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From:   "Nitin Rawat (QUIC)" <quic_nitirawa@quicinc.com>
To:     Christoph Hellwig <hch@infradead.org>,
        Vidya Sagar <vidyas@nvidia.com>,
        Keith Busch <kbusch@kernel.org>,
        "rjw@rjwysocki.net" <rjw@rjwysocki.net>
CC:     Keith Busch <kbusch@kernel.org>, Jens Axboe <axboe@fb.com>,
        Sagi Grimberg <sagi@grimberg.me>,
        "linux-nvme@lists.infradead.org" <linux-nvme@lists.infradead.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "Sajida Bhanu (Temp) (QUIC)" <quic_c_sbhanu@quicinc.com>
Subject: RE: [PATCH v3] nvme/pci: Add quick suspend quirk for Sc7280 Platform
Thread-Topic: [PATCH v3] nvme/pci: Add quick suspend quirk for Sc7280 Platform
Thread-Index: AQHYHsBOpLTvLkaTP0STBN0OK3zww6yOaCmAgAfvxCCAAAk1EA==
Date:   Wed, 16 Feb 2022 16:09:03 +0000
Message-ID: <fe6f99c47e2546429311d090999cd9df@quicinc.com>
References: <1644526408-10834-1-git-send-email-quic_nitirawa@quicinc.com>
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Hi Christoph/Keith/Rafael

Since we are giving control to PCIe (NVMe power rails control), it can vary=
 from platform to platform.
More over, PCIe driver doesn't control these power rails directly from PCIe=
 driver, they tie nvme supply with one of the pcie supply and control them =
together.=20
So i think it would be better to either have quirk based on platform or alw=
ays setting simple suspend and platform which needs full suspend can update=
 it through some means.=20

Based on below link, Looks like this can be across platform ...vidya also m=
ention similar concern for tegra platform. =20
https://lore.kernel.org/lkml/20220209202639.GB1616420@dhcp-10-100-145-180.w=
dc.com/T/#md10b0108b3ccbb1254fe0ad8dbb6e98044a8820b

Please let me know your opinions.

Thanks,
Nitin
-----Original Message-----
From: Christoph Hellwig <hch@infradead.org>
Sent: Friday, February 11, 2022 11:53 AM
To: Nitin Rawat (QUIC) <quic_nitirawa@quicinc.com>
Cc: Keith Busch <kbusch@kernel.org>; Jens Axboe <axboe@fb.com>; Sagi Grimbe=
rg <sagi@grimberg.me>; linux-nvme@lists.infradead.org; linux-kernel@vger.ke=
rnel.org; Sajida Bhanu (Temp) (QUIC) <quic_c_sbhanu@quicinc.com>
Subject: Re: [PATCH v3] nvme/pci: Add quick suspend quirk for Sc7280 Platfo=
rm

On Fri, Feb 11, 2022 at 02:23:28AM +0530, Nitin Rawat wrote:
> Enable quick suspend quirks for Sc7280 platform, where power to nvme=20
> device is removed during suspend-resume process. This is done to avoid=20
> the failure dring resume.

You need to sort this out in the PCI and PM layers.  The broken platform wi=
ll also affect all other PCIe drivers and not just nvme.