>> >> The Non-US version of the Samsung Glaxy Note4 is powered by the >> >> Exynos7, which is an Octa Core A57/A53 in big.LITTLE config. >> >> Note4 with Qualcomm cpu is not US only device. So if you want to buy it >> with Exynos7 you have to check exactly what you buy. >> >> > I have mixed feelings about big.LITTLE based on my experience with the >> > (older, 32 bit) 5410. >> >> IIRC 5410 had wrong implementation of big.LITTLE or atleast incompatible >> with what came in all other cpus. > > .. and is rumoured to be broken (caching bugs) although I've > not experienced anything on mine.
We currently don't support any form of little.BIG in Fedora. Until recently the only SoCs that supported it were exynos based and their support for multiprocessor kernels was terrible let alone some of their more exotic features. There are now other devices out there with the technology and dev boards with it on board but again most of that support isn't upstream, eg AllWinner A80 basic support isn't upstream yet. The other SoC with similar technology is Tegra and while their upstream support overall is generally very good there doesn't appear to be any drivers etc for scaling between their single companion core and the rest. While the technology is cute it is very much designed for the mobile phone/tablet market to save battery when in the pocket but to have enough power to play/record hi def video and hence in the short term I don't believe it really fits our use case and hence I've not spent much more time than the occasional cursory glance to see if it's any less broken. Besides, after a couple of months, I'm yet to get any positive confirmation that people are actually able to use our kernel with any Exynos based device. Peter _______________________________________________ arm mailing list arm@lists.fedoraproject.org https://admin.fedoraproject.org/mailman/listinfo/arm