xref: /freebsd/sys/dts/bindings-localbus.txt (revision a7623790fb345e6dc986dfd31df0ace115e6f2e4)
1$FreeBSD$
2
3Marvell Device bus (localbus) configuration.
4============================================
5
61. Properties for localbus nodes
7
81.1 ranges
9
10Property:	ranges
11
12Value type:	<prop-encoded-array> encoded as arbitrary number of localbus
13		nodes specifiers.
14
15Description:	ranges property defines values used for mapping devices
16		connected to localbus, in Marvell devices it is used also for
17		setting decoding windows.
18
19		a) child node address-cells:
20		   - first cell: number of bank (chip select)
21		   - second cell: (Marvell devices) Target ID for decoding
22		   	windows setup
23
24		b) parent node address cells:
25		   - address offset: used with parent's node base address to
26		   	specify base address of mapped device
27
28		c) child node size-cells:
29		   - size: defines amount of memory that should be reserved for
30			device
31
321.2 bank-count
33
34Property:	bank-count
35
36Value type:	<u32>
37
38Description:	The bank_count property defines maximum number of banks on
39		localbus node. Bank is most often interpreted as device chip
40		select, but may also describe another device (e.g. SPI flash).
41
421.3 Example
43
44	localbus@0 {
45		#address-cells = <2>;
46		#size-cells = <1>;
47		compatible = "mrvl,lbc";
48		bank-count = <5>;
49
50		/* This reflects CPU decode windows setup. */
51		ranges = <0x0 0x2f 0xb2200000 0x00100000
52			  0x1 0x3e 0xb2100000 0x00100000
53			  0x2 0x3d 0xb0000000 0x02000000
54			  0x3 0x3b 0xb2000000 0x00100000>;
55	};
56
572. Properties for localbus consumer nodes:
58
592.1 reg
60
61Property:	reg
62
63Value type: 	<prop-encoded-array>
64
65Description:	A standard property required for localbus child nodes. Defines
66		the device memory region.
67
68		a) first cell: number of bank (chip select)
69
70		b) address offset: used with address offset from parent's ranges
71			for corresponding bank to specify base address of
72			the device
73
74		c) size: defines size of the device memory region
75
762.2 Example
77
78	nor@0,0 {
79		#address-cells = <1>;
80		#size-cells = <1>;
81		compatible = "cfi-flash";
82		reg = <0x0 0x0 0x00100000>;
83	};
84