Re: [PATCH] [RFC] r8169: check for valid MAC before clobbering

From: Brian Norris
Date: Mon Nov 25 2019 - 20:23:46 EST


On Sat, Nov 23, 2019 at 1:59 AM Heiner Kallweit <hkallweit1@xxxxxxxxx> wrote:
> Realtek doesn't provide any public datasheets, only very few leaked
> old datasheets are available. Only public source of information is
> the vendor drivers: r8168/r8101/r8125.
> Check the vendor drivers for where they read the MAC from.

Thanks, I looked it up, and IIUC the chips I'm using would fall under
the vendor driver's 'CFG_METHOD_21', which does indeed check the GMAC
registers as a priority. (It's also even worse than the upstream
driver here: although it reads out the active MAC register first, it
doesn't end up using the value and instead just clobbers it, even if
the GMAC value is empty/garbage.)

So I guess the vendor driver "always" failed me in the same way, and
it's just the Coreboot authors who were misinformed. :(

Thanks for the pointers,
Brian