From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from layka.disroot.org (layka.disroot.org [178.21.23.139]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3B333234964; Fri, 8 Aug 2025 09:44:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=178.21.23.139 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754646261; cv=none; b=ha4WcImKcN5J79/JlP4sVobk5c5p4n2iU0GyISQQDbgIQKGiMfBILOb+yh9+wuweBWljBfjvOn/qJU652txoc+SWtukEp9sWvDkzDwHWdLoGW4XHZsfLAvV8zUjpvtAHMN3TjoIQQrRGCwKBWhqQNrPZO5rqjk6MqS3pT735GnI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754646261; c=relaxed/simple; bh=6F4MMCjDeOJQTOBiI/kQboYeE8sVAqRfvejXM0WLAGY=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=e8IjaOpjd4pPDhuh0DpPe3gdENFkkd60UE3dAgV9s7xmE01zF9c2WuayqXjuZ0NpFLu9r9dOK+18off28sI9rT3rrjA4X2NmyJComCs0BkKrMxp/0xoqrHUF2DHoVlLUoXA27tYiM5IDn+xuXdtAn+voFBH3eENE6FMl2zKfzL8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=disroot.org; spf=pass smtp.mailfrom=disroot.org; dkim=pass (2048-bit key) header.d=disroot.org header.i=@disroot.org header.b=lQkxiJ7G; arc=none smtp.client-ip=178.21.23.139 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=disroot.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=disroot.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=disroot.org header.i=@disroot.org header.b="lQkxiJ7G" Received: from mail01.disroot.lan (localhost [127.0.0.1]) by disroot.org (Postfix) with ESMTP id DCCE225B19; Fri, 8 Aug 2025 11:44:14 +0200 (CEST) X-Virus-Scanned: SPAM Filter at disroot.org Received: from layka.disroot.org ([127.0.0.1]) by localhost (disroot.org [127.0.0.1]) (amavis, port 10024) with ESMTP id v-OBsePsy6H5; Fri, 8 Aug 2025 11:44:13 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=disroot.org; s=mail; t=1754646253; bh=6F4MMCjDeOJQTOBiI/kQboYeE8sVAqRfvejXM0WLAGY=; h=From:To:Cc:Subject:Date; b=lQkxiJ7GL8amk1iNsM0f1VFSXFUbtqeVC9w+I4T/U8Z+AFfrKQQje2rzWNzNiYEah nxgYnsfL6EiaBivK4JdDs0FiOeboMG2FDp6t86MwxqsovXsJje+BJuMKUugHhvLBfl 0d41UVPpYU5Cgk5+P7H/0DYtCwUYXwUvhvg4WycX1uCqWT5SR9mYv5uhA/uDM6J05Q vkcMbk/7CxLjkn1A/GE71bEunM9BGStgv70g6R+Slb6uEVuTZDUe5WFQTdfg22YnBk Oj4YEgEAZ+0tbkLaChdnB8q8IvAPHei2yHp3glhPAS91hBxC3VLTZwl1OOUSrqjOpn tRyYcegkOWIbw== From: Yao Zi To: Drew Fustini , Guo Ren , Fu Wei , Andrew Lunn , "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Ghiti , Emil Renner Berthing , Jisheng Zhang Cc: linux-riscv@lists.infradead.org, netdev@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, Yao Zi Subject: [PATCH net v3 0/3] Fix broken link with TH1520 GMAC when linkspeed changes Date: Fri, 8 Aug 2025 09:36:53 +0000 Message-ID: <20250808093655.48074-2-ziyao@disroot.org> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit It's noted that on TH1520 SoC, the GMAC's link becomes broken after the link speed is changed (for example, running ethtool -s eth0 speed 100 on the peer when negotiated to 1Gbps), but the GMAC could function normally if the speed is brought back to the initial. Just like many other SoCs utilizing STMMAC IP, we need to adjust the TX clock supplying TH1520's GMAC through some SoC-specific glue registers when linkspeed changes. But it's found that after the full kernel startup, reading from them results in garbage and writing to them makes no effect, which is the cause of broken link. Further testing shows perisys-apb4-hclk must be ungated for normal access to Th1520 GMAC APB glue registers, which is neither described in dt-binding nor acquired by the driver. This series expands the dt-binding of TH1520's GMAC to allow an extra "APB glue registers interface clock", instructs the driver to acquire and enable the clock, and finally supplies CLK_PERISYS_APB4_HCLK for TH1520's GMACs in SoC devicetree. Changed from v2 - dt-binding: Drop the Tested-by tag - driver - Improve the commit message to mention the dt-compatibility problem - Add a comment about the dt-compatibility problem - Emit a warning when failed to get APB clock - Stop using the optional clock-getting API since it doesn't help much when we need to handle the missing case. - Collect review tags - Link to v2: https://lore.kernel.org/netdev/20250801091240.46114-1-ziyao@disroot.org/ Changed from v1 - Make apb clock essential in dt-binding - Collect review tags - Link to v1: https://lore.kernel.org/all/20250729093734.40132-1-ziyao@disroot.org/ Yao Zi (3): dt-bindings: net: thead,th1520-gmac: Describe APB interface clock net: stmmac: thead: Get and enable APB clock on initialization riscv: dts: thead: Add APB clocks for TH1520 GMACs .../devicetree/bindings/net/thead,th1520-gmac.yaml | 6 ++++-- arch/riscv/boot/dts/thead/th1520.dtsi | 10 ++++++---- drivers/net/ethernet/stmicro/stmmac/dwmac-thead.c | 14 ++++++++++++++ 3 files changed, 24 insertions(+), 6 deletions(-) -- 2.50.1