Re: [PATCH net-next v2 2/3] dt-bindings: net: add T-HEAD dwmac support

On Mon, Aug 28, 2023 at 04:13:00PM +0300, Serge Semin wrote:

On Sun, Aug 27, 2023 at 05:17:09PM +0800, Jisheng Zhang wrote:

quoted

Add documentation to describe T-HEAD dwmac.

Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
---
 .../devicetree/bindings/net/snps,dwmac.yaml   |  1 +
 .../devicetree/bindings/net/thead,dwmac.yaml  | 77 +++++++++++++++++++
 2 files changed, 78 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/net/thead,dwmac.yaml

diff --git a/Documentation/devicetree/bindings/net/snps,dwmac.yaml b/Documentation/devicetree/bindings/net/snps,dwmac.yaml
index b196c5de2061..73821f86a609 100644
--- a/Documentation/devicetree/bindings/net/snps,dwmac.yaml
+++ b/Documentation/devicetree/bindings/net/snps,dwmac.yaml

@@ -96,6 +96,7 @@ properties:
         - snps,dwxgmac
         - snps,dwxgmac-2.10
         - starfive,jh7110-dwmac
+        - thead,th1520-dwmac
 
   reg:
     minItems: 1

diff --git a/Documentation/devicetree/bindings/net/thead,dwmac.yaml b/Documentation/devicetree/bindings/net/thead,dwmac.yaml
new file mode 100644
index 000000000000..bf8ec8ca2753
--- /dev/null

quoted

+++ b/Documentation/devicetree/bindings/net/thead,dwmac.yaml

see further regarding using dwmac in the names here.

quoted

@@ -0,0 +1,77 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/net/thead,dwmac.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+

quoted

+title: T-HEAD DWMAC Ethernet controller

Additionally would be nice to have a brief controller "description:"
having the next info: the SoCs the controllers can be found on, the DW
(G)MAC IP-core version the ethernet controller is based on and some
data about the synthesize parameters: SMA (MDIO-bus), Tx/Rx COE, DMA
FIFOs size, perfect and hash MAC-filters size, L3L4 frame filters
availability, VLAN hash filter, SA/VLAN-tag insertion, ARP offload
engine, PHY interfaces (MII, RMII, RGMII, etc), EEE support, IEEE
1588(-2008) Timestamping support, PMT and Wake-up frame support, MAC
Management counters (MMC). In addition to that for DW QoS
ETH/XGMAC/XLGMAC the next info would be useful: number of MTL Queues
and DMA channels, MTL queues capabilities (QoS-related), TSO
availability, SPO availability.

Note DMA FIFO sizes can be also constrained in the properties
"rx-fifo-depth" and "tx-fifo-depth"; perfect and hash MAC-filter sizes -
in "snps,perfect-filter-entries" and "snps,multicast-filter-bins".

Hi Serge,

Thank you for your code review. I have different views here: If we
only support the gmac controller in one specific SoC, these detailed
information is nice to have, but what about if the driver/dt-binding
supports the gmac controller in different SoCs? These detailed
information will be outdated.

what's more, I think the purpose of dt-binding is different from
the one of documentation.

So I prefer to put these GMAC IP related detailed information into
the SoC's dtsi commit msg rather than polluting the dt-binding.

quoted

+
+maintainers:
+  - Jisheng Zhang [off-list ref]
+
+select:
+  properties:
+    compatible:
+      contains:
+        enum:

quoted

+          - thead,th1520-dwmac

Referring to the DW IP-core in the compatible string isn't very
much useful especially seeing you have a generic fallback compatible.
Name like "thead,th1520-gmac" looks more informative indicating its
speed capability.

This is just to follow the common style as those dwmac-* does.
I'm not sure which is better, but personally, I'd like to keep current
common style.