[RFC net-next v1 0/7] highly rfc macb usrio/tsu patches

Conor Dooley
2025-11-20T16:26:24Z

Hey folks,

After doing some debugging of broken tsu/ptp support on mpfs, I've come
up with some very rfc patches that I'd like opinions on - particularly
because they impact a bunch of platforms that I have no access to at all
and have no idea how they work. The at91 platforms I can just ask
Nicolas about (and he already provided some info directly, so I'm not
super worried at least about the usrio portion there) but the others
my gut says are likely incorrect in the driver at the moment.

These patches *are* fairly opinionated and not necessarily technically
correct or w/e. The only thing I am confident in saying that they are is
more deliberate than what's being done at the moment.

At the very least, it'd be good of the soc vendor folks could check
their platforms and see if their usrio stuff actually lines up with what
the driver currently calls "macb_default_usrio". Ours didn't and it was
a nasty surprise.

Cheers,
Conor.

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Conor Dooley (7):
riscv: dts: microchip: add tsu clock to macb on mpfs
net: macb: warn on pclk use as a tsu_clk fallback
net: macb: rename macb_default_usrio to at91_default_usrio as not all
platforms have mii mode control in usrio
net: macb: np4 doesn't need a usrio pointer
dt-bindings: net: macb: add property indicating timer adjust mode
net: macb: afaict, the driver doesn't support tsu timer adjust mode
net: macb: add mpfs specific usrio configuration

.../devicetree/bindings/net/cdns,macb.yaml | 15 +++
arch/riscv/boot/dts/microchip/Makefile.orig | 26 ++++
arch/riscv/boot/dts/microchip/mpfs.dtsi | 8 +-
drivers/net/ethernet/cadence/macb.h | 3 +
drivers/net/ethernet/cadence/macb_main.c | 123 +++++++++++-------
5 files changed, 125 insertions(+), 50 deletions(-)
create mode 100644 arch/riscv/boot/dts/microchip/Makefile.orig

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2.51.0