On Fri, 29 Mar 2013, Nicolas Pitre wrote: > On Fri, 29 Mar 2013, Stefano Stabellini wrote: > > > On Fri, 29 Mar 2013, Nicolas Pitre wrote: > > > On Fri, 29 Mar 2013, Stefano Stabellini wrote: > > > > > > > If PSCI initializes correctly and PSCI SMP operations are available, > > > > use them. > > > > This is required for SMP support in Dom0 on Xen. > > > > > > > > Signed-off-by: Stefano Stabellini <stefano.stabell...@eu.citrix.com> > > > > CC: will.dea...@arm.com > > > > CC: a...@arndb.de > > > > CC: marc.zyng...@arm.com > > > > CC: li...@arm.linux.org.uk > > > > CC: n...@linaro.org > > > > > > I'd suggest you also include in your series the patch I posted earlier > > > providing a runtime mdesc->smp_init method as well. > > > > OK. > > > > > > > This way the > > > priority order would be: > > > > > > - If mdesc->smp_init is non null then use that. > > > > > > - Otherwise, if PSCI is available then use that. > > > > > > - Otherwise use mdesc->smp. > > > > > > This way, if the PSCI default has to be overriden (like in the MCPM case > > > because it needs to wrap PSCI itself, or to cover Rob's concern) then > > > this can be achieved at run time on a per mdesc basis. > > > > Actually that's not a bad idea, it could make everybody happy. > > What about the following, in this precise order: > > > > - if a xen hypervisor node is present on device tree, use PSCI; > > - otherwise if mdesc->smp_init is non null then use it; > > - otherwise if PSCI is available then use it; > > - otherwise use mdesc->smp. > > > > It's the most practical solution to satisfy everybody's needs. > > Maybe I'm missing something obvious, but why can't xen declare a mdesc > of its own? Given it is going to tweak the DT passed to the kernel > anyway that shouldn't be a problem. > > That would be more eleguant than adding xen exception hooks in generic > code.
I guess I could introduce a Xen-enabled mdesc for all the platforms we intend to support, but as the list of boards with virtualization extensions grow, also the list of Xen-enabled mdescs would grow accordingly. We would end up with dozen (more?) of Xen mdescs. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
