54 lines
1.6 KiB
Plaintext
54 lines
1.6 KiB
Plaintext
|
Texas Instruments TI SCI Clock Controller
|
||
|
|
=========================================
|
||
|
|
|
||
|
|
All clocks on Texas Instruments' SoCs that contain a System Controller,
|
||
|
|
are only controlled by this entity. Communication between a host processor
|
||
|
|
running an OS and the System Controller happens through a protocol known
|
||
|
|
as TI SCI[1]. This clock implementation plugs into the common clock
|
||
|
|
framework and makes use of the TI SCI protocol on clock API requests.
|
||
|
|
|
||
|
|
[1] http://processors.wiki.ti.com/index.php/TISCI
|
||
|
|
|
||
|
|
Clock Controller Node
|
||
|
|
=====================
|
||
|
|
The clock controller node represents the clocks managed by the SYSFW. Because
|
||
|
|
this relies on the TI SCI protocol to communicate with the SYSFW it must be a
|
||
|
|
child of the sysfw node.
|
||
|
|
|
||
|
|
Required Properties:
|
||
|
|
--------------------
|
||
|
|
- compatible: Must be "ti,k2g-sci-clk"
|
||
|
|
- #clock-cells: Must be be 2. In clock consumers, this cell represents the
|
||
|
|
device ID and clock ID exposed by the SYSFW firmware.
|
||
|
|
|
||
|
|
Example (AM65x):
|
||
|
|
----------------
|
||
|
|
dmsc: dmsc {
|
||
|
|
compatible = "ti,k2g-sci";
|
||
|
|
...
|
||
|
|
k3_clks: clocks {
|
||
|
|
compatible = "ti,k2g-sci-clk";
|
||
|
|
#clock-cells = <2>;
|
||
|
|
};
|
||
|
|
};
|
||
|
|
|
||
|
|
Clock Consumers
|
||
|
|
===============
|
||
|
|
Hardware blocks supplied by a clock should contain a "clocks" property that is
|
||
|
|
a phandle pointing to the clock controller node along with an index representing
|
||
|
|
the device id together with a clock ID to be passed to the SYSFW for device
|
||
|
|
control.
|
||
|
|
|
||
|
|
Required Properties:
|
||
|
|
--------------------
|
||
|
|
- clocks: phandle pointing to the corresponding clock node, an ID representing
|
||
|
|
the device, and an index representing a clock.
|
||
|
|
|
||
|
|
Example (AM65x):
|
||
|
|
----------------
|
||
|
|
uart2: serial@02800000 {
|
||
|
|
compatible = "ti,omap4-uart";
|
||
|
|
...
|
||
|
|
clocks = <&k3_clks 0x0007 1>;
|
||
|
|
};
|