[v4,03/10] dt-bindings: pci: Add common schema for devices accessible through PCI BARs

Commit Message

Andrea della Porta Nov. 24, 2024, 10:51 a.m. UTC

Common YAML schema for devices that exports internal peripherals through
PCI BARs. The BARs are exposed as simple-buses through which the
peripherals can be accessed.

This is not intended to be used as a standalone binding, but should be
included by device specific bindings.

Signed-off-by: Andrea della Porta <[e-mail]>
---
 .../devicetree/bindings/pci/pci-ep-bus.yaml   | 58 +++++++++++++++++++
 MAINTAINERS                                   |  1 +
 2 files changed, 59 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/pci/pci-ep-bus.yaml

Patch

diff --git a/Documentation/devicetree/bindings/pci/pci-ep-bus.yaml b/Documentation/devicetree/bindings/pci/pci-ep-bus.yaml
new file mode 100644
index 000000000000..33479a5b40c6
--- /dev/null
+++ b/Documentation/devicetree/bindings/pci/pci-ep-bus.yaml
@@ -0,0 +1,58 @@ 
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/pci/pci-ep-bus.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Common Properties for PCI MFD EP with Peripherals Addressable from BARs
+
+maintainers:
+  - Andrea della Porta  <[e-mail]>
+
+description:
+  Define a generic node representing a PCI endpoint which contains several sub-
+  peripherals. The peripherals can be accessed through one or more BARs.
+  This common schema is intended to be referenced from device tree bindings, and
+  does not represent a device tree binding by itself.
+
+properties:
+  '#address-cells':
+    const: 3
+
+  '#size-cells':
+    const: 2
+
+  ranges:
+    minItems: 1
+    maxItems: 6
+    items:
+      maxItems: 8
+      additionalItems: true
+      items:
+        - maximum: 5  # The BAR number
+        - const: 0
+        - const: 0
+
+patternProperties:
+  '^pci-ep-bus@[0-5]$':
+    type: object
+    description:
+      One node for each BAR used by peripherals contained in the PCI endpoint.
+      Each node represent a bus on which peripherals are connected.
+      This allows for some segmentation, e.g. one peripheral is accessible
+      through BAR0 and another through BAR1, and you don't want the two
+      peripherals to be able to act on the other BAR. Alternatively, when
+      different peripherals need to share BARs, you can define only one node
+      and use 'ranges' property to map all the used BARs.
+
+    additionalProperties: true
+
+    properties:
+      compatible:
+        const: simple-bus
+
+    required:
+      - compatible
+
+additionalProperties: true
+...
diff --git a/MAINTAINERS b/MAINTAINERS
index c55d12550246..ccf123b805c8 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -19384,6 +19384,7 @@  RASPBERRY PI RP1 PCI DRIVER
 M:	Andrea della Porta <[e-mail]>
 S:	Maintained
 F:	Documentation/devicetree/bindings/clock/raspberrypi,rp1-clocks.yaml
+F:	Documentation/devicetree/bindings/pci/pci-ep-bus.yaml
 F:	Documentation/devicetree/bindings/pinctrl/raspberrypi,rp1-gpio.yaml
 F:	include/dt-bindings/clock/rp1.h
 F:	include/dt-bindings/misc/rp1.h