On 09/19/2011 06:35 AM, Alexander Graf wrote: > > On 17.09.2011, at 19:40, Blue Swirl wrote: > >> On Sat, Sep 17, 2011 at 5:15 PM, Alexander Graf <ag...@suse.de> wrote: >>> >>> Am 17.09.2011 um 18:58 schrieb Blue Swirl <blauwir...@gmail.com>: >>> >>>> On Sparc32, there is no need for a PV device. The CPU is woken up from >>>> halted state with an IPI. Maybe you could use this approach? >>> >>> The way it's done here is defined by u-boot and now also nailed down in the >>> ePAPR architecture spec. While alternatives might be more appealing, this >>> is how guests work today :). >> >> OK. I hoped that there were no implementations yet. The header (btw >> missing) should point to the spec.
The goal with the spin table stuff, suboptimal as it is, was something that would work on any powerpc implementation. Other implementation-specific release mechanisms are allowed, and are indicated by a property in the cpu node, but only if the loader knows that the OS supports it. > IIUC the spec that includes these bits is not finalized yet. It is however in > use on all u-boot versions for e500 that I'm aware of and the method Linux > uses to bring up secondary CPUs. It's in ePAPR 1.0, which has been out for a while now. ePAPR 1.1 was just released which clarifies some things such as WIMG. > Stuart / Scott, do you have any pointers to documentation where the spinning > is explained? https://www.power.org/resources/downloads/Power_ePAPR_APPROVED_v1.1.pdf -Scott
