Nicolas Pitre <nicolas.pitre@xxxxxxxxxx> writes: > On Sat, 7 Jun 2014, Abhilash Kesavan wrote: > >> Hi Nicolas, >> >> The first man of the incoming cluster enables its snoops via the >> power_up_setup function. During secondary boot-up, this does not occur >> for the boot cluster. Hence, I enable the snoops for the boot cluster >> as a one-time setup from the u-boot prompt. After secondary boot-up >> there is no modification that I do. > > OK that's good. > >> Where should this be ideally done ? > > If I remember correctly, the CCI can be safely activated only when the > cache is disabled. So that means the CCI should ideally be turned on > for the boot cluster (and *only* for the boot CPU) by the bootloader. > > Now... If you _really_ prefer to do it from the kernel to avoid > difficulties with bootloader updates, then it should be possible to do > it from the kernel by temporarily turning the cache off. This is not a > small thing but the MCPM infrastructure can be leveraged. Here's what I > tried on a TC2 which might just work for you as well: FWIW, I dropped the u-boot hack I was using to enable CCI and tested this patch (with a cut/paste of the TC2 specific stuff into mach-exynos/mcpm-exynos.c) along with Doug's patch[1] and and confirm that all 8 cores boot up on the Chromebook2 using linux-next. Kevin [1] http://lists.infradead.org/pipermail/linux-arm-kernel/2014-June/262440.html -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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