On 06/25/2012 02:58 PM, Shilimkar, Santosh wrote: > On Mon, Jun 18, 2012 at 7:00 PM, a0393909 <santosh.shilimkar@xxxxxx> wrote: >> Daniel, >> >> >> On 06/18/2012 02:10 PM, Daniel Lezcano wrote: >>> >>> >>> Dear all, >>> >>> A few weeks ago, Peter De Schrijver proposed a patch [1] to allow per >>> cpu latencies. We had a discussion about this patchset because it >>> reverse the modifications Deepthi did some months ago [2] and we may >>> want to provide a different implementation. >>> >>> The Linaro Connect [3] 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 [4] and that has been accepted upstream and I proposed >>> some modifications [5] 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 | <http://www.linaro.org/linaro-blog/> Blog
