From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by mail.toke.dk (Postfix) with ESMTPS id 0171A9FDCBF for ; Fri, 14 Apr 2023 04:09:59 +0200 (CEST) Authentication-Results: mail.toke.dk; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.a=rsa-sha256 header.s=Intel header.b=PtGVlind DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1681438200; x=1712974200; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=V6yxTKpwndzirxcebJgSFtOtxmxSXQn9YpBYMRBfZ4M=; b=PtGVlindhL5I7wDAtp8MA0/GfsRJRMj3FGwFADvZzeAE0w32PVGxts6c blww8S5cgOmeK26uEPm05WkGAtrA9YBulSmJPp4Ra3erQ/09AnXyc/op5 7SkPDDzLmY8Ghl9dw0jMrxAHH8Ftnbiii6eTg1qPUJRV77LrMoD9yffyc T4mFLnt/T7E1o2JXE6v4/TZOj+l5R2uKM89WDCjYCpg3kqWuKmy484Jmf Y3CxCmVkieqkJYEdcOcjaY4FTbmNp9Qw7ZGTe+/VskptOn1fUsihYr2A1 S4SjLmC3caOqc9w1lWtNaR3twXXBeh2jcPXnF9egPT2YJOWsiI4PU4DP/ Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10679"; a="333124449" X-IronPort-AV: E=Sophos;i="5.99,195,1677571200"; d="scan'208";a="333124449" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Apr 2023 19:09:57 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10679"; a="779019528" X-IronPort-AV: E=Sophos;i="5.99,195,1677571200"; d="scan'208";a="779019528" Received: from p12ill20yoongsia.png.intel.com ([10.88.227.28]) by FMSMGA003.fm.intel.com with ESMTP; 13 Apr 2023 19:09:51 -0700 From: Song Yoong Siang To: Jesse Brandeburg , Tony Nguyen , "David S . Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Alexei Starovoitov , Daniel Borkmann , Jesper Dangaard Brouer , John Fastabend , Maciej Fijalkowski , Vedang Patel , Jithu Joseph , Andre Guedes , Jesper Dangaard Brouer , Stanislav Fomichev , Jacob Keller Date: Fri, 14 Apr 2023 10:09:15 +0800 Message-Id: <20230414020915.1869456-1-yoong.siang.song@intel.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Message-ID-Hash: Q747UGTVZFGRU7ERAEJ2ONSV4SCUUVVX X-Message-ID-Hash: Q747UGTVZFGRU7ERAEJ2ONSV4SCUUVVX X-MailFrom: yoong.siang.song@intel.com X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: intel-wired-lan@lists.osuosl.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, bpf@vger.kernel.org, xdp-hints@xdp-project.net, stable@vger.kernel.org, Song Yoong Siang X-Mailman-Version: 3.3.8 Precedence: list Subject: [xdp-hints] [PATCH net v2 1/1] igc: read before write to SRRCTL register List-Id: XDP hardware hints design discussion Archived-At: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: 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 Command on Link Partner: echo -n skb | nc -u -q1 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: # 5.14+ Signed-off-by: Song Yoong Siang Reviewed-by: Jacob Keller --- v2 changelog: - Fix indention --- drivers/net/ethernet/intel/igc/igc_base.h | 7 +++++-- drivers/net/ethernet/intel/igc/igc_main.c | 5 ++++- 2 files changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/intel/igc/igc_base.h b/drivers/net/ethernet/intel/igc/igc_base.h index 7a992befca24..b95007d51d13 100644 --- a/drivers/net/ethernet/intel/igc/igc_base.h +++ b/drivers/net/ethernet/intel/igc/igc_base.h @@ -87,8 +87,11 @@ 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_BSIZEPKT_MASK GENMASK(6, 0) +#define IGC_SRRCTL_BSIZEPKT_SHIFT 10 /* Shift _right_ */ +#define IGC_SRRCTL_BSIZEHDRSIZE_MASK GENMASK(13, 8) +#define IGC_SRRCTL_BSIZEHDRSIZE_SHIFT 2 /* Shift _left_ */ +#define IGC_SRRCTL_DESCTYPE_MASK GENMASK(27, 25) #define IGC_SRRCTL_DESCTYPE_ADV_ONEBUF 0x02000000 #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..88fac08d8a14 100644 --- a/drivers/net/ethernet/intel/igc/igc_main.c +++ b/drivers/net/ethernet/intel/igc/igc_main.c @@ -641,7 +641,10 @@ 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 = rd32(IGC_SRRCTL(reg_idx)); + srrctl &= ~(IGC_SRRCTL_BSIZEPKT_MASK | IGC_SRRCTL_BSIZEHDRSIZE_MASK | + IGC_SRRCTL_DESCTYPE_MASK); + srrctl |= IGC_RX_HDR_LEN << IGC_SRRCTL_BSIZEHDRSIZE_SHIFT; srrctl |= buf_size >> IGC_SRRCTL_BSIZEPKT_SHIFT; srrctl |= IGC_SRRCTL_DESCTYPE_ADV_ONEBUF; -- 2.34.1