Re: [PATCH v2 2/2] dt-bindings: PCI: Convert PCIe Host/Endpoint in Cadence platform to DT schema

Rob,

On 24/02/20 8:56 pm, Rob Herring wrote:

On Mon, Feb 24, 2020 at 4:14 AM Kishon Vijay Abraham I [off-list ref] wrote:

quoted

Hi Rob,

On 20/02/20 2:02 am, Rob Herring wrote:

quoted

On Mon, Feb 17, 2020 at 04:45:19PM +0530, Kishon Vijay Abraham I wrote:

quoted

Include Cadence core DT schema and define the Cadence platform DT schema
for both Host and Endpoint mode. Note: The Cadence core DT schema could
be included for other platforms using Cadence PCIe core.

Signed-off-by: Kishon Vijay Abraham I <redacted>
---
 .../bindings/pci/cdns,cdns-pcie-ep.txt        | 27 -------
 .../bindings/pci/cdns,cdns-pcie-ep.yaml       | 48 ++++++++++++
 .../bindings/pci/cdns,cdns-pcie-host.txt      | 66 ----------------
 .../bindings/pci/cdns,cdns-pcie-host.yaml     | 76 +++++++++++++++++++
 MAINTAINERS                                   |  2 +-
 5 files changed, 125 insertions(+), 94 deletions(-)
 delete mode 100644 Documentation/devicetree/bindings/pci/cdns,cdns-pcie-ep.txt
 create mode 100644 Documentation/devicetree/bindings/pci/cdns,cdns-pcie-ep.yaml
 delete mode 100644 Documentation/devicetree/bindings/pci/cdns,cdns-pcie-host.txt
 create mode 100644 Documentation/devicetree/bindings/pci/cdns,cdns-pcie-host.yaml

quoted

diff --git a/Documentation/devicetree/bindings/pci/cdns,cdns-pcie-host.yaml b/Documentation/devicetree/bindings/pci/cdns,cdns-pcie-host.yaml
new file mode 100644
index 000000000000..2f605297f862
--- /dev/null
+++ b/Documentation/devicetree/bindings/pci/cdns,cdns-pcie-host.yaml

@@ -0,0 +1,76 @@
+# SPDX-License-Identifier: GPL-2.0-only
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/pci/cdns,cdns-pcie-host.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Cadence PCIe host controller
+
+maintainers:
+  - Tom Joseph <tjoseph@cadence.com>
+
+allOf:
+  - $ref: /schemas/pci/pci-bus.yaml#
+  - $ref: "cdns-pcie-host.yaml#"
+
+properties:
+  compatible:
+    const: cdns,cdns-pcie-host
+
+  reg:
+    maxItems: 3
+
+  reg-names:
+    items:
+      - const: reg
+      - const: cfg
+      - const: mem
+
+  msi-parent: true
+
+required:
+  - reg
+  - reg-names
+
+examples:
+  - |
+    bus {
+        #address-cells = <2>;
+        #size-cells = <2>;
+
+        pcie@fb000000 {
+            compatible = "cdns,cdns-pcie-host";
+            device_type = "pci";
+            #address-cells = <3>;
+            #size-cells = <2>;
+            bus-range = <0x0 0xff>;
+            linux,pci-domain = <0>;
+            cdns,max-outbound-regions = <16>;
+            cdns,no-bar-match-nbits = <32>;

quoted

+            vendor-id = /bits/ 16 <0x17cd>;
+            device-id = /bits/ 16 <0x0200>;

Please make these 32-bit as that is what the spec says.

Can you clarify this is mentioned in which spec? PCI spec has both of
these 16 bits and I checked the PCI binding doc but couldn't spot the
size of these fields.

[1] -> https://www.devicetree.org/open-firmware/bindings/pci/pci2_1.pdf

Section 4.1.2.1. The key point is the type is 'encode-int' which means
32-bit. Keep in mind, that 16-bits was not a defined type when this
spec was written. We added that for FDT.

Also, look at other instances of reading 'vendor-id' in the kernel.

Thanks for clarifying.

Regards
Kishon