1ARM MHU Mailbox Driver
2======================
3
4The ARM's Message-Handling-Unit (MHU) is a mailbox controller that has
53 independent channels/links to communicate with remote processor(s).
6 MHU links are hardwired on a platform. A link raises interrupt for any
7received data. However, there is no specified way of knowing if the sent
8data has been read by the remote. This driver assumes the sender polls
9STAT register and the remote clears it after having read the data.
10The last channel is specified to be a 'Secure' resource, hence can't be
11used by Linux running NS.
12
13Mailbox Device Node:
14====================
15
16Required properties:
17--------------------
18- compatible:		Shall be "arm,mhu" & "arm,primecell"
19- reg:			Contains the mailbox register address range (base
20			address and length)
21- #mbox-cells		Shall be 1 - the index of the channel needed.
22- interrupts:		Contains the interrupt information corresponding to
23			each of the 3 links of MHU.
24
25Example:
26--------
27
28	mhu: mailbox@2b1f0000 {
29		#mbox-cells = <1>;
30		compatible = "arm,mhu", "arm,primecell";
31		reg = <0 0x2b1f0000 0x1000>;
32		interrupts = <0 36 4>, /* LP-NonSecure */
33			     <0 35 4>, /* HP-NonSecure */
34			     <0 37 4>; /* Secure */
35		clocks = <&clock 0 2 1>;
36		clock-names = "apb_pclk";
37	};
38
39	mhu_client: scb@2e000000 {
40		compatible = "fujitsu,mb86s70-scb-1.0";
41		reg = <0 0x2e000000 0x4000>;
42		mboxes = <&mhu 1>; /* HP-NonSecure */
43	};
44