回覆: [net-next v2 5/7] net: ftgmac100: add pin strap configuration for AST2700
From: Jacky Chou
Date: Mon Nov 18 2024 - 04:37:15 EST
> >> Is there a way to probe the presence of 64-bit addressing from
> >> hardware registers? That would be nicer than triggering it from the
> >> compatible string, given that any future SoC is likely also 64-bit.
>
> I just realized I replied to the wrong email, I meant to send my question as a
> reply to patch 4/7. The patch for the pin strap looks fine.
>
> > There is no register indicated about 64-bit address support in the
> > ftgmac100 of Aspeed 7th generation. Therefore, we use the compatible
> > to configure pin strap and DMA mask.
>
> Later in the series you just unconditionally write the 64-bit address, so it
> appears that the ftgmac100 can actually do 64-bti addressing all along, and
> this doesn't have to be conditional at all, the call to
> dma_set_mask_and_coherent() only tells the kernel that the device can do it,
> which should work on all of them. Since the other devices won't have a larger
> "dma-ranges" configuration in DT, and no RAM above 32-bit addressing, it
> should have no effect.
>
> Just make that part in patch 5 unconditional.
Agree, I got your point.
We tried to add less codes to compatible the older generations.
I will adjust it to normal probe procedure in next version, not use compatible to call
dma_set_mask_and_coherent().
Thank you for your kind reminder.
Thanks,
Jacky