Messages in this thread | | | Subject | Re: [PATCH] pm_qos: Add QoS param, minimum system bus frequency | From | Daniel Walker <> | Date | Mon, 04 Jan 2010 14:00:45 -0800 |
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On Mon, 2010-01-04 at 13:38 -0800, mark gross wrote: > On Thu, Dec 31, 2009 at 05:20:27PM -0800, Daniel Walker wrote: > > From: Praveen Chidambaram <pchidamb@quicinc.com> > > > > In some systems, the system bus speed can be varied, usually > > based on the current CPU frequency. However, various device > > drivers and/or applications may need a faster system bus for I/O > > even though the CPU itself may be idle > > What happened to the discussion around multiple platforms needing > multiple bus pm_qos_requirements? > > Is system bus freq too generic? (I'm worried about the name space) > Is this ok? (I'm asking linux-pm for input here.) > On X86 would this be analogous to FSB, Memory, or PCI bus frequencies? > What will happen when there are two buses each wanting a PM_QOS > parameter? Is that a likely scenario?
We can always change the naming in the future, but someone could add a PM_QOS_MEMORY_BUS_FREQ or PM_QOS_PERIPHERAL_BUS_FREQ in addition to this one.. Since it's all generic code having generic naming seems fine..
> Also, on your platform you have a throttling driver controlling the > frequency of some bus, that will use this value as a constraint on how > far it will throttle. no? I would be interested in seeing this driver > sometime. (I just want to make sure no one bastardizes pm_qos into an > operating point thing. I'm not sure I can justify why but I want to > avoid that.)
When you say "operating point thing" do you mean you don't want the frequency adjusted at runtime? You want it set once then move on?
Daniel
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