Messages in this thread | | | From | Jesper Dangaard Brouer <> | Date | Fri, 14 Apr 2023 22:05:05 +0200 | Subject | Re: [PATCH net v3 1/1] igc: read before write to SRRCTL register |
| |
On 14/04/2023 17.49, Song Yoong Siang wrote: > igc_configure_rx_ring() function will be called as part of XDP program > setup. If Rx hardware timestamp is enabled prio to XDP program setup, > this timestamp enablement will be overwritten when buffer size is > written into SRRCTL register. > > Thus, this commit read the register value before write to SRRCTL > register. This commit is tested by using xdp_hw_metadata bpf selftest > tool. The tool enables Rx hardware timestamp and then attach XDP program > to igc driver. It will display hardware timestamp of UDP packet with > port number 9092. Below are detail of test steps and results. > > Command on DUT: > sudo ./xdp_hw_metadata <interface name> > > Command on Link Partner: > echo -n skb | nc -u -q1 <destination IPv4 addr> 9092 > > Result before this patch: > skb hwtstamp is not found! > > Result after this patch: > found skb hwtstamp = 1677800973.642836757 > > Optionally, read PHC to confirm the values obtained are almost the same: > Command: > sudo ./testptp -d /dev/ptp0 -g > Result: > clock time: 1677800973.913598978 or Fri Mar 3 07:49:33 2023 > > Fixes: fc9df2a0b520 ("igc: Enable RX via AF_XDP zero-copy") > Cc: <stable@vger.kernel.org> # 5.14+ > Signed-off-by: Song Yoong Siang <yoong.siang.song@intel.com> > Reviewed-by: Jacob Keller <jacob.e.keller@intel.com> > Reviewed-by: Jesper Dangaard Brouer <brouer@redhat.com> > ---
LGTM, thank for the adjustments :-)
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
> v2 -> v3: Refactor SRRCTL definitions to more human readable definitions > v1 -> v2: Fix indention > --- > drivers/net/ethernet/intel/igc/igc_base.h | 11 ++++++++--- > drivers/net/ethernet/intel/igc/igc_main.c | 7 +++++-- > 2 files changed, 13 insertions(+), 5 deletions(-) > > diff --git a/drivers/net/ethernet/intel/igc/igc_base.h b/drivers/net/ethernet/intel/igc/igc_base.h > index 7a992befca24..9f3827eda157 100644 > --- a/drivers/net/ethernet/intel/igc/igc_base.h > +++ b/drivers/net/ethernet/intel/igc/igc_base.h > @@ -87,8 +87,13 @@ union igc_adv_rx_desc { > #define IGC_RXDCTL_SWFLUSH 0x04000000 /* Receive Software Flush */ > > /* SRRCTL bit definitions */ > -#define IGC_SRRCTL_BSIZEPKT_SHIFT 10 /* Shift _right_ */ > -#define IGC_SRRCTL_BSIZEHDRSIZE_SHIFT 2 /* Shift _left_ */ > -#define IGC_SRRCTL_DESCTYPE_ADV_ONEBUF 0x02000000 > +#define IGC_SRRCTL_BSIZEPKT_MASK GENMASK(6, 0) > +#define IGC_SRRCTL_BSIZEPKT(x) FIELD_PREP(IGC_SRRCTL_BSIZEPKT_MASK, \ > + (x) / 1024) /* in 1 KB resolution */ > +#define IGC_SRRCTL_BSIZEHDR_MASK GENMASK(13, 8) > +#define IGC_SRRCTL_BSIZEHDR(x) FIELD_PREP(IGC_SRRCTL_BSIZEHDR_MASK, \ > + (x) / 64) /* in 64 bytes resolution */ > +#define IGC_SRRCTL_DESCTYPE_MASK GENMASK(27, 25) > +#define IGC_SRRCTL_DESCTYPE_ADV_ONEBUF FIELD_PREP(IGC_SRRCTL_DESCTYPE_MASK, 1) > > #endif /* _IGC_BASE_H */ > diff --git a/drivers/net/ethernet/intel/igc/igc_main.c b/drivers/net/ethernet/intel/igc/igc_main.c > index 25fc6c65209b..a2d823e64609 100644 > --- a/drivers/net/ethernet/intel/igc/igc_main.c > +++ b/drivers/net/ethernet/intel/igc/igc_main.c > @@ -641,8 +641,11 @@ static void igc_configure_rx_ring(struct igc_adapter *adapter, > else > buf_size = IGC_RXBUFFER_2048; > > - srrctl = IGC_RX_HDR_LEN << IGC_SRRCTL_BSIZEHDRSIZE_SHIFT; > - srrctl |= buf_size >> IGC_SRRCTL_BSIZEPKT_SHIFT; > + srrctl = rd32(IGC_SRRCTL(reg_idx)); > + srrctl &= ~(IGC_SRRCTL_BSIZEPKT_MASK | IGC_SRRCTL_BSIZEHDR_MASK | > + IGC_SRRCTL_DESCTYPE_MASK); > + srrctl |= IGC_SRRCTL_BSIZEHDR(IGC_RX_HDR_LEN); > + srrctl |= IGC_SRRCTL_BSIZEPKT(buf_size); > srrctl |= IGC_SRRCTL_DESCTYPE_ADV_ONEBUF; > > wr32(IGC_SRRCTL(reg_idx), srrctl);
| |