Add device-tree binding documentation to represent
the Control Backbone (CBB) version 2.0 used in T234 SoC.
Signed-off-by: Sumit Gupta <[email protected]>
---
.../arm/tegra/nvidia,tegra234-cbb.yaml | 74 +++++++++++++++++++
1 file changed, 74 insertions(+)
create mode 100644 Documentation/devicetree/bindings/arm/tegra/nvidia,tegra234-cbb.yaml
diff --git a/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra234-cbb.yaml b/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra234-cbb.yaml
new file mode 100644
index 000000000000..7b1fe50ffbe0
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/tegra/nvidia,tegra234-cbb.yaml
@@ -0,0 +1,74 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: "http://devicetree.org/schemas/arm/tegra/nvidia,tegra234-cbb.yaml#"
+$schema: "http://devicetree.org/meta-schemas/core.yaml#"
+
+title: NVIDIA Tegra CBB 2.0 bindings
+
+maintainers:
+ - Sumit Gupta <[email protected]>
+
+description: |+
+ The Control Backbone (CBB) is comprised of the physical path from an
+ initiator to a target's register configuration space. CBB 2.0 consists
+ of multiple sub-blocks connected to each other to create a topology.
+ The Tegra234 SoC has different fabrics based on CBB 2.0 architecture
+ which include cluster fabrics BPMP, AON, PSC, SCE, RCE, DCE, FSI and
+ "CBB central fabric".
+
+ In CBB 2.0, each initiator which can issue transactions connects to a
+ Root Master Node (MN) before it connects to any other element of the
+ fabric. Each Root MN contains a Error Monitor (EM) which detects and
+ logs error. Interrupts from various EM blocks are collated by Error
+ Notifier (EN) which is per fabric and presents a single interrupt from
+ fabric to the SoC interrupt controller.
+
+ The driver handles errors from CBB due to illegal register accesses
+ and prints debug information about failed transaction on receiving
+ the interrupt from EN. Debug information includes Error Code, Error
+ Description, MasterID, Fabric, SlaveID, Address, Cache, Protection,
+ Security Group etc on receiving error notification.
+
+ If the Error Response Disable (ERD) is set/enabled for an initiator,
+ then SError or Data abort exception error response is masked and an
+ interrupt is used for reporting errors due to illegal accesses from
+ that initiator. The value returned on read failures is '0xFFFFFFFF'
+ for compatibility with PCIE.
+
+properties:
+ $nodename:
+ pattern: "^[a-z]+-fabric@[0-9a-f]+$"
+
+ compatible:
+ enum:
+ - nvidia,tegra234-aon-fabric
+ - nvidia,tegra234-bpmp-fabric
+ - nvidia,tegra234-cbb-fabric
+ - nvidia,tegra234-dce-fabric
+ - nvidia,tegra234-rce-fabric
+ - nvidia,tegra234-sce-fabric
+
+ reg:
+ maxItems: 1
+
+ interrupts:
+ items:
+ - description: secure interrupt from error notifier
+
+additionalProperties: false
+
+required:
+ - compatible
+ - reg
+ - interrupts
+
+examples:
+ - |
+ #include <dt-bindings/interrupt-controller/arm-gic.h>
+
+ cbb-fabric@1300000 {
+ compatible = "nvidia,tegra234-cbb-fabric";
+ reg = <0x13a00000 0x400000>;
+ interrupts = <GIC_SPI 231 IRQ_TYPE_LEVEL_HIGH>;
+ };
--
2.17.1
On Thu, 12 May 2022 01:46:48 +0530, Sumit Gupta wrote:
> Add device-tree binding documentation to represent
> the Control Backbone (CBB) version 2.0 used in T234 SoC.
>
> Signed-off-by: Sumit Gupta <[email protected]>
> ---
> .../arm/tegra/nvidia,tegra234-cbb.yaml | 74 +++++++++++++++++++
> 1 file changed, 74 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/arm/tegra/nvidia,tegra234-cbb.yaml
>
Reviewed-by: Rob Herring <[email protected]>