Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx> --- .../bindings/memory-controllers/atmel-ebi.txt | 153 +++++++++++++++++++++ 1 file changed, 153 insertions(+) create mode 100644 Documentation/devicetree/bindings/memory-controllers/atmel-ebi.txt diff --git a/Documentation/devicetree/bindings/memory-controllers/atmel-ebi.txt b/Documentation/devicetree/bindings/memory-controllers/atmel-ebi.txt new file mode 100644 index 0000000..dc2c34f --- /dev/null +++ b/Documentation/devicetree/bindings/memory-controllers/atmel-ebi.txt @@ -0,0 +1,153 @@ +* 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 though the SMC +(Static Memory Controller). +Synchronous memories (and some asynchronous memories like NANDs) can be +attached to specialized controllers which are responsible for configuring the +bus appropriately according to the connected device. +In the other hand, the bus interface can be automated for simple asynchronous +devices. + +Required properties: + +- compatible: "atmel,at91sam9260-ebi" + "atmel,at91sam9261-ebi" + "atmel,at91sam9263-ebi0" + "atmel,at91sam9263-ebi1" + "atmel,at91sam9g45-ebi" + "atmel,at91sam9x5-ebi" + "atmel,sama5d3-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 + +Child chip-select (cs) nodes contain the memory devices nodes connected to +such as NOR (e.g. cfi-flash) and NAND. +There might be board specific devices like FPGAs. +You'll define you device requirements in these child nodes. + +Required child cs node properties: + +- #address-cells: Must be 2. + +- #size-cells: Must be 1. + +- ranges: Empty property indicating that child nodes can inherit + memory layout. + +Optional child cs node properties: +- atmel,generic-dev boolean property specifying if the device is + a generic device. + The following properties are only parsed if + this property is present. + Specialized devices are attached to specialized + controllers which should configure the bus + appropriately. + +- atmel,bus-width: width of the asynchronous device's data bus + 8, 16 or 32. + 8 if not present. + +- atmel,byte-access-type "write" or "select" (see Atmel datasheet). + "select" if not present. + +- atmel,read-mode "nrd" or "ncs". + "ncs" is not present. + +- atmel,write-mode "nwe" or "ncs". + "ncs" is not present. + +- atmel,exnw-mode "disabled", "frozen" or "ready". + "disabled" if not present. + +- atmel,page-mode enable page mode if present. The provided value + defines the page size (supported values: 4, 8, + 16 and 32). + +Optional device timings expressed in nanoseconds (if the property is not +present 0 is assumed): + +- atmel,ncs-rd-setup-ns +- atmel,nrd-setup-ns +- atmel,ncs-wr-setup-ns +- atmel,nwe-setup-ns +- atmel,ncs-rd-pulse-ns +- atmel,nrd-pulse-ns +- atmel,ncs-wr-pulse-ns +- atmel,nwe-pulse-ns +- atmel,nwe-cycle-ns +- atmel,nrd-cycle-ns +- atmel,tdf-ns + +- atmel,tdf-optimized data float optimized mode. If present the data + float time is optimized depending on the next + device being accessed (next device setup + time is substracted to the current devive data + float time). + + + +Example: + + ebi: ebi@10000000 { + compatible = "atmel,sama5d3-ebi", "simple-bus"; + #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>; + + cs@0 { + #address-cells = <2>; + #size-cells = <1>; + ranges; + atmel,generic-dev; + atmel,read-mode = "nrd"; + atmel,write-mode = "nwe"; + atmel,bus-width = <16>; + atmel,ncs-rd-setup-ns = <0>; + atmel,ncs-wr-setup-ns = <0>; + atmel,nwe-setup-ns = <8>; + atmel,nrd-setup-ns = <16>; + atmel,ncs-rd-pulse-ns = <84>; + atmel,ncs-wr-pulse-ns = <84>; + atmel,nrd-pulse-ns = <76>; + atmel,nwe-pulse-ns = <76>; + atmel,nrd-cycle-ns = <107>; + atmel,nwe-cycle-ns = <84>; + atmel,tdf-ns = <16>; + + nor: flash@0,0 { + compatible = "cfi-flash"; + #address-cells = <1>; + #size-cells = <1>; + reg = <0x0 0x0 0x1000000>; + bank-width = <2>; + }; + }; + }; + -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html