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| author | Mark Brown | 2022-02-21 15:22:33 +0000 |
|---|---|---|
| committer | Mark Brown | 2022-02-21 15:22:33 +0000 |
| commit | f89504300e94524d5d5846ff8b728592ac72cec4 (patch) | |
| tree | 4559a9e40704769a569cc5390027a11f589b7824 /Documentation | |
| parent | c5a3106aa4923bec979c2a76667a493cb5d134fd (diff) | |
| parent | eba5368503b4291db7819512600fa014ea17c5a8 (diff) | |
spi: Stacked/parallel memories bindings
Merge series from Miquel Raynal <miquel.raynal@bootlin.com>:
DT bindings for stacked and parallel flash/memory devices.
base-commit: e783362eb54cd99b2cac8b3a9aeac942e6f6ac07
Diffstat (limited to 'Documentation')
3 files changed, 34 insertions, 1 deletions
diff --git a/Documentation/devicetree/bindings/mtd/jedec,spi-nor.yaml b/Documentation/devicetree/bindings/mtd/jedec,spi-nor.yaml index 39421f7233e4..4abfb4cfc157 100644 --- a/Documentation/devicetree/bindings/mtd/jedec,spi-nor.yaml +++ b/Documentation/devicetree/bindings/mtd/jedec,spi-nor.yaml @@ -47,7 +47,8 @@ properties: identified by the JEDEC READ ID opcode (0x9F). reg: - maxItems: 1 + minItems: 1 + maxItems: 2 spi-max-frequency: true spi-rx-bus-width: true diff --git a/Documentation/devicetree/bindings/spi/spi-controller.yaml b/Documentation/devicetree/bindings/spi/spi-controller.yaml index 36b72518f565..0f4d40218400 100644 --- a/Documentation/devicetree/bindings/spi/spi-controller.yaml +++ b/Documentation/devicetree/bindings/spi/spi-controller.yaml @@ -139,4 +139,11 @@ examples: spi-max-frequency = <100000>; reg = <1>; }; + + flash@2 { + compatible = "jedec,spi-nor"; + spi-max-frequency = <50000000>; + reg = <2>, <3>; + stacked-memories = /bits/ 64 <0x10000000 0x10000000>; + }; }; diff --git a/Documentation/devicetree/bindings/spi/spi-peripheral-props.yaml b/Documentation/devicetree/bindings/spi/spi-peripheral-props.yaml index 3ec2d7b83775..f3f06036e611 100644 --- a/Documentation/devicetree/bindings/spi/spi-peripheral-props.yaml +++ b/Documentation/devicetree/bindings/spi/spi-peripheral-props.yaml @@ -83,6 +83,31 @@ properties: description: Delay, in microseconds, after a write transfer. + stacked-memories: + description: Several SPI memories can be wired in stacked mode. + This basically means that either a device features several chip + selects, or that different devices must be seen as a single + bigger chip. This basically doubles (or more) the total address + space with only a single additional wire, while still needing + to repeat the commands when crossing a chip boundary. The size of + each chip should be provided as members of the array. + $ref: /schemas/types.yaml#/definitions/uint64-array + minItems: 2 + maxItems: 4 + + parallel-memories: + description: Several SPI memories can be wired in parallel mode. + The devices are physically on a different buses but will always + act synchronously as each data word is spread across the + different memories (eg. even bits are stored in one memory, odd + bits in the other). This basically doubles the address space and + the throughput while greatly complexifying the wiring because as + many busses as devices must be wired. The size of each chip should + be provided as members of the array. + $ref: /schemas/types.yaml#/definitions/uint64-array + minItems: 2 + maxItems: 4 + # The controller specific properties go here. allOf: - $ref: cdns,qspi-nor-peripheral-props.yaml# |