[PATCH v1 2/9] dt-bindings: memory: Document Tegra114 Memory Controller

Svyatoslav Ryhel posted 9 patches 11 months, 2 weeks ago
There is a newer version of this series
[PATCH v1 2/9] dt-bindings: memory: Document Tegra114 Memory Controller
Posted by Svyatoslav Ryhel 11 months, 2 weeks ago
Provided schema is based on existing Tegra124 MC schema. The most notable
difference is the amount of EMEM timings.

Signed-off-by: Svyatoslav Ryhel <clamor95@gmail.com>
---
 .../nvidia,tegra114-mc.yaml                   | 154 ++++++++++++++++++
 1 file changed, 154 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/memory-controllers/nvidia,tegra114-mc.yaml

diff --git a/Documentation/devicetree/bindings/memory-controllers/nvidia,tegra114-mc.yaml b/Documentation/devicetree/bindings/memory-controllers/nvidia,tegra114-mc.yaml
new file mode 100644
index 000000000000..d69fd5211f96
--- /dev/null
+++ b/Documentation/devicetree/bindings/memory-controllers/nvidia,tegra114-mc.yaml
@@ -0,0 +1,154 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/memory-controllers/nvidia,tegra114-mc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: NVIDIA Tegra114 SoC Memory Controller
+
+maintainers:
+  - Svyatoslav Ryhel <clamor95@gmail.com>
+
+description:
+  Tegra114 SoC features a hybrid 2x32-bit / 1x64-bit memory controller similar
+  to one found in Tegra 124. These are interleaved to provide high performance
+  with the load shared across two memory channels. The Tegra114 Memory Controller
+  handles memory requests from internal clients and arbitrates among them to
+  allocate memory bandwidth for DDR3L and LPDDR3 SDRAMs.
+
+properties:
+  compatible:
+    const: nvidia,tegra114-mc
+
+  reg:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+
+  clock-names:
+    items:
+      - const: mc
+
+  interrupts:
+    maxItems: 1
+
+  "#reset-cells":
+    const: 1
+
+  "#iommu-cells":
+    const: 1
+
+  "#interconnect-cells":
+    const: 1
+
+patternProperties:
+  "^emc-timings-[0-9]+$":
+    type: object
+    properties:
+      nvidia,ram-code:
+        $ref: /schemas/types.yaml#/definitions/uint32
+        description:
+          Value of RAM_CODE this timing set is used for.
+
+    patternProperties:
+      "^timing-[0-9]+$":
+        type: object
+        properties:
+          clock-frequency:
+            description:
+              Memory clock rate in Hz.
+            minimum: 1000000
+            maximum: 1066000000
+
+          nvidia,emem-configuration:
+            $ref: /schemas/types.yaml#/definitions/uint32-array
+            description: |
+              Values to be written to the EMEM register block. See section
+              "20.11.1 MC Registers" in the TRM.
+            items:
+              - description: MC_EMEM_ARB_CFG
+              - description: MC_EMEM_ARB_OUTSTANDING_REQ
+              - description: MC_EMEM_ARB_TIMING_RCD
+              - description: MC_EMEM_ARB_TIMING_RP
+              - description: MC_EMEM_ARB_TIMING_RC
+              - description: MC_EMEM_ARB_TIMING_RAS
+              - description: MC_EMEM_ARB_TIMING_FAW
+              - description: MC_EMEM_ARB_TIMING_RRD
+              - description: MC_EMEM_ARB_TIMING_RAP2PRE
+              - description: MC_EMEM_ARB_TIMING_WAP2PRE
+              - description: MC_EMEM_ARB_TIMING_R2R
+              - description: MC_EMEM_ARB_TIMING_W2W
+              - description: MC_EMEM_ARB_TIMING_R2W
+              - description: MC_EMEM_ARB_TIMING_W2R
+              - description: MC_EMEM_ARB_DA_TURNS
+              - description: MC_EMEM_ARB_DA_COVERS
+              - description: MC_EMEM_ARB_MISC0
+              - description: MC_EMEM_ARB_RING1_THROTTLE
+
+        required:
+          - clock-frequency
+          - nvidia,emem-configuration
+
+        additionalProperties: false
+
+    required:
+      - nvidia,ram-code
+
+    additionalProperties: false
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - clocks
+  - clock-names
+  - "#reset-cells"
+  - "#iommu-cells"
+  - "#interconnect-cells"
+
+additionalProperties: false
+
+examples:
+  - |
+    memory-controller@70019000 {
+        compatible = "nvidia,tegra114-mc";
+        reg = <0x70019000 0x1000>;
+        clocks = <&tegra_car 32>;
+        clock-names = "mc";
+
+        interrupts = <0 77 4>;
+
+        #iommu-cells = <1>;
+        #reset-cells = <1>;
+        #interconnect-cells = <1>;
+
+        emc-timings-0 {
+            nvidia,ram-code = <0>;
+
+            timing-12750000 {
+                clock-frequency = <12750000>;
+
+                nvidia,emem-configuration = <
+                    0x40040001 /* MC_EMEM_ARB_CFG */
+                    0x8000003f /* MC_EMEM_ARB_OUTSTANDING_REQ */
+                    0x00000001 /* MC_EMEM_ARB_TIMING_RCD */
+                    0x00000001 /* MC_EMEM_ARB_TIMING_RP */
+                    0x00000002 /* MC_EMEM_ARB_TIMING_RC */
+                    0x00000000 /* MC_EMEM_ARB_TIMING_RAS */
+                    0x00000001 /* MC_EMEM_ARB_TIMING_FAW */
+                    0x00000001 /* MC_EMEM_ARB_TIMING_RRD */
+                    0x00000002 /* MC_EMEM_ARB_TIMING_RAP2PRE */
+                    0x00000008 /* MC_EMEM_ARB_TIMING_WAP2PRE */
+                    0x00000002 /* MC_EMEM_ARB_TIMING_R2R */
+                    0x00000001 /* MC_EMEM_ARB_TIMING_W2W */
+                    0x00000003 /* MC_EMEM_ARB_TIMING_R2W */
+                    0x00000006 /* MC_EMEM_ARB_TIMING_W2R */
+                    0x06030102 /* MC_EMEM_ARB_DA_TURNS */
+                    0x000a0402 /* MC_EMEM_ARB_DA_COVERS */
+                    0x77e30303 /* MC_EMEM_ARB_MISC0 */
+                    0x001f0000 /* MC_EMEM_ARB_RING1_THROTTLE */
+                >;
+            };
+        };
+    };
-- 
2.43.0
Re: [PATCH v1 2/9] dt-bindings: memory: Document Tegra114 Memory Controller
Posted by Krzysztof Kozlowski 11 months, 2 weeks ago
On 25/02/2025 15:34, Svyatoslav Ryhel wrote:
> +
> +properties:
> +  compatible:
> +    const: nvidia,tegra114-mc
> +
> +  reg:
> +    maxItems: 1
> +
> +  clocks:
> +    maxItems: 1
> +
> +  clock-names:
> +    items:
> +      - const: mc

Drop clock-names, not really useful if it copies device name.

> +
> +  interrupts:
> +    maxItems: 1
> +
> +  "#reset-cells":
> +    const: 1
> +
> +  "#iommu-cells":
> +    const: 1
> +
> +  "#interconnect-cells":
> +    const: 1
> +
> +patternProperties:
> +  "^emc-timings-[0-9]+$":
> +    type: object
> +    properties:
> +      nvidia,ram-code:
> +        $ref: /schemas/types.yaml#/definitions/uint32
> +        description:
> +          Value of RAM_CODE this timing set is used for.

This spreads to multiple bindings now. This really needs to be in shared
schema.

> +
> +    patternProperties:
> +      "^timing-[0-9]+$":
> +        type: object
> +        properties:
> +          clock-frequency:
> +            description:
> +              Memory clock rate in Hz.
> +            minimum: 1000000
> +            maximum: 1066000000

clock-frequency is a legacy property, not really desired for new
bindings. Memory controllers can operate with different speed, so how do
you factor this here?

BTW, same review could have been given last time and you will be deemed
to repeat everything, unless this is captured in description or commit msg.

Best regards,
Krzysztof