[PATCH net-next 0/3] net: stmmac: Add UltraRISC DP1000 GMAC support

[Jia Wang]

The UltraRISC DP1000 integrates a Synopsys DesignWare GMAC from the 5.20
series with fixed TX and RX RGMII clock delays that cannot be disabled.

For boards without PCB delays, "rgmii-id" describes the link. Passing this
mode unchanged to the PHY would enable another pair of delays and break the
RGMII timing.

Add a dedicated binding and a small DWMAC glue driver. The driver uses
phy_fix_phy_mode_for_mac_delays() to account for the fixed delays before
attaching the PHY and rejects unsupported RGMII modes.

Tested with:

1. dt_binding_check and dtbs_check.
2. RISC-V build with CONFIG_DWMAC_ULTRARISC=m.
3. Runtime validation on Shenzhen Rongda M0 with a YT8531S PHY and
   Milk-V Titan with an RTL8211F PHY: ultrarisc-dwmac binds and
   establishes a 1000 Mb/s full-duplex link on both boards.

Signed-off-by: Jia Wang <wangjia at ultrarisc.com>
---
Jia Wang (3):
      dt-bindings: net: snps,dwmac: Add UltraRISC DP1000 compatible
      dt-bindings: net: Add UltraRISC DP1000 GMAC
      net: stmmac: Add UltraRISC DP1000 GMAC support

 .../devicetree/bindings/net/snps,dwmac.yaml        |  1 +
 .../bindings/net/ultrarisc,dp1000-gmac.yaml        | 74 ++++++++++++++++++++++
 MAINTAINERS                                        |  6 ++
 drivers/net/ethernet/stmicro/stmmac/Kconfig        | 11 ++++
 drivers/net/ethernet/stmicro/stmmac/Makefile       |  1 +
 .../net/ethernet/stmicro/stmmac/dwmac-ultrarisc.c  | 54 ++++++++++++++++
 6 files changed, 147 insertions(+)
---
base-commit: abdf623ddb75b24659018d3952d8f61937306ae5
change-id: 20260827-dwmac-ultrarisc-7c79f2f80fd1

Best regards,
--  
Jia Wang <wangjia at ultrarisc.com>