<html> <head> <base href="https://bugs.freedesktop.org/"> </head> <body> <div> <a class="bz_bug_link bz_status_ASSIGNED " title="ASSIGNED - Acer Aspire V7-582PG (Haswell, GTX 750M) fails to power off GPU with runtime PM" href="https://bugs.freedesktop.org/show_bug.cgi?id=98398#c13">Comment # 13</a> on <a class="bz_bug_link bz_status_ASSIGNED " title="ASSIGNED - Acer Aspire V7-582PG (Haswell, GTX 750M) fails to power off GPU with runtime PM" href="https://bugs.freedesktop.org/show_bug.cgi?id=98398">bug 98398</a> from <a class="email" href="mailto:peter@lekensteyn.nl" title="Peter Wu <peter@lekensteyn.nl>"> Peter Wu</a> <pre>Created <a href="attachment.cgi?id=127942" name="attach_127942" title="Disable d3cold on bridge when falling back to _DSM">attachment 127942</a> <a href="attachment.cgi?id=127942&action=edit" title="Disable d3cold on bridge when falling back to _DSM">[details]</a> <a href='page.cgi?id=splinter.html&bug=98398&attachment=127942'>[review]</a> Disable d3cold on bridge when falling back to _DSM The workaround patch has been merged in v4.9-rc3-34-gb0a6af8 (and backported to 4.8.7 via v4.8.6-109-g7290da4) but apparently it broke (system?) suspend/resume according to the reporter. Before the workaround patch: - _PR3 method is found, so nouveau assumes that PCI core takes care of D3cold. - Due to an ACPICA bug, PCI core fails to power off the device via runtime PM: <a href="https://bugs.acpica.org/show_bug.cgi?id=1333">https://bugs.acpica.org/show_bug.cgi?id=1333</a> After the workaround patch I guess that this happens: - _PR3 method is found, but unusable. Nouveau falls back to _DSM. - Due to the above ACPICA bug, the power resources not owned by any device. I guess that Linux then decides to power off the "unnecessary" power resource after system resume. (I saw something like this in a dmesg for a similiar SSDT) - At this point I would guess that nouveau then follows the old DSM method, but then I am confused because pcie_port_pm=off (or pre-4.8 kernels) supposedly have the same issue with this power resource. If pcie_port_pm=off helps, then the attached patch should also work (no pcie_port_pm=off needed). Can you give it a try on top of v4.8.7?</pre> </div> <hr> You are receiving this mail because: <ul> <li>You are the assignee for the bug.</li> </ul> </body> </html>