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

Steven Price
2025-01-31T15:03:17Z

On 31/01/2025 14:47, Andrew Lunn wrote:
>>> 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;

has_gmac4 is false on this board, so has_gmac will be set to true here.

The DT compatible is rockchip,rk3288-gmac

Steve

> Which suggests there are two variants of the RockChip MAC.
>
> Andrew