Re: [Qemu-arm] [RFC PATCH 0/2] target: Build with CONFIG_SEMIHOSTING disabled

[Philippe Mathieu-Daudé]

On 5/31/19 6:21 PM, Peter Maydell wrote:
> On Fri, 31 May 2019 at 16:47, Philippe Mathieu-Daudé <address@hidden> wrote:
>>
>> Amusingly Miroslav and myself hit this issue at the same time.
>>
>> Currently there is no way to pass a CONFIG_X to sources in target/,
>> except via a Makefile rule (and filling with stubs).
>>
>> Paolo says this is on purpose, CONFIG_X selectors are meant for
>> devices and we try to avoid having config-devices.mak in
>> config-target.h.
> 
> ...but some things in target/ are devices (like the Arm CPUs,
> which inherit from TYPE_DEVICE).
> 
> Is there a way we can have a Kconfig fragment that expresses
> "if you asked for an Arm CPU then this should 'select SEMIHOSTING'" ?

Yes, but inversely, we can also deselect a feature, and all features
that requires it get deselected. My guess is Miroslav is building a
KVM-only QEMU, but upstream does not allow to build ARM without TCG.

I'll see what happened to Samuel series "Support disabling TCG on ARM"
and see if it can be salvaged:
https://lists.gnu.org/archive/html/qemu-devel/2018-11/msg02451.html

I suppose in this thread:
https://lists.gnu.org/archive/html/qemu-devel/2018-11/msg05641.html
you refer to this series (not yet merged):
https://lists.gnu.org/archive/html/qemu-devel/2019-05/msg03137.html

I'll try to figure what "KVM injection of interrupts" is.