Re: [Qemu-devel] [PATCH] make: automatically include dependencies in recursive subdir rules (v2)

[Jan Kiszka]

On 2012-06-18 14:47, Anthony Liguori wrote:
> On 06/18/2012 04:13 AM, Jan Kiszka wrote:
>> On 2012-06-18 02:32, Andreas Färber wrote:
>>> Am 18.06.2012 02:01, schrieb Anthony Liguori:
>>> This will work technically but I still feel this is wrong semantically.
>>> The pre-Paolo and current way is picking specific files from the hw/kvm/
>>> directory. Your change above implies that in hw/kvm/ only x86 files can
>>> live, which I dislike. As suggested before, I would prefer if x86-only
>>> files were moved to an x86-specific location - the place for that
>>> existing since Paolo's refactoring would be hw/i386/. CC'ing Jan. That
>>> would match Paolo's reply in the unicore32 thread on future file
>>> placement. Alternatives would be hw/i386/kvm/ or hw/kvm/i386/; we're
>>> talking about a handful of files only though, so I don't think they
>>> require a new subdirectory.
>>
>> Some per-arch separation is required, at least in the build process.
>> We'll see power and arm stubs for in-kernel devices soon.
> 
> i8259.o i8254.o ioapic.o don't need to be arch specific

In theory. In practice they carry quite a bit of the PC architecture
(i8254: HPET and PC speaker port, i8259: ELCR). Maybe not the IOAPIC. It
was once reused on IA64, but that arch is dead.

> 
> apic.o ought to be renamed to lapic.o and moved to target-i386/kvm/

"apic" is fine as name as the code covers both cases.

Should be move hw/apic* as well?

> 
> I think clock.o also more than likely belongs in target-i386/kvm/.  It would 
> have to be implemented as part of the CPU core if it ever existed IRL.
> 
> In general, if is logically part of a CPU core, it ought to be in 
> target-$(ARCH).  Otherwise, it shouldn't be built as a target specific object.

There are some practical things like lacking types or defines in the KVM
API that most probably prevent building certain KVM devices for all
targets unconditionally.

Jan

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