From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtpout-03.galae.net (smtpout-03.galae.net [185.246.85.4]) (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 57DBB3DF001; Thu, 3 Sep 2026 08:16:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=185.246.85.4 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788423399; cv=none; b=kDpBOsamRDzaUYANpMMK8lHTMDvtODXagsnolhswqpifh+M0DsrQVc3aFjltL7t3d7Uz/AjOqk3+FVRQebJb9vBvY7pPgn2aLPMeCVW44z9QQ5qh5FHJgq6IhpvvzBsdPeNe+Vx7VkHeZB+BqcEM4s7qfy0C5tTcRmrLpj8Rz5U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788423399; c=relaxed/simple; bh=YLfdgrdlzJj/pA2hZxsG9Y8cox2mPc65rtCPL4VHF9o=; h=From:To:Cc:Subject:In-Reply-To:References:Date:Message-ID: MIME-Version:Content-Type; b=Fl1Frmsw5upd6PlXeFRSl8SW/eJL9QQEW8dYMXJ+u0o1AxFSPaTLpPHHxAVIwXkKkE8YUu8GooUffuixq+mXkD+hGnpY5d94IZya7erGlbVOPSzVndpbCNknLjrgN+8kRKLRRUR8Hwk+os61LuIdiJS+WTWG9Osx4luQAM/byAA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=QaeMTs0Y; arc=none smtp.client-ip=185.246.85.4 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="QaeMTs0Y" Received: from smtpout-01.galae.net (smtpout-01.galae.net [212.83.139.233]) by smtpout-03.galae.net (Postfix) with ESMTPS id C728D4E414EA; Thu, 3 Sep 2026 08:16:36 +0000 (UTC) Received: from mail.galae.net (mail.galae.net [212.83.136.155]) by smtpout-01.galae.net (Postfix) with ESMTPS id 8C227602B8; Thu, 3 Sep 2026 08:16:36 +0000 (UTC) Received: from [127.0.0.1] (localhost [127.0.0.1]) by localhost (Mailerdaemon) with ESMTPSA id 4259511C79B6F; Thu, 3 Sep 2026 10:16:28 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=dkim; t=1788423391; h=from:subject:date:message-id:to:cc:mime-version:content-type: content-transfer-encoding:in-reply-to:references; bh=YLfdgrdlzJj/pA2hZxsG9Y8cox2mPc65rtCPL4VHF9o=; b=QaeMTs0YKnXkCj5NgrK/CQd21t8R3DVdCU9qx6WjgKS1bKEHNSM++I2MzZI4MJKbrTaxP+ 16ZmiVnbkjmkEPiOWLs5bwMoOxAMF1bwkIwtqyKIbXGuQpk37Ru7JfsJZuv554AhEn1XZ2 EUfoKHh+cAh9PgfqWHbkJ9im/nNtw3fawjw4jwCYpt+rMPICSqwFdTvzelW+jwtMgJWMTz K7JhWC16MA2GhcGwtwBQHF2HlExG0HGlgj03PGIqAGReKEW2yZzk7hkLBO/ErRQHio5Vdu Tyi9aybLxs5VMNO+ppG94q3zUXl3xb+C7SHCpt+m3YGJpkWE6dWrIsQMDNrToA== From: Miquel Raynal To: Santhosh Kumar K Cc: Mark Brown , , , , , , , , , , , , , , , , Subject: Re: [PATCH v9 08/18] spi: cadence-quadspi: add PHY tuning support In-Reply-To: (Santhosh Kumar K.'s message of "Wed, 2 Sep 2026 15:15:24 +0530") References: <20260825171737.776052-1-s-k6@ti.com> <20260825171737.776052-9-s-k6@ti.com> <8aac0c42-fad5-4146-a2a3-b60bdab71a20@sirena.org.uk> User-Agent: mu4e 1.12.12; emacs 30.2 Date: Thu, 03 Sep 2026 10:16:28 +0200 Message-ID: <875x0m7ns3.fsf@bootlin.com> Precedence: bulk X-Mailing-List: linux-spi@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Last-TLS-Session-Version: TLSv1.3 Hi Santhosh, > The DQS bit in CQSPI_REG_READCAPTURE is used for read data capture and > it's not consulted during writes. In the end, how do you know you can expect a DQS signal during reads? Will that work if the chip does not enable it? I still do not understand how this can work. Thanks, Miqu=C3=A8l