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authorRoger Quadros <rogerq@ti.com>2015-08-05 17:01:54 +0300
committerRoger Quadros <rogerq@ti.com>2016-04-15 11:54:03 +0300
commit3c76f6119a64eb8ff6d088ceb6ca03891e29a7ce (patch)
tree914d20cf705a1469fcc1181babefc276a68dfd6e /Documentation/devicetree/bindings/memory-controllers
parentbdd7e033fe4cc3836b141b75119a4a975a64d9bc (diff)
downloadlinux-3c76f6119a64eb8ff6d088ceb6ca03891e29a7ce.tar.bz2
memory: omap-gpmc: Move device tree binding to correct location
omap-gpmc.c is a memory controller so move the binding to the right place. Signed-off-by: Roger Quadros <rogerq@ti.com> Acked-by: Rob Herring <robh@kernel.org> Acked-by: Tony Lindgren <tony@atomide.com>
Diffstat (limited to 'Documentation/devicetree/bindings/memory-controllers')
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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.
+ - interrupt-controller: The GPMC driver implements and interrupt controller for
+ the NAND events "fifoevent" and "termcount".
+ The interrupt number mapping is as follows
+ 0 - NAND_fifoevent
+ 1 - NAND_termcount
+ - interrupt-cells: Must be set to 2
+
+Timing properties for child nodes. All are optional and default to 0.
+
+ - gpmc,sync-clk-ps: Minimum clock period for synchronous mode, in picoseconds
+
+ Chip-select signal timings (in nanoseconds) corresponding to GPMC_CONFIG2:
+ - gpmc,cs-on-ns: Assertion time
+ - gpmc,cs-rd-off-ns: Read deassertion time
+ - gpmc,cs-wr-off-ns: Write deassertion time
+
+ ADV signal timings (in nanoseconds) corresponding to GPMC_CONFIG3:
+ - gpmc,adv-on-ns: Assertion time
+ - gpmc,adv-rd-off-ns: Read deassertion time
+ - gpmc,adv-wr-off-ns: Write deassertion time
+ - gpmc,adv-aad-mux-on-ns: Assertion time for AAD
+ - gpmc,adv-aad-mux-rd-off-ns: Read deassertion time for AAD
+ - gpmc,adv-aad-mux-wr-off-ns: Write deassertion time for AAD
+
+ WE signals timings (in nanoseconds) corresponding to GPMC_CONFIG4:
+ - gpmc,we-on-ns Assertion time
+ - gpmc,we-off-ns: Deassertion time
+
+ OE signals timings (in nanoseconds) corresponding to GPMC_CONFIG4:
+ - gpmc,oe-on-ns: Assertion time
+ - gpmc,oe-off-ns: Deassertion time
+ - gpmc,oe-aad-mux-on-ns: Assertion time for AAD
+ - gpmc,oe-aad-mux-off-ns: Deassertion time for AAD
+
+ Access time and cycle time timings (in nanoseconds) corresponding to
+ GPMC_CONFIG5:
+ - gpmc,page-burst-access-ns: Multiple access word delay
+ - gpmc,access-ns: Start-cycle to first data valid delay
+ - gpmc,rd-cycle-ns: Total read cycle time
+ - gpmc,wr-cycle-ns: Total write cycle time
+ - gpmc,bus-turnaround-ns: Turn-around time between successive accesses
+ - gpmc,cycle2cycle-delay-ns: Delay between chip-select pulses
+ - gpmc,clk-activation-ns: GPMC clock activation time
+ - gpmc,wait-monitoring-ns: Start of wait monitoring with regard to valid
+ data
+
+Boolean timing parameters. If property is present parameter enabled and
+disabled if omitted:
+ - gpmc,adv-extra-delay: ADV signal is delayed by half GPMC clock
+ - gpmc,cs-extra-delay: CS signal is delayed by half GPMC clock
+ - gpmc,cycle2cycle-diffcsen: Add "cycle2cycle-delay" between successive
+ accesses to a different CS
+ - gpmc,cycle2cycle-samecsen: Add "cycle2cycle-delay" between successive
+ accesses to the same CS
+ - gpmc,oe-extra-delay: OE signal is delayed by half GPMC clock
+ - gpmc,we-extra-delay: WE signal is delayed by half GPMC clock
+ - gpmc,time-para-granularity: Multiply all access times by 2
+
+The following are only applicable to OMAP3+ and AM335x:
+ - gpmc,wr-access-ns: In synchronous write mode, for single or
+ burst accesses, defines the number of
+ GPMC_FCLK cycles from start access time
+ to the GPMC_CLK rising edge used by the
+ memory device for the first data capture.
+ - gpmc,wr-data-mux-bus-ns: In address-data multiplex mode, specifies
+ the time when the first data is driven on
+ the address-data bus.
+
+GPMC chip-select settings properties for child nodes. All are optional.
+
+- gpmc,burst-length Page/burst length. Must be 4, 8 or 16.
+- gpmc,burst-wrap Enables wrap bursting
+- gpmc,burst-read Enables read page/burst mode
+- gpmc,burst-write Enables write page/burst mode
+- gpmc,device-width Total width of device(s) connected to a GPMC
+ chip-select in bytes. The GPMC supports 8-bit
+ and 16-bit devices and so this property must be
+ 1 or 2.
+- gpmc,mux-add-data Address and data multiplexing configuration.
+ Valid values are 1 for address-address-data
+ multiplexing mode and 2 for address-data
+ multiplexing mode.
+- gpmc,sync-read Enables synchronous read. Defaults to asynchronous
+ is this is not set.
+- gpmc,sync-write Enables synchronous writes. Defaults to asynchronous
+ is this is not set.
+- gpmc,wait-pin Wait-pin used by client. Must be less than
+ "gpmc,num-waitpins".
+- gpmc,wait-on-read Enables wait monitoring on reads.
+- gpmc,wait-on-write Enables wait monitoring on writes.
+
+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 */
+ interrupt-controller;
+ #interrupt-cells = <2>;
+
+ /* child nodes go here */
+ };