From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B4E02486E74 for ; Wed, 29 Jul 2026 13:53:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785333203; cv=none; b=nzTVxC3AIuqMYmcP3jvQaJzQqXQrHvucyBx590XWjq5/iubK2XIKk+5lJ76zZCSJkR7cHPYnyKHCucvZTGQiidrA70pdTExUUbMAcI8bGkNkqeN+rKl8KSRlO5XmNurKP5XmJl4va0Tuf+1gAKv/9uQQOFD3lEDUnmJvOpTQtZg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1785333203; c=relaxed/simple; bh=uDJ+08cuSCaS1YWSE3x8VcHQS1BlGZH1vuNimY7AjpM=; h=Subject:To:Cc:From:Date:Message-ID:MIME-Version:Content-Type; b=qd7267/8corRZIbk3WVn035k+h4ZlthCket5eEX5mafA5wreQaxd49sL4DqAbciQKJg7QaqkaIeYsT2YkK/ySui2GyMXj4L2gCAHvR79tSn/6RiYjvoPXCmulbGrjGqNUveYuodq57s3ZrssjnL0NnCrs+wvvKJ/6Ttx4is73ek= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=jTBBnoYo; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="jTBBnoYo" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8762E1F000E9; Wed, 29 Jul 2026 13:53:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1785333198; bh=YCjePWFLpbvwfJ+9KhwlsrttaB8k5Vm7KXwKgw7gp0k=; h=Subject:To:Cc:From:Date; b=jTBBnoYo2S3iJC7m9HG22gDiRq4qwKqZ80eHdCFLGZ5B/2w7a4fDiuPb52AhlqdkY ka/H4N05AAdF41DFOW9KmVoLKnzHLXS1IevZeXdqna94uKR+DbHNMsrfWQNrCdFN/0 dzWqUDje2CS0tWxBdJBvYCQKNRr7ZsIvrNJDknBY= Subject: FAILED: patch "[PATCH] net: pcs: xpcs: fix SGMII state reading" failed to apply to 6.12-stable tree To: coiaprant@gmail.com,jiawenwu@trustnetic.com,kuba@kernel.org,maxime.chevallier@bootlin.com Cc: From: Date: Wed, 29 Jul 2026 15:53:04 +0200 Message-ID: <2026072904-shallow-icing-2a9f@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit The patch below does not apply to the 6.12-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.12.y git checkout FETCH_HEAD git cherry-pick -x def9a4745e105145133e442dd8a1c126caf0f553 # git commit -s git send-email --to '' --in-reply-to '2026072904-shallow-icing-2a9f@gregkh' --subject-prefix 'PATCH 6.12.y' 'HEAD^..' Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From def9a4745e105145133e442dd8a1c126caf0f553 Mon Sep 17 00:00:00 2001 From: Coia Prant Date: Fri, 17 Jul 2026 15:43:25 +0800 Subject: [PATCH] net: pcs: xpcs: fix SGMII state reading Commit 2a22b7ae2fa3 ("net: pcs: xpcs: adapt Wangxun NICs for SGMII mode") added a path in xpcs_get_state_c37_sgmii() that reads speed/duplex from BMCR after AN completes. However, BMCR does not reflect the negotiated result on the hardware where this has been tested: - On RK3568 (MAC side SGMII), BMCR returns a fixed hardware reset value - Wangxun engineer Jiawen Wu confirmed that on their side, "BMCR looks like it only wants to be return as 0" [0] The correct information is available in CL37_ANSGM_STS, which contains the actual link status and negotiated speed/duplex. This bug was previously masked by phylink core, which overrides the PCS link state with the PHY state when a PHY is present: /* If we have a phy, the "up" state is the union of both the * PHY and the MAC */ if (phy) link_state.link &= pl->phy_state.link; Thus, when the link is down, the PHY's link_down state is applied on top of whatever the PCS reports, hiding the broken PCS state reading path. Modify xpcs_get_state_c37_sgmii() to: 1. Read link state from CL37_ANSGM_STS 2. If link is up, report speed/duplex from CL37_ANSGM_STS 3. Remove the broken BMCR reading path entirely Also properly set state->an_complete to reflect the AN completion status, and clear CL37_ANCMPLT_INTR when link is down to avoid stale state. [0] https://lore.kernel.org/all/000c01dd1593$2ac0b0f0$804212d0$@trustnetic.com/ Fixes: 2a22b7ae2fa3 ("net: pcs: xpcs: adapt Wangxun NICs for SGMII mode") Cc: stable@vger.kernel.org Tested-by: Jiawen Wu Signed-off-by: Coia Prant Tested-by: Maxime Chevallier Reviewed-by: Maxime Chevallier Link: https://patch.msgid.link/20260717074324.3250043-2-coiaprant@gmail.com Signed-off-by: Jakub Kicinski diff --git a/drivers/net/pcs/pcs-xpcs.c b/drivers/net/pcs/pcs-xpcs.c index e69fa2f0a0e8..0337e2bcc012 100644 --- a/drivers/net/pcs/pcs-xpcs.c +++ b/drivers/net/pcs/pcs-xpcs.c @@ -1058,6 +1058,7 @@ static int xpcs_get_state_c37_sgmii(struct dw_xpcs *xpcs, /* Reset link_state */ state->link = false; + state->an_complete = false; state->speed = SPEED_UNKNOWN; state->duplex = DUPLEX_UNKNOWN; state->pause = 0; @@ -1069,6 +1070,8 @@ static int xpcs_get_state_c37_sgmii(struct dw_xpcs *xpcs, if (ret < 0) return ret; + state->an_complete = ret & DW_VR_MII_AN_STS_C37_ANCMPLT_INTR; + if (ret & DW_VR_MII_C37_ANSGM_SP_LNKSTS) { int speed_value; @@ -1086,35 +1089,14 @@ static int xpcs_get_state_c37_sgmii(struct dw_xpcs *xpcs, state->duplex = DUPLEX_FULL; else state->duplex = DUPLEX_HALF; - } else if (ret == DW_VR_MII_AN_STS_C37_ANCMPLT_INTR) { - int speed, duplex; - state->link = true; - - speed = xpcs_read(xpcs, MDIO_MMD_VEND2, MII_BMCR); - if (speed < 0) - return speed; - - speed &= BMCR_SPEED100 | BMCR_SPEED1000; - if (speed == BMCR_SPEED1000) - state->speed = SPEED_1000; - else if (speed == BMCR_SPEED100) - state->speed = SPEED_100; - else if (speed == 0) - state->speed = SPEED_10; - - duplex = xpcs_read(xpcs, MDIO_MMD_VEND2, MII_ADVERTISE); - if (duplex < 0) - return duplex; - - if (duplex & ADVERTISE_1000XFULL) - state->duplex = DUPLEX_FULL; - else if (duplex & ADVERTISE_1000XHALF) - state->duplex = DUPLEX_HALF; - - xpcs_write(xpcs, MDIO_MMD_VEND2, DW_VR_MII_AN_INTR_STS, 0); + return 0; } + /* Clear AN complete status or interrupt */ + if (state->an_complete) + xpcs_write(xpcs, MDIO_MMD_VEND2, DW_VR_MII_AN_INTR_STS, 0); + return 0; }