From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from lindbergh.monkeyblade.net (lindbergh.monkeyblade.net [23.128.96.19]) (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 7669DD2EF; Sun, 29 Oct 2023 22:41:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b="GAp2S5Le" Received: from madras.collabora.co.uk (madras.collabora.co.uk [IPv6:2a00:1098:0:82:1000:25:2eeb:e5ab]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B60DDC2; Sun, 29 Oct 2023 15:41:28 -0700 (PDT) Received: from [192.168.1.90] (unknown [188.24.143.101]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: cristicc) by madras.collabora.co.uk (Postfix) with ESMTPSA id E600166072BB; Sun, 29 Oct 2023 22:41:25 +0000 (GMT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1698619287; bh=0moYwqGPpKpcCgWCZCbmjb3SQL9UUK8AXxSzTD9M6EM=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=GAp2S5LeolDNT0oMnIU1XOERBBbWg8wPe66a2v7uBCjT0XEL2uOR/xK2jM76GBNkZ g5e8MN3Pt/i8oENbgyJip/7sswIfxUCXn6Wf8pQPBuWG4ooO+Xwwg7SxnSXhjTR8Bj 7Gehm8n2sgo2owH/pQiU4GNiOwJ0NV02FY6al52pwfxMy2bvUEJLGYgGmmyh6YsYmn 6S7/LpukLMtkMX2I25Aq/nj4WJiDUYBxGEX9+rYfeu6ED1sW483Hfh/3UvoGp8rMu8 UagKsbwJ2EUikHgocGXGOchFcKp/R5ps4nE8Lm2T+ymGrnlu0EH04pHnvNsCiq15Tz v/DIB0SxCyOKg== Message-ID: Date: Mon, 30 Oct 2023 00:41:23 +0200 Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 11/12] riscv: dts: starfive: visionfive-v1: Enable gmac and setup phy Content-Language: en-US To: Andrew Lunn Cc: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Emil Renner Berthing , Samin Guo , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexandre Torgue , Jose Abreu , Maxime Coquelin , Richard Cochran , Giuseppe Cavallaro , netdev@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-riscv@lists.infradead.org, linux-stm32@st-md-mailman.stormreply.com, linux-arm-kernel@lists.infradead.org, kernel@collabora.com References: <20231029042712.520010-1-cristian.ciocaltea@collabora.com> <20231029042712.520010-12-cristian.ciocaltea@collabora.com> From: Cristian Ciocaltea In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit On 10/29/23 20:45, Andrew Lunn wrote: > On Sun, Oct 29, 2023 at 06:27:11AM +0200, Cristian Ciocaltea wrote: >> The StarFive VisionFive V1 SBC has a Motorcomm YT8521 PHY supporting >> RGMII-ID, but requires manual adjustment of the RX internal delay to >> work properly. >> >> The default RX delay provided by the driver is 1.95 ns, which proves to >> be too high. Applying a 50% reduction seems to mitigate the issue. > > I'm not so happy this cannot be explained. You are potentially heading > into horrible backwards compatibility problems with old DT blobs and > new kernels once this is explained and fixed. It seems the visionfive-v2 board also required setting some delays, but unfortunately no details were provided: 0104340a67b1 ("riscv: dts: starfive: visionfive 2: Add configuration of mac and phy") Thanks, Cristian