On Thu, Jun 02, 2016 at 11:17:10AM +0300, Mika Westerberg wrote: > Current Linux PCI core does not do any kind of power management to PCIe > ports. This means that we waste energy and consume laptop battery even if > the port has nothing connected to. These patches aim to change that to the > right direction. > > Previous versions of the patches can be found below: > > v1: http://www.spinics.net/lists/linux-pci/msg49313.html > v2: http://www.spinics.net/lists/linux-pci/msg50167.html > v3: http://www.spinics.net/lists/linux-pci/msg50345.html > v4: http://www.spinics.net/lists/linux-pci/msg50665.html > v5: http://www.spinics.net/lists/linux-pci/msg50803.html > > This assumes that recent (starting from 2015) PCIe ports are capable of > transition to D3hot/D3cold. We add a new flag to struct pci_dev 'bridge_d3' > that is set whenever the PCI core thinks the port can be put to D3. The > check in pci_pm_suspend_noirq() is then extended to cover devices where > 'bridge_d3' is set. > > We then add two new functions pci_bridge_d3_device_changed/removed(). These > are used to set and clear 'bridge_d3' whenever there is a change in device > power management policy (or if the device is removed). For example when > userspace forbids the device to enter D3cold pci_bridge_d3_device_changed() > will clear 'bridge_d3' of the upstream bridge. > > For all PCI ports where 'bridge_d3' is set we also enable and unblock > runtime PM automatically. Only exception is when the PCIe port claims to > support hotplug. More information about that is in the changelog of > patch [5/5]. > > Since this also touches xhci, I'm adding Mathias and Greg to check if the > change looks reasonable. > > Bjorn, if you are fine with these patches, it would be nice to get these to > linux-next for better testing coverage. Applied to pci/pm with Rafael's additional acks, thanks, Mika! -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
