xref: /freebsd/sys/contrib/device-tree/Bindings/serial/nvidia,tegra194-tcu.txt (revision 02e9120893770924227138ba49df1edb3896112a)
1NVIDIA Tegra Combined UART (TCU)
2
3The TCU is a system for sharing a hardware UART instance among multiple
4systems within the Tegra SoC. It is implemented through a mailbox-
5based protocol where each "virtual UART" has a pair of mailboxes, one
6for transmitting and one for receiving, that is used to communicate
7with the hardware implementing the TCU.
8
9Required properties:
10- name : Should be tcu
11- compatible
12    Array of strings
13    One of:
14    - "nvidia,tegra194-tcu"
15- mbox-names:
16    "rx" - Mailbox for receiving data from hardware UART
17    "tx" - Mailbox for transmitting data to hardware UART
18- mboxes: Mailboxes corresponding to the mbox-names.
19
20This node is a mailbox consumer. See the following files for details of
21the mailbox subsystem, and the specifiers implemented by the relevant
22provider(s):
23
24- .../mailbox/mailbox.txt
25- .../mailbox/nvidia,tegra186-hsp.txt
26
27Example bindings:
28-----------------
29
30tcu: tcu {
31	compatible = "nvidia,tegra194-tcu";
32	mboxes = <&hsp_top0 TEGRA_HSP_MBOX_TYPE_SM 0>,
33	         <&hsp_aon TEGRA_HSP_MBOX_TYPE_SM 1>;
34	mbox-names = "rx", "tx";
35};
36