Re: [PATCH v2 2/3] sam460ex: Remove FDT_PPC dependency from KConfig

[Paolo Bonzini <pbonzini@redhat.com>]

On 04/01/21 02:51, BALATON Zoltan wrote:
> On Thu, 31 Dec 2020, BALATON Zoltan via wrote:
>> Dependency on FDT_PPC was added in commit b0048f76095
>> ("hw/ppc/Kconfig: Only select FDT helper for machines using it") but
>> it does not seem to be really necessary so remove it again.
>>
>> Signed-off-by: BALATON Zoltan <balaton@eik.bme.hu>
>> ---
>> v2: Do not remove PPC405, reworded commit message
>>
>> hw/ppc/Kconfig | 1 -
>> 1 file changed, 1 deletion(-)
>>
>> diff --git a/hw/ppc/Kconfig b/hw/ppc/Kconfig
>> index 8548f42b0d..f1e1be208e 100644
>> --- a/hw/ppc/Kconfig
>> +++ b/hw/ppc/Kconfig
>> @@ -64,7 +64,6 @@ config SAM460EX
>>     select SMBUS_EEPROM
>>     select USB_EHCI_SYSBUS
>>     select USB_OHCI
>> -    select FDT_PPC
>>
>> config PREP
>>     bool
> 
> Something is still not right with this, I've noticed that a few other 
> boards also have this option selected but they don't need fdt.o that's 
> gated by this option in meson.build. That fdt.o is only needed by 
> PSERIES and POWERNV but removing FDT_PPC from other boards I get:
> 
> ../hw/ppc/sam460ex.c:43:10: fatal error: libfdt.h: No such file or 
> directory
>   #include <libfdt.h>
> 
> so apparently this switch also pulls in the necessary CPPFLAGS or libfdt 
> dependency. Is there a separate switch for that or we can only get it 
> with fdt.o. Not a big deal just not trivial why we need an option that 
> at first sight select a source file which we don't need. I think I'll 
> drop this patch for now when resending the series.

You can always do

ppc_ss.add(when: 'CONFIG_SAM460EX', if_true: [files('sam460ex.c'), fdt])

if you want to get rid of the flag.

Paolo