On Mon, Sep 10, 2012 at 9:07 PM, Alan Cox alan@lxorguk.ukuu.org.uk wrote:
On Mon, 10 Sep 2012 14:31:52 +1000 Dave Airlie airlied@gmail.com wrote:
From: Dave Airlie airlied@redhat.com
For secondary GPUs in laptops, i.e. optimus or powerxpress, we have methods for powering down the GPU completely. This adds support to the drm core for powering back up the GPU on any access from ioctls or sysfs interfaces, and fires a 5s timer to test if we can power the GPU off.
Is there a reason for basically re-inventing the existing Linux dynamic power management layer ?
Not really, wanted to have something simple to demo first. This
"bus type drivers of the buses the devices are on are responsible for the actual handling of the autosuspend requests and wake-up events."
seemed to imply there was some magic in the PCI bus layer that is generic, and in this case that doesn't exist.
We have a 3 specific ACPI calls to power off the GPU slot for nvidia, radeon and apple.
Dave.