Re: [PATCH net v4 3/3] net: stmmac: Specify hardware capability value when FIFO size isn't specified

Andrew Lunn
2025-01-31T14:48:08Z

> > I'm guessing, but in your setup, i assume the value is never written
> > to a register, hence 0 is O.K. e.g. dwmac1000_dma_operation_mode_rx(),
> > the fifosz value is used to determine if flow control can be used, but
> > is otherwise ignored.
>
> I haven't traced the code, but that fits my assumptions too.

I could probably figure it out using code review, but do you know
which set of DMA operations your hardware uses? A quick look at
dwmac-rk.c i see:

/* If the stmmac is not already selected as gmac4,
* then make sure we fallback to gmac.
*/
if (!plat_dat->has_gmac4)
plat_dat->has_gmac = true;

Which suggests there are two variants of the RockChip MAC.

Andrew