Re: [PATCH v19 4/5] dt-bindings: remoteproc: Add documentation for ZynqMP R5 rproc bindings

From: Mathieu Poirier
Date: Thu Oct 29 2020 - 18:53:09 EST


On Mon, Oct 19, 2020 at 03:40:06PM -0700, Ben Levinsky wrote:
> Add binding for ZynqMP R5 OpenAMP.
>
> Represent the RPU domain resources in one device node. Each RPU
> processor is a subnode of the top RPU domain node.
>
> Signed-off-by: Jason Wu <j.wu@xxxxxxxxxx>
> Signed-off-by: Wendy Liang <jliang@xxxxxxxxxx>
> Signed-off-by: Michal Simek <michal.simek@xxxxxxxxxx>
> Signed-off-by: Ben Levinsky <ben.levinsky@xxxxxxxxxx>
> ---
> v3:
> - update zynqmp_r5 yaml parsing to not raise warnings for extra
> information in children of R5 node. The warning "node has a unit
> name, but no reg or ranges property" will still be raised though
> as this particular node is needed to describe the
> '#address-cells' and '#size-cells' information.
> v4::
> - remove warning '/example-0/rpu@ff9a0000/r5@0:
> node has a unit name, but no reg or ranges property'
> by adding reg to r5 node.
> v5:
> - update device tree sample and yaml parsing to not raise any warnings
> - description for memory-region in yaml parsing
> - compatible string in yaml parsing for TCM
> v6:
> - remove coupling TCM nodes with remoteproc
> - remove mailbox as it is optional not needed
> v7:
> - change lockstep-mode to xlnx,cluster-mode
> v9:
> - show example IPC nodes and tcm bank nodes
> v11:
> - add property meta-memory-regions to illustrate link
> between r5 and TCM banks
> - update so no warnings from 'make dt_binding_check'
> v14:
> - concerns were raised about the new property meta-memory-regions.
> There is no clear direction so for the moment I kept it in the series
> - place IPC nodes in RAM in the reserved memory section
> v15:
> - change lockstep-mode prop as follows: if present, then RPU cluster is in
> lockstep mode. if not present, cluster is in split mode.
> v17:
> - remove compatible string from tcm bank nodes
> - fix style for bindings
> - add boolean type to lockstep mode in binding
> - add/update descriptions memory-region, meta-memory-regions,
> pnode-id, mbox* properties
> v18:
> - update example remoteproc zynqmp r5 compat string, remove version
> number
> - change property from memory-region to memory-regions
> ---
> .../xilinx,zynqmp-r5-remoteproc.yaml | 142 ++++++++++++++++++
> 1 file changed, 142 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/remoteproc/xilinx,zynqmp-r5-remoteproc.yaml
>
> diff --git a/Documentation/devicetree/bindings/remoteproc/xilinx,zynqmp-r5-remoteproc.yaml b/Documentation/devicetree/bindings/remoteproc/xilinx,zynqmp-r5-remoteproc.yaml
> new file mode 100644
> index 000000000000..c202dca3b6d0
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/remoteproc/xilinx,zynqmp-r5-remoteproc.yaml
> @@ -0,0 +1,142 @@
> +# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: "http://devicetree.org/schemas/remoteproc/xilinx,zynqmp-r5-remoteproc.yaml#";
> +$schema: "http://devicetree.org/meta-schemas/core.yaml#";
> +
> +title: Xilinx R5 remote processor controller bindings
> +
> +description:
> + This document defines the binding for the remoteproc component that loads and
> + boots firmwares on the Xilinx Zynqmp and Versal family chipset.
> +
> + Note that the Linux has global addressing view of the R5-related memory (TCM)
> + so the absolute address ranges are provided in TCM reg's.
> +
> +maintainers:
> + - Ed Mooring <ed.mooring@xxxxxxxxxx>
> + - Ben Levinsky <ben.levinsky@xxxxxxxxxx>
> +
> +properties:
> + compatible:
> + const: xlnx,zynqmp-r5-remoteproc
> +
> + lockstep-mode:
> + description:
> + If this property is present, then the configuration is lock-step.
> + Otherwise RPU is split.
> + type: boolean
> + maxItems: 1
> +
> + interrupts:
> + description:
> + Interrupt mapping for remoteproc IPI. It is required if the
> + user uses the remoteproc driver with the RPMsg kernel driver.
> + maxItems: 6
> +
> + memory-regions:
> + description:
> + collection of memory carveouts used for elf-loading and inter-processor

For each of the above the first line of the description had a capital letter
while this one (and the one below) don't.

> + communication. each carveout in this case should be in DDR, not

Again this is abnormal - please fix everywhere.

> + chip-specific memory. In Xilinx case, this is TCM, OCM, BRAM, etc.
> + $ref: /schemas/types.yaml#/definitions/phandle-array
> +
> + meta-memory-regions:
> + description:
> + collection of memories that are not present in the top level memory
> + nodes' mapping. For example, R5s' TCM banks. These banks are needed
> + for R5 firmware meta data such as the R5 firmware's heap and stack.
> + To be more precise, this is on-chip reserved SRAM regions, e.g. TCM,
> + BRAM, OCM, etc.
> + $ref: /schemas/types.yaml#/definitions/phandle-array
> +
> + pnode-id:
> + maxItems: 1
> + description:
> + power node id that is used to uniquely identify the node for Xilinx
> + Power Management. The value is then passed to Xilinx platform
> + manager for power on/off and access.
> + $ref: /schemas/types.yaml#/definitions/uint32
> +
> + mboxes:
> + description:
> + array of phandles that describe the rx and tx for xilinx zynqmp
> + mailbox driver. order of rx and tx is described by the mbox-names
> + property. This will be used for communication with remote
> + processor.
> + maxItems: 2
> +
> + mbox-names:
> + description:
> + array of strings that denote which item in the mboxes property array
> + are the rx and tx for xilinx zynqmp mailbox driver
> + maxItems: 2
> + $ref: /schemas/types.yaml#/definitions/string-array
> +
> +
> +examples:
> + - |
> + reserved-memory {
> + #address-cells = <1>;
> + #size-cells = <1>;
> + ranges;
> + elf_load: rproc@3ed000000 {
> + no-map;
> + reg = <0x3ed00000 0x40000>;
> + };
> +
> + rpu0vdev0vring0: rpu0vdev0vring0@3ed40000 {
> + no-map;
> + reg = <0x3ed40000 0x4000>;
> + };
> + rpu0vdev0vring1: rpu0vdev0vring1@3ed44000 {
> + no-map;
> + reg = <0x3ed44000 0x4000>;
> + };
> + rpu0vdev0buffer: rpu0vdev0buffer@3ed48000 {
> + no-map;
> + reg = <0x3ed48000 0x100000>;
> + };
> +
> + };
> +
> + /*
> + * Below nodes are required if using TCM to load R5 firmware
> + * if not, then either do not provide nodes are label as disabled in

s/are/or

> + * status property
> + */
> + tcm0a: tcm_0a@ffe00000 {
> + reg = <0xffe00000 0x10000>;
> + pnode-id = <0xf>;
> + no-map;
> + status = "okay";
> + phandle = <0x40>;
> + };
> + tcm0b: tcm_1a@ffe20000 {
> + reg = <0xffe20000 0x10000>;
> + pnode-id = <0x10>;
> + no-map;
> + status = "okay";
> + phandle = <0x41>;
> + };
> +
> + rpu {
> + compatible = "xlnx,zynqmp-r5-remoteproc";
> + #address-cells = <1>;
> + #size-cells = <1>;
> + ranges;
> + lockstep-mode;
> + r5_0 {
> + ranges;
> + #address-cells = <1>;
> + #size-cells = <1>;
> + memory-regions = <&elf_load>,
> + <&rpu0vdev0vring0>,
> + <&rpu0vdev0vring1>,
> + <&rpu0vdev0buffer>;
> + meta-memory-regions = <&tcm_0a>, <&tcm_0b>;
> + pnode-id = <0x7>;
> + };
> + };
> +
> +...
> --
> 2.17.1
>