Re: [PATCH net v2 3/3] net: stmmac: dwmac1000: stop hardware from dropping checksum-error packets

[Christian Schmidbauer]

On Tue, Nov 10, 2026 at 9:25 PM Jakub Kicinski <kuba@xxxxxxxxxx> wrote:
>
> On Wed,  4 Nov 2026 16:19:13 +0100 Christian Schmidbauer wrote:
> >  /* DMA operation mode defines (start/stop tx/rx are placed in common header)*/
> >  /* Disable Drop TCP/IP csum error */
> > +#define DMA_CONTROL_DT               0x04000000
>
> Maybe just me, since I don't know the HW, but what does _DT stand for
> in this context? Other bits seem to be documented with a comment,
> let's document the new one as well.
>
> Not sure what the comment above the new define is deferring to, either.
> Should it be removed?
>

DT is the Synopsys GMAC field name for bit 26 of the DMA Operation
Mode register, see [1]. The line above the define is actually its
description. The define was originally added in 47dd7a540b8a ("net:
add support for STMicroelectronics Ethernet controllers.") with the
comment on the same line, and when the define got removed in
5a78fd3debad ("net: stmmac: remove unused definitions") earlier this
year, the comment stayed behind.

I will move the comment back onto the line of the define in v3.

[1] https://docs.altera.com/v/u/resources/r642178/cyclone-v-hps-register-map