Re: [PATCH v4 1/8] dt-bindings: Add Cavium Octeon Common Ethernet Interface.

From: David Daney
Date: Tue Nov 28 2017 - 21:54:24 EST


On 11/28/2017 06:01 PM, Andrew Lunn wrote:
On Tue, Nov 28, 2017 at 04:55:33PM -0800, David Daney wrote:
From: Carlos Munoz <cmunoz@xxxxxxxxxx>

Add bindings for Common Ethernet Interface (BGX) block.

Acked-by: Rob Herring <robh@xxxxxxxxxx>
Signed-off-by: Carlos Munoz <cmunoz@xxxxxxxxxx>
Signed-off-by: Steven J. Hill <Steven.Hill@xxxxxxxxxx>
Signed-off-by: David Daney <david.daney@xxxxxxxxxx>
---
.../devicetree/bindings/net/cavium-bgx.txt | 61 ++++++++++++++++++++++
1 file changed, 61 insertions(+)
create mode 100644 Documentation/devicetree/bindings/net/cavium-bgx.txt

diff --git a/Documentation/devicetree/bindings/net/cavium-bgx.txt b/Documentation/devicetree/bindings/net/cavium-bgx.txt
new file mode 100644
index 000000000000..830c5f08dddd
--- /dev/null
+++ b/Documentation/devicetree/bindings/net/cavium-bgx.txt
@@ -0,0 +1,61 @@
+* Common Ethernet Interface (BGX) block
+
+Properties:
+
+- compatible: "cavium,octeon-7890-bgx": Compatibility with all cn7xxx SOCs.
+
+- reg: The base address of the BGX block.
+
+- #address-cells: Must be <1>.
+
+- #size-cells: Must be <0>. BGX addresses have no size component.
+
+A BGX block has several children, each representing an Ethernet
+interface.
+
+
+* Ethernet Interface (BGX port) connects to PKI/PKO
+
+Properties:
+
+- compatible: "cavium,octeon-7890-bgx-port": Compatibility with all
+ cn7xxx SOCs.
+
+ "cavium,octeon-7360-xcv": Compatibility with cn73xx SOCs
+ for RGMII.
+
+- reg: The index of the interface within the BGX block.
+
+Optional properties:
+
+- local-mac-address: Mac address for the interface.
+
+- phy-handle: phandle to the phy node connected to the interface.
+
+- phy-mode: described in ethernet.txt.
+
+- fixed-link: described in fixed-link.txt.
+
+Example:
+
+ ethernet-mac-nexus@11800e0000000 {
+ compatible = "cavium,octeon-7890-bgx";
+ reg = <0x00011800 0xe0000000 0x00000000 0x01000000>;

Hi David

In the probe function we have:

+ reg = of_get_property(pdev->dev.of_node, "reg", NULL);
+ addr = of_translate_address(pdev->dev.of_node, reg);
+ interface = (addr >> 24) & 0xf;
+ numa_node = (addr >> 36) & 0x7;

Is this documented somewhere?

In the Hardware Reference Manual for the chips.


The numa_node is particularly
interesting. MMIO changes depends on what node this is in the cluster?

Yes. Bits 38..36 of MMIO addresses indicate which NUMA node the corresponding hardware device resides on. Some operations can only be performed by a CPU on the same NUMA node as the device (RX or TX-complete interrupts for example) Other operations can cross CPU nodes (TX packet submission for example)



Andrew