On Saturday 21 November 2015 22:11:36 Måns Rullgård wrote: > Arnd Bergmann <arnd@xxxxxxxx> writes: > > On Saturday 21 November 2015 20:45:38 Måns Rullgård wrote: > >> On 21 November 2015 20:39:58 GMT+00:00, Arnd Bergmann <arnd@xxxxxxxx> wrote: > >> > >> The ARM ARM says anything with virt has idiv, lpae doesn't matter. > > > > Ok, and anything with virt also has lpae by definition. The question is > > whether we care about using idiv on cores that do not have lpae, or that > > have neither lpae nor virt. > > The question is, are there any such cores? GCC doesn't know of any, but > then it's missing most non-ARM designs. Exactly. Stephen should be able to find out about the Qualcomm cores, and http://comments.gmane.org/gmane.linux.ports.arm.kernel/426289 has some information about the others: * Brahma-B15 supports all three. * Dove (PJ4) reports idiv only in thumb mode, which I'm tempted to ignore for the kernel, as it supports neither lpae nor idiva. * Armada 370/XP (PJ4B) reports support for idiva and idivt, but according to https://groups.google.com/a/dartlang.org/forum/#!topic/reviews/9wvsJvq0YYY that may be a lie. * According to the same source, Krait fails to report idiva and idivt, but supports both anyway. However, I found reports on the web where /proc/cpuinfo correctly contains the flags on the same SoC (APQ8064) that was mentioned there, so maybe they were just running an old kernel. Arnd -- To unsubscribe from this list: send the line "unsubscribe linux-arm-msm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
