xref: /freebsd/sys/contrib/device-tree/Bindings/arm/keystone/ti,sci.txt (revision 7fdf597e96a02165cfe22ff357b857d5fa15ed8a)
1Texas Instruments System Control Interface (TI-SCI) Message Protocol
2--------------------------------------------------------------------
3
4Texas Instrument's processors including those belonging to Keystone generation
5of processors have separate hardware entity which is now responsible for the
6management of the System on Chip (SoC) system. These include various system
7level functions as well.
8
9An example of such an SoC is K2G, which contains the system control hardware
10block called Power Management Micro Controller (PMMC). This hardware block is
11initialized early into boot process and provides services to Operating Systems
12on multiple processors including ones running Linux.
13
14See http://processors.wiki.ti.com/index.php/TISCI for protocol definition.
15
16TI-SCI controller Device Node:
17=============================
18
19The TI-SCI node describes the Texas Instrument's System Controller entity node.
20This parent node may optionally have additional children nodes which describe
21specific functionality such as clocks, power domain, reset or additional
22functionality as may be required for the SoC. This hierarchy also describes the
23relationship between the TI-SCI parent node to the child node.
24
25Required properties:
26-------------------
27- compatible:	should be "ti,k2g-sci" for TI 66AK2G SoC
28		should be "ti,am654-sci" for for TI AM654 SoC
29- mbox-names:
30	"rx" - Mailbox corresponding to receive path
31	"tx" - Mailbox corresponding to transmit path
32
33- mboxes: Mailboxes corresponding to the mbox-names. Each value of the mboxes
34	  property should contain a phandle to the mailbox controller device
35	  node and an args specifier that will be the phandle to the intended
36	  sub-mailbox child node to be used for communication.
37
38See Documentation/devicetree/bindings/mailbox/mailbox.txt for more details
39about the generic mailbox controller and client driver bindings. Also see
40Documentation/devicetree/bindings/mailbox/ti,message-manager.txt for typical
41controller that is used to communicate with this System controllers.
42
43Optional Properties:
44-------------------
45- reg-names:
46	debug_messages - Map the Debug message region
47- reg:  register space corresponding to the debug_messages
48- ti,system-reboot-controller: If system reboot can be triggered by SoC reboot
49- ti,host-id: Integer value corresponding to the host ID assigned by Firmware
50	for identification of host processing entities such as virtual
51	machines
52
53Example (K2G):
54-------------
55	pmmc: pmmc {
56		compatible = "ti,k2g-sci";
57		ti,host-id = <2>;
58		mbox-names = "rx", "tx";
59		mboxes= <&msgmgr &msgmgr_proxy_pmmc_rx>,
60			<&msgmgr &msgmgr_proxy_pmmc_tx>;
61		reg-names = "debug_messages";
62		reg = <0x02921800 0x800>;
63	};
64
65
66TI-SCI Client Device Node:
67=========================
68
69Client nodes are maintained as children of the relevant TI-SCI device node.
70
71Example (K2G):
72-------------
73	pmmc: pmmc {
74		compatible = "ti,k2g-sci";
75		...
76
77		my_clk_node: clk_node {
78			...
79			...
80		};
81
82		my_pd_node: pd_node {
83			...
84			...
85		};
86	};
87