76 lines
2.4 KiB
Plaintext
Executable file
76 lines
2.4 KiB
Plaintext
Executable file
* Ingenic JZ4780 NAND/external memory controller (NEMC)
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This file documents the device tree bindings for the NEMC external memory
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controller in Ingenic JZ4780
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Required properties:
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- compatible: Should be set to one of:
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"ingenic,jz4780-nemc" (JZ4780)
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- reg: Should specify the NEMC controller registers location and length.
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- clocks: Clock for the NEMC controller.
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- #address-cells: Must be set to 2.
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- #size-cells: Must be set to 1.
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- ranges: A set of ranges for each bank describing the physical memory layout.
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Each should specify the following 4 integer values:
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<cs number> 0 <physical address of mapping> <size of mapping>
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Each child of the NEMC node describes a device connected to the NEMC.
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Required child node properties:
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- reg: Should contain at least one register specifier, given in the following
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format:
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<cs number> <offset> <size>
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Multiple registers can be specified across multiple banks. This is needed,
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for example, for packaged NAND devices with multiple dies. Such devices
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should be grouped into a single node.
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Optional child node properties:
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- ingenic,nemc-bus-width: Specifies the bus width in bits. Defaults to 8 bits.
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- ingenic,nemc-tAS: Address setup time in nanoseconds.
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- ingenic,nemc-tAH: Address hold time in nanoseconds.
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- ingenic,nemc-tBP: Burst pitch time in nanoseconds.
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- ingenic,nemc-tAW: Access wait time in nanoseconds.
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- ingenic,nemc-tSTRV: Static memory recovery time in nanoseconds.
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If a child node references multiple banks in its "reg" property, the same value
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for all optional parameters will be configured for all banks. If any optional
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parameters are omitted, they will be left unchanged from whatever they are
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configured to when the NEMC device is probed (which may be the reset value as
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given in the hardware reference manual, or a value configured by the boot
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loader).
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Example (NEMC node with a NAND child device attached at CS1):
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nemc: nemc@13410000 {
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compatible = "ingenic,jz4780-nemc";
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reg = <0x13410000 0x10000>;
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#address-cells = <2>;
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#size-cells = <1>;
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ranges = <1 0 0x1b000000 0x1000000
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2 0 0x1a000000 0x1000000
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3 0 0x19000000 0x1000000
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4 0 0x18000000 0x1000000
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5 0 0x17000000 0x1000000
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6 0 0x16000000 0x1000000>;
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clocks = <&cgu JZ4780_CLK_NEMC>;
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nand: nand@1 {
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compatible = "ingenic,jz4780-nand";
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reg = <1 0 0x1000000>;
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ingenic,nemc-tAS = <10>;
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ingenic,nemc-tAH = <5>;
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ingenic,nemc-tBP = <10>;
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ingenic,nemc-tAW = <15>;
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ingenic,nemc-tSTRV = <100>;
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...
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};
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};
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