From: Bjorn Helgaas <helgaas@kernel.org>
To: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Cc: bhelgaas@google.com, lorenzo.pieralisi@arm.com,
kbusch@kernel.org, hch@lst.de, linux-nvme@lists.infradead.org,
linux-pci@vger.kernel.org, linux-arm-msm@vger.kernel.org,
linux-kernel@vger.kernel.org, svarbanov@mm-sol.com,
bjorn.andersson@linaro.org, axboe@fb.com,
quic_vbadigan@quicinc.com, quic_krichai@quicinc.com,
quic_nitirawa@quicinc.com, vidyas@nvidia.com, sagi@grimberg.me
Subject: Re: [PATCH 1/3] PCI: Add a flag to notify PCI drivers about powerdown during suspend
Date: Mon, 16 May 2022 15:18:17 -0500 [thread overview]
Message-ID: <20220516201817.GA1047280@bhelgaas> (raw)
In-Reply-To: <20220513110027.31015-2-manivannan.sadhasivam@linaro.org>
On Fri, May 13, 2022 at 04:30:25PM +0530, Manivannan Sadhasivam wrote:
> On some systems like Chromebooks based on Qcom chipsets, the OS may
> powerdown all PCIe devices during system suspend for aggressive
> powersaving. In that case, the PCI host controller drivers need to notify
> the PCI device drivers that the power will be taken off during system
> suspend so that the drivers can prepare the devices accordingly.
"The OS may powerdown all PCIe devices ..." makes it sound like this
is an OS policy decision. Where exactly (what function) is that?
Or if it's not an OS policy decision, but rather some property of the
hardware, say that specifically.
> One prime example is the PCI NVMe driver. This flag can be used by the
> driver to shutdown the NVMe device during suspend and recover it during
> resume.
>
> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> ---
> include/linux/pci.h | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/include/linux/pci.h b/include/linux/pci.h
> index 60adf42460ab..069caf1fe88d 100644
> --- a/include/linux/pci.h
> +++ b/include/linux/pci.h
> @@ -578,6 +578,7 @@ struct pci_host_bridge {
> unsigned int preserve_config:1; /* Preserve FW resource setup */
> unsigned int size_windows:1; /* Enable root bus sizing */
> unsigned int msi_domain:1; /* Bridge wants MSI domain */
> + unsigned int suspend_poweroff:1; /* OS may poweroff devices during system suspend */
>
> /* Resource alignment requirements */
> resource_size_t (*align_resource)(struct pci_dev *dev,
> --
> 2.25.1
>
next prev parent reply other threads:[~2022-05-16 20:39 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-05-13 11:00 [PATCH 0/3] PCI: Notify PCI drivers about powerdown during suspend Manivannan Sadhasivam
2022-05-13 11:00 ` [PATCH 1/3] PCI: Add a flag to notify " Manivannan Sadhasivam
2022-05-16 20:18 ` Bjorn Helgaas [this message]
2022-05-17 15:09 ` Manivannan Sadhasivam
2022-05-17 17:24 ` Bjorn Helgaas
2022-05-18 3:59 ` Manivannan Sadhasivam
2022-05-26 20:48 ` Rob Herring
2022-05-13 11:00 ` [PATCH 2/3] PCI: dwc: qcom: Set suspend_poweroff flag for SC7280 Manivannan Sadhasivam
2022-05-16 20:19 ` Bjorn Helgaas
2022-05-17 15:11 ` Manivannan Sadhasivam
2022-05-17 17:18 ` Bjorn Helgaas
2022-05-18 3:52 ` Manivannan Sadhasivam
2022-05-18 16:50 ` Bjorn Helgaas
2022-05-18 8:43 ` Christoph Hellwig
2022-05-13 11:00 ` [PATCH 3/3] nvme-pci: Make use of "suspend_poweroff" flag during system suspend Manivannan Sadhasivam
2022-05-16 5:44 ` [PATCH 0/3] PCI: Notify PCI drivers about powerdown during suspend Christoph Hellwig
2022-05-16 20:15 ` Bjorn Helgaas
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=20220516201817.GA1047280@bhelgaas \
--to=helgaas@kernel.org \
--cc=axboe@fb.com \
--cc=bhelgaas@google.com \
--cc=bjorn.andersson@linaro.org \
--cc=hch@lst.de \
--cc=kbusch@kernel.org \
--cc=linux-arm-msm@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-nvme@lists.infradead.org \
--cc=linux-pci@vger.kernel.org \
--cc=lorenzo.pieralisi@arm.com \
--cc=manivannan.sadhasivam@linaro.org \
--cc=quic_krichai@quicinc.com \
--cc=quic_nitirawa@quicinc.com \
--cc=quic_vbadigan@quicinc.com \
--cc=sagi@grimberg.me \
--cc=svarbanov@mm-sol.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;
as well as URLs for NNTP newsgroup(s).