Thread (16 messages) 16 messages, 6 authors, 2026-03-30

Re: [PATCH net-next v2] net: phy: bcm84881: add BCM84891/BCM84892 support

From: "Russell King (Oracle)" <linux@armlinux.org.uk>
Date: 2026-03-30 23:34:19

On Tue, Mar 24, 2026 at 07:06:01PM +0000, Daniel Wagner wrote:
The BCM84891 and BCM84892 are 10GBASE-T PHYs in the same family as the
BCM84881, sharing the register map and most callbacks. They add USXGMII
as a host interface mode.

bcm8489x_config_init() is separate from bcm84881_config_init(): it
allows only USXGMII (the only host mode available on the tested
hardware) and clears MDIO_CTRL1_LPOWER, which is set at boot on the
tested platform. Does not recur on ifdown/ifup, cable events, or
link-partner advertisement changes, so config_init is sufficient.

For USXGMII, read_status() skips the 0x4011 host-mode register: it
returns the same value regardless of negotiated copper speed (USXGMII
symbol replication). Speed comes from phy_resolve_aneg_linkmode() via
standard C45 AN resolution.

Tested on TRENDnet TEG-S750 (RTL9303 + 1x BCM84891 + 4x BCM84892)
running OpenWrt, where the MDIO controller driver is currently
OpenWrt-specific. Link verified at 100M, 1G, 2.5G, 10G.

Signed-off-by: Daniel Wagner <redacted>
When you re-post, please do not thread to the previous patch versions.

Reviewed-by: Russell King (Oracle) <redacted>

Thanks!

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
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