Alpine offers armv7 support, if you check supported SoC,
https://wiki.alpinelinux.org/wiki/Alpine_on_ARM
exynos5250-smdk5250 is listed there as supported, and Nexus 10 has the same SoC, and they don't have much documentations. Anyhow is it possible to make it boot on Nexus 10?https://wiki.alpinelinux.org/wiki/Alpine_on_ARM