On Thu, Jul 27, 2023 at 11:44:50AM +0800, Junxian Huang wrote:
>
>
> On 2023/7/24 19:19, Leon Romanovsky wrote:
> > On Fri, Jul 21, 2023 at 05:20:52PM +0800, Junxian Huang wrote:
> >> From: Haoyue Xu <xuhaoyue1@xxxxxxxxxxxxx>
> >>
> >> Previously, there was no way to query the number of lanes for a network
> >> card, so the same netdev_speed would result in a fixed pair of width and
> >> speed. As network card specifications become more diverse, such fixed
> >> mode is no longer suitable, so a method is needed to obtain the correct
> >> width and speed based on the number of lanes.
> >>
> >> This patch retrieves netdev lanes and speed from net_device and
> >> translates them to IB width and speed.
> >>
> >> Signed-off-by: Haoyue Xu <xuhaoyue1@xxxxxxxxxxxxx>
> >> Signed-off-by: Luoyouming <luoyouming@xxxxxxxxxx>
> >> Signed-off-by: Junxian Huang <huangjunxian6@xxxxxxxxxxxxx>
> >> ---
> >> drivers/infiniband/core/verbs.c | 100 +++++++++++++++++++++++++-------
> >> 1 file changed, 79 insertions(+), 21 deletions(-)
> >>
> >> diff --git a/drivers/infiniband/core/verbs.c b/drivers/infiniband/core/verbs.c
> >> index b99b3cc283b6..25367bd6dd97 100644
> >> --- a/drivers/infiniband/core/verbs.c
> >> +++ b/drivers/infiniband/core/verbs.c
> >> @@ -1880,6 +1880,80 @@ int ib_modify_qp_with_udata(struct ib_qp *ib_qp, struct ib_qp_attr *attr,
> >> }
> >> EXPORT_SYMBOL(ib_modify_qp_with_udata);
> >>
> >> +static void ib_get_width_and_speed(u32 netdev_speed, u32 lanes,
> >> + u16 *speed, u8 *width)
> >
> > <...>
> >
> >> + switch (netdev_speed / lanes) {
> >> + case SPEED_2500:
> >> + *speed = IB_SPEED_SDR;
> >> + break;
> >> + case SPEED_5000:
> >> + *speed = IB_SPEED_DDR;
> >> + break;
> >> + case SPEED_10000:
> >> + *speed = IB_SPEED_FDR10;
> >> + break;
> >> + case SPEED_14000:
> >> + *speed = IB_SPEED_FDR;
> >> + break;
> >> + case SPEED_25000:
> >> + *speed = IB_SPEED_EDR;
> >> + break;
> >> + case SPEED_50000:
> >> + *speed = IB_SPEED_HDR;
> >> + break;
> >> + case SPEED_100000:
> >> + *speed = IB_SPEED_NDR;
> >> + break;
> >> + default:
> >> + *speed = IB_SPEED_SDR;
> >> + }
> >
> > How did you come to these translation values?
> >
> > Thanks
>
> The IB spec defines the mapping relationship between IB speed and transfer
> rate. For example, if the transfer rate of is 2.5Gbps(SPEED_2500), the IB
> speed will be set to IB_SPEED_SDR.
Are you referring to "Table 250 - Enumeration of the Rate"?
Thanks
>
> Junxian
