From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bmailout2.hostsharing.net (bmailout2.hostsharing.net [83.223.78.240]) (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 E3F08217F55; Mon, 10 Nov 2025 12:41:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=83.223.78.240 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762778517; cv=none; b=MFaIKwZi4G9dM6Zv0bffcnKq/8YGJuniu0px6/xdtvU3ozJbcHozcVLrAsl5eErLTaFRyvd4Z2MsO0BzJ5WJOS9IWkc57hrA7wg7no+Jg3bEgFmDNImT4wD3iDCoIQ4Xb655yG1SVdqWNcyoC/z/2IlD8VUxhYLK9MeOIQrul50= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762778517; c=relaxed/simple; bh=rOEMtbbUyW+Eslmgmwt2fk+00r5/HDm24f1e/jESj+g=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=T4yUb+/2zevFDaRzeWFfRChAC7Jl6z/TM59jZXNXgCCHeCiM03Vyc0ovbeIO9f1ZGPDMGPP3m9aLFLum8TUUyrq7ugcO8rkur8f28au+EWokdHqeHK41EHRgNGgNfody/SW0rCQRtzGwO9eRnBUJfSYp+wJH5SmQe3lFAosOEtQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=wunner.de; spf=none smtp.mailfrom=h08.hostsharing.net; arc=none smtp.client-ip=83.223.78.240 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=wunner.de Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=h08.hostsharing.net Received: from h08.hostsharing.net (h08.hostsharing.net [83.223.95.28]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature ECDSA (secp384r1) client-digest SHA384) (Client CN "*.hostsharing.net", Issuer "GlobalSign GCC R6 AlphaSSL CA 2025" (verified OK)) by bmailout2.hostsharing.net (Postfix) with ESMTPS id D7E642009199; Mon, 10 Nov 2025 13:41:45 +0100 (CET) Received: by h08.hostsharing.net (Postfix, from userid 100393) id C3CCB15C2; Mon, 10 Nov 2025 13:41:45 +0100 (CET) Date: Mon, 10 Nov 2025 13:41:45 +0100 From: Lukas Wunner To: Krishna Chaitanya Chundru Cc: andersson@kernel.org, robh@kernel.org, manivannan.sadhasivam@linaro.org, krzk@kernel.org, helgaas@kernel.org, linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org, lpieralisi@kernel.org, kw@linux.com, conor+dt@kernel.org, linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree-spec@vger.kernel.org, quic_vbadigan@quicinc.com Subject: Re: [PATCH v2] schemas: pci: Document PCIe T_POWER_ON Message-ID: References: <20251110112947.2071036-1-krishna.chundru@oss.qualcomm.com> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20251110112947.2071036-1-krishna.chundru@oss.qualcomm.com> On Mon, Nov 10, 2025 at 04:59:47PM +0530, Krishna Chaitanya Chundru wrote: > From PCIe r6, sec 5.5.4 & Table 5-11 in sec 5.5.5 T_POWER_ON is the Please use the latest spec version as reference, i.e. PCIe r7.0. > minimum amount of time(in us) that each component must wait in L1.2.Exit > after sampling CLKREQ# asserted before actively driving the interface to > ensure no device is ever actively driving into an unpowered component and > these values are based on the components and AC coupling capacitors used > in the connection linking the two components. > > This property should be used to indicate the T_POWER_ON for each Root Port. What's the difference between this property and the Port T_POWER_ON_Scale and T_POWER_ON_Value in the L1 PM Substates Capabilities Register? Why do you need this in the device tree even though it's available in the register? Thanks, Lukas