projects / linux-block.git / blame
| Commit | Line | Data |
|---|---|---|
| 34566e4f AP |
1 | # SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) |
| 2 | %YAML 1.2 | |
| 3 | --- | |
| 4 | $id: "http://devicetree.org/schemas/arm/stm32/st,mlahb.yaml#" | |
| 5 | $schema: "http://devicetree.org/meta-schemas/core.yaml#" | |
| 6 | ||
| 7 | title: STMicroelectronics STM32 ML-AHB interconnect bindings | |
| 8 | ||
| 9 | maintainers: | |
| 10 | - Fabien Dessenne <fabien.dessenne@st.com> | |
| 11 | - Arnaud Pouliquen <arnaud.pouliquen@st.com> | |
| 12 | ||
| 13 | description: | | |
| 14 | These bindings describe the STM32 SoCs ML-AHB interconnect bus which connects | |
| 15 | a Cortex-M subsystem with dedicated memories. The MCU SRAM and RETRAM memory | |
| 16 | parts can be accessed through different addresses (see "RAM aliases" in [1]) | |
| 17 | using different buses (see [2]): balancing the Cortex-M firmware accesses | |
| 18 | among those ports allows to tune the system performance. | |
| 19 | [1]: https://www.st.com/resource/en/reference_manual/dm00327659.pdf | |
| 20 | [2]: https://wiki.st.com/stm32mpu/wiki/STM32MP15_RAM_mapping | |
| 21 | ||
| 22 | allOf: | |
| 23 | - $ref: /schemas/simple-bus.yaml# | |
| 24 | ||
| 25 | properties: | |
| 26 | compatible: | |
| 27 | contains: | |
| 28 | enum: | |
| 29 | - st,mlahb | |
| 30 | ||
| 31 | dma-ranges: | |
| 32 | description: | | |
| 33 | Describe memory addresses translation between the local CPU and the | |
| 34 | remote Cortex-M processor. Each memory region, is declared with | |
| 35 | 3 parameters: | |
| 36 | - param 1: device base address (Cortex-M processor address) | |
| 37 | - param 2: physical base address (local CPU address) | |
| 38 | - param 3: size of the memory region. | |
| 39 | maxItems: 3 | |
| 40 | ||
| 41 | '#address-cells': | |
| 42 | const: 1 | |
| 43 | ||
| 44 | '#size-cells': | |
| 45 | const: 1 | |
| 46 | ||
| 47 | required: | |
| 48 | - compatible | |
| 49 | - '#address-cells' | |
| 50 | - '#size-cells' | |
| 51 | - dma-ranges | |
| 52 | ||
| 53 | examples: | |
| 54 | - | | |
| 51a21e0e | 55 | mlahb: ahb@38000000 { |
| 34566e4f AP |
56 | compatible = "st,mlahb", "simple-bus"; |
| 57 | #address-cells = <1>; | |
| 58 | #size-cells = <1>; | |
| 59 | reg = <0x10000000 0x40000>; | |
| 60 | ranges; | |
| 61 | dma-ranges = <0x00000000 0x38000000 0x10000>, | |
| 62 | <0x10000000 0x10000000 0x60000>, | |
| 63 | <0x30000000 0x30000000 0x60000>; | |
| 64 | ||
| 65 | m4_rproc: m4@10000000 { | |
| 66 | reg = <0x10000000 0x40000>; | |
| 67 | }; | |
| 68 | }; | |
| 69 | ||
| 70 | ... |