Re: [PATCH net-next 04/10] net: microchip: sparx5: Use chain ids without offsets when enabling rules

[Dan Carpenter]

On Mon, Feb 13, 2023 at 06:07:21PM +0300, Dan Carpenter wrote:
> On Mon, Feb 13, 2023 at 01:48:50PM +0100, Steen Hegelund wrote:
> > Hi Dan,
> > 
> > On Mon, 2023-02-13 at 14:05 +0300, Dan Carpenter wrote:
> > > EXTERNAL EMAIL: Do not click links or open attachments unless you know the
> > > content is safe
> > > 
> > > On Mon, Feb 13, 2023 at 10:24:20AM +0100, Steen Hegelund wrote:
> > > > diff --git a/drivers/net/ethernet/microchip/vcap/vcap_api.c
> > > > b/drivers/net/ethernet/microchip/vcap/vcap_api.c
> > > > index 68e04d47f6fd..9ca0cb855c3c 100644
> > > > --- a/drivers/net/ethernet/microchip/vcap/vcap_api.c
> > > > +++ b/drivers/net/ethernet/microchip/vcap/vcap_api.c
> > > > @@ -1568,6 +1568,18 @@ static int vcap_write_counter(struct
> > > > vcap_rule_internal *ri,
> > > >       return 0;
> > > >  }
> > > > 
> > > > +/* Return the chain id rounded down to nearest lookup */
> > > > +static int vcap_round_down_chain(int cid)
> > > > +{
> > > > +     return cid - (cid % VCAP_CID_LOOKUP_SIZE);
> > > > +}
> > > > +
> > > > +/* Return the chain id rounded up to nearest lookup */
> > > > +static int vcap_round_up_chain(int cid)
> > > > +{
> > > > +     return vcap_round_down_chain(cid + VCAP_CID_LOOKUP_SIZE);
> > > 
> > > Just use the round_up/down() macros.
> > 
> > The only round up/down macros that I am aware of are:
> > 
> >  * round_up - round up to next specified power of 2
> >  * round_down - round down to next specified power of 2
> > 
> > And I cannot use these as the VCAP_CID_LOOKUP_SIZE is not a power of 2.
> > 
> > Did I miss something here?
> > 
> 
> Oh wow.  I didn't realize they needed to be a power of 2.  Sorry!

The correct macros are roundup/down().  Those don't have the power of
two requirement.

regards,
dan carpenter