On Thu, 4 Mar 2021 at 16:39, Philippe Mathieu-Daudé <f4...@amsat.org> wrote: > > On 3/3/21 7:54 PM, Richard Henderson wrote: > > On 3/3/21 10:45 AM, Claudio Fontana wrote: > >> It is a bit weird that qemu-system-aarch64 runs with a cortex-a15 > >> model tbh, as cortex-a15 is not capable of aarch64. > > > > No, but qemu-system-aarch64 is capable of 32-bit emulation (because most > > 64-bit cpus retain 32-bit mode). It takes no extra effort to run > > cortex-a15 than it does a cortex-a57. > > IIRC qemu-system-arm starts the aa64 cores in 32-bit mode, while
...no, it simply doesn't have them at all; it only has the 32-bit-only cores. We only support '64-bit core that starts in 32-bit mode' for KVM; it would be nice to have the TCG support for that but nobody's ever written it. > qemu-system-aarch64 in 64-bit (this gave me trouble because the > kernels for the raspi 64-bit SoCs are in 32-bit mode -- because > the GPU starts them in this mode). > > > I have wondered if we should have just one qemu-system-arm that does it > > all and drop the separate qemu-system-aarch64 -- or vice versa. But > > we've had the separation around so long I'm sure someone would be confused. > > That would be great cleanup IMHO. I figure it's not really worth the bother until/unless we ever some day get to the holy grail of "one binary that supports multiple target architectures", at which point we could have one qemu-system for everything... -- PMM
