devicetree-spec.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Lukas Wunner <lukas@wunner.de>
To: Krishna Chaitanya Chundru <krishna.chundru@oss.qualcomm.com>
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
Date: Mon, 10 Nov 2025 13:41:45 +0100	[thread overview]
Message-ID: <aRHdiYYcn2uZkLor@wunner.de> (raw)
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

  parent reply	other threads:[~2025-11-10 12:41 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-11-10 11:29 [PATCH v2] schemas: pci: Document PCIe T_POWER_ON Krishna Chaitanya Chundru
2025-11-10 12:03 ` Manivannan Sadhasivam
2025-11-13  7:48   ` Krishna Chaitanya Chundru
2025-11-10 12:41 ` Lukas Wunner [this message]
2025-11-13  4:03   ` Krishna Chaitanya Chundru
2025-11-13  8:36     ` Lukas Wunner
2025-11-13 15:54       ` Bjorn Helgaas
2025-11-13 16:41       ` Manivannan Sadhasivam
2025-11-14  1:02         ` Shawn Lin
2025-11-13  4:31   ` Manivannan Sadhasivam
2025-11-13  5:16     ` Anand Moon
2025-11-13  5:50       ` Manivannan Sadhasivam
2025-11-13  6:16         ` Anand Moon

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=aRHdiYYcn2uZkLor@wunner.de \
    --to=lukas@wunner.de \
    --cc=andersson@kernel.org \
    --cc=conor+dt@kernel.org \
    --cc=devicetree-spec@vger.kernel.org \
    --cc=devicetree@vger.kernel.org \
    --cc=helgaas@kernel.org \
    --cc=krishna.chundru@oss.qualcomm.com \
    --cc=krzk@kernel.org \
    --cc=kw@linux.com \
    --cc=linux-arm-msm@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=lpieralisi@kernel.org \
    --cc=manivannan.sadhasivam@linaro.org \
    --cc=quic_vbadigan@quicinc.com \
    --cc=robh@kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).