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+# 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>;
+ };
+ };