Re: [PATCH v2] arm: Add Kconfig entry to select CONFIG_DTB_FILE

[Michal Orzel <michal.orzel@xxxxxxx>]

On 09.03.2021 14:32, Julien Grall wrote:
> 
> 
> On 09/03/2021 11:07, Jan Beulich wrote:
>> On 09.03.2021 11:20, Julien Grall wrote:
>>> On 09/03/2021 07:34, Michal Orzel wrote:
>>>> On 08.03.2021 15:31, Julien Grall wrote:
>>>>> On 08/03/2021 13:59, Michal Orzel wrote:
>>>>>> --- a/xen/arch/arm/Makefile
>>>>>> +++ b/xen/arch/arm/Makefile
>>>>>> @@ -68,7 +68,7 @@ extra-y += $(TARGET_SUBARCH)/head.o
>>>>>>       #obj-bin-y += ....o
>>>>>>     -ifdef CONFIG_DTB_FILE
>>>>>> +ifneq ($(CONFIG_DTB_FILE),"")
>>>>>>     obj-y += dtb.o
>>>>>>     AFLAGS-y += -DCONFIG_DTB_FILE=\"$(CONFIG_DTB_FILE)\"
>>>>>>     endif
>>>>>> @@ -137,8 +137,6 @@ asm-offsets.s: $(TARGET_SUBARCH)/asm-offsets.c
>>>>>>     xen.lds: xen.lds.S
>>>>>>         $(CPP) -P $(a_flags) -MQ $@ -o $@ $<
>>>>>>     -dtb.o: $(CONFIG_DTB_FILE)
>>>>>> -
>>>>>
>>>>> Why is this dropped?
>>>> 1)This line is not needed as it has no impact on creating dtb.o
>>>> 2)It causes the build failure once CONFIG_DTB_FILE option is in the 
>>>> Kconfig as string within quotes.
>>>
>>> Because of 1), this should have ideally be part of a separate patch. But
>>> I am OK to keep it in this patch so long it is explained in the commit
>>> message.
>>
>> Wasn't the intention to have dtb.o re-compiled when the blob
>> has changed? This would be lost with the removal of this line.
> 
> Ah yes. I was only thinking about a name change (this would be caught via the 
> update of the config header) and not a file update.
> 
I already pushed v3 but I agree. Something like this would do the job:
dtb.o: $(subst $\",,$(CONFIG_DTB_FILE))
to remove quotes