xref: /freebsd/sys/contrib/device-tree/Bindings/mips/cavium/bootbus.txt (revision 5ca8e32633c4ffbbcd6762e5888b6a4ba0708c6c)
1* Boot Bus
2
3The Octeon Boot Bus is a configurable parallel bus with 8 chip
4selects.  Each chip select is independently configurable.
5
6Properties:
7- compatible: "cavium,octeon-3860-bootbus"
8
9  Compatibility with all cn3XXX, cn5XXX and cn6XXX SOCs.
10
11- reg: The base address of the Boot Bus' register bank.
12
13- #address-cells: Must be <2>.  The first cell is the chip select
14   within the bootbus.  The second cell is the offset from the chip select.
15
16- #size-cells: Must be <1>.
17
18- ranges: There must be one one triplet of (child-bus-address,
19  parent-bus-address, length) for each active chip select.  If the
20  length element for any triplet is zero, the chip select is disabled,
21  making it inactive.
22
23The configuration parameters for each chip select are stored in child
24nodes.
25
26Configuration Properties:
27- compatible:  "cavium,octeon-3860-bootbus-config"
28
29- cavium,cs-index: A single cell indicating the chip select that
30  corresponds to this configuration.
31
32- cavium,t-adr: A cell specifying the ADR timing (in nS).
33
34- cavium,t-ce: A cell specifying the CE timing (in nS).
35
36- cavium,t-oe: A cell specifying the OE timing (in nS).
37
38- cavium,t-we: A cell specifying the WE timing (in nS).
39
40- cavium,t-rd-hld: A cell specifying the RD_HLD timing (in nS).
41
42- cavium,t-wr-hld: A cell specifying the WR_HLD timing (in nS).
43
44- cavium,t-pause: A cell specifying the PAUSE timing (in nS).
45
46- cavium,t-wait: A cell specifying the WAIT timing (in nS).
47
48- cavium,t-page: A cell specifying the PAGE timing (in nS).
49
50- cavium,t-rd-dly: A cell specifying the RD_DLY timing (in nS).
51
52- cavium,pages: A cell specifying the PAGES parameter (0 = 8 bytes, 1
53  = 2 bytes, 2 = 4 bytes, 3 = 8 bytes).
54
55- cavium,wait-mode: Optional.  If present, wait mode (WAITM) is selected.
56
57- cavium,page-mode: Optional.  If present, page mode (PAGEM) is selected.
58
59- cavium,bus-width: A cell specifying the WIDTH parameter (in bits) of
60  the bus for this chip select.
61
62- cavium,ale-mode: Optional.  If present, ALE mode is selected.
63
64- cavium,sam-mode: Optional.  If present, SAM mode is selected.
65
66- cavium,or-mode: Optional.  If present, OR mode is selected.
67
68Example:
69	bootbus: bootbus@1180000000000 {
70		compatible = "cavium,octeon-3860-bootbus";
71		reg = <0x11800 0x00000000 0x0 0x200>;
72		/* The chip select number and offset */
73		#address-cells = <2>;
74		/* The size of the chip select region */
75		#size-cells = <1>;
76		ranges = <0 0  0x0 0x1f400000  0xc00000>,
77			 <1 0  0x10000 0x30000000  0>,
78			 <2 0  0x10000 0x40000000  0>,
79			 <3 0  0x10000 0x50000000  0>,
80			 <4 0  0x0 0x1d020000  0x10000>,
81			 <5 0  0x0 0x1d040000  0x10000>,
82			 <6 0  0x0 0x1d050000  0x10000>,
83			 <7 0  0x10000 0x90000000  0>;
84
85			cavium,cs-config@0 {
86			compatible = "cavium,octeon-3860-bootbus-config";
87			cavium,cs-index = <0>;
88			cavium,t-adr  = <20>;
89			cavium,t-ce   = <60>;
90			cavium,t-oe   = <60>;
91			cavium,t-we   = <45>;
92			cavium,t-rd-hld = <35>;
93			cavium,t-wr-hld = <45>;
94			cavium,t-pause  = <0>;
95			cavium,t-wait   = <0>;
96			cavium,t-page   = <35>;
97			cavium,t-rd-dly = <0>;
98
99			cavium,pages     = <0>;
100			cavium,bus-width = <8>;
101		};
102		.
103		.
104		.
105		cavium,cs-config@6 {
106			compatible = "cavium,octeon-3860-bootbus-config";
107			cavium,cs-index = <6>;
108			cavium,t-adr  = <5>;
109			cavium,t-ce   = <300>;
110			cavium,t-oe   = <270>;
111			cavium,t-we   = <150>;
112			cavium,t-rd-hld = <100>;
113			cavium,t-wr-hld = <70>;
114			cavium,t-pause  = <0>;
115			cavium,t-wait   = <0>;
116			cavium,t-page   = <320>;
117			cavium,t-rd-dly = <0>;
118
119			cavium,pages     = <0>;
120			cavium,wait-mode;
121			cavium,bus-width = <16>;
122		};
123		.
124		.
125		.
126	};
127