dt-bindings: Add devicetree bindings

Add snapshot of device tree bindings from keystone common kernel, branch
"android-mainline-keystone-qcom-release" at c4c12103f9c0 ("Snap for 9228065
from e32903b9a63bb558df8b803b076619c53c16baad to
android-mainline-keystone-qcom-release").

Change-Id: I7682079615cbd9f29340a5c1f2a1d84ec441a1f1
Signed-off-by: Melody Olvera <quic_molvera@quicinc.com>

bindings/memory-controllers/ddr/jedec,lpddr2-timings.yaml

@@ -0,0 +1,135 @@
+# 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 <krzk@kernel.org>
+
+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>;
+    };