1Hisilicon Hi6220 Mailbox Driver
2===============================
3
4Hisilicon Hi6220 mailbox supports up to 32 channels. Each channel
5is unidirectional with a maximum message size of 8 words. I/O is
6performed using register access (there is no DMA) and the cell
7raises an interrupt when messages are received.
8
9Mailbox Device Node:
10====================
11
12Required properties:
13--------------------
14- compatible:		Shall be "hisilicon,hi6220-mbox"
15- reg:			Contains the mailbox register address range (base
16			address and length); the first item is for IPC
17			registers, the second item is shared buffer for
18			slots.
19- #mbox-cells:		Common mailbox binding property to identify the number
20			of cells required for the mailbox specifier. Must be 3.
21			<&phandle slot_id dst_irq ack_irq>
22			  phandle: Label name of mailbox controller
23			  slot_id: Slot id used either for TX or RX
24			  dst_irq: IRQ identifier index number which used by MCU
25			  ack_irq: IRQ identifier index number with generating a
26			           TX/RX interrupt to application processor,
27				   mailbox driver uses it to acknowledge interrupt
28- interrupts:		Contains the interrupt information for the mailbox
29			device. The format is dependent on which interrupt
30			controller the SoCs use.
31
32Optional Properties:
33--------------------
34- hi6220,mbox-tx-noirq: Property of MCU firmware's feature, so mailbox driver
35			use this flag to ask MCU to enable "automatic idle
36			flag" mode or IRQ generated mode to acknowledge a TX
37			completion.
38
39Example:
40--------
41
42	mailbox: mailbox@f7510000 {
43		compatible = "hisilicon,hi6220-mbox";
44		reg = <0x0 0xf7510000 0x0 0x1000>, /* IPC_S */
45		      <0x0 0x06dff800 0x0 0x0800>; /* Mailbox */
46		interrupt-parent = <&gic>;
47		interrupts = <GIC_SPI 94 IRQ_TYPE_LEVEL_HIGH>;
48		#mbox-cells = <3>;
49	};
50
51
52Mailbox client
53===============
54
55Required properties:
56--------------------
57- compatible:		Many (See the client docs).
58- mboxes:		Standard property to specify a Mailbox (See ./mailbox.txt)
59			Cells must match 'mbox-cells' (See Mailbox Device Node above).
60
61Optional Properties:
62--------------------
63- mbox-names:		Name given to channels seen in the 'mboxes' property.
64
65Example:
66--------
67
68	stub_clock: stub_clock {
69		compatible = "hisilicon,hi6220-stub-clk";
70		hisilicon,hi6220-clk-sram = <&sram>;
71		#clock-cells = <1>;
72		mbox-names = "mbox-tx", "mbox-rx";
73		mboxes = <&mailbox 1 0 11>, <&mailbox 0 1 10>;
74	};
75