On 9 July 2012 12:55, Shilimkar, Santosh <santosh.shilim...@ti.com> wrote: > Vincent, > On Mon, Jul 9, 2012 at 2:57 PM, Vincent Guittot > <vincent.guit...@linaro.org> wrote: >> Use cpu compatibility field and clock-frequency field of DT to >> estimate the capacity of each core of the system and to update >> the cpu_power field accordingly. >> This patch enables to put more running tasks on big cores than >> on LITTLE ones. But this patch doesn't ensure that long running >> tasks will run on big cores and short ones on LITTLE cores. >> >> Signed-off-by: Vincent Guittot <vincent.guit...@linaro.org> >> Reviewed-by: Namhyung Kim <namhy...@kernel.org> >> --- >> arch/arm/kernel/topology.c | 153 >> ++++++++++++++++++++++++++++++++++++++++++++ >> 1 file changed, 153 insertions(+) >> > Sorry for not giving this comment on previous version but we should also > have a way to provide the big.LITTLE information without Device Tree. > May be a platform device/data.
Hi Santosh, I had thought of adding such additional way to set cpu_power of big.LITTLE but my conclusion was -it's a new platform so it should come with DT -DT is already required by other patches linked to big.LITTLE (http://lists.infradead.org/pipermail/linux-arm-kernel/2012-January/080873.html) -There is no device that can be easily used to get such information at this early boot stage. > > I know we are moving DT way, but remember apart from core kernel > infrastructure, to have a complete product build with DT means all the > drivers must be already supporting DT which is not the case with > many huge driver sub-systems like USB, display subsystem, Audio etc. > > Having that support would greatly help for the SOC's which have not yet > reached to stage where entire SOC is DT compliant and want to use > big.LITTLE infrastructure. Can't you support both type of devices on your platform ? You can move your device to DT mode when it is supported ? Regards, Vincent > > Regards > Santosh -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
