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v0.7.0
v0.7.0
https://github.com/torvalds/linux
Tip revision: f8788d86ab28f61f7b46eb6be375f8a726783636 authored by Linus Torvalds on 24 February 2020, 00:17:42 UTC
Linux 5.6-rc3
Linux 5.6-rc3
Tip revision: f8788d8
gpmc-nor.txt
Device tree bindings for NOR flash connect to TI GPMC
NOR flash connected to the TI GPMC (found on OMAP boards) are represented as
child nodes of the GPMC controller with a name of "nor".
All timing relevant properties as well as generic GPMC child properties are
explained in a separate documents. Please refer to
Documentation/devicetree/bindings/memory-controllers/omap-gpmc.txt
Required properties:
- bank-width: Width of NOR flash in bytes. GPMC supports 8-bit and
16-bit devices and so must be either 1 or 2 bytes.
- compatible: Documentation/devicetree/bindings/mtd/mtd-physmap.txt
- gpmc,cs-on-ns: Chip-select assertion time
- gpmc,cs-rd-off-ns: Chip-select de-assertion time for reads
- gpmc,cs-wr-off-ns: Chip-select de-assertion time for writes
- gpmc,oe-on-ns: Output-enable assertion time
- gpmc,oe-off-ns: Output-enable de-assertion time
- gpmc,we-on-ns Write-enable assertion time
- gpmc,we-off-ns: Write-enable de-assertion time
- gpmc,access-ns: Start cycle to first data capture (read access)
- gpmc,rd-cycle-ns: Total read cycle time
- gpmc,wr-cycle-ns: Total write cycle time
- linux,mtd-name: Documentation/devicetree/bindings/mtd/mtd-physmap.txt
- reg: Chip-select, base address (relative to chip-select)
and size of NOR flash. Note that base address will be
typically 0 as this is the start of the chip-select.
Optional properties:
- gpmc,XXX Additional GPMC timings and settings parameters. See
Documentation/devicetree/bindings/memory-controllers/omap-gpmc.txt
Optional properties for partition table parsing:
- #address-cells: should be set to 1
- #size-cells: should be set to 1
Example:
gpmc: gpmc@6e000000 {
compatible = "ti,omap3430-gpmc", "simple-bus";
ti,hwmods = "gpmc";
reg = <0x6e000000 0x1000>;
interrupts = <20>;
gpmc,num-cs = <8>;
gpmc,num-waitpins = <4>;
#address-cells = <2>;
#size-cells = <1>;
ranges = <0 0 0x10000000 0x08000000>;
nor@0,0 {
compatible = "cfi-flash";
linux,mtd-name= "intel,pf48f6000m0y1be";
#address-cells = <1>;
#size-cells = <1>;
reg = <0 0 0x08000000>;
bank-width = <2>;
gpmc,mux-add-data;
gpmc,cs-on-ns = <0>;
gpmc,cs-rd-off-ns = <186>;
gpmc,cs-wr-off-ns = <186>;
gpmc,adv-on-ns = <12>;
gpmc,adv-rd-off-ns = <48>;
gpmc,adv-wr-off-ns = <48>;
gpmc,oe-on-ns = <54>;
gpmc,oe-off-ns = <168>;
gpmc,we-on-ns = <54>;
gpmc,we-off-ns = <168>;
gpmc,rd-cycle-ns = <186>;
gpmc,wr-cycle-ns = <186>;
gpmc,access-ns = <114>;
gpmc,page-burst-access-ns = <6>;
gpmc,bus-turnaround-ns = <12>;
gpmc,cycle2cycle-delay-ns = <18>;
gpmc,wr-data-mux-bus-ns = <90>;
gpmc,wr-access-ns = <186>;
gpmc,cycle2cycle-samecsen;
gpmc,cycle2cycle-diffcsen;
partition@0 {
label = "bootloader-nor";
reg = <0 0x40000>;
};
partition@40000 {
label = "params-nor";
reg = <0x40000 0x40000>;
};
partition@80000 {
label = "kernel-nor";
reg = <0x80000 0x200000>;
};
partition@280000 {
label = "filesystem-nor";
reg = <0x240000 0x7d80000>;
};
};
};