On 9 December 2017 at 01:08, Eduardo Habkost <ehabk...@redhat.com> wrote: > On Thu, Dec 07, 2017 at 07:37:31PM +0000, Peter Maydell wrote: >> On 7 December 2017 at 18:14, Peter Maydell <peter.mayd...@linaro.org> wrote: >> > This patchset adds support for '-cpu max' to Arm, along the lines >> > of the existing support we have for x86 targets: >> > >> > * under KVM, -cpu max is the same as -cpu host >> > * under TCG, -cpu max means "emulate with as many features as >> > possible" >> >> Forgot to mention: -cpu max for qemu-system-aarch64 will >> be a 64-bit cpu, and for qemu-system-arm it will be a 32-bit >> cpu. (This differs from all the other TCG CPU types, which >> behave the same for the 32-bit and 64-bit binaries. I think >> it is the same way that x86 -cpu max works, though.) > > Are they going to be represented by two different QOM type names? > > (In the case of x86, all the CPU classes have different names on > qemu-system-x86_64 and qemu-system-i386).
(Just pulling this thread up from before Christmas...) I guess a better way to approach this would be to ask: how is x86 implementing -cpu max, ie what is the required view of things that I need to provide for target/arm in order to have QEMU behave the same way x86 does? Did we write any user-facing documentation for this feature? (The code in this patchset makes '-cpu max' give the same QOM type name for both qemu-system-arm and qemu-system-aarch64, with different behaviour depending on the binary. If that means we don't provide the same behaviour as x86 then I can change that, but I'm not sure where the difference is exposed to the user?) thanks -- PMM
