Re: [net PATCH V3 2/3] octeontx2-af: CN10KB: fix PFC configuration

[Simon Horman <horms@kernel.org>]

On Tue, Aug 22, 2023 at 01:12:26PM +0200, Paolo Abeni wrote:
> On Tue, 2023-08-22 at 09:16 +0200, Simon Horman wrote:
> > On Mon, Aug 21, 2023 at 10:55:15AM +0530, Suman Ghosh wrote:
> > > From: Hariprasad Kelam <hkelam@marvell.com>
> > > 
> > > The previous patch which added new CN10KB RPM block support,
> > > has a bug due to which PFC is not getting configured properly.
> > > This patch fixes the same.
> > 
> > Hi Suman,
> > 
> > I think it would be useful to describe what the bug is - it seems like an
> > incorrect mask in some cases - and how that might affect users. Better
> > still would be commands for an example usage where the problem previously
> > manifested.
> 
> Suman, please address Simon's feedback above in the new iteration.
> 
> > > 
> > > Fixes: 99c969a83d82 ("octeontx2-pf: Add egress PFC support")
> > > Signed-off-by: Hariprasad Kelam <hkelam@marvell.com>
> > > ---
> > >  drivers/net/ethernet/marvell/octeontx2/af/rpm.c | 17 +++++++++--------
> > >  1 file changed, 9 insertions(+), 8 deletions(-)
> > > 
> > > diff --git a/drivers/net/ethernet/marvell/octeontx2/af/rpm.c b/drivers/net/ethernet/marvell/octeontx2/af/rpm.c
> > > index b4fcb20c3f4f..af21e2030cff 100644
> > > --- a/drivers/net/ethernet/marvell/octeontx2/af/rpm.c
> > > +++ b/drivers/net/ethernet/marvell/octeontx2/af/rpm.c
> > > @@ -355,8 +355,8 @@ int rpm_lmac_enadis_pause_frm(void *rpmd, int lmac_id, u8 tx_pause,
> > >  
> > >  void rpm_lmac_pause_frm_config(void *rpmd, int lmac_id, bool enable)
> > >  {
> > > +	u64 cfg, pfc_class_mask_cfg;
> > >  	rpm_t *rpm = rpmd;
> > > -	u64 cfg;
> > >  
> > >  	/* ALL pause frames received are completely ignored */
> > >  	cfg = rpm_read(rpm, lmac_id, RPMX_MTI_MAC100X_COMMAND_CONFIG);
> > > @@ -380,9 +380,11 @@ void rpm_lmac_pause_frm_config(void *rpmd, int lmac_id, bool enable)
> > >  		rpm_write(rpm, 0, RPMX_CMR_CHAN_MSK_OR, ~0ULL);
> > >  
> > >  	/* Disable all PFC classes */
> > > -	cfg = rpm_read(rpm, lmac_id, RPMX_CMRX_PRT_CBFC_CTL);
> > > +	pfc_class_mask_cfg = is_dev_rpm2(rpm) ? RPM2_CMRX_PRT_CBFC_CTL :
> > > +						RPMX_CMRX_PRT_CBFC_CTL;
> > 
> > Maybe it is overkill, but as this appears at least twice,
> > perhaps a helper would be appropriate.
> 
> I think this is a matter of personal preferences (there is another
> similar chunk with will not fit an helper, short of implementing it
> with a somewhat ugly macro. So the overall code would be asymmetric), 
> 
> I'm fine either way.

Likewise, I don't feel strongly either way.