[linux-pm] cpuidle future and improvements
daniel.lezcano at linaro.org
Mon Jun 25 13:10:57 UTC 2012
On 06/25/2012 02:58 PM, Shilimkar, Santosh wrote:
> On Mon, Jun 18, 2012 at 7:00 PM, a0393909 <santosh.shilimkar at ti.com> wrote:
>> On 06/18/2012 02:10 PM, Daniel Lezcano wrote:
>>> Dear all,
>>> A few weeks ago, Peter De Schrijver proposed a patch  to allow per
>>> cpu latencies. We had a discussion about this patchset because it
>>> reverse the modifications Deepthi did some months ago  and we may
>>> want to provide a different implementation.
>>> The Linaro Connect  event bring us the opportunity to meet people
>>> involved in the power management and the cpuidle area for different SoC.
>>> With the Tegra3 and big.LITTLE architecture, making per cpu latencies
>>> for cpuidle is vital.
>>> Also, the SoC vendors would like to have the ability to tune their cpu
>>> latencies through the device tree.
>>> We agreed in the following steps:
>>> 1. factor out / cleanup the cpuidle code as much as possible
>>> 2. better sharing of code amongst SoC idle drivers by moving common bits
>>> to core code
>>> 3. make the cpuidle_state structure contain only data
>>> 4. add a API to register latencies per cpu
>>> These four steps impacts all the architecture. I began the factor out
>>> code / cleanup  and that has been accepted upstream and I proposed
>>> some modifications  but I had a very few answers.
>> Another thing which we discussed is bringing the CPU cluster/package
>> notion in the core idle code. Couple idle did bring that idea to some
>> extent but in can be further extended and abstracted. Atm, most of
>> the work is done in back-end cpuidle drivers which can be easily
>> abstracted if the "cluster idle" notion is supported in the core layer.
> Are you considering the "cluster idle" as one of the topic ?
Yes, absolutely. ATM, I am looking for refactoring the cpuidle code and
cleanup whenever is possible.
<http://www.linaro.org/> Linaro.org │ Open source software for ARM SoCs
Follow Linaro: <http://www.facebook.com/pages/Linaro> Facebook |
<http://twitter.com/#!/linaroorg> Twitter |
More information about the linaro-dev