I3C FIFO Target¶

The PxI3CFifoTarget class emulates an I3C target with host-accessible RX and TX FIFOs. A controller writes data on the bus into the RX FIFO (delivered to Python as events); Python enqueues data into the TX FIFO for the controller to read on the bus.

The target also supports standard I3C CCC handling, Dynamic Address Assignment, IBI, and Hot-Join.

TX FIFO depth is fixed at 2 KB (minus 8 bytes for bookkeeping overhead = 2040 bytes) and is not configurable from Python. A single enqueue call may transfer up to the available TX FIFO capacity. When the TX fifo is drained from a bus read, a sent event reports the byte count drained from the TX fifo.

Received data is sent to python as receive events, where each receive event delivers up to 1 KB of data. If a transfer is > 1 KB, it will be split into multiple events.

Features¶

2 KB TX FIFO with host-side enqueue and packeted bus events.
CCC handling including address assignment, MRL/MWL, GETCAPS, GETSTATUS, GETMXDS, and group addresses.
IBI and Hot-Join support when enabled through CCCs.

Data flow¶

Controller WRITE  →  RX FIFO  →  fifo_target_recv events  →  Python
Python enqueue    →  TX FIFO  →  Controller READ
Controller READ   →  (drains TX FIFO)  →  fifo_target_sent events  →  Python

PxI3CFifoTarget ¶

PxI3CFifoTarget(
    exerciser: AqProtocolExerciser,
    *args,
    pid: int | None = None,
    bcr: int = 0,
    dcr: int = 0,
    config: I3CFifoTargetConfig | None = None,
    static_addr: int = 0,
    minimum_mrl: int | None = None,
    minimum_mwl: int | None = None,
    getcaps_std_value: bytes | None = None,
    getcaps_usr_value: list[tuple[int, bytes]] | None = None,
    getstatus_std_value: bytes | None = None,
    getstatus_usr_value: list[tuple[int, bytes]] | None = None,
    getmxds_std_value: bytes | None = None,
    getmxds_usr_value: list[tuple[int, bytes]] | None = None,
    supported_group_address_count: int = 3,
    **kwargs
)

Bases: PxAbstractTarget

I3C FIFO target.

Emulates an I3C target with host-accessible RX and TX FIFOs. Bytes written by a controller on the bus are delivered to Python as packeted fifo_target_recv events. Bytes enqueued from Python are presented on subsequent bus reads; completed bus reads are reported as fifo_target_sent events with the byte count drained in each transaction.

The target also supports standard I3C CCC handling, IBI, and Hot-Join like other I3C targets.

CLASS	DESCRIPTION
`IbiType`	IBI type enumeration.
`HotJoinType`	Hot-Join type enumeration.

METHOD	DESCRIPTION
`add_event_handler`	Add an event handler to the current device instance.
`remove_event_handler`	Remove an event handler.
`get_event_handlers`	Retreive handlers registerd on this device.
`on_event`	Add an event handler to the instance by decorator.
`set_config`	Set the config of the target.
`detach_from_bus`	Detach the device from the bus.
`perform_operation`	Send an operation.
`attach_to_bus`	Attach the target to a bus.
`enqueue`	Enqueue bytes into the host-side TX FIFO.
`ibi_request`	Initiate an IBI request from the current target.
`send_hotjoin`	Initiate a Hot-Join request from the current target.

ATTRIBUTE	DESCRIPTION
`available_events_map`	A reverse mapping of `field_name_by_number`, which uses field name as key. TYPE: `dict[str, str]`
`is_attached`	Check if the device is attached to a bus. TYPE: `bool`
`state`	Get the state of the device. TYPE: `Message \| None`
`name`	Get the name of the device. TYPE: `str`
`additional_data`	Get the opaque additional data blob associated with this device. TYPE: `bytes`
`config`	Get the config of the device. TYPE: `Message \| None`
`cts_op_name`	Get the name of CTS operation. Currently not available now. TYPE: `str \| None`
`static_address`	Static address of the I3C FIFO target. TYPE: `int`
`assigned_address`	Get the assigned address of the target. TYPE: `int`
`event_state`	Get the event state of the target. TYPE: `int`
`group_addresses`	Get the group addresses assigned to the target. TYPE: `list[int]`
`mrl`	Get the maximum read length of the target. TYPE: `int`
`mwl`	Get the maximum write length of the target. TYPE: `int`
`tx_capacity`	Get the capacity of the FIFO. TYPE: `int`
`tx_fill`	Number of bytes currently in the TX FIFO. TYPE: `int`
`total_read`	Total bytes read by the controller from the target since configuration. TYPE: `int`
`total_written`	Total bytes written by the controller to the target since configuration. TYPE: `int`

available_events_map ¶

available_events_map: dict[str, str]

A reverse mapping of field_name_by_number, which uses field name as key.

is_attached ¶

is_attached: bool

Check if the device is attached to a bus.

state ¶

state: Message | None

Get the state of the device.

name ¶

name: str

Get the name of the device.

additional_data ¶

additional_data: bytes

Get the opaque additional data blob associated with this device.

config ¶

config: Message | None

Get the config of the device.

cts_op_name ¶

cts_op_name: str | None

Get the name of CTS operation. Currently not available now.

static_address ¶

static_address: int

Static address of the I3C FIFO target.

assigned_address ¶

assigned_address: int

Get the assigned address of the target.

event_state ¶

event_state: int

Get the event state of the target.

group_addresses ¶

group_addresses: list[int]

Get the group addresses assigned to the target.

mrl ¶

mrl: int

Get the maximum read length of the target.

mwl ¶

mwl: int

Get the maximum write length of the target.

tx_capacity ¶

tx_capacity: int

Get the capacity of the FIFO.

tx_fill ¶

tx_fill: int

Number of bytes currently in the TX FIFO.

total_read ¶

total_read: int

Total bytes read by the controller from the target since configuration.

total_written ¶

total_written: int

Total bytes written by the controller to the target since configuration.

IbiType ¶

Bases: IntEnum

IBI type enumeration.

HotJoinType ¶

Bases: IntEnum

Hot-Join type enumeration.

add_event_handler ¶

add_event_handler(event: str, handler: Callable[[Any], Any]) -> None

Add an event handler to the current device instance.

remove_event_handler ¶

remove_event_handler(event: str) -> None

Remove an event handler.

get_event_handlers ¶

get_event_handlers() -> dict[str, Callable]

Retreive handlers registerd on this device.

on_event ¶

on_event(event_type: str) -> Callable[[Callable[..., Any]], Callable[..., Any]]

Add an event handler to the instance by decorator.

set_config ¶

set_config(config: Message) -> None

Set the config of the target.

detach_from_bus ¶

detach_from_bus() -> None

Detach the device from the bus.

The opposite of the attach_to_bus method.

perform_operation ¶

perform_operation(operation: PxDeviceOperation) -> PxDeviceOperation

Send an operation.

attach_to_bus ¶

attach_to_bus(bus: PxAbstractBus) -> None

Attach the target to a bus.

This method is used to make the device aware of the bus it is connected to. It is used to set the bus attribute of the device.

Note

This method will not automatically create an actual instance on the Protocol Exerciser until user call the attach_to_bus method.

PARAMETER	DESCRIPTION
`bus` ¶	The bus to attach the device to TYPE: `PxAbstractBus`

RAISES	DESCRIPTION
`ValueError`	If the device is already attached to a bus

enqueue ¶

enqueue(data: list[int] | bytes) -> None

Enqueue bytes into the host-side TX FIFO.

ibi_request ¶

ibi_request(
    ibi_type: IbiType = IMMEDIATE,
    mdb_value: bytes = b"",
    additional_data: bytes = b"",
    skip_bcr_check: bool = False,
) -> None

Initiate an IBI request from the current target.

send_hotjoin ¶

send_hotjoin(hotjoin_type: HotJoinType = IMMEDIATE) -> None

Initiate a Hot-Join request from the current target.