Re: [PATCH] linux-user: Emulate /proc/cpuinfo on aarch64 and arm

[Helge Deller]

On 8/1/23 16:22, Peter Maydell wrote:
> On Tue, 1 Aug 2023 at 14:57, Helge Deller <deller@gmx.de> wrote:
> > Add emulation for /proc/cpuinfo for arm architecture.
> > The output below mimics output as seen on debian porterboxes.
>
>
> > +#if defined(TARGET_AARCH64) || defined(TARGET_ARM)
> > +static int open_cpuinfo(CPUArchState *cpu_env, int fd)
> > +{
> > +    int i, num_cpus;
> > +    const int is64 = TARGET_ABI_BITS == 64;
> > +
> > +    num_cpus = sysconf(_SC_NPROCESSORS_ONLN);
> > +    for (i = 0; i < num_cpus; i++) {
> > +        dprintf(fd, "processor\t: %d\n", i);
> > +        if (!is64) {
> > +            dprintf(fd, "model name\t: ARMv7 Processor rev 2 (v7l)\n");
> > +        }
> > +        dprintf(fd, "BogoMIPS\t: %d.00\n", is64 ? 100 : 50);
> > +        dprintf(fd, "Features\t: %s\n",
> > +                is64 ? "fp asimd evtstrm cpuid"
> > +                     : "half thumb fastmult vfp edsp thumbee vfpv3 " \
> > +                       "tls idiva idivt vfpd32 lpae");
> > +        dprintf(fd, "CPU implementer\t: 0x%d\n", is64 ? 50 : 56);
> > +        dprintf(fd, "CPU architecture: %d\n",    is64 ? 8 : 7);
> > +        dprintf(fd, "CPU variant\t: 0x%d\n",     is64 ? 0 : 2);
> > +        dprintf(fd, "CPU part\t: 0x%d\n",        is64 ? 0 : 584);
> > +        dprintf(fd, "CPU revision\t: %d\n\n",    is64 ? 1 : 2);
>
> If you want to do this you should hook it up to what the
> CPU being emulated actually is and what features it has.
> (Compare how we set the hwcaps.)

Nice!
I didn't know about those elf hwcaps...
I'll respin.

Thanks,
Helge