Re: [dpdk-dev] [PATCH v3] nfp: report link speed using hardware info

[Alejandro Lucero <alejandro.lucero@netronome.com>]

On Tue, Dec 6, 2016 at 11:57 AM, Ferruh Yigit <ferruh.yigit@intel.com>
wrote:

> On 12/2/2016 9:05 AM, Alejandro Lucero wrote:
> > Previous reported speed was hardcoded.
> >
> > v3: remove unsed macro
> > v2: using RTE_DIM instead of own macro
> >
> > Signed-off-by: Alejandro Lucero <alejandro.lucero@netronome.com>
> > ---
> >  drivers/net/nfp/nfp_net.c | 28 ++++++++++++++++++++++++++--
> >  1 file changed, 26 insertions(+), 2 deletions(-)
> >
> > diff --git a/drivers/net/nfp/nfp_net.c b/drivers/net/nfp/nfp_net.c
> > index c6b1587..24f3164 100644
> > --- a/drivers/net/nfp/nfp_net.c
> > +++ b/drivers/net/nfp/nfp_net.c
> > @@ -816,6 +816,17 @@ static void nfp_net_read_mac(struct nfp_net_hw *hw)
> >       struct rte_eth_link link, old;
> >       uint32_t nn_link_status;
> >
> > +     static const uint32_t ls_to_ethtool[] = {
> > +             [NFP_NET_CFG_STS_LINK_RATE_UNSUPPORTED] =
> ETH_SPEED_NUM_NONE,
> > +             [NFP_NET_CFG_STS_LINK_RATE_UNKNOWN]     =
> ETH_SPEED_NUM_NONE,
> > +             [NFP_NET_CFG_STS_LINK_RATE_1G]          = ETH_SPEED_NUM_1G,
> > +             [NFP_NET_CFG_STS_LINK_RATE_10G]         =
> ETH_SPEED_NUM_10G,
> > +             [NFP_NET_CFG_STS_LINK_RATE_25G]         =
> ETH_SPEED_NUM_25G,
> > +             [NFP_NET_CFG_STS_LINK_RATE_40G]         =
> ETH_SPEED_NUM_40G,
> > +             [NFP_NET_CFG_STS_LINK_RATE_50G]         =
> ETH_SPEED_NUM_50G,
> > +             [NFP_NET_CFG_STS_LINK_RATE_100G]        =
> ETH_SPEED_NUM_100G,
> > +     };
> > +
> >       PMD_DRV_LOG(DEBUG, "Link update\n");
> >
> >       hw = NFP_NET_DEV_PRIVATE_TO_HW(dev->data->dev_private);
> > @@ -831,8 +842,21 @@ static void nfp_net_read_mac(struct nfp_net_hw *hw)
> >               link.link_status = ETH_LINK_UP;
> >
> >       link.link_duplex = ETH_LINK_FULL_DUPLEX;
> > -     /* Other cards can limit the tx and rx rate per VF */
> > -     link.link_speed = ETH_SPEED_NUM_40G;
> > +
> > +     nn_link_status = (nn_link_status >> NFP_NET_CFG_STS_LINK_RATE_SHIFT)
> &
> > +                      NFP_NET_CFG_STS_LINK_RATE_MASK;
> > +
> > +     if ((NFD_CFG_MAJOR_VERSION_of(hw->ver) < 4) ||
> > +         ((NFD_CFG_MINOR_VERSION_of(hw->ver) == 4) &&
> > +         (NFD_CFG_MINOR_VERSION_of(hw->ver) == 0)))
> > +             link.link_speed = ETH_SPEED_NUM_40G;
>
> Same comment from previous review:
>
> For specific firmware version, speed is still hardcoded to 40G, can you
> please mention from this and if possible its reason in commit log?
>
>
Well, we have old firmware still around and we need to avoid reading this
info from hardware if not supported.
But I guess I could be a more chatty about this in the commit log. I will
send another version.


> > +     else {
> > +             if (nn_link_status == NFP_NET_CFG_STS_LINK_RATE_UNKNOWN ||
>
> Again from previous review:
>
> > This is for checking any wrong value from firmware/hardware.
>
> I see, but removing this check will not change the logic, else branch is
> taken and again same value set.
>
>
OK. I think I can remove the first part of the if clause, because it is
implicit in the second part.
I guess this is what you really meant, and not just to leave the else
statement (without the else, of course). am I right?


> Still if you deliberately prefer to keep it, that is OK.
>
> > +                 nn_link_status >= RTE_DIM(ls_to_ethtool))
> > +                     link.link_speed = ETH_SPEED_NUM_NONE;
> > +             else
> > +                     link.link_speed = ls_to_ethtool[nn_link_status];
> > +     }
> >
> >       if (old.link_status != link.link_status) {
> >               nfp_net_dev_atomic_write_link_status(dev, &link);
> >
>
>