Date: Mon, 02 May 2016 14:44:13 +0000 From: bugzilla-noreply@freebsd.org To: freebsd-bugs@FreeBSD.org Subject: [Bug 209202] [PATCH] [powermac_thermal] In-Kernel PowerMac fan control does not effectively regular some quad core models Message-ID: <bug-209202-8@https.bugs.freebsd.org/bugzilla/>
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https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D209202 Bug ID: 209202 Summary: [PATCH] [powermac_thermal] In-Kernel PowerMac fan control does not effectively regular some quad core models Product: Base System Version: 11.0-CURRENT Hardware: ppc OS: Any Status: New Keywords: patch Severity: Affects Some People Priority: --- Component: kern Assignee: freebsd-bugs@FreeBSD.org Reporter: gmbroome@vcu.edu Keywords: patch Created attachment 169882 --> https://bugs.freebsd.org/bugzilla/attachment.cgi?id=3D169882&action= =3Dedit Patch to add additional temp level and longer hysteresis to PowerMac thermal management The in-kernel fan control for PowerMac systems works reasonably well for single- and dual-core systems, but has mixed results for quad-core systems based on the system condition and CPU assembly revision. For "revision 1" CPU assemblies (one shared radiator and pump) in quad-core PowerMac G5 units, the system runs extremely hot, hitting critical temperat= ure and forcibly shutting down during even moderate CPU utilization. For "revision 2" CPU assemblies (a discrete radiator and pump for each CPU package), the fans run at high baseline levels, though the system does not typically reach critical temperature or forcibly shut down. The attached patch, which includes changes to powermac_thermal.[c|h], smu.c, and smusat.c, adds an intermediate temperature target above which fans and pumps run at full speed, but which is still well below the critical tempera= ture that forces a shutdown. In testing, this leaves the "revision 1" quad-core systems usable, albeit noisy. Quad-core systems using the "revision 2" CPU assembly scale fan and pump speed more aggressively, but run them at lower levels during idling. = The dual-core system tested remained largely unaffected by the changes. The pa= tch is not expected to affect anything but the last generation of PowerMac mode= ls, i.e. only ones with an SMU. --=20 You are receiving this mail because: You are the assignee for the bug.=
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