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+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/memory-controllers/ddr/jedec,lpddr2-timings.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: LPDDR2 SDRAM AC timing parameters for a given speed-bin
+
+maintainers:
+ - Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
+
+properties:
+ compatible:
+ const: jedec,lpddr2-timings
+
+ 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.
+
+ tCKESR:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description: |
+ CKE minimum pulse width during SELF REFRESH (low pulse width during
+ SELF REFRESH) in pico seconds.
+
+ tDQSCK-max:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description: |
+ DQS output data access time from CK_t/CK_c in pico seconds.
+
+ tDQSCK-max-derated:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description: |
+ DQS output data access time from CK_t/CK_c, temperature de-rated, in pico
+ seconds.
+
+ tFAW:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description: |
+ Four-bank activate window in pico seconds.
+
+ tRAS-max-ns:
+ description: |
+ Row active time in nano seconds.
+
+ tRAS-min:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description: |
+ Row active time in pico seconds.
+
+ tRCD:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description: |
+ RAS-to-CAS delay in pico seconds.
+
+ tRPab:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description: |
+ Row precharge time (all 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.
+
+ 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.
+
+ tZQCL:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description: |
+ Long calibration time in pico seconds.
+
+ tZQCS:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description: |
+ Short calibration time in pico seconds.
+
+ tZQinit:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description: |
+ Initialization calibration time in pico seconds.
+
+required:
+ - compatible
+ - min-freq
+ - max-freq
+
+additionalProperties: false
+
+examples:
+ - |
+ timings {
+ compatible = "jedec,lpddr2-timings";
+ min-freq = <10000000>;
+ max-freq = <400000000>;
+ tCKESR = <15000>;
+ tDQSCK-max = <5500>;
+ tFAW = <50000>;
+ tRAS-max-ns = <70000>;
+ tRAS-min = <42000>;
+ tRPab = <21000>;
+ tRCD = <18000>;
+ tRRD = <10000>;
+ tRTP = <7500>;
+ tWR = <15000>;
+ tWTR = <7500>;
+ tXP = <7500>;
+ tZQCL = <360000>;
+ tZQCS = <90000>;
+ tZQinit = <1000000>;
+ };