Dear Jason Cooper, On Mon, 10 Feb 2014 12:39:57 -0500, Jason Cooper wrote: > > Note that we intentionally do not use the same compatible string as > > Armada 370/XP, as the current system-controller driver is far from > > exploiting all the possibilities of the hardware, and we may in the > > future discover differences between Armada 370/XP and Armada 380/385. > > I'd much prefer to add a new compatible string iff it accompanies > incompatible changes. > > For now, I think it's best to use 'marvell,armada-370-xp-system-controller' > in the dtsi file and change it when you introduce the incompatible > features. This doesn't work really well: if an user keeps an old DTB around, which uses the old compatible string, then you're screwed because there's no way a new kernel version can make the distinction between Armada 370/XP and Armada 380/385. If we discover than Armada 380/385 need a special quirk to really work reliably for example, but that this quirk doesn't apply to Armada 370/XP, then you have a serious problem. Therefore, I would like to really insist to have separate compatible strings for different SOCs. As an example, we used to have the same compatible string for the timer between Armada 370 and Armada XP, and later discovered that it was not possible due to a bug affecting only one of the two SOCs. Our experience clearly shows that sharing compatible strings is a bad idea, and having separate compatible strings from the beginning doesn't cost anything, and offers higher flexibility for the future. Thanks, Thomas -- Thomas Petazzoni, CTO, Free Electrons Embedded Linux, Kernel and Android engineering http://free-electrons.com _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@xxxxxxxxxxxxxxxxxxx http://lists.infradead.org/mailman/listinfo/linux-arm-kernel