[PATCH v3] dt-bindings: remoteproc: add Tightly Coupled Memory (TCM) bindings

[Radhey Shyam Pandey <radhey.shyam.pandey@amd.com>]

Introduce bindings for TCM memory address space on AMD-xilinx Zynq
UltraScale+ platform. It will help in defining TCM in device-tree
and make it's access platform agnostic and data-driven.

Tightly-coupled memories(TCMs) are low-latency memory that provides
predictable instruction execution and predictable data load/store
timing. Each Cortex-R5F processor contains two 64-bit wide 64 KB memory
banks on the ATCM and BTCM ports, for a total of 128 KB of memory.

The TCM resources(reg, reg-names and power-domain) are documented for
each TCM in the R5 node. The reg and reg-names are made as required
properties as we don't want to hardcode TCM addresses for future
platforms and for zu+ legacy implementation will ensure that the
old dts w/o reg/reg-names works and stable ABI is maintained.

It also extends the examples for TCM split and lockstep modes.

Signed-off-by: Radhey Shyam Pandey <radhey.shyam.pandey@amd.com>
---
Changes for v3:
- Modified commit description to document that reg/reg-names are
  made as required properties and add justification for it.
- Drop 'Address and Size of' in reg items description.
- Modified commit description to remove driver reference.

Changes for v2:
- Add ranges property to r5fss cluster node.
- Use regex "^r5f(@[0-9a-f]+|-[a-f0-9]+)$".
- Drop address/size-cells and ranges from r5f core node.
- Mention "reg" and "reg names" as r5f core node required properties.
- Mention address/size-cells and ranges as r5fss required node
  properties.
- Modify commit description to remove ranges from R5 node.
- Rename r5f node labels(r5f_0 -> r5f_0_split/lockstep and
  r5f_1->r5f_1_split/lockstep)

The inspiration for integrating TCM nodes in R5 nodes is taken from
"5ee79c2ed5bd dt-bindings: remoteproc: Add bindings for R5F subsystem
on TI K3 SoCs".Once the binding is reviewed/accepted will send out
driver changes in follow-up series.
---
 .../bindings/remoteproc/xlnx,zynqmp-r5fss.yaml     | 90 ++++++++++++++++++++--
 1 file changed, 83 insertions(+), 7 deletions(-)

diff --git a/Documentation/devicetree/bindings/remoteproc/xlnx,zynqmp-r5fss.yaml b/Documentation/devicetree/bindings/remoteproc/xlnx,zynqmp-r5fss.yaml
index 9f677367dd9f..43089b0e8a39 100644
--- a/Documentation/devicetree/bindings/remoteproc/xlnx,zynqmp-r5fss.yaml
+++ b/Documentation/devicetree/bindings/remoteproc/xlnx,zynqmp-r5fss.yaml
@@ -20,6 +20,17 @@ properties:
   compatible:
     const: xlnx,zynqmp-r5fss
 
+  "#address-cells":
+    const: 1
+
+  "#size-cells":
+    const: 1
+
+  ranges:
+    description: |
+      Standard ranges definition providing address translations for
+      local R5F TCM address spaces to bus addresses.
+
   xlnx,cluster-mode:
     $ref: /schemas/types.yaml#/definitions/uint32
     enum: [0, 1, 2]
@@ -37,7 +48,7 @@ properties:
       2: single cpu mode
 
 patternProperties:
-  "^r5f-[a-f0-9]+$":
+  "^r5f@[0-9a-f]+$":
     type: object
     description: |
       The RPU is located in the Low Power Domain of the Processor Subsystem.
@@ -54,8 +65,19 @@ patternProperties:
       compatible:
         const: xlnx,zynqmp-r5f
 
+      reg:
+        items:
+          - description: ATCM internal memory region
+          - description: BTCM internal memory region
+
+      reg-names:
+        items:
+          - const: atcm
+          - const: btcm
+
       power-domains:
-        maxItems: 1
+        minItems: 1
+        maxItems: 3
 
       mboxes:
         minItems: 1
@@ -102,31 +124,85 @@ patternProperties:
     required:
       - compatible
       - power-domains
+      - reg
+      - reg-names
 
     unevaluatedProperties: false
 
 required:
   - compatible
+  - "#address-cells"
+  - "#size-cells"
+  - ranges
 
 additionalProperties: false
 
 examples:
   - |
-    remoteproc {
+    #include <dt-bindings/power/xlnx-zynqmp-power.h>
+
+    //Split mode configuration
+    remoteproc@ffe00000 {
+        compatible = "xlnx,zynqmp-r5fss";
+        xlnx,cluster-mode = <0>;
+
+        #address-cells = <1>;
+        #size-cells = <1>;
+        ranges = <0x0 0xffe00000 0x10000>, <0x20000 0xffe20000 0x10000>,
+                 <0x0 0xffe90000 0x10000>, <0x20000 0xffeb0000 0x10000>;
+
+        r5f_0_split: r5f@ffe00000 {
+            compatible = "xlnx,zynqmp-r5f";
+            reg = <0xffe00000 0x10000>, <0xffe20000 0x10000>;
+            reg-names = "atcm", "btcm";
+            power-domains = <&zynqmp_firmware PD_RPU_0>,
+                            <&zynqmp_firmware PD_R5_0_ATCM>,
+                            <&zynqmp_firmware PD_R5_0_BTCM>;
+            memory-region = <&rproc_0_fw_image>, <&rpu0vdev0buffer>, <&rpu0vdev0vring0>, <&rpu0vdev0vring1>;
+            mboxes = <&ipi_mailbox_rpu0 0>, <&ipi_mailbox_rpu0 1>;
+            mbox-names = "tx", "rx";
+        };
+
+        r5f_1_split: r5f@ffe90000 {
+            compatible = "xlnx,zynqmp-r5f";
+            reg = <0xffe90000 0x10000>, <0xffeb0000 0x10000>;
+            reg-names = "atcm", "btcm";
+            power-domains = <&zynqmp_firmware PD_RPU_1>,
+                            <&zynqmp_firmware PD_R5_1_ATCM>,
+                            <&zynqmp_firmware PD_R5_1_BTCM>;
+            memory-region = <&rproc_1_fw_image>, <&rpu1vdev0buffer>, <&rpu1vdev0vring0>, <&rpu1vdev0vring1>;
+            mboxes = <&ipi_mailbox_rpu1 0>, <&ipi_mailbox_rpu1 1>;
+            mbox-names = "tx", "rx";
+        };
+    };
+
+  - |
+    //Lockstep configuration
+    remoteproc@ffe00000 {
         compatible = "xlnx,zynqmp-r5fss";
         xlnx,cluster-mode = <1>;
 
-        r5f-0 {
+        #address-cells = <1>;
+        #size-cells = <1>;
+        ranges = <0x0 0xffe00000 0x20000>, <0x20000 0xffe20000 0x20000>;
+
+        r5f_0_lockstep: r5f@ffe00000 {
             compatible = "xlnx,zynqmp-r5f";
-            power-domains = <&zynqmp_firmware 0x7>;
+            reg = <0xffe00000 0x20000>, <0xffe20000 0x20000>;
+            reg-names = "atcm", "btcm";
+            power-domains = <&zynqmp_firmware PD_RPU_0>,
+                            <&zynqmp_firmware PD_R5_0_ATCM>,
+                            <&zynqmp_firmware PD_R5_0_BTCM>;
             memory-region = <&rproc_0_fw_image>, <&rpu0vdev0buffer>, <&rpu0vdev0vring0>, <&rpu0vdev0vring1>;
             mboxes = <&ipi_mailbox_rpu0 0>, <&ipi_mailbox_rpu0 1>;
             mbox-names = "tx", "rx";
         };
 
-        r5f-1 {
+        r5f_1_lockstep: r5f@ffe90000 {
             compatible = "xlnx,zynqmp-r5f";
-            power-domains = <&zynqmp_firmware 0x8>;
+            reg = <0xffe90000 0x10000>, <0xffeb0000 0x10000>;
+            reg-names = "atcm", "btcm";
+            power-domains = <&zynqmp_firmware PD_RPU_1>;
             memory-region = <&rproc_1_fw_image>, <&rpu1vdev0buffer>, <&rpu1vdev0vring0>, <&rpu1vdev0vring1>;
             mboxes = <&ipi_mailbox_rpu1 0>, <&ipi_mailbox_rpu1 1>;
             mbox-names = "tx", "rx";
-- 
2.1.1