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Diffstat (limited to 'Documentation/devicetree/bindings/sram/sram.yaml')
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diff --git a/Documentation/devicetree/bindings/sram/sram.yaml b/Documentation/devicetree/bindings/sram/sram.yaml new file mode 100644 index 000000000000..34803ea4f0b1 --- /dev/null +++ b/Documentation/devicetree/bindings/sram/sram.yaml @@ -0,0 +1,136 @@ +# SPDX-License-Identifier: GPL-2.0 +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/sram/sram.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: Generic on-chip SRAM + +maintainers: + - Rob Herring <robh@kernel.org> + +description: |+ + Simple IO memory regions to be managed by the genalloc API. + + Each child of the sram node specifies a region of reserved memory. Each + child node should use a 'reg' property to specify a specific range of + reserved memory. + + Following the generic-names recommended practice, node names should + reflect the purpose of the node. Unit address (@<address>) should be + appended to the name. + +properties: + $nodename: + pattern: "^sram(@.*)?" + + compatible: + contains: + enum: + - mmio-sram + - atmel,sama5d2-securam + + reg: + maxItems: 1 + + clocks: + description: + A list of phandle and clock specifier pair that controls the single + SRAM clock. + + "#address-cells": + const: 1 + + "#size-cells": + const: 1 + + ranges: + description: + Should translate from local addresses within the sram to bus addresses. + + no-memory-wc: + description: + The flag indicating, that SRAM memory region has not to be remapped + as write combining. WC is used by default. + type: boolean + +patternProperties: + "^([a-z]*-)?sram@[a-f0-9]+$": + type: object + description: + Each child of the sram node specifies a region of reserved memory. + properties: + compatible: + description: + Should contain a vendor specific string in the form + <vendor>,[<device>-]<usage> + + reg: + description: + IO mem address range, relative to the SRAM range. + maxItems: 1 + + pool: + description: + Indicates that the particular reserved SRAM area is addressable + and in use by another device or devices. + type: boolean + + export: + description: + Indicates that the reserved SRAM area may be accessed outside + of the kernel, e.g. by bootloader or userspace. + type: boolean + + protect-exec: + description: | + Same as 'pool' above but with the additional constraint that code + will be run from the region and that the memory is maintained as + read-only, executable during code execution. NOTE: This region must + be page aligned on start and end in order to properly allow + manipulation of the page attributes. + type: boolean + + label: + description: + The name for the reserved partition, if omitted, the label is taken + from the node name excluding the unit address. + + required: + - reg + + additionalProperties: false + +required: + - compatible + - reg + - "#address-cells" + - "#size-cells" + - ranges + +additionalProperties: false + +examples: + - | + sram@5c000000 { + compatible = "mmio-sram"; + reg = <0x5c000000 0x40000>; /* 256 KiB SRAM at address 0x5c000000 */ + + #address-cells = <1>; + #size-cells = <1>; + ranges = <0 0x5c000000 0x40000>; + + smp-sram@100 { + reg = <0x100 0x50>; + }; + + device-sram@1000 { + reg = <0x1000 0x1000>; + pool; + }; + + exported-sram@20000 { + reg = <0x20000 0x20000>; + export; + }; + }; |