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.. dtcompatible:: riscv,machine-timer
.. _dtbinding_riscv_machine_timer:

riscv,machine-timer
###################

Vendor: :ref:`RISC-V Foundation <dt_vendor_riscv>`

Description
***********



.. code-block:: none

   RISC-V Machine timer

Properties
**********

.. tabs::

   .. group-tab:: Node specific properties

      Properties not inherited from the base binding file.

      .. list-table::
         :widths: 1 1 4
         :header-rows: 1

         * - Name
           - Type
           - Details

         * - ``clk-divider``
           - ``int``
           - .. code-block:: none

                clk-divider specifies the division ratio to the CPU frequency that
                clock used by machine timer.
                This property supports the case that the machine timer and CPU use
                different clock sources.
                This configuration is used sometimes for such as low power consumption.

                For example, the CPU clock frequency is 108MHz, and the machine timer
                uses 27MHz, which is the CPU clock divided by 4.
                In this case, the CPU clock frequency is defined in the CPU node
                as follows

                   clock-frequency = <108000000>;

                This property takes exponent of the power of 2.
                The relationship with the frequency division ratio is as
                following equation.

                   division_ratio = 2^n
                   n = log_2(division_ratio)

                Setting clk-divider to 2 specifies the machine timer uses the clock
                that CPU clock frequency divided by (2^2=)4, or 27MHz.

                Devision ratio constants can be found in the
                dt-bindings/timer/nuclei-machine-timer.h header file.





   .. group-tab:: Deprecated node specific properties

      Deprecated properties not inherited from the base binding file.

      (None)

   .. group-tab:: Base properties

      Properties inherited from the base binding file, which defines
      common properties that may be set on many nodes. Not all of these
      may apply to the "riscv,machine-timer" compatible.

      .. list-table::
         :widths: 1 1 4
         :header-rows: 1

         * - Name
           - Type
           - Details

         * - ``status``
           - ``string``
           - .. code-block:: none

                indicates the operational status of a device


             Legal values: ``'ok'``, ``'okay'``, ``'disabled'``, ``'reserved'``, ``'fail'``, ``'fail-sss'``

             See :ref:`zephyr:dt-important-props` for more information.

         * - ``compatible``
           - ``string-array``
           - .. code-block:: none

                compatible strings


             This property is **required**.

             See :ref:`zephyr:dt-important-props` for more information.

         * - ``reg``
           - ``array``
           - .. code-block:: none

                register space


             See :ref:`zephyr:dt-important-props` for more information.

         * - ``reg-names``
           - ``string-array``
           - .. code-block:: none

                name of each register space


         * - ``interrupts``
           - ``array``
           - .. code-block:: none

                interrupts for device


             See :ref:`zephyr:dt-important-props` for more information.

         * - ``interrupts-extended``
           - ``compound``
           - .. code-block:: none

                extended interrupt specifier for device


         * - ``interrupt-names``
           - ``string-array``
           - .. code-block:: none

                name of each interrupt


         * - ``interrupt-parent``
           - ``phandle``
           - .. code-block:: none

                phandle to interrupt controller node


         * - ``label``
           - ``string``
           - .. code-block:: none

                Human readable string describing the device (used as device_get_binding() argument)


             See :ref:`zephyr:dt-important-props` for more information.

         * - ``clocks``
           - ``phandle-array``
           - .. code-block:: none

                Clock gate information


         * - ``clock-names``
           - ``string-array``
           - .. code-block:: none

                name of each clock


         * - ``#address-cells``
           - ``int``
           - .. code-block:: none

                number of address cells in reg property


         * - ``#size-cells``
           - ``int``
           - .. code-block:: none

                number of size cells in reg property


         * - ``dmas``
           - ``phandle-array``
           - .. code-block:: none

                DMA channels specifiers


         * - ``dma-names``
           - ``string-array``
           - .. code-block:: none

                Provided names of DMA channel specifiers


         * - ``io-channels``
           - ``phandle-array``
           - .. code-block:: none

                IO channels specifiers


         * - ``io-channel-names``
           - ``string-array``
           - .. code-block:: none

                Provided names of IO channel specifiers


         * - ``mboxes``
           - ``phandle-array``
           - .. code-block:: none

                mailbox / IPM channels specifiers


         * - ``mbox-names``
           - ``string-array``
           - .. code-block:: none

                Provided names of mailbox / IPM channel specifiers


         * - ``wakeup-source``
           - ``boolean``
           - .. code-block:: none

                Property to identify that a device can be used as wake up source.

                When this property is provided a specific flag is set into the
                device that tells the system that the device is capable of
                wake up the system.

                Wake up capable devices are disabled (interruptions will not wake up
                the system) by default but they can be enabled at runtime if necessary.



         * - ``power-domain``
           - ``phandle``
           - .. code-block:: none


                Power domain the device belongs to.

                The device will be notified when the power domain it belongs to is either
                suspended or resumed.