Re: [PATCH v3 1/2] dt-bindings: PCI: intel: Add YAML schemas for the PCIe RC controller

From: Dilip Kota
Date: Wed Sep 18 2019 - 02:56:44 EST



On 9/18/2019 2:40 AM, Rob Herring wrote:
On Wed, Sep 04, 2019 at 06:10:30PM +0800, Dilip Kota wrote:
The Intel PCIe RC controller is Synopsys Designware
based PCIe core. Add YAML schemas for PCIe in RC mode
present in Intel Universal Gateway soc.

Signed-off-by: Dilip Kota <eswara.kota@xxxxxxxxxxxxxxx>
---
changes on v3:
Add the appropriate License-Identifier
Rename intel,rst-interval to 'reset-assert-us'
Add additionalProperties: false
Rename phy-names to 'pciephy'
Remove the dtsi node split of SoC and board in the example
Add #interrupt-cells = <1>; or else interrupt parsing will fail
Name yaml file with compatible name

.../devicetree/bindings/pci/intel,lgm-pcie.yaml | 137 +++++++++++++++++++++
1 file changed, 137 insertions(+)
create mode 100644 Documentation/devicetree/bindings/pci/intel,lgm-pcie.yaml

diff --git a/Documentation/devicetree/bindings/pci/intel,lgm-pcie.yaml b/Documentation/devicetree/bindings/pci/intel,lgm-pcie.yaml
new file mode 100644
index 000000000000..5e5cc7fd66cd
--- /dev/null
+++ b/Documentation/devicetree/bindings/pci/intel,lgm-pcie.yaml
@@ -0,0 +1,137 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/pci/intel-pcie.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Intel AXI bus based PCI express root complex
+
+maintainers:
+ - Dilip Kota <eswara.kota@xxxxxxxxxxxxxxx>
+
+properties:
+ compatible:
+ const: intel,lgm-pcie
+
+ device_type:
+ const: pci
+
+ "#address-cells":
+ const: 3
+
+ "#size-cells":
+ const: 2
These all belong in a common schema.

+
+ reg:
+ items:
+ - description: Controller control and status registers.
+ - description: PCIe configuration registers.
+ - description: Controller application registers.
+
+ reg-names:
+ items:
+ - const: dbi
+ - const: config
+ - const: app
+
+ ranges:
+ description: Ranges for the PCI memory and I/O regions.
And this.

+
+ resets:
+ maxItems: 1
+
+ clocks:
+ description: PCIe registers interface clock.
+
+ phys:
+ maxItems: 1
+
+ phy-names:
+ const: pciephy
+
+ reset-gpios:
+ maxItems: 1
+
+ num-lanes:
+ description: Number of lanes to use for this port.
+
+ linux,pci-domain:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description: PCI domain ID.
These 2 also should be common.

+
+ interrupts:
+ description: PCIe core integrated miscellaneous interrupt.
How many? No need for description if there's only 1.

+
+ '#interrupt-cells':
+ const: 1
+
+ interrupt-map-mask:
+ description: Standard PCI IRQ mapping properties.
+
+ interrupt-map:
+ description: Standard PCI IRQ mapping properties.
+
+ max-link-speed:
+ description: Specify PCI Gen for link capability.
+
+ bus-range:
+ description: Range of bus numbers associated with this controller.
All common.
You mean to remove all the common schema entries description!.
In most of the Documention/devicetree/binding/pci documents all the common entries are described so I followed the same.

+
+ reset-assert-ms:
+ description: |
+ Device reset interval in ms.
+ Some devices need an interval upto 500ms. By default it is 100ms.
This is a property of a device, so it belongs in a device node. How
would you deal with this without DT?
This property is for the PCIe RC to keep a delay before notifying the reset to the device.
If this entry is not present, PCIe driver will set a default value of 100ms.

+
+required:
+ - compatible
+ - device_type
+ - reg
+ - reg-names
+ - ranges
+ - resets
+ - clocks
+ - phys
+ - phy-names
+ - reset-gpios
+ - num-lanes
+ - linux,pci-domain
+ - interrupts
+ - interrupt-map
+ - interrupt-map-mask
+
+additionalProperties: false
+
+examples:
+ - |
+ pcie10:pcie@d0e00000 {
+ compatible = "intel,lgm-pcie";
+ device_type = "pci";
+ #address-cells = <3>;
+ #size-cells = <2>;
+ reg = <
+ 0xd0e00000 0x1000
+ 0xd2000000 0x800000
+ 0xd0a41000 0x1000
+ >;
+ reg-names = "dbi", "config", "app";
+ linux,pci-domain = <0>;
+ max-link-speed = <4>;
+ bus-range = <0x00 0x08>;
+ interrupt-parent = <&ioapic1>;
+ interrupts = <67 1>;
+ #interrupt-cells = <1>;
+ interrupt-map-mask = <0 0 0 0x7>;
+ interrupt-map = <0 0 0 1 &ioapic1 27 1>,
+ <0 0 0 2 &ioapic1 28 1>,
+ <0 0 0 3 &ioapic1 29 1>,
+ <0 0 0 4 &ioapic1 30 1>;
+ ranges = <0x02000000 0 0xd4000000 0xd4000000 0 0x04000000>;
+ resets = <&rcu0 0x50 0>;
+ clocks = <&cgu0 LGM_GCLK_PCIE10>;
+ phys = <&cb0phy0>;
+ phy-names = "pciephy";
+ status = "okay";
+ reset-assert-ms = <500>;
+ reset-gpios = <&gpio0 3 GPIO_ACTIVE_LOW>;
+ num-lanes = <2>;
+ };
--
2.11.0