Re: [PATCH v6 1/6] dt-bindings: remoteproc: Add Xilinx RPU subsystem bindings

From: Tanmay Shah
Date: Wed Jun 01 2022 - 16:45:46 EST


Hi Rob,

Thanks for reviews. Please find my comments below:

On 6/1/22 11:42 AM, Rob Herring wrote:
On Tue, May 31, 2022 at 04:43:05PM -0700, Tanmay Shah wrote:
Xilinx ZynqMP platform has dual-core ARM Cortex R5 Realtime Processing
Unit(RPU) subsystem. This patch adds dt-bindings for RPU subsystem
(cluster).

Signed-off-by: Tanmay Shah <tanmay.shah@xxxxxxxxxx>
---

Changes in v6:
- Add maxItems to sram and memory-region property

Changes in v5:
- Add constraints of the possible values of xlnx,cluster-mode property
- fix description of power-domains property for r5 core
- Remove reg, address-cells and size-cells properties as it is not required
- Fix description of mboxes property
- Add description of each memory-region and remove old .txt binding link
reference in the description

Changes in v4:
- Add memory-region, mboxes and mbox-names properties in example

Changes in v3:
- None


.../bindings/remoteproc/xlnx,r5f-rproc.yaml | 129 ++++++++++++++++++
include/dt-bindings/power/xlnx-zynqmp-power.h | 6 +
2 files changed, 135 insertions(+)
create mode 100644 Documentation/devicetree/bindings/remoteproc/xlnx,r5f-rproc.yaml

diff --git a/Documentation/devicetree/bindings/remoteproc/xlnx,r5f-rproc.yaml b/Documentation/devicetree/bindings/remoteproc/xlnx,r5f-rproc.yaml
new file mode 100644
index 000000000000..cbff1c201a89
--- /dev/null
+++ b/Documentation/devicetree/bindings/remoteproc/xlnx,r5f-rproc.yaml
@@ -0,0 +1,129 @@
+# SPDX-License-Identifier: (GPL-2.0-only or BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/remoteproc/xlnx,r5f-rproc.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Xilinx R5F processor subsystem
+
+maintainers:
+ - Ben Levinsky <ben.levinsky@xxxxxxxxxx>
+ - Tanmay Shah <tanmay.shah@xxxxxxxxxx>
+
+description: |
+ The Xilinx platforms include a pair of Cortex-R5F processors (RPU) for
+ real-time processing based on the Cortex-R5F processor core from ARM.
+ The Cortex-R5F processor implements the Arm v7-R architecture and includes a
+ floating-point unit that implements the Arm VFPv3 instruction set.
+
+properties:
+ compatible:
+ const: xlnx,zynqmp-r5fss
+
+ xlnx,cluster-mode:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ enum: [0, 1, 2]
+ description: |
+ The RPU MPCore can operate in split mode(Dual-processor performance), Safety
+ lock-step mode(Both RPU cores execute the same code in lock-step,
+ clock-for-clock) or Single CPU mode (RPU core 0 can be held in reset while
+ core 1 runs normally). The processor does not support dynamic configuration.
+ Switching between modes is only permitted immediately after a processor reset.
+ If set to 1 then lockstep mode and if 0 then split mode.
+ If set to 2 then single CPU mode. When not defined, default will be lockstep mode.
+
+patternProperties:
+ "^r5f-[a-f0-9]+$":
+ type: object
+ description: |
+ The RPU is located in the Low Power Domain of the Processor Subsystem.
+ Each processor includes separate L1 instruction and data caches and
+ tightly coupled memories (TCM). System memory is cacheable, but the TCM
+ memory space is non-cacheable.
+
+ Each RPU contains one 64KB memory and two 32KB memories that
+ are accessed via the TCM A and B port interfaces, for a total of 128KB
+ per processor. In lock-step mode, the processor has access to 256KB of
+ TCM memory.
+
+ properties:
+ compatible:
+ const: xlnx,zynqmp-r5f
+
+ power-domains:
+ description: RPU core PM domain specifier
+ maxItems: 1
+
+ mboxes:
+ minItems: 1
+ items:
+ - description: mailbox channel to send data to RPU
+ - description: mailbox channel to receive data from RPU
+
+ mbox-names:
+ minItems: 1
+ items:
+ - const: tx
+ - const: rx
+
+ sram:
+ $ref: /schemas/types.yaml#/definitions/phandle-array
+ maxItems: 8
minItems: 1
maxItems: 8
items:
maxItems: 1

I have posted v7 which adds "minItems: 1".

However, I didn't get items: part. Is it required to have items: now?

Can I add items: part once TCM bindings are posted?

I understand that minItems and maxItems under sram property decides how many phandles sram can have.

However, maxItems: 1 under items: field what it describes?

Thanks.


+ description: |
+ phandles to one or more reserved on-chip SRAM regions. Other than TCM,
+ the RPU can execute instructions and access data from, the OCM memory,
+ the main DDR memory, and other system memories.
+
+ The regions should be defined as child nodes of the respective SRAM
+ node, and should be defined as per the generic bindings in,
+ Documentation/devicetree/bindings/sram/sram.yaml
+
+ memory-region:
+ description: |
+ List of phandles to the reserved memory regions associated with the
+ remoteproc device. This is variable and describes the memories shared with
+ the remote processor (e.g. remoteproc firmware and carveouts, rpmsg
+ vrings, ...). This reserved memory region will be allocated on DDR memory.
+ minItems: 1
+ maxItems: 8
+ items:
+ - description: region used for RPU firmware image section
+ - description: vdev buffer
+ - description: vring0
+ - description: vring1
+ additionalItems: true
+
+ required:
+ - compatible
+ - power-domains
+
+ unevaluatedProperties: false
+
+required:
+ - compatible
+
+additionalProperties: false
+
+examples:
+ - |
+ r5fss: r5fss {
+ compatible = "xlnx,zynqmp-r5fss";
+ xlnx,cluster-mode = <1>;
+
+ r5f-0 {
+ compatible = "xlnx,zynqmp-r5f";
+ power-domains = <&zynqmp_firmware 0x7>;
+ memory-region = <&rproc_0_fw_image>, <&rpu0vdev0buffer>, <&rpu0vdev0vring0>, <&rpu0vdev0vring1>;
+ mboxes = <&ipi_mailbox_rpu0 0>, <&ipi_mailbox_rpu0 1>;
+ mbox-names = "tx", "rx";
+ };
+
+ r5f-1 {
+ compatible = "xlnx,zynqmp-r5f";
+ power-domains = <&zynqmp_firmware 0x8>;
+ memory-region = <&rproc_1_fw_image>, <&rpu1vdev0buffer>, <&rpu1vdev0vring0>, <&rpu1vdev0vring1>;
+ mboxes = <&ipi_mailbox_rpu1 0>, <&ipi_mailbox_rpu1 1>;
+ mbox-names = "tx", "rx";
+ };
+ };
+...
diff --git a/include/dt-bindings/power/xlnx-zynqmp-power.h b/include/dt-bindings/power/xlnx-zynqmp-power.h
index 0d9a412fd5e0..618024cbb20d 100644
--- a/include/dt-bindings/power/xlnx-zynqmp-power.h
+++ b/include/dt-bindings/power/xlnx-zynqmp-power.h
@@ -6,6 +6,12 @@
#ifndef _DT_BINDINGS_ZYNQMP_POWER_H
#define _DT_BINDINGS_ZYNQMP_POWER_H
+#define PD_RPU_0 7
+#define PD_RPU_1 8
+#define PD_R5_0_ATCM 15
+#define PD_R5_0_BTCM 16
+#define PD_R5_1_ATCM 17
+#define PD_R5_1_BTCM 18
#define PD_USB_0 22
#define PD_USB_1 23
#define PD_TTC_0 24
--
2.25.1