[PATCH net-next 0/3] net: stmmac: dwmac-rk: add RK3576 GMAC 25M refout support

[Gavin Gao]

Hi,

Some Rockchip GMAC instances can provide a 25 MHz reference clock output
for an external RGMII PHY. Boards already describe the MAC clock direction
with clock_in_out = "output", but the dwmac-rk driver does not currently
request or enable the corresponding 25 MHz reference output clock.

On RK3576, this means the REFCLKO25M_GMACx_OUT clock may be disabled by
the common clock framework as unused, even though the board expects the
GMAC block to provide the PHY reference clock.

This series adds an optional "clk_mac_25m_refout" clock name to the
Rockchip DWMAC binding, wires it up for RK3576 GMAC0/GMAC1, and enables
it from the dwmac-rk driver when the MAC is configured for RGMII output
clock mode.

The clock remains optional, so existing device trees and SoCs are not
affected.

Tested on a PicoCOM RK3576 ACP board with a Motorcomm YT8521 PHY.
The GMAC 25 MHz reference clock output remains active and Ethernet works.

Gavin Gao (3):
  dt-bindings: net: rockchip-dwmac: Add 25M refout clock
  arm64: dts: rockchip: Add RK3576 GMAC 25M refout clocks
  net: stmmac: dwmac-rk: Enable RGMII 25M refout clock

 .../bindings/net/rockchip-dwmac.yaml          |  1 +
 arch/arm64/boot/dts/rockchip/rk3576.dtsi      |  8 ++---
 .../net/ethernet/stmicro/stmmac/dwmac-rk.c    | 33 ++++++++++++++++++-
 3 files changed, 37 insertions(+), 5 deletions(-)

-- 
2.55.0