APPLIED(B,C)/cmnt: [PATCH 0/2][SRU][B][OEM-B] Power consumption during s2idle is higher than long idle(sk hynix)

[AceLan Kao]

BTW, my patches use a function, pm_suspend_via_s2idle(),
from below commit which seems doesn't be applied to bionic/cosmic yet.
I've give it one ack, please consider apply this commit before mine.
Thanks

https://lists.ubuntu.com/archives/kernel-team/2018-October/096141.html
AceLan Kao <acelan.kao at canonical.com> 於 2018年11月8日 週四 下午4:32寫道：
>
> Yes, these commits should apply to bionic-oem, too.
> I think bionic-oem will rebase on generic kernel, so I didn't specify
> bionic-oem explicitly.
> Khaled Elmously <khalid.elmously at canonical.com> 於 2018年11月8日 週四 下午1:06寫道：
> >
> > Does this need to be applied to bionic-oem specifically? It's been applied only to bionic/master-next (and cosmic/master-next).
> >
> >
> > On 2018-11-06 18:53:10 , AceLan Kao wrote:
> > > BugLink: https://bugs.launchpad.net/bugs/1801875
> > >
> > > [Impact]
> > > On some Dell XPS models, we observed the power consumption raises higher
> > > than long idle does during s2idle with sk hynix nvme.
> > >
> > > C2:
> > > Short idle: 4
> > > Long idle: 1
> > > S2I: 3.7
> > > S5: 0.19
> > >
> > > C3:
> > > Short idle: 7.2
> > > Long idle: 4.5
> > > S2I: 6.22
> > > S5: 0.18
> > >
> > > C5:
> > > Short idle: 6.5
> > > Long idle: 1
> > > S2I: 2.88
> > > S5: 0.18
> > >
> > > [Fix]
> > > From SK hynix FE, MS Windows doesn't put nvme to D3, and uses its own
> > > APST feature to do the power management. To leverage its APST feature
> > > during s2idle, we can't disable nvme device while suspending, too.
> > > So, here is what we did on the driver, 1. prevent nvme from entering
> > > D3, 2. prevent nvme from being disabled when suspending.
> > >
> > > [Test]
> > > Verified on different XPS machines with different sk hynix nvme disks,
> > > it fixes the power consumption issue with no regression. And the power
> > > consumption drops to 0.77W during s2idle.
> > >
> > > [Regression Potential]
> > > Low, the patches only applied to specific nvme module, and from our
> > > test, the system is still stable.
> > >
> > > [Misc]
> > > This issue should be fixed by the firmware, and we're pushing sk hynix
> > > to fix it. But before sk hynix find out how to solve it, we have to
> > > preserve these commits in our kernel for a while.
> > > BTW, the patches require pm_suspend_via_s2idle() function from below
> > > commit which is still under reviewing.
> > > https://lists.ubuntu.com/archives/kernel-team/2018-October/096141.html
> > >
> > > AceLan Kao (2):
> > >   pci: prevent sk hynix nvme from entering D3
> > >   nvme: add quirk to not call disable function when suspending
> > >
> > >  drivers/nvme/host/nvme.h | 5 +++++
> > >  drivers/nvme/host/pci.c  | 8 +++++++-
> > >  drivers/pci/quirks.c     | 1 +
> > >  include/linux/pci_ids.h  | 2 ++
> > >  4 files changed, 15 insertions(+), 1 deletion(-)
> > >
> > > --
> > > 2.17.1
> > >
> > >
> > > --
> > > kernel-team mailing list
> > > kernel-team at lists.ubuntu.com
> > > https://lists.ubuntu.com/mailman/listinfo/kernel-team