[OE-core] [PATCH] arch-arm64.inc: Do not append aarch64 in MACHINEOVERRIDES

[Junling Zheng]

On 2020/3/3 22:20, Peter Kjellerstedt wrote:
>> -----Original Message-----
>> From: Junling Zheng <zhengjunling at huawei.com>
>> Sent: den 3 mars 2020 15:14
>> To: Peter Kjellerstedt <peter.kjellerstedt at axis.com>; Khem Raj
>> <raj.khem at gmail.com>; openembedded-core at lists.openembedded.org
>> Cc: wangnan0 at huawei.com
>> Subject: Re: [OE-core] [PATCH] arch-arm64.inc: Do not append aarch64 in
>> MACHINEOVERRIDES
>>
>> On 2020/3/3 19:59, Peter Kjellerstedt wrote:
>>>> -----Original Message-----
>>>> From: openembedded-core-bounces at lists.openembedded.org <openembedded-
>> core-
>>>> bounces at lists.openembedded.org> On Behalf Of Junling Zheng
>>>> Sent: den 3 mars 2020 04:11
>>>> To: Khem Raj <raj.khem at gmail.com>; openembedded-
>>>> core at lists.openembedded.org
>>>> Cc: wangnan0 at huawei.com
>>>> Subject: Re: [OE-core] [PATCH] arch-arm64.inc: Do not append aarch64 in
>>>> MACHINEOVERRIDES
>>>>
>>>> On 2020/3/3 2:29, Khem Raj wrote:
>>>>>
>>>>>
>>>>> On 3/2/20 9:11 AM, Junling Zheng wrote:
>>>>>> Currently, for arch-arm64, poky will append the MACHINEOVERRIDES with
>>>>>> "aarch64:", which has the higher priority than
>> TRANSLATED_TARGET_ARCH.
>>>>>> So, for aarch64 big endian, the variable '<foo>_aarch64' will
>> override
>>>>>> not only '<foo>', but also '<foo>_aarch64-be', thus we will get an
>>>>>> incorrect variable.
>>>>>>
>>>>>> Signed-off-by: Junling Zheng <zhengjunling at huawei.com>
>>>>>> ---
>>>>>>   meta/conf/machine/include/arm/arch-arm64.inc | 2 --
>>>>>>   1 file changed, 2 deletions(-)
>>>>>>
>>>>>> diff --git a/meta/conf/machine/include/arm/arch-arm64.inc
>>>> b/meta/conf/machine/include/arm/arch-arm64.inc
>>>>>> index 53f4566815..32294bd218 100644
>>>>>> --- a/meta/conf/machine/include/arm/arch-arm64.inc
>>>>>> +++ b/meta/conf/machine/include/arm/arch-arm64.inc
>>>>>> @@ -4,8 +4,6 @@ require conf/machine/include/arm/arch-armv7ve.inc
>>>>>>     TUNEVALID[aarch64] = "Enable instructions for aarch64"
>>>>>>   -MACHINEOVERRIDES =. "${@bb.utils.contains('TUNE_FEATURES',
>> 'aarch64', 'aarch64:', '' ,d)}"
>>>>>> -
>>>>>
>>>>> if its removed here, where is it being added for other machines,
>>>> question is, should we treat aarch64 as LE equivalent of aarch64_be
>>>>> or should be treated as common aarch64 and a new define like
>> aarch64_le
>>>> defined.
>>>>>
>>>>
>>>> Currently, for arm64, we have aarch64_be to represent big endian, but
>> no
>>>> overrides to represent little endian only.
>>>>
>>>> So, IMO, we should treat aarch64 as little enaian only, like arm and
>>>> armeb.
>>>>
>>>>>>   # Little Endian base configs
>>>>>>   AVAILTUNES += "aarch64 aarch64_be"
>>>>>>   ARMPKGARCH_tune-aarch64 ?= "aarch64"
>>>
>>> Please, before removing "aarch64" from MACHINEOVERRIDES, add "armv8a" or
>>> similar. This is how it is done for the armv7* based chips. E.g., I
>> would
>>> expect to see tune-cortexa53.inc have:
>>>
>>> MACHINEOVERRIDES =. "${@bb.utils.contains('TUNE_FEATURES', 'cortexa53', 'armv8a:', '' ,d)}"
>>>
>>
>> arch-armv8a.inc has set "armv8a:" as overrides, and tune-cortexa53.inc
>> requires arch-armv8a.inc.
> 
> But it never adds "armv8a" (or ${TUNE_FEATURES_tune-armv8a}) to 
> TUNE_FEATURES, it adds "aarch64", so the above is never triggered...
> 

I guess the logic is: if you set DEFAULTTUNE as armv8a, then it will add "armv8a"
to TUNE_FEATURES, and then "armv8a:" will be added into MACHINEOVERRIDES. Am I right?

>>> Which corresponds to how it is done for armv7*.
>>>
>>> At least we currently rely on being able to do, e.g.:
>>>
>>> COMPATIBLE_MACHINE = "aarch64|armv7a|armv7ve"
>>>
>>> and if you remove "aarch64" from MACHINEOVERRIDES, we need a suitable
>>> substitute.
>>>
>>> //Peter
> 
> //Peter
> 
> 
> .
>