Hi, On 18/05/18 12:04, Grant Likely wrote: > I'm adding some EBBR text around the CPU state at boot and I've lost > track of what is being done for multicore bringup. What is the current > state-of-the-art for multicore boot protocol when PSCI isn't available?
It is my understanding that for arm64 PSCI is the only accepted SMP bringup method. Now the first ARM64 hardware platform didn't have EL3, but wanted to have KVM running, so there was this decision to allow this *one* alternative method to enable this platform. If I understand Will and Catalin correctly, there is a strong push for *no* other methods being added to the kernel. So for ARM64 the answer should be: PSCI or spin table. Full stop. For ARM it's quite a different story, though. "New" platforms tend to implement PSCI, but there are quite some platforms out there with their own methods. Not sure we care about them? Actually, what is the purpose of the EBBR elaborating on SMP bringup in the first place? Cheers, Andre. > SBBR allows for the MP Boot Protocol; with the intend of phasing it out: > > https://acpica.org/sites/acpica/files/MP%20Startup%20for%20ARM%20platforms.doc > > > The kernel documents the spin table method: > > https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git/tree/Documentation/arm64/booting.txt > > > What are the cool kids currently doing here? > > g. > _______________________________________________ > Arm.ebbr-discuss mailing list > [email protected] _______________________________________________ boot-architecture mailing list [email protected] https://lists.linaro.org/mailman/listinfo/boot-architecture
