[PATCH net-next v2 0/2] Add DAPU Telecom DAP8211R(I) Gigabit Ethernet PHY driver

From: Artem Shimko

Date: Thu Jul 16 2026 - 07:42:31 EST

Hello,

This series adds support for the DAPU Telecom DAP8211R(I) Gigabit
Ethernet PHY, commonly used in enterprise and industrial networking
applications. The PHY supports 10/100/1000 Mbps operation with RGMII
interface and includes features such as IEEE 802.3az Energy Efficient
Ethernet, IEEE 1588 SyncE, and an internal packet generator for
diagnostics.

The driver implements extended register access via indirect addressing
(registers 0x1E/0x1F) and provides comprehensive device tree support
for RGMII delay configuration. The rx-internal-delay-ps and
tx-internal-delay-ps properties allow precise tuning of clock delays
in 150 ps steps from 0 to 2250 ps. The optional dapu,tx-inverted-clk
flag enables 180-degree TX clock phase shift for boards where signal
integrity or MAC requirements necessitate clock inversion.

This PHY is used on the NDA platform with 1G Ethernet tile and has
been tested on that hardware with successful link establishment and
RGMII delay tuning.

Due to the specific PCB layout of the platform and FPGA configuration,
the default RGMII timing configuration was insufficient, causing packet
loss during normal operation. Tuning the TX/RX line delays and enabling
clock inversion restored proper signal timing, resulting in zero packet
loss and stable link performance.

$ make dt_binding_check DT_SCHEMA_FILES=dapu,dap8211r.yaml
SCHEMA Documentation/devicetree/bindings/processed-schema.json
CHKDT ./Documentation/devicetree/bindings
LINT ./Documentation/devicetree/bindings
STYLE ./Documentation/devicetree/bindings
DTEX Documentation/devicetree/bindings/net/dapu,dap8211r.example.dts
DTC [C] Documentation/devicetree/bindings/net/dapu,dap8211r.example.dtb

grep -i "dap8211r" Documentation/devicetree/bindings/processed-schema.json
chema.json
"http://devicetree.org/schemas/net/dapu,dap8211r.yaml": {
"$filename": ".../devicetree/bindings/net/dapu,dap8211r.yaml",
"$id": "http://devicetree.org/schemas/net/dapu,dap8211r.yaml#";,
"title": "DAPU Telecom DAP8211R(I) Gigabit Ethernet PHY",

Working with xgmac.

Board side:

$ arping -I eth0 192.168.5.100
ARPING 192.168.5.1 from 192.168.5.100 eth0
Unicast reply from 192.168.5.1 [board.mac.addr] 8.543ms
Unicast reply from 192.168.5.1 [board.mac.addr] 3.295ms
Unicast reply from 192.168.5.1 [board.mac.addr] 4.301ms
Unicast reply from 192.168.5.1 [board.mac.addr] 4.096ms
Unicast reply from 192.168.5.1 [board.mac.addr] 2.872ms
...

$ Unfortunately, there is a dependence on the axibus speed here
$ iperf3 -c 192.168.5.1
Connecting to host 192.168.5.1, port 5201
[ 5] local 192.168.5.100 port 58936 connected to 192.168.5.1 port 5201
[ ID] Interval Transfer Bitrate Retr Cwnd
[ 5] 0.00-1.00 sec 7.88 MBytes 65.8 Mbits/sec 0 150 KBytes
[ 5] 1.00-2.00 sec 8.50 MBytes 71.4 Mbits/sec 0 165 KBytes
[ 5] 2.00-3.00 sec 8.25 MBytes 69.2 Mbits/sec 0 165 KBytes
[ 5] 3.00-4.01 sec 8.50 MBytes 71.1 Mbits/sec 0 165 KBytes
[ 5] 4.01-5.00 sec 8.38 MBytes 70.3 Mbits/sec 0 165 KBytes
[ 5] 5.00-6.00 sec 8.50 MBytes 71.5 Mbits/sec 0 165 KBytes
[ 5] 6.00-7.01 sec 8.62 MBytes 72.0 Mbits/sec 0 174 KBytes
[ 5] 7.01-8.00 sec 8.62 MBytes 72.8 Mbits/sec 0 174 KBytes
[ 5] 8.00-9.00 sec 8.62 MBytes 72.2 Mbits/sec 0 174 KBytes
[ 5] 9.00-10.04 sec 8.62 MBytes 69.9 Mbits/sec 0 174 KBytes
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval Transfer Bitrate Retr
[ 5] 0.00-10.04 sec 84.6 MBytes 70.7 Mbits/sec 0 sender
[ 5] 0.00-10.12 sec 84.8 MBytes 70.3 Mbits/sec receiveriperf Done.

$ ethtool -t eth0
...
The test extra info:
1. MAC Loopback 0
2. MAC Loopback (diff. queues) 0
3. PHY Loopback 0
...

ELP side:
...
17:29:11.974973 ARP, Reply ELP is-at elp.mac.addr(oui Unknown), length 28
17:29:12.975199 ARP, Request who-has ELP tell 192.168.5.100, length 46
17:29:12.975217 ARP, Reply ELP is-at elp.mac.addr(oui Unknown), length 28
17:29:13.975022 ARP, Request who-has ELP tell 192.168.5.100, length 46
17:29:13.975035 ARP, Reply ELP is-at elp.mac.addr(oui Unknown), length 28
17:29:14.974837 ARP, Request who-has ELP tell 192.168.5.100, length 46
17:29:14.974849 ARP, Reply ELP is-at elp.mac.addr(oui Unknown), length 28
17:29:15.975026 ARP, Request who-has ELP tell 192.168.5.100, length 46
...

Accepted connection from 192.168.5.100, port 58932
[ 5] local 192.168.5.1 port 5201 connected to 192.168.5.100 port 58936
[ ID] Interval Transfer Bitrate
[ 5] 0.00-1.00 sec 7.12 MBytes 59.7 Mbits/sec
[ 5] 1.00-2.00 sec 8.50 MBytes 71.3 Mbits/sec
[ 5] 2.00-3.00 sec 8.50 MBytes 71.3 Mbits/sec
[ 5] 3.00-4.00 sec 8.38 MBytes 70.3 Mbits/sec
[ 5] 4.00-5.00 sec 8.50 MBytes 71.3 Mbits/sec
[ 5] 5.00-6.00 sec 8.38 MBytes 70.3 Mbits/sec
[ 5] 6.00-7.00 sec 8.62 MBytes 72.4 Mbits/sec
[ 5] 7.00-8.00 sec 8.62 MBytes 72.3 Mbits/sec
[ 5] 8.00-9.00 sec 8.62 MBytes 72.4 Mbits/sec
[ 5] 9.00-10.00 sec 8.62 MBytes 72.4 Mbits/sec
[ 5] 10.00-10.12 sec 896 KBytes 62.3 Mbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval Transfer Bitrate
[ 5] 0.00-10.12 sec 84.8 MBytes 70.3 Mbits/sec receiver

DTS node example:
&ethernet_1g_tile {
...
phy-mode = "rgmii-rxid";
phy-handle = <&phy1>;
...

mdio: mdio {
phy1: ethernet-phy@1 {
...
compatible = "ethernet-phy-id0008.011b";
rx-internal-delay-ps = <1050>;
dapu,tx-inverted-clk;
...
};
};
};

--
Best regards,
Artem Shimko

ChangeLog:
v2:
- Drop debugfs interface
- Simplify RGMII delay reading logic using of_property_read_u32()
- Fix missing newline at end of dapu,dap8211r.yaml (yamllint error)
- Simplify delay property description in DT binding
- Rename tx-inverted-clk to dapu,tx-inverted-clk (vendor prefix)
- Replace enum with multipleOf + maximum for delay validation
- Fix compatible string and tx-internal-delay-ps value in example
- Remove rounding logic, return -EINVAL for unsupported delay values
- Respect DT delay properties for all RGMII modes
- Add polling for self-clearing reset bit instead of fixed sleep
- Remove unused packet generator macros (DAP8211R_PKGC5 and related)
v1:
- https://lore.kernel.org/all/20260713131223.279555-1-a.shimko.dev@xxxxxxxxx/T/#t

Artem Shimko (2):
dt-bindings: net: add DAPU Telecom DAP8211R(I) PHY binding
net: phy: add DAPU Telecom DAP8210R(I) Gigabit Ethernet PHY driver

.../bindings/net/dapu,dap8211r.yaml | 73 +++++
drivers/net/phy/Kconfig | 10 +
drivers/net/phy/Makefile | 1 +
drivers/net/phy/dap8211r.c | 281 ++++++++++++++++++
4 files changed, 365 insertions(+)
create mode 100644 Documentation/devicetree/bindings/net/dapu,dap8211r.yaml
create mode 100644 drivers/net/phy/dap8211r.c

--
2.43.0