Hi, The BIOS fix was actually just an initial workaround - the proper fix is the kernel patch (https://patchwork.freedesktop.org/patch/338599/?series=68817&rev=4 )which went into 5.4-rc8 and has also been backported into Debian sid at the end of last year
To add some context/detail in case it helps or is of interest: We found the issue and worked with Intel - in summary the wrong clock was used on resume and it meant, for OLED panels, not enough time was allowed for initialization/training to complete and this sometimes leads to a black screen (ssh etc still works). The BIOS fix was to increase the timeout (from the spec version of 200ms to 210ms I believe) but it's just a workaround. We released it as we had some customers who needed the fix quickly and we were worried it would take a long time for the patch to upstream and then to get into the distros. Releasing a new BIOS isn't a fast process and as it turned out the kernel patch went through really fast (doesn't always happen 😊) so we probably could have skipped the BIOS workaround, but the tweak is minor and safe so it's good to have it available for those needing to use an older kernel. Summary: If you're running a newer kernel than 5.4-rc8 and don't care about the enhancements in the update you don't need to update the BIOS for the timing fix. Let me know if any questions. Mark > -----Original Message----- > From: Jiri Kanicky <[email protected]> > Sent: Sunday, January 26, 2020 11:48 PM > To: [email protected] > Subject: Bug#944350: RE: Bug#944350: RE: [External] Bug#944350: systemd: > screen remains off after waking up from suspend > > FYI Lenovo also pushed a fix into a BIOS. > > CHANGES IN THIS RELEASE > Version 1.28 > > [Important updates] > Nothing > > [New functions or enhancements] > - Supported BIOS password authentication before entering into MEBx. > - Updated Regulatory Information. > > [Problem fixes] > - Fixed an issue where OLED panel might not trun on after resuming from > sleep on Linux. > > https://download.lenovo.com/pccbbs/mobiles/n2oul07w.txt > > > > > > Regards, Jiri > > > > > > On Fri, 6 Dec 2019 18:47:05 +0000 Mark Pearson <[email protected]> > <mailto:[email protected]> wrote: > > > Hi Jiri, > > > > I'm pretty sure it's not in 5.3.0-2. Are you sure? I can look again but I > recently did put in a merge request to get it pulled into sid: > https://salsa.debian.org/kernel-team/linux/merge_requests/188 > > > > Not sure if/when it will be accepted (it's only my 2nd attempt at doing > > this) > but hopefully someone looks at it and thinks it's useful) > > > > Mark > > > > > -----Original Message----- > > > From: Jiri Kanicky <[email protected]> <mailto:[email protected]> > > > Sent: Saturday, November 30, 2019 6:56 AM > > > To: [email protected] <mailto:[email protected]> > > > Subject: Bug#944350: RE: [External] Bug#944350: systemd: screen > remains > > > off after waking up from suspend > > > > > > Hi. > > > > > > It seems that Debian 5.3.0-2-amd64 includes the code in the patch > > > already and I still have the issue. > > > > > > Jiri > > > > > > On Mon, 25 Nov 2019 16:45:55 +0000 Mark Pearson > > > <[email protected]> <mailto:[email protected]> wrote: > > > > > > > Hi, > > > > > > > > I don't know if this is helpful but I recently debugged a similar > > > issue on the Lenovo P1Gen2. There the problem is only with the > > > integrated graphics and an OLED screen - we tracked it down to an issue > > > in the i915 driver where it wasn't giving enough time for eDP link > > > training. It turned out this was due to the driver using the wrong > > > clocks after a suspend and resume . > > > > > > > > Intel recently up-streamed a fix (commit 2f216a85 - it went into > > > 5.4-rc8) > > > > > > > > I'm working on doing a patch that I'm hoping to get into Debian to > > > backport - just not done yet :) The patch is pretty small (I've attached > > > it) so you might want to give it a go and see if it helps. > > > > > > > > Note - we did also test X1 extreme with OLED panel and didn't see a > > > problem there....but it's a really subtle timing issue so some units > > > might be more susceptible than others. Maybe worth a go? > > > > > > > > If it does make a difference let me know. > > > > Mark > > > > > > >
