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 21BBFCD37B5 for ; Mon, 11 May 2026 10:37:03 +0000 (UTC) Received: from mails.dpdk.org (localhost [127.0.0.1]) by mails.dpdk.org (Postfix) with ESMTP id 57B6C40666; Mon, 11 May 2026 12:36:44 +0200 (CEST) Received: from smtpbguseast3.qq.com (smtpbguseast3.qq.com [54.243.244.52]) by mails.dpdk.org (Postfix) with ESMTP id BF0754067D; Mon, 11 May 2026 12:36:41 +0200 (CEST) X-QQ-mid: zesmtpsz3t1778495796ta3cd914a X-QQ-Originating-IP: ReQuNCdFqR4RT9CyoQ9o3bpEij/ZzpV1qq1Il/IXWy8= Received: from DSK-zaiyuwang.trustnetic.com ( [115.204.251.157]) by bizesmtp.qq.com (ESMTP) with id ; Mon, 11 May 2026 18:36:34 +0800 (CST) X-QQ-SSF: 0000000000000000000000000000000 X-QQ-GoodBg: 0 X-BIZMAIL-ID: 7719326627497208825 EX-QQ-RecipientCnt: 4 From: Zaiyu Wang To: dev@dpdk.org Cc: Zaiyu Wang , stable@dpdk.org, Jiawen Wu Subject: [PATCH v4 05/20] net/txgbe: fix inaccuracy in Tx rate limiting Date: Mon, 11 May 2026 18:35:47 +0800 Message-Id: <20260511103604.19724-6-zaiyuwang@trustnetic.com> X-Mailer: git-send-email 2.21.0.windows.1 In-Reply-To: <20260511103604.19724-1-zaiyuwang@trustnetic.com> References: <20260423034024.14404-1-zaiyuwang@trustnetic.com> <20260511103604.19724-1-zaiyuwang@trustnetic.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-QQ-SENDSIZE: 520 Feedback-ID: zesmtpsz:trustnetic.com:qybglogicsvrsz:qybglogicsvrsz3b-0 X-QQ-XMAILINFO: MWdgP8+gtiFRPPvoTkDDAtptopZEBUtlfxdi2vxqhPL2ijkffP2egz0U Je0XC0AW8inX85d//PWhkPrmi+L+/MJIXzJtYKTNWIXFiebQrlbC7KLiFJdYUFOIDB+Qjy8 r/vmrQRJ2mLZ26430zXMZEWEvqTQdIB+MAC2Ab5VcD++G1PRiUBwSA3bOkviMIGPBVqU1sg zJxwnGPEoN3jJj3I9JK/nvMx3sEeHpxq3xFTWkZ7zMtqGzXBCQAn7T9eoeqB1vQj5DPkshC /hsABg43oO4+zI4UVxYst9iZOwIZV7uyYimj4cgrOzAhpfjK8FfcC6j6q6E6KRPLblS9PK8 5TrSItDfwkxTW9TRXEWkOUITyDco1+L5LwQOjQf0DBRQOdKIrGi1oBurx8cBv7pmOeQvwCF 3/Up83VoP1q+QvFo1eKkkdBUBOv+Lnh7dpgfkgnHdG0H5QZRMj9h6qHOcEosv4qrRt888Km 7SLbzoojZ3Dbrs+BN1sV0Flqz0cOAELTu+F1Cz2hqp0Vq/xPLI3YVAG/UkjedBa0v5YgDoX pnzDezZ4HWcdHMkXZf0l47tKkUJW5i8Ozp/i5rk+zP6JN1Q/Ib2cjV6/FNWq3zJFfi9F1cq RYA0ZwKsTgmSqBTTPzXwpYz5gdpWZGMVGALVmMolOoL1v34KKV7NXHYe+GK4zeE152emE6i pR5lVDGT2eKe5lpmIGvgrnPu/KnYtF5sNymaEkVHlMsL8X2I9iLc2GYBFo7jKB9DNJliWop Nz9ruo7UjQPZkl6SFDTGMY5DhbKXKQ0uZK5C5PFWtYZMbYyZ/imavqZtNVJuPfCfvtHR7v5 2HCJ10MT+OjXZdrAHcaeMEHUOMwsnGgAdlC2B2SIa5uW4uG5ZhsFwAFFXLevCnF7j6BTFRG 1L6OptUpEdEGfceDgzZm8ttgzMNLJy9lVYs19vDROVn4yE/yrd/fuOQrkjBwY/07xbPH8Ku zTmi8jgSoB/C5PXoQMEYphhkttTYRTjKdLFnNm3IouxwjmxndOWrP5A+MOeFtNdAqoKygia uylQkuTeS36L+W2pBignhTm3ZD4rhLraNE3sJBbyw6/eHqbJeCIHtxguiTqEE= X-QQ-XMRINFO: MPJ6Tf5t3I/ylTmHUqvI8+Wpn+Gzalws3A== 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 address this, the following changes are made: 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