Re: [PATCH rc3 02/30] target/avr: Introduce AVR CPU class object

[Aleksandar Markovic]

09:03 Pon, 27.01.2020. Philippe Mathieu-Daudé <address@hidden> је написао/ла:
>
> On 1/27/20 3:39 AM, Aleksandar Markovic wrote:
> >> +static void avr_cpu_initfn(Object *obj)
> >> +{
> >> +    AVRCPU *cpu = AVR_CPU(obj);
> >> +
> >> +    cpu_set_cpustate_pointers(cpu);
> >> +
> >> +#ifndef CONFIG_USER_ONLY
> >> +    /* Set the number of interrupts supported by the CPU. */
> >> +    qdev_init_gpio_in(DEVICE(cpu), avr_cpu_set_int,
> >> +            sizeof(cpu->env.intsrc) * 8);
> >> +#endif
> >> +}
> >
> > A question for Michael:
> >
> > What is CONFIG_USER_ONLY doing here, if we know AVR cores from this
> > series doesn't have and will never have user mode, since they do not
> > work with the kernel?
> >
> > Do you plan to support some AVR 32-bit CPUs in the same file, which
> > would be able to have linux-user mode? But, in this case, many files
> > must be completely redone. My advice is to separate them completely,
> > and that this file supports only 8-bit AVR cores, and in that case
> > checks for CONFIG_USER_ONLY do not make sense.
>
> You are right, CONFIG_USER_ONLY doesn't make sense.
>
> Suggestion: add in target/avr/cpu.h:
>
>    #ifdef CONFIG_USER_ONLY
>    #error "AVR 8-bit does not support user mode"
>    #endif
>

I agree with your suggestion, in fact, it is an excellent one.