在 2021/11/1 下午5:18, Mathias Nyman 写道:
Hi
On 1.11.2021 9.17, Yinbo Zhu wrote:
After S5, any pci device should into D3 state that if supported, but the
uPD720201 was not and it may be the cause of xhci firmware and cause
OSPM power consumption is more higher that S5 than S4. I think xhci HCD
can add a quirk ensure it into D3 state after S5 that is appropriate
and this patch was to add LPM quirk and set PCI_D3hot to uPD720201 pmsc
register in xhci_pci_shutdown to fix xhci power consumption issue.
Signed-off-by: Yinbo Zhu <zhuyinbo@xxxxxxxxxxx>
I think we need a better understanding of the underlying issue before
adding a quirk like this.
Is this a known issue with the uPD720201 controller firmware? or is it
an issue with ACPI table entries not supporting the proper D state in BIOS
on the tested platform, or something completely different?
Yes, and I notice other xhci hc doesn't encounter this power consumption
issue I think that xhci firmware
may be set D3 after s5, but the xhci firmware code isn't visible, in
addition I find that test platform the
_PS3 method wasn't implemented in acpi table which can make device into
S3, Bios team didn't add it for
some platform reason and I think xhci hcd to ensure device into D3 state
after s5 that is appropriate
Also, LPM usually refers to "Link Power Management" in the xHCI spec.
This is about the U1 and U2 link states for the connected USB device.
If we end up needing a new xhci quirk it will need a new name.
Thanks
-Mathias
Hi Mathias,
I had changed the quirk that replace XHCI_LPM_QUIRK with XHCI_LWP_QUIRK
as v2 version patch.
please view the v2 version patch.
Thanks,
Yinbo.
