public inbox for linux-tegra@vger.kernel.org
 help / color / mirror / Atom feed
From: Bjorn Helgaas <helgaas@kernel.org>
To: Vidya Sagar <vidyas@nvidia.com>
Cc: Manikanta Maddireddy <mmaddireddy@nvidia.com>,
	"bhelgaas@google.com" <bhelgaas@google.com>,
	"lpieralisi@kernel.org" <lpieralisi@kernel.org>,
	"kwilczynski@kernel.org" <kwilczynski@kernel.org>,
	"mani@kernel.org" <mani@kernel.org>,
	"robh@kernel.org" <robh@kernel.org>,
	"krzk+dt@kernel.org" <krzk+dt@kernel.org>,
	"conor+dt@kernel.org" <conor+dt@kernel.org>,
	"thierry.reding@gmail.com" <thierry.reding@gmail.com>,
	Jon Hunter <jonathanh@nvidia.com>,
	"kishon@kernel.org" <kishon@kernel.org>,
	"arnd@arndb.de" <arnd@arndb.de>,
	"gregkh@linuxfoundation.org" <gregkh@linuxfoundation.org>,
	"Frank.Li@nxp.com" <Frank.Li@nxp.com>,
	"den@valinux.co.jp" <den@valinux.co.jp>,
	"hongxing.zhu@nxp.com" <hongxing.zhu@nxp.com>,
	"jingoohan1@gmail.com" <jingoohan1@gmail.com>,
	"cassel@kernel.org" <cassel@kernel.org>,
	"18255117159@163.com" <18255117159@163.com>,
	"linux-pci@vger.kernel.org" <linux-pci@vger.kernel.org>,
	"linux-tegra@vger.kernel.org" <linux-tegra@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v6 1/9] PCI: tegra194: Drive CLKREQ signal low explicitly
Date: Mon, 2 Mar 2026 17:34:01 -0600	[thread overview]
Message-ID: <20260302233401.GA4036986@bhelgaas> (raw)
In-Reply-To: <2b1f2d0f-b07d-4b14-ac19-78112ca84f05@nvidia.com>

On Fri, Feb 27, 2026 at 12:35:31PM +0000, Vidya Sagar wrote:
> On 24/02/26 00:15, Manikanta Maddireddy wrote:
> > From: Vidya Sagar <vidyas@nvidia.com>
> > 
> > Currently, the default setting is that CLKREQ signal of a Root Port
> > is internally overridden to '0' to enable REFCLK to flow out to the slot.
> > It is observed that one of the PCIe switches (case in point Broadcom PCIe
> > Gen4 switch) is propagating the CLKREQ signal of the root port to the
> > downstream side of the switch and expecting the endpoints to pull it low
> > so that it (PCIe switch) can give out the REFCLK although the Switch as
> > such doesn't support CLK-PM or ASPM-L1SS. So, as a workaround, this patch
> > drives the CLKREQ of the Root Port itself low to avoid link up issues
> > between PCIe switch downstream port and endpoints. This is not a wrong
> > thing to do after all the CLKREQ is anyway being overridden to '0'
> > internally and now it is just that the same is being propagated outside
> > also.

Inconsistent styling of "Root Port", "root port".  Spec uses
"CLKREQ#".

> > Signed-off-by: Vidya Sagar <vidyas@nvidia.com>
> > Signed-off-by: Manikanta Maddireddy <mmaddireddy@nvidia.com>

> Reviewed-by: Vidya Sagar <vidyas@nvidia.com>

A Reviewed-by tag here seems a little weird since you're the source of
the patch.  I'm not sure what that would mean.

  reply	other threads:[~2026-03-02 23:34 UTC|newest]

Thread overview: 22+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-02-23 18:45 [PATCH v6 0/9] Enhancements to pcie-tegra194 driver Manikanta Maddireddy
2026-02-23 18:45 ` [PATCH v6 1/9] PCI: tegra194: Drive CLKREQ signal low explicitly Manikanta Maddireddy
2026-02-27 12:35   ` Vidya Sagar
2026-03-02 23:34     ` Bjorn Helgaas [this message]
2026-03-03  6:51       ` Manikanta Maddireddy
2026-02-23 18:45 ` [PATCH v6 2/9] PCI: tegra194: Calibrate P2U for endpoint mode Manikanta Maddireddy
2026-02-27 12:35   ` Vidya Sagar
2026-02-23 18:45 ` [PATCH v6 3/9] PCI: tegra194: Remove IRQF_ONESHOT flag during Endpoint interrupt registration Manikanta Maddireddy
2026-02-27 12:35   ` Vidya Sagar
2026-02-23 18:45 ` [PATCH v6 4/9] PCI: tegra194: Enable DMA interrupt Manikanta Maddireddy
2026-02-27 12:36   ` Vidya Sagar
2026-02-23 18:45 ` [PATCH v6 5/9] PCI: tegra194: Enable hardware hot reset mode in Endpoint Manikanta Maddireddy
2026-02-27 12:36   ` Vidya Sagar
2026-02-23 18:45 ` [PATCH v6 6/9] PCI: tegra194: Disable L1.2 capability of Tegra234 EP Manikanta Maddireddy
2026-02-27 12:36   ` Vidya Sagar
2026-02-23 18:45 ` [PATCH v6 7/9] dt-bindings: PCI: tegra194: Add monitor clock support Manikanta Maddireddy
2026-02-27 12:36   ` Vidya Sagar
2026-02-23 18:45 ` [PATCH v6 8/9] PCI: tegra194: Add core " Manikanta Maddireddy
2026-02-27 12:36   ` Vidya Sagar
2026-02-23 18:45 ` [PATCH v6 9/9] PCI: tegra194: Add ASPM L1 entrance latency config Manikanta Maddireddy
2026-02-27 12:36   ` Vidya Sagar
2026-02-27 16:59 ` [PATCH v6 0/9] Enhancements to pcie-tegra194 driver Jon Hunter

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=20260302233401.GA4036986@bhelgaas \
    --to=helgaas@kernel.org \
    --cc=18255117159@163.com \
    --cc=Frank.Li@nxp.com \
    --cc=arnd@arndb.de \
    --cc=bhelgaas@google.com \
    --cc=cassel@kernel.org \
    --cc=conor+dt@kernel.org \
    --cc=den@valinux.co.jp \
    --cc=gregkh@linuxfoundation.org \
    --cc=hongxing.zhu@nxp.com \
    --cc=jingoohan1@gmail.com \
    --cc=jonathanh@nvidia.com \
    --cc=kishon@kernel.org \
    --cc=krzk+dt@kernel.org \
    --cc=kwilczynski@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-pci@vger.kernel.org \
    --cc=linux-tegra@vger.kernel.org \
    --cc=lpieralisi@kernel.org \
    --cc=mani@kernel.org \
    --cc=mmaddireddy@nvidia.com \
    --cc=robh@kernel.org \
    --cc=thierry.reding@gmail.com \
    --cc=vidyas@nvidia.com \
    /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