[PATCH v3 2/8] dt-bindings: memory: lpddr3-timings: convert to dtschema
Krzysztof Kozlowski
krzysztof.kozlowski at canonical.com
Sun Feb 6 05:58:01 PST 2022
Convert the LPDDR3 memory timings bindings to DT schema format.
Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski at canonical.com>
Reviewed-by: Dmitry Osipenko <digetx at gmail.com>
---
.../ddr/jedec,lpddr3-timings.yaml | 153 ++++++++++++++++++
.../memory-controllers/ddr/lpddr3-timings.txt | 58 -------
2 files changed, 153 insertions(+), 58 deletions(-)
create mode 100644 Documentation/devicetree/bindings/memory-controllers/ddr/jedec,lpddr3-timings.yaml
delete mode 100644 Documentation/devicetree/bindings/memory-controllers/ddr/lpddr3-timings.txt
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..98bc219e8a25
--- /dev/null
+++ b/Documentation/devicetree/bindings/memory-controllers/ddr/jedec,lpddr3-timings.yaml
@@ -0,0 +1,153 @@
+# 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 at canonical.com>
+
+properties:
+ compatible:
+ const: jedec,lpddr3-timings
+
+ reg:
+ maxItems: 1
+ 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
+ - reg
+
+additionalProperties: false
+
+examples:
+ - |
+ lpddr3 {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ timings at 800000000 {
+ compatible = "jedec,lpddr3-timings";
+ reg = <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>;
+ };
+ };
diff --git a/Documentation/devicetree/bindings/memory-controllers/ddr/lpddr3-timings.txt b/Documentation/devicetree/bindings/memory-controllers/ddr/lpddr3-timings.txt
deleted file mode 100644
index 84705e50a3fd..000000000000
--- a/Documentation/devicetree/bindings/memory-controllers/ddr/lpddr3-timings.txt
+++ /dev/null
@@ -1,58 +0,0 @@
-* AC timing parameters of LPDDR3 memories for a given speed-bin.
-
-The structures are based on LPDDR2 and extended where needed.
-
-Required properties:
-- compatible : Should be "jedec,lpddr3-timings"
-- min-freq : minimum DDR clock frequency for the speed-bin. Type is <u32>
-- reg : maximum DDR clock frequency for the speed-bin. Type is <u32>
-
-Optional properties:
-
-The following properties represent AC timing parameters from the memory
-data-sheet of the device for a given speed-bin. All these properties are
-of type <u32> and the default unit is ps (pico seconds).
-- tRFC
-- tRRD
-- tRPab
-- tRPpb
-- tRCD
-- tRC
-- tRAS
-- tWTR
-- tWR
-- tRTP
-- tW2W-C2C
-- tR2R-C2C
-- tFAW
-- tXSR
-- tXP
-- tCKE
-- tCKESR
-- tMRD
-
-Example:
-
-timings_samsung_K3QF2F20DB_800mhz: lpddr3-timings at 800000000 {
- compatible = "jedec,lpddr3-timings";
- reg = <800000000>; /* workaround: it shows max-freq */
- min-freq = <100000000>;
- tRFC = <65000>;
- tRRD = <6000>;
- tRPab = <12000>;
- tRPpb = <12000>;
- tRCD = <10000>;
- tRC = <33750>;
- tRAS = <23000>;
- tWTR = <3750>;
- tWR = <7500>;
- tRTP = <3750>;
- tW2W-C2C = <0>;
- tR2R-C2C = <0>;
- tFAW = <25000>;
- tXSR = <70000>;
- tXP = <3750>;
- tCKE = <3750>;
- tCKESR = <3750>;
- tMRD = <7000>;
-};
--
2.32.0
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