Re: [PATCH V2 15/46] arm64/sysreg: Add register fields for PFAR_EL1

[Anshuman Khandual <anshuman.khandual@arm.com>]

On 12/18/24 21:12, Eric Auger wrote:
> Hi Anshuman,
> 
> On 12/10/24 06:52, Anshuman Khandual wrote:
>> This adds register fields for PFAR_EL1 as per the definitions based on
>> DDI0601 2024-09.
>>
>> Cc: Catalin Marinas <catalin.marinas@arm.com>
>> Cc: Will Deacon <will@kernel.org>
>> Cc: Mark Brown <broonie@kernel.org>
>> Cc: linux-arm-kernel@lists.infradead.org
>> Cc: linux-kernel@vger.kernel.org
>> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
>> ---
>>  arch/arm64/tools/sysreg | 7 +++++++
>>  1 file changed, 7 insertions(+)
>>
>> diff --git a/arch/arm64/tools/sysreg b/arch/arm64/tools/sysreg
>> index 18b814ff2c41..e33edb41721a 100644
>> --- a/arch/arm64/tools/sysreg
>> +++ b/arch/arm64/tools/sysreg
>> @@ -3533,3 +3533,10 @@ Field	5	F
>>  Field	4	P
>>  Field	3:0	Align
>>  EndSysreg
>> +
>> +Sysreg	PFAR_EL1	3	0	6	0	5
>> +Field	63	NS
>> +Field	62	NSE
>> +Res0	61:56
>> +Field	55:0	PA
> Just wondering: part of the PA definition depends on FEAT_D128 or
> FEAT_LPA and the reset field value is UNKNOWN if the feature is not
> available. Shouldn't introduce separate fields directly?
Generated PFAR_EL1_PA_MASK aka GENMASK_ULL(55, 0) should cover all the
cases for PA i.e 48 bits, LPA, D128 etc. Although individual use cases
will have to trim the mask subsequently as required.

Are you suggesting something like the following instead where the user
will have to concatenate these fields selectively to find the required
PA mask ?

Field	55:52	PA_D128
Field	51:48	PA_LPA
Field	47:0	PA