xref: /freebsd/sys/contrib/device-tree/Bindings/memory-controllers/atmel,ebi.txt (revision 7fdf597e96a02165cfe22ff357b857d5fa15ed8a)
1* Device tree bindings for Atmel EBI
2
3The External Bus Interface (EBI) controller is a bus where you can connect
4asynchronous (NAND, NOR, SRAM, ....) and synchronous memories (SDR/DDR SDRAMs).
5The EBI provides a glue-less interface to asynchronous memories through the SMC
6(Static Memory Controller).
7
8Required 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
36Children device nodes are representing device connected to the EBI bus.
37
38Required 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
43EBI bus configuration will be defined directly in the device subnode.
44
45Optional 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
74If at least one atmel,smc- property is defined the following SMC timing
75properties become mandatory. In the other hand, if none of the atmel,smc-
76properties are specified, we assume that the EBI bus configuration will be
77handled by the sub-device driver, and none of those properties should be
78defined.
79
80All the timings are expressed in nanoseconds (see Atmel datasheet for a full
81description).
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
95Example:
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
138