From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mails.dpdk.org (mails.dpdk.org [217.70.189.124]) by smtp.lore.kernel.org (Postfix) with ESMTP id 201C3FF8875 for ; Wed, 29 Apr 2026 10:26:35 +0000 (UTC) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 318A540670; Wed, 29 Apr 2026 12:26:26 +0200 (CEST) Received: from smtpbgsg2.qq.com (smtpbgsg2.qq.com [54.254.200.128]) by mails.dpdk.org (Postfix) with ESMTP id 716AA40676; Wed, 29 Apr 2026 12:26:23 +0200 (CEST) X-QQ-mid: esmtpgz10t1777458378t82a1803e X-QQ-Originating-IP: bicVkK9GcwhsstuHfa4/UpL/TDWf2wMtORscKntq+/k= Received: from DSK-zaiyuwang.trustnetic.com ( [36.24.191.108]) by bizesmtp.qq.com (ESMTP) with id ; Wed, 29 Apr 2026 18:26:16 +0800 (CST) X-QQ-SSF: 0000000000000000000000000000000 X-QQ-GoodBg: 0 X-BIZMAIL-ID: 408695603032947641 EX-QQ-RecipientCnt: 4 From: Zaiyu Wang To: dev@dpdk.org Cc: Zaiyu Wang , stable@dpdk.org, Jiawen Wu Subject: [PATCH v2 05/20] net/txgbe: fix inaccuracy in TX rate limiting Date: Wed, 29 Apr 2026 18:24:59 +0800 Message-Id: <20260429102515.58880-6-zaiyuwang@trustnetic.com> X-Mailer: git-send-email 2.21.0.windows.1 In-Reply-To: <20260429102515.58880-1-zaiyuwang@trustnetic.com> References: <20260423034024.14404-1-zaiyuwang@trustnetic.com> <20260429102515.58880-1-zaiyuwang@trustnetic.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-QQ-SENDSIZE: 520 Feedback-ID: esmtpgz:trustnetic.com:qybglogicsvrsz:qybglogicsvrsz3b-0 X-QQ-XMAILINFO: Nr5N425iK0yrKGEjTI+ref/Mu8vSH4hDYxeOv6QlBD+ZOlt4ffRAdNfj DXF+9M8Gcbk7i9XohT51GEWQpSpNqS+K8Z7z/Jvm+apXkMO3KtlFXRapTL1040MpK3S/rcL TkACnS/XWRmkx6X7VLzbfv9N00i7Z7h+9NvT6NJeb7YMdFW52epU4SA/+Mlv5eb7w+dq7Kl 1dN7zw/Ki8WC9Xgai8tjp+KBeWXzWuuYZjLgph0qOSQ06RCku6qgAtNU9kpJjqkRr/WS0pU aG2Noxpn574pQil6sZr/FQuSAASY9QQwiNfv7keRfoL+BBQCXHNstVf9+0lWt5LT/lZs5mf ERVMpYq19Owj8fWxowL6cgzUERaTcyiF3yPgFvt0N6Y+QAwsj31RPpAWNVrw5A/r00x/Q4t Dy8bUSfgurdgH0SWfSq8zi+RcN122baSp+C47kD6xHJzsIcis81EcRyO/XUm7gqfd8Xy7qW cQny0zS5uvAV2qoWtZt2RLTo/jLAIBaQ0n0Ws5kEEriqe9yFacwEexl79c96oe89esb57UM nJhoOHyhMhKTwITnpJJybhURWnWMpHXGi+Fzg0DxYcDMljqpHYPFLDiIhRTL0Vp/xH+2aB4 20JAc+a6Lf6N3F9iE+F90nWb8iPj+S4MZGqJrXPTbWr7cKR16Ha4Uwxv9lAkaoL1kWWl+my F8eCSk/y+wW+/yWyW990PQyOdwfwLt2S46hvErpwK2vgublhho9NQC5Lnf4KhNGSHFew0tU 6o0PEVED4FIVX0VOKiwHdWO021JOplNWZFwvdL4H7Z94ZQWEhvrucYFsIGbPvVkcGPs7jrk ee8NBVDShLSDEx4C/K6DunIiENEXhZlK4fsvFiuf6Jeomm1NbQp8FksYwfyiXOpj3GNOIXs BzOCbK5CzPXjP0xm7PQtpuh6QXSG+7y/drryWbKO9O23W2pP+tR6qCT4PD+PdxQfBa4Dzvh k+LDHtsnnvIFzPQpsseNmN7qSU0yw9fEPY3Q3JBpYpP76PcaWrt0op3wmOBgJQA3jK84q1i ShEGkvuT6hsW59OxVL1xRzLVR4ifPo84ioY9D31/Nk5ZUyHlfY X-QQ-XMRINFO: MSVp+SPm3vtSI1QTLgDHQqIV1w2oNKDqfg== X-QQ-RECHKSPAM: 0 X-BeenThere: dev@dpdk.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: DPDK patches and discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: dev-bounces@dpdk.org Amber-lite NIC's TX rate limiting has large deviations for small packets. To fix this issue, there are some changes: 1. Set TDM_RL_ADJ (0x1820c) to 21B (includes 7B Ethernet preamble, 1B SFD, 1B EFD, and 12B IPG). 2) Remove the rate offset in the driver (e.g., 105 / 100, a rough compensation value from Linux kernel driver tests). After these changes, accuracy deviation for 64B packets is within ~5%, while large packets show lower deviation. Fixes: a309ab43acf3 ("net/txgbe: support Tx queue rate limiting for Amber-Lite") Cc: stable@dpdk.org Signed-off-by: Zaiyu Wang --- drivers/net/txgbe/base/txgbe_regs.h | 1 + drivers/net/txgbe/txgbe_ethdev.c | 2 +- 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/net/txgbe/base/txgbe_regs.h b/drivers/net/txgbe/base/txgbe_regs.h index 95c585a025..060757323a 100644 --- a/drivers/net/txgbe/base/txgbe_regs.h +++ b/drivers/net/txgbe/base/txgbe_regs.h @@ -1670,6 +1670,7 @@ enum txgbe_5tuple_protocol { #define TXGBE_TDM_FACTOR_INT_SHIFT 16 #define TXGBE_TDM_FACTOR_FRA_SHIFT 2 +#define TXGBE_TDM_RL_ADJ 0x1820C #define TXGBE_TDM_RL_VM_IDX 0x018218 #define TXGBE_TDM_RL_VM_CFG 0x01821C #define TXGBE_TDM_RL_CFG 0x018400 diff --git a/drivers/net/txgbe/txgbe_ethdev.c b/drivers/net/txgbe/txgbe_ethdev.c index 779874aac9..414107d7a7 100644 --- a/drivers/net/txgbe/txgbe_ethdev.c +++ b/drivers/net/txgbe/txgbe_ethdev.c @@ -4314,7 +4314,6 @@ txgbe_set_queue_rate_limit(struct rte_eth_dev *dev, u16 frac; link_speed = dev->data->dev_link.link_speed; - tx_rate = tx_rate * 105 / 100; /* Calculate the rate factor values to set */ factor_int = link_speed / tx_rate; frac = (link_speed % tx_rate) * 10000 / tx_rate; @@ -4324,6 +4323,7 @@ txgbe_set_queue_rate_limit(struct rte_eth_dev *dev, factor_fra = 0; } + wr32(hw, TXGBE_TDM_RL_ADJ, 21); wr32(hw, TXGBE_TDM_RL_QUEUE_IDX, queue_idx); wr32m(hw, TXGBE_TDM_RL_QUEUE_CFG, TXGBE_TDM_FACTOR_INT_MASK, factor_int << TXGBE_TDM_FACTOR_INT_SHIFT); -- 2.21.0.windows.1