NACK Re: [SRU] [OEM-B] [PULL] Add Runtime D3 and ASPM support for r8169

[Timo Aaltonen]

On 26.06.2018 17:54, Kai-Heng Feng wrote:
> BugLink: https://bugs.launchpad.net/bugs/1757422
> 
> [Impact]
> r8169 stays in D0 even when no ethernet cable is plugged in. This drains
> lots of power (~3W). The tested laptop uses 5.5W when r8169 is in D0,
> 1.8W when r8169 is in D3. The power saved is substantial.
> 
> [Fix]
> Improved rumtime PM logic to let the device gets suspended (D3) when the
> port is not in used and the link is down.
> 
> Sync r8169 driver with linux-next. So in addition to D3, we have proper
> ASPM support now.
> 
> All commits are cleanly cherry-picked.
> This means the fix for LP: #1752772 is dropped and re-cherry-picked.
> 
> [Test Case]
> The chip version is 8168h/8111h.
> Test when no ethernet gets plugged.
> 
> Powertop shows power consumption is roughly 5.5W.
> lspci shows the device is in D0.
> 
> With the patch,
> The power consumption is reduced to 1.8W.
> lspci shows the device is in D3, PME# is correctly enabled.
> Plug ethernet cable can corretly wake up the device.
> Unplug the cable, the device gets suspended to D3 correctly.
> 
> [Regression Potential]
> Medium. The change set is massive although it's limited to r8169.
> It should still be fine because OEM-B is the only user and we have QA as
> our safety net.


So, since we don't know yet which kernel will eventually replace 4.15
based OEM-B kernel, and since upgrades from xenial oem -> bionic
backport need a DKMS anyway, we've decided that this backport won't get
applied to OEM-B. Applying it to OEM-B would essentially mean that users
could not be migrated to bionic master, because this backport is too big
for it.


-- 
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