Song Yoong Siang 3ce29c17dc igc: read before write to SRRCTL register ... 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: fc9df2a0b5 ("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> Tested-by: Jesper Dangaard Brouer <brouer@redhat.com> Tested-by: Naama Meir <naamax.meir@linux.intel.com> Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com> Reviewed-by: Leon Romanovsky <leonro@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>		2023-05-03 09:19:11 +01:00
..
igc_base.c
igc_base.h	igc: read before write to SRRCTL register	2023-05-03 09:19:11 +01:00
igc_defines.h	igc: Remove obsolete DMA coalescing code	2023-03-21 11:37:16 -07:00
igc_diag.c
igc_diag.h
igc_dump.c
igc_ethtool.c	igc: Add qbv_config_change_errors counter	2023-03-07 13:45:56 -08:00
igc_hw.h	igc: offload queue max SDU from tc-taprio	2023-03-07 13:45:56 -08:00
igc_i225.c	igc: Remove obsolete DMA coalescing code	2023-03-21 11:37:16 -07:00
igc_i225.h
igc_mac.c
igc_mac.h
igc_main.c	igc: read before write to SRRCTL register	2023-05-03 09:19:11 +01:00
igc_nvm.c
igc_nvm.h
igc_phy.c
igc_phy.h
igc_ptp.c
igc_regs.h	igc: Remove obsolete DMA coalescing code	2023-03-21 11:37:16 -07:00
igc_tsn.c	igc: Add qbv_config_change_errors counter	2023-03-07 13:45:56 -08:00
igc_tsn.h
igc_xdp.c
igc_xdp.h
igc.h	igc: Clean up and optimize watchdog task	2023-03-07 13:45:56 -08:00
Makefile