From ddf68901f7640aa3789e2c04159804142ca26812 Mon Sep 17 00:00:00 2001 From: Duncan Laurie Date: Fri, 28 Jun 2013 15:59:19 -0700 Subject: peppy: Enable power limiting for thermal control Limit power to 12W at 73C and remove limit at 68C. To have the CPU consume maximum power it is necessary to stress both the CPU and the GPU. Bastion (chrome.supergiantgames.com) and/or webglsamples.googlecode.com can be useful for this. Testing this properly requires a script to report the running average power readings. The watch_power.sh script is attached to this issue in the partner tracker. 1) Run watch_power.sh continuously: localhost ~ # watch -n 0 bash -e /tmp/watch_power.sh 2) Start Bastion (or other stress apps). The power draw should be close to 15W if under enough load. 3) Watch until temperature climbs above 73C and is caught by the thermal zone 10 second poll, this can be sped up by blocking or removing the fan. 4) The ACPI thermal zone states should change to reflect that active[2] is now enabled and power consumption should drop to 12W. 5) Stop the stress apps and wait until the CPU cools off again, enable the fan again if it was removed. 6) The ACPI thermal zone state should switch back to active[3]. Change-Id: Ie6714a8543d4f06edf8513086fc9c968273bdb23 Signed-off-by: Duncan Laurie Reviewed-on: https://gerrit.chromium.org/gerrit/60545 Reviewed-on: http://review.coreboot.org/4335 Tested-by: build bot (Jenkins) Reviewed-by: Alexandru Gagniuc --- src/mainboard/google/peppy/acpi/thermal.asl | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) (limited to 'src/mainboard/google/peppy/acpi') diff --git a/src/mainboard/google/peppy/acpi/thermal.asl b/src/mainboard/google/peppy/acpi/thermal.asl index 69b6ac9834..67f83ef142 100644 --- a/src/mainboard/google/peppy/acpi/thermal.asl +++ b/src/mainboard/google/peppy/acpi/thermal.asl @@ -126,12 +126,18 @@ Scope (\_TZ) } Method (_ON) { Store (0, \FLVL) - \_SB.PCI0.MCHC.STND () + + /* Enable Power Limit */ + \_SB.PCI0.MCHC.CTLE (\F0PW) + Notify (\_TZ.THRM, 0x81) } Method (_OFF) { Store (1, \FLVL) - \_SB.PCI0.MCHC.STDN () + + /* Disable Power Limit */ + \_SB.PCI0.MCHC.CTLD () + Notify (\_TZ.THRM, 0x81) } } -- cgit v1.2.3