----- Forwarded message from bugzilla-daemon@xxxxxxxxxxxxxxxxxxx ----- Date: Wed, 23 Sep 2020 15:22:47 +0000 From: bugzilla-daemon@xxxxxxxxxxxxxxxxxxx To: bjorn@xxxxxxxxxxx Subject: [Bug 209361] New: PTMControl Enabled blocks Low Power Idle in 5% of s2idle attempts - Dell XPS-13 9300 Ice Lake Message-ID: <bug-209361-41252@xxxxxxxxxxxxxxxxxxxxxxxxx/> https://bugzilla.kernel.org/show_bug.cgi?id=209361 Bug ID: 209361 Summary: PTMControl Enabled blocks Low Power Idle in 5% of s2idle attempts - Dell XPS-13 9300 Ice Lake Product: Drivers Version: 2.5 Kernel Version: 5.9-rc5 Hardware: All OS: Linux Tree: Mainline Status: NEW Severity: normal Priority: P1 Component: PCI Assignee: drivers_pci@xxxxxxxxxxxxxxxxxxxx Reporter: lenb@xxxxxxxxxx Regression: No System: Dell XPS-13 9300, Intel(R) Core(TM) i7-1065G7 Up through Linux 5.9-rc5, this system will typically get very good residency in Low-Power-Idle upon s2idle. But on 5% of attempts, it gets ZERO residency in low-power-idle. I have confirmed that this does not change if the time sleeping is extended, or the time between experiments is extended. David Box suggested disabling PTM. Doing so resulted -- for the first time -- the system entering LPI on s2idle 100% of s2idle attempts (770 attempts over 8 hours) ~/bin/pci_write8 0 0x1d 0 0x158 0 ~/bin/pci_write8 0 0x1d 7 0x158 0 is what I used to disable PTM on my system (write a 0, where pci_read8 previously showed the value 3) This change is visible in the output of lspci as for both bridges: < PTMControl: Enabled:+ RootSelected:+ > PTMControl: Enabled:- RootSelected:- -- You are receiving this mail because: You are watching the assignee of the bug. ----- End forwarded message -----
