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Diffstat (limited to 'Documentation/devicetree/bindings/memory-controllers/ddr/jedec,lpddr3-timings.yaml')
-rw-r--r-- | Documentation/devicetree/bindings/memory-controllers/ddr/jedec,lpddr3-timings.yaml | 157 |
1 files changed, 157 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/memory-controllers/ddr/jedec,lpddr3-timings.yaml b/Documentation/devicetree/bindings/memory-controllers/ddr/jedec,lpddr3-timings.yaml new file mode 100644 index 000000000000..97c3e988af5f --- /dev/null +++ b/Documentation/devicetree/bindings/memory-controllers/ddr/jedec,lpddr3-timings.yaml @@ -0,0 +1,157 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/memory-controllers/ddr/jedec,lpddr3-timings.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: LPDDR3 SDRAM AC timing parameters for a given speed-bin + +maintainers: + - Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com> + +properties: + compatible: + const: jedec,lpddr3-timings + + reg: + maxItems: 1 + description: | + Maximum DDR clock frequency for the speed-bin, in Hz. + Property is deprecated, use max-freq. + deprecated: true + + max-freq: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Maximum DDR clock frequency for the speed-bin, in Hz. + + min-freq: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Minimum DDR clock frequency for the speed-bin, in Hz. + + tCKE: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + CKE minimum pulse width (HIGH and LOW pulse width) in pico seconds. + + tCKESR: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + CKE minimum pulse width during SELF REFRESH (low pulse width during + SELF REFRESH) in pico seconds. + + tFAW: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Four-bank activate window in pico seconds. + + tMRD: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Mode register set command delay in pico seconds. + + tR2R-C2C: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Additional READ-to-READ delay in chip-to-chip cases in pico seconds. + + tRAS: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Row active time in pico seconds. + + tRC: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + ACTIVATE-to-ACTIVATE command period in pico seconds. + + tRCD: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + RAS-to-CAS delay in pico seconds. + + tRFC: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Refresh Cycle time in pico seconds. + + tRPab: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Row precharge time (all banks) in pico seconds. + + tRPpb: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Row precharge time (single banks) in pico seconds. + + tRRD: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Active bank A to active bank B in pico seconds. + + tRTP: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Internal READ to PRECHARGE command delay in pico seconds. + + tW2W-C2C: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Additional WRITE-to-WRITE delay in chip-to-chip cases in pico seconds. + + tWR: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + WRITE recovery time in pico seconds. + + tWTR: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Internal WRITE-to-READ command delay in pico seconds. + + tXP: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Exit power-down to next valid command delay in pico seconds. + + tXSR: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + SELF REFRESH exit to next valid command delay in pico seconds. + +required: + - compatible + - min-freq + - max-freq + +additionalProperties: false + +examples: + - | + lpddr3 { + timings { + compatible = "jedec,lpddr3-timings"; + max-freq = <800000000>; + min-freq = <100000000>; + tCKE = <3750>; + tCKESR = <3750>; + tFAW = <25000>; + tMRD = <7000>; + tR2R-C2C = <0>; + tRAS = <23000>; + tRC = <33750>; + tRCD = <10000>; + tRFC = <65000>; + tRPab = <12000>; + tRPpb = <12000>; + tRRD = <6000>; + tRTP = <3750>; + tW2W-C2C = <0>; + tWR = <7500>; + tWTR = <3750>; + tXP = <3750>; + tXSR = <70000>; + }; + }; |