dau_driver.linux_xdma
=====================

.. py:module:: dau_driver.linux_xdma


Attributes
----------

.. autoapisummary::

   dau_driver.linux_xdma.DEFAULT_DEV_ROOT
   dau_driver.linux_xdma.DEFAULT_SYSFS_PCI_ROOT
   dau_driver.linux_xdma.DEFAULT_BACKEND
   dau_driver.linux_xdma.DEFAULT_DMA_CONSTRAINTS
   dau_driver.linux_xdma._MAGIC_PROBE_ATTEMPTS
   dau_driver.linux_xdma._MAGIC_PROBE_DELAY_S


Functions
---------

.. autoapisummary::

   dau_driver.linux_xdma.discover_devices
   dau_driver.linux_xdma.identify_device
   dau_driver.linux_xdma._find_register_window
   dau_driver.linux_xdma._read_register
   dau_driver.linux_xdma._read_register_block_snapshot
   dau_driver.linux_xdma.endpoint_for_devnode
   dau_driver.linux_xdma._channel_paths
   dau_driver.linux_xdma._device_name


Module Contents
---------------

.. py:data:: DEFAULT_DEV_ROOT

.. py:data:: DEFAULT_SYSFS_PCI_ROOT

.. py:data:: DEFAULT_BACKEND
   :value: 'linux-xdma'


.. py:data:: DEFAULT_DMA_CONSTRAINTS

.. py:function:: discover_devices(root: str | pathlib.Path = DEFAULT_DEV_ROOT) -> list[dau_driver.device.DauDevice]

.. py:function:: identify_device(user_path: str | pathlib.Path, *, h2c_path: str | pathlib.Path | None = None, c2h_path: str | pathlib.Path | None = None) -> dau_driver.device.DauDevice

.. py:data:: _MAGIC_PROBE_ATTEMPTS
   :value: 5


.. py:data:: _MAGIC_PROBE_DELAY_S
   :value: 0.01


.. py:function:: _find_register_window(user_path: pathlib.Path) -> tuple[int, int]

.. py:function:: _read_register(user_path: pathlib.Path, register_window_offset: int, offset: dau_core.registers.RegisterOffset) -> int

.. py:function:: _read_register_block_snapshot(user_path: pathlib.Path, register_window_offset: int) -> dau_core.registers.RegisterBlockSnapshot

.. py:function:: endpoint_for_devnode(user_path: pathlib.Path, *, sysfs_root: pathlib.Path | None = None) -> str | None

   The PCI endpoint (``0000:04:00.0``) whose xdma instance owns this
   ``_user`` devnode, or None when sysfs does not say.

   The inverse of ``verify_advertisement.device_name_for_endpoint``, over
   the same layout: the devnodes hang off the PCI device in sysfs as
   ``<bdf>/xdma/<node>``. None rather than a raise on a missing sysfs, an
   unowned node or (never seen, but not guessed at) two owners, so the
   caller can fall back to a weaker name and say so.


.. py:function:: _channel_paths(user_path: pathlib.Path) -> tuple[pathlib.Path, pathlib.Path]

.. py:function:: _device_name(user_path: pathlib.Path) -> str