Re: [Qemu-devel] [PATCH qom-next 11/12] target-i386: initialize APIC at CPU level

[Jan Kiszka]

On 2012-05-30 16:27, Igor Mammedov wrote:
>>> +
>>> +#ifndef CONFIG_USER_ONLY
>>> +#define MSI_ADDR_BASE 0xfee00000
>>> +
>>> +static void x86_cpu_apic_init(X86CPU *cpu, Error **errp)
>>> +{
>>> +    static int apic_mapped;
>>> +    CPUX86State *env =&cpu->env;
>>> +
>>> +    if (env->apic_state == NULL) {
>>> +        return;
>>> +    }
>>> +
>>> +    if (qdev_init(env->apic_state)) {
>>> +        error_set(errp, QERR_DEVICE_INIT_FAILED,
>>> +                  object_get_typename(OBJECT(env->apic_state)));
>>> +        return;
>>> +    }
>>> +
>>> +    /* XXX: mapping more APICs at the same memory location */
>>> +    if (apic_mapped == 0) {
>>> +        /* NOTE: the APIC is directly connected to the CPU - it is not
>>> +           on the global memory bus. */
>>> +        /* XXX: what if the base changes? */
>>> +        sysbus_mmio_map(sysbus_from_qdev(env->apic_state), 0, 
>>> MSI_ADDR_BASE);
>>> +        apic_mapped = 1;
>>>       }
>>>   }
>>> +#endif
>>>
>>>   void x86_cpu_realize(Object *obj, Error **errp)
>>>   {
>>>       X86CPU *cpu = X86_CPU(obj);
>>>
>>> +    x86_cpu_apic_init(cpu, errp);
>>> +    if (error_is_set(errp)) {
>>> +        return;
>>> +    }
>>> +
>>
>> I guess you are lacking #ifndef CONFIG_USER_ONLY here already (for the
>> sake of bisectability). Or, likely better, let x86_cpu_apic_init do
>> nothing for usermode emulation.
> initially x86_cpu_apic_init() was doing nothing for usermode, hence lack of
> #ifndef CONFIG_USER_ONLY, but then for patch 12/12 #ifndef CONFIG_USER_ONLY
> required here any way so I've removed usermode stub x86_cpu_apic_init() and
> squashed change in wrong patch :(.
> 
> And since I need #ifndef in initfn anyway then probably there is no point
> in having x86_cpu_apic_init(), I'll move its body in initfn then.

I think a function is cleaner, and we have some other examples for this
already in this context. Its body could easily be #ifdef'ed out (the
other reason for #ifdef in the initfn are temporary, no?).

Jan

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