From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mga06.intel.com (mga06b.intel.com [134.134.136.31]) by mail.toke.dk (Postfix) with ESMTPS id 71BBD9FE0A2 for ; Fri, 14 Apr 2023 17:50:47 +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=EVKY3pk4 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1681487449; x=1713023449; h=from:to:cc:subject:date:message-id:mime-version: content-transfer-encoding; bh=+es8XQvduTZictHBoRTR0IW2Z+9WnoX89NAdi6iQf5A=; b=EVKY3pk4Xkq5VMY2Z2L57dAwDIpXgFkntXxwdUw9qQPbzSLCGYi9uP7p EQw12UEVt82Mms2RUGwIZSUeruF4pvAmm7rCDQCo8PlKpy5ZrbRPVLqHY IswI1Ed0zgED76Sr4VE+m+F9O+pkgxvmHs3E0n2M6OnPqN2vJMWLYiUya i/9tvfHsUm1e2fK7+vcE2XzGrw3It/C7rtQhYNMGgw/Ka/7dPz07ckWTO xnf4H7HDjwCmD5xm8fbPvVDSpu0f+zymrbkH7qOnpLU5EJWTLd43VNvAT tNneYelt7pgJUCitaMMuaiJuhc435tzxfFwXgbJDKs+9dgR+T0ySfU2ML Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10680"; a="407369163" X-IronPort-AV: E=Sophos;i="5.99,197,1677571200"; d="scan'208";a="407369163" Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga104.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Apr 2023 08:49:41 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10680"; a="833581607" X-IronPort-AV: E=Sophos;i="5.99,197,1677571200"; d="scan'208";a="833581607" Received: from p12ill20yoongsia.png.intel.com ([10.88.227.28]) by fmsmga001.fm.intel.com with ESMTP; 14 Apr 2023 08:49:35 -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 , David Laight Date: Fri, 14 Apr 2023 23:49:02 +0800 Message-Id: <20230414154902.2950535-1-yoong.siang.song@intel.com> X-Mailer: git-send-email 2.34.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Message-ID-Hash: 6KVF5PLS7NRYNEG24JK4BI6QPYGBEVIS X-Message-ID-Hash: 6KVF5PLS7NRYNEG24JK4BI6QPYGBEVIS 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 v3 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 Reviewed-by: Jesper Dangaard Brouer --- 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); -- 2.34.1