type: <u32>

  • Specifies which power management messages a partition subscribes to. A set bit means the partition should be informed of the power event, clear bit - should not be informed of event:

    • Bit[0]: CPU_OFF

    • Bit[1]: CPU_SUSPEND

    • Bit[2]: CPU_SUSPEND_RESUME

3.9.2. Memory Regions

• compatible [mandatory]

  • value type: <string>

  • Must be the string “arm,ffa-manifest-memory-regions”.

• description

  • value type: <string>

  • Name of the memory region e.g. for debugging purposes.

• pages-count [mandatory]

  • value type: <u32>

  • Count of pages of memory region as a multiple of the translation granule size

• attributes [mandatory]

  • value type: <u32>

  • Mapping modes: ORed to get required permission

    • 0x1: Read

    • 0x2: Write

    • 0x4: Execute

    • 0x8: Security state

• base-address

  • value type: <u64>

  • Base address of the region. The address must be aligned to the translation granule size. The address given may be a Physical Address (PA), Virtual Address (VA), or Intermediate Physical Address (IPA). Refer to the FF-A specification for more information on the restrictions around the address type. If the base address is omitted then the partition manager must map a memory region of the specified size into the partition’s translation regime and then communicate the region properties (including the base address chosen by the partition manager) to the partition.

• stream-ids

  • value type: <prop-encoded-array>

  • List of IDs belonging to a DMA capable peripheral device that has access to the memory region represented by current node.

  • Each ID must have been declared in exactly one device region node.

• smmu-id

  • value type: <u32>

  • Identifies the SMMU IP that enforces the access control for the DMA device that owns the above stream-ids.

• stream-ids-access-permissions

  • value type: <prop-encoded-array>

  • List of attributes representing the instruction and data access permissions used by the DMA device streams to access the memory region represented by current node.

3.9.3. Device Regions

• compatible [mandatory]

  • value type: <string>

  • Must be the string “arm,ffa-manifest-device-regions”.

• description

  • value type: <string>

  • Name of the device region e.g. for debugging purposes.

• pages-count [mandatory]

  • value type: <u32>

  • Count of pages of memory region as a multiple of the translation granule size

• attributes [mandatory]

  • value type: <u32>

  • Mapping modes: ORed to get required permission

    • 0x1: Read

    • 0x2: Write

    • 0x4: Execute

    • 0x8: Security state

• base-address [mandatory]

  • value type: <u64>

  • Base address of the region. The address must be aligned to the translation granule size. The address given may be a Physical Address (PA), Virtual Address (VA), or Intermediate Physical Address (IPA). Refer to the FF-A specification for more information on the restrictions around the address type.

• smmu-id

  • value type: <u32>

  • On systems with multiple System Memory Management Units (SMMUs) this identifier is used to inform the partition manager which SMMU the device is upstream of. If the field is omitted then it is assumed that the device is not upstream of any SMMU.

• stream-ids

  • value type: <prop-encoded-array>

  • List of IDs where an ID is a unique <u32> value amongst all devices assigned to the partition.

• interrupts [mandatory]

  • value type: <prop-encoded-array>

  • A list of (id, attributes) pair describing the device interrupts, where:

    • id: The <u32> interrupt IDs.

    • attributes: A <u32> value, containing attributes for each interrupt ID:

      Field	Bit(s)
      Priority	7:0
      Security state	8
      Config(Edge/Level)	9
      Type(SPI/PPI/SGI)	11:10

      Security state:

      • Secure: 1

      • Non-secure: 0

      Configuration:

      • Edge triggered: 0

      • Level triggered: 1

      Type:

      • SPI: 0b10

      • PPI: 0b01

      • SGI: 0b00

• interrupts-target

  • value type: <prop-encoded-array>

  • A list of (id, mpdir upper bits, mpidr lower bits) tuples describing which mpidr the interrupt is routed to, where:

    • id: The <u32> interrupt ID. Must be one of those specified in the

      “interrupts” field.

    • mpidr upper bits: The <u32> describing the upper bits of the 64 bits

      mpidr

    • mpidr lower bits: The <u32> describing the lower bits of the 64 bits

      mpidr

• exclusive-access

  • value type: <empty>

  • Presence of this field implies that this endpoint must be granted exclusive access and ownership of this device’s MMIO region.

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