xref: /linux/Documentation/devicetree/bindings/remoteproc/amd,bram-rproc.yaml (revision fc710de0dd25ed50a087833b4171eb1a46737a9e)

# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
%YAML 1.2
---
$id: http://devicetree.org/schemas/remoteproc/amd,bram-rproc.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#

title: AMD MicroBlaze/V BRAM-based Remote Processor

maintainers:
  - Ben Levinsky <ben.levinsky@amd.com>

description: |
  Soft-core processor subsystem instantiated in AMD programmable logic and
  using dual-port BRAM for firmware storage and execution.

  Hardware Architecture:

    Host (PS)                        Programmable Logic (PL)
    =========                        ======================

    AXI Interface -----------------> AXI BRAM Controller (Host Port)
                                             |
                                             | Port A
                                             v
                                     +-----------------+
                                     |  Dual-Port BRAM |
                                     | (shared memory) |
                                     +-----------------+
                                             ^
                                             | Port B
                                             |
                                     AXI BRAM Controller (Soft-core Port)
                                             ^
                                             | LMB
                                             |
                                     Soft-core CPU (MicroBlaze/V)

    GPIO --------------------------> Proc Sys Reset ----> CPU Reset Signal

    Clock -------------------------> Clock Distribution -> CPU Clock

  Memory Architecture:

    The dual-port BRAM allows simultaneous access from both processors:
      - Port A: Connected to the host AXI BRAM controller for firmware loading
      - Port B: Connected to the soft-core local memory bus for execution

  The reg property describes the executable BRAM window in the processor-local
  address space. The parent bus node translates that window to the system
  physical address space by using standard devicetree address translation
  through ranges. A clock input and a reset GPIO control the subsystem.

properties:
  compatible:
    oneOf:
      - const: xlnx,zynqmp-bram-rproc
      - items:
          - enum:
              - amd,versal2-bram-rproc
              - xlnx,versal-bram-rproc
              - xlnx,versal-net-bram-rproc
          - const: xlnx,zynqmp-bram-rproc

  reg:
    maxItems: 1
    description:
      Processor-local address and size of the BRAM firmware memory window,
      as seen by the soft-core processor (typically 0x0 for reset vector).
      The parent bus ranges property must translate this window to the
      corresponding system physical address.

  clocks:
    maxItems: 1
    description:
      Clock input for the soft-core processor subsystem.

  firmware-name:
    maxItems: 1
    description:
      Name of the firmware ELF file to load.

  reset-gpios:
    maxItems: 1
    description:
      GPIO specifier controlling the soft-core reset input.

required:
  - compatible
  - reg
  - clocks
  - reset-gpios

additionalProperties: false

examples:
  - |
    #include <dt-bindings/gpio/gpio.h>
    remoteproc@0 {
      compatible = "xlnx,zynqmp-bram-rproc";
      reg = <0x0 0x40000>;
      clocks = <&pl_clk>;
      firmware-name = "firmware.elf";
      reset-gpios = <&gpio0 0 GPIO_ACTIVE_LOW>;
    };
...