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+Device tree bindings for OMAP general purpose memory controllers (GPMC)
+
+The actual devices are instantiated from the child nodes of a GPMC node.
+
+Required properties:
+
+ - compatible: Should be set to one of the following:
+
+ ti,omap2420-gpmc (omap2420)
+ ti,omap2430-gpmc (omap2430)
+ ti,omap3430-gpmc (omap3430 & omap3630)
+ ti,omap4430-gpmc (omap4430 & omap4460 & omap543x)
+ ti,am3352-gpmc (am335x devices)
+
+ - reg: A resource specifier for the register space
+ (see the example below)
+ - ti,hwmods: Should be set to "ti,gpmc" until the DT transition is
+ completed.
+ - #address-cells: Must be set to 2 to allow memory address translation
+ - #size-cells: Must be set to 1 to allow CS address passing
+ - gpmc,num-cs: The maximum number of chip-select lines that controller
+ can support.
+ - gpmc,num-waitpins: The maximum number of wait pins that controller can
+ support.
+ - ranges: Must be set up to reflect the memory layout with four
+ integer values for each chip-select line in use:
+
+ <cs-number> 0 <physical address of mapping> <size>
+
+ Currently, calculated values derived from the contents
+ of the per-CS register GPMC_CONFIG7 (as set up by the
+ bootloader) are used for the physical address decoding.
+ As this will change in the future, filling correct
+ values here is a requirement.
+
+Timing properties for child nodes. All are optional and default to 0.
+
+ - gpmc,sync-clk: Minimum clock period for synchronous mode, in picoseconds
+
+ Chip-select signal timings corresponding to GPMC_CONFIG2:
+ - gpmc,cs-on: Assertion time
+ - gpmc,cs-rd-off: Read deassertion time
+ - gpmc,cs-wr-off: Write deassertion time
+
+ ADV signal timings corresponding to GPMC_CONFIG3:
+ - gpmc,adv-on: Assertion time
+ - gpmc,adv-rd-off: Read deassertion time
+ - gpmc,adv-wr-off: Write deassertion time
+
+ WE signals timings corresponding to GPMC_CONFIG4:
+ - gpmc,we-on: Assertion time
+ - gpmc,we-off: Deassertion time
+
+ OE signals timings corresponding to GPMC_CONFIG4:
+ - gpmc,oe-on: Assertion time
+ - gpmc,oe-off: Deassertion time
+
+ Access time and cycle time timings corresponding to GPMC_CONFIG5:
+ - gpmc,page-burst-access: Multiple access word delay
+ - gpmc,access: Start-cycle to first data valid delay
+ - gpmc,rd-cycle: Total read cycle time
+ - gpmc,wr-cycle: Total write cycle time
+
+The following are only applicable to OMAP3+ and AM335x:
+ - gpmc,wr-access
+ - gpmc,wr-data-mux-bus
+
+
+Example for an AM33xx board:
+
+ gpmc: gpmc@50000000 {
+ compatible = "ti,am3352-gpmc";
+ ti,hwmods = "gpmc";
+ reg = <0x50000000 0x2000>;
+ interrupts = <100>;
+
+ gpmc,num-cs = <8>;
+ gpmc,num-waitpins = <2>;
+ #address-cells = <2>;
+ #size-cells = <1>;
+ ranges = <0 0 0x08000000 0x10000000>; /* CS0 @addr 0x8000000, size 0x10000000 */
+
+ /* child nodes go here */
+ };