From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:55650 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727260AbeJICFd (ORCPT ); Mon, 8 Oct 2018 22:05:33 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Maciej S. Szmigiero" , "David S. Miller" , Sasha Levin Subject: [PATCH 4.18 116/168] r8169: set TxConfig register after TX / RX is enabled, just like RxConfig Date: Mon, 8 Oct 2018 20:31:36 +0200 Message-Id: <20181008175624.455342059@linuxfoundation.org> In-Reply-To: <20181008175620.043587728@linuxfoundation.org> References: <20181008175620.043587728@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org List-ID: 4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: "Maciej S. Szmigiero" [ Upstream commit f74dd480cf4e31e12971c58a1d832044db945670 ] Commit 3559d81e76bf ("r8169: simplify rtl_hw_start_8169") changed order of two register writes: 1) Caused RxConfig to be written before TX / RX is enabled, 2) Caused TxConfig to be written before TX / RX is enabled. At least on XIDs 10000000 ("RTL8169sb/8110sb") and 18000000 ("RTL8169sc/8110sc") such writes are ignored by the chip, leaving values in these registers intact. Change 1) was reverted by commit 05212ba8132b42 ("r8169: set RxConfig after tx/rx is enabled for RTL8169sb/8110sb devices"), however change 2) wasn't. In practice, this caused TxConfig's "InterFrameGap time" and "Max DMA Burst Size per Tx DMA Burst" bits to be zero dramatically reducing TX performance (in my tests it dropped from around 500Mbps to around 50Mbps). This patch fixes the issue by moving TxConfig register write a bit later in the code so it happens after TX / RX is already enabled. Fixes: 05212ba8132b42 ("r8169: set RxConfig after tx/rx is enabled for RTL8169sb/8110sb devices") Signed-off-by: Maciej S. Szmigiero Signed-off-by: David S. Miller Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/net/ethernet/realtek/r8169.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/drivers/net/ethernet/realtek/r8169.c +++ b/drivers/net/ethernet/realtek/r8169.c @@ -5150,13 +5150,13 @@ static void rtl_hw_start(struct rtl8169 rtl_set_rx_max_size(tp); rtl_set_rx_tx_desc_registers(tp); - rtl_set_tx_config_registers(tp); RTL_W8(tp, Cfg9346, Cfg9346_Lock); /* Initially a 10 us delay. Turned it into a PCI commit. - FR */ RTL_R8(tp, IntrMask); RTL_W8(tp, ChipCmd, CmdTxEnb | CmdRxEnb); rtl_init_rxcfg(tp); + rtl_set_tx_config_registers(tp); rtl_set_rx_mode(tp->dev); /* no early-rx interrupts */