| * Device tree bindings for Atmel EBI |
| |
| The External Bus Interface (EBI) controller is a bus where you can connect |
| asynchronous (NAND, NOR, SRAM, ....) and synchronous memories (SDR/DDR SDRAMs). |
| The EBI provides a glue-less interface to asynchronous memories through the SMC |
| (Static Memory Controller). |
| |
| Required properties: |
| |
| - compatible: "atmel,at91sam9260-ebi" |
| "atmel,at91sam9261-ebi" |
| "atmel,at91sam9263-ebi0" |
| "atmel,at91sam9263-ebi1" |
| "atmel,at91sam9rl-ebi" |
| "atmel,at91sam9g45-ebi" |
| "atmel,at91sam9x5-ebi" |
| "atmel,sama5d3-ebi" |
| "microchip,sam9x60-ebi" |
| |
| - reg: Contains offset/length value for EBI memory mapping. |
| This property might contain several entries if the EBI |
| memory range is not contiguous |
| |
| - #address-cells: Must be 2. |
| The first cell encodes the CS. |
| The second cell encode the offset into the CS memory |
| range. |
| |
| - #size-cells: Must be set to 1. |
| |
| - ranges: Encodes CS to memory region association. |
| |
| - clocks: Clock feeding the EBI controller. |
| See clock-bindings.txt |
| |
| Children device nodes are representing device connected to the EBI bus. |
| |
| Required device node properties: |
| |
| - reg: Contains the chip-select id, the offset and the length |
| of the memory region requested by the device. |
| |
| EBI bus configuration will be defined directly in the device subnode. |
| |
| Optional EBI/SMC properties: |
| |
| - atmel,smc-bus-width: width of the asynchronous device's data bus |
| 8, 16 or 32. |
| Default to 8 when undefined. |
| |
| - atmel,smc-byte-access-type "write" or "select" (see Atmel datasheet). |
| Default to "select" when undefined. |
| |
| - atmel,smc-read-mode "nrd" or "ncs". |
| Default to "ncs" when undefined. |
| |
| - atmel,smc-write-mode "nwe" or "ncs". |
| Default to "ncs" when undefined. |
| |
| - atmel,smc-exnw-mode "disabled", "frozen" or "ready". |
| Default to "disabled" when undefined. |
| |
| - atmel,smc-page-mode enable page mode if present. The provided value |
| defines the page size (supported values: 4, 8, |
| 16 and 32). |
| |
| - atmel,smc-tdf-mode: "normal" or "optimized". When set to |
| "optimized" the data float time is optimized |
| depending on the next device being accessed |
| (next device setup time is subtracted to the |
| current device data float time). |
| Default to "normal" when undefined. |
| |
| If at least one atmel,smc- property is defined the following SMC timing |
| properties become mandatory. In the other hand, if none of the atmel,smc- |
| properties are specified, we assume that the EBI bus configuration will be |
| handled by the sub-device driver, and none of those properties should be |
| defined. |
| |
| All the timings are expressed in nanoseconds (see Atmel datasheet for a full |
| description). |
| |
| - atmel,smc-ncs-rd-setup-ns |
| - atmel,smc-nrd-setup-ns |
| - atmel,smc-ncs-wr-setup-ns |
| - atmel,smc-nwe-setup-ns |
| - atmel,smc-ncs-rd-pulse-ns |
| - atmel,smc-nrd-pulse-ns |
| - atmel,smc-ncs-wr-pulse-ns |
| - atmel,smc-nwe-pulse-ns |
| - atmel,smc-nwe-cycle-ns |
| - atmel,smc-nrd-cycle-ns |
| - atmel,smc-tdf-ns |
| |
| Example: |
| |
| ebi: ebi@10000000 { |
| compatible = "atmel,sama5d3-ebi"; |
| #address-cells = <2>; |
| #size-cells = <1>; |
| atmel,smc = <&hsmc>; |
| atmel,matrix = <&matrix>; |
| reg = <0x10000000 0x10000000 |
| 0x40000000 0x30000000>; |
| ranges = <0x0 0x0 0x10000000 0x10000000 |
| 0x1 0x0 0x40000000 0x10000000 |
| 0x2 0x0 0x50000000 0x10000000 |
| 0x3 0x0 0x60000000 0x10000000>; |
| clocks = <&mck>; |
| |
| pinctrl-names = "default"; |
| pinctrl-0 = <&pinctrl_ebi_addr>; |
| |
| nor: flash@0,0 { |
| compatible = "cfi-flash"; |
| #address-cells = <1>; |
| #size-cells = <1>; |
| reg = <0x0 0x0 0x1000000>; |
| bank-width = <2>; |
| |
| atmel,smc-read-mode = "nrd"; |
| atmel,smc-write-mode = "nwe"; |
| atmel,smc-bus-width = <16>; |
| atmel,smc-ncs-rd-setup-ns = <0>; |
| atmel,smc-ncs-wr-setup-ns = <0>; |
| atmel,smc-nwe-setup-ns = <8>; |
| atmel,smc-nrd-setup-ns = <16>; |
| atmel,smc-ncs-rd-pulse-ns = <84>; |
| atmel,smc-ncs-wr-pulse-ns = <84>; |
| atmel,smc-nrd-pulse-ns = <76>; |
| atmel,smc-nwe-pulse-ns = <76>; |
| atmel,smc-nrd-cycle-ns = <107>; |
| atmel,smc-nwe-cycle-ns = <84>; |
| atmel,smc-tdf-ns = <16>; |
| }; |
| }; |
| |