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+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: "http://devicetree.org/schemas/arm/stm32/st,mlahb.yaml#"
+$schema: "http://devicetree.org/meta-schemas/core.yaml#"
+
+title: STMicroelectronics STM32 ML-AHB interconnect bindings
+
+maintainers:
+ - Fabien Dessenne <fabien.dessenne@st.com>
+ - Arnaud Pouliquen <arnaud.pouliquen@st.com>
+
+description: |
+ These bindings describe the STM32 SoCs ML-AHB interconnect bus which connects
+ a Cortex-M subsystem with dedicated memories. The MCU SRAM and RETRAM memory
+ parts can be accessed through different addresses (see "RAM aliases" in [1])
+ using different buses (see [2]): balancing the Cortex-M firmware accesses
+ among those ports allows to tune the system performance.
+ [1]: https://www.st.com/resource/en/reference_manual/dm00327659.pdf
+ [2]: https://wiki.st.com/stm32mpu/wiki/STM32MP15_RAM_mapping
+
+allOf:
+ - $ref: /schemas/simple-bus.yaml#
+
+properties:
+ compatible:
+ contains:
+ enum:
+ - st,mlahb
+
+ dma-ranges:
+ description: |
+ Describe memory addresses translation between the local CPU and the
+ remote Cortex-M processor. Each memory region, is declared with
+ 3 parameters:
+ - param 1: device base address (Cortex-M processor address)
+ - param 2: physical base address (local CPU address)
+ - param 3: size of the memory region.
+ maxItems: 3
+
+ '#address-cells':
+ const: 1
+
+ '#size-cells':
+ const: 1
+
+required:
+ - compatible
+ - '#address-cells'
+ - '#size-cells'
+ - dma-ranges
+
+examples:
+ - |
+ mlahb: ahb {
+ compatible = "st,mlahb", "simple-bus";
+ #address-cells = <1>;
+ #size-cells = <1>;
+ reg = <0x10000000 0x40000>;
+ ranges;
+ dma-ranges = <0x00000000 0x38000000 0x10000>,
+ <0x10000000 0x10000000 0x60000>,
+ <0x30000000 0x30000000 0x60000>;
+
+ m4_rproc: m4@10000000 {
+ reg = <0x10000000 0x40000>;
+ };
+ };
+
+...