Merge tag 'mfd-next-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/lee/mfd
[sfrench/cifs-2.6.git] / Documentation / devicetree / bindings / memory-controllers / atmel,ebi.txt
1 * Device tree bindings for Atmel EBI
2
3 The External Bus Interface (EBI) controller is a bus where you can connect
4 asynchronous (NAND, NOR, SRAM, ....) and synchronous memories (SDR/DDR SDRAMs).
5 The EBI provides a glue-less interface to asynchronous memories through the SMC
6 (Static Memory Controller).
7
8 Required properties:
9
10 - compatible:           "atmel,at91sam9260-ebi"
11                         "atmel,at91sam9261-ebi"
12                         "atmel,at91sam9263-ebi0"
13                         "atmel,at91sam9263-ebi1"
14                         "atmel,at91sam9rl-ebi"
15                         "atmel,at91sam9g45-ebi"
16                         "atmel,at91sam9x5-ebi"
17                         "atmel,sama5d3-ebi"
18                         "microchip,sam9x60-ebi"
19
20 - reg:                  Contains offset/length value for EBI memory mapping.
21                         This property might contain several entries if the EBI
22                         memory range is not contiguous
23
24 - #address-cells:       Must be 2.
25                         The first cell encodes the CS.
26                         The second cell encode the offset into the CS memory
27                         range.
28
29 - #size-cells:          Must be set to 1.
30
31 - ranges:               Encodes CS to memory region association.
32
33 - clocks:               Clock feeding the EBI controller.
34                         See clock-bindings.txt
35
36 Children device nodes are representing device connected to the EBI bus.
37
38 Required device node properties:
39
40 - reg:                  Contains the chip-select id, the offset and the length
41                         of the memory region requested by the device.
42
43 EBI bus configuration will be defined directly in the device subnode.
44
45 Optional EBI/SMC properties:
46
47 - atmel,smc-bus-width:          width of the asynchronous device's data bus
48                                 8, 16 or 32.
49                                 Default to 8 when undefined.
50
51 - atmel,smc-byte-access-type    "write" or "select" (see Atmel datasheet).
52                                 Default to "select" when undefined.
53
54 - atmel,smc-read-mode           "nrd" or "ncs".
55                                 Default to "ncs" when undefined.
56
57 - atmel,smc-write-mode          "nwe" or "ncs".
58                                 Default to "ncs" when undefined.
59
60 - atmel,smc-exnw-mode           "disabled", "frozen" or "ready".
61                                 Default to "disabled" when undefined.
62
63 - atmel,smc-page-mode           enable page mode if present. The provided value
64                                 defines the page size (supported values: 4, 8,
65                                 16 and 32).
66
67 - atmel,smc-tdf-mode:           "normal" or "optimized". When set to
68                                 "optimized" the data float time is optimized
69                                 depending on the next device being accessed
70                                 (next device setup time is subtracted to the
71                                 current device data float time).
72                                 Default to "normal" when undefined.
73
74 If at least one atmel,smc- property is defined the following SMC timing
75 properties become mandatory. In the other hand, if none of the atmel,smc-
76 properties are specified, we assume that the EBI bus configuration will be
77 handled by the sub-device driver, and none of those properties should be
78 defined.
79
80 All the timings are expressed in nanoseconds (see Atmel datasheet for a full
81 description).
82
83 - atmel,smc-ncs-rd-setup-ns
84 - atmel,smc-nrd-setup-ns
85 - atmel,smc-ncs-wr-setup-ns
86 - atmel,smc-nwe-setup-ns
87 - atmel,smc-ncs-rd-pulse-ns
88 - atmel,smc-nrd-pulse-ns
89 - atmel,smc-ncs-wr-pulse-ns
90 - atmel,smc-nwe-pulse-ns
91 - atmel,smc-nwe-cycle-ns
92 - atmel,smc-nrd-cycle-ns
93 - atmel,smc-tdf-ns
94
95 Example:
96
97         ebi: ebi@10000000 {
98                 compatible = "atmel,sama5d3-ebi";
99                 #address-cells = <2>;
100                 #size-cells = <1>;
101                 atmel,smc = <&hsmc>;
102                 atmel,matrix = <&matrix>;
103                 reg = <0x10000000 0x10000000
104                        0x40000000 0x30000000>;
105                 ranges = <0x0 0x0 0x10000000 0x10000000
106                           0x1 0x0 0x40000000 0x10000000
107                           0x2 0x0 0x50000000 0x10000000
108                           0x3 0x0 0x60000000 0x10000000>;
109                 clocks = <&mck>;
110
111                 pinctrl-names = "default";
112                 pinctrl-0 = <&pinctrl_ebi_addr>;
113
114                 nor: flash@0,0 {
115                         compatible = "cfi-flash";
116                         #address-cells = <1>;
117                         #size-cells = <1>;
118                         reg = <0x0 0x0 0x1000000>;
119                         bank-width = <2>;
120
121                         atmel,smc-read-mode = "nrd";
122                         atmel,smc-write-mode = "nwe";
123                         atmel,smc-bus-width = <16>;
124                         atmel,smc-ncs-rd-setup-ns = <0>;
125                         atmel,smc-ncs-wr-setup-ns = <0>;
126                         atmel,smc-nwe-setup-ns = <8>;
127                         atmel,smc-nrd-setup-ns = <16>;
128                         atmel,smc-ncs-rd-pulse-ns = <84>;
129                         atmel,smc-ncs-wr-pulse-ns = <84>;
130                         atmel,smc-nrd-pulse-ns = <76>;
131                         atmel,smc-nwe-pulse-ns = <76>;
132                         atmel,smc-nrd-cycle-ns = <107>;
133                         atmel,smc-nwe-cycle-ns = <84>;
134                         atmel,smc-tdf-ns = <16>;
135                 };
136         };
137