Re: [Qemu-devel] [Qemu-arm] [PATCH 1/2] target/arm: Set S and PTW in 64-bit PAR format

["Alex Bennée" <alex.bennee@linaro.org>]

Peter Maydell <peter.maydell@linaro.org> writes:

> On 5 November 2018 at 16:24, Alex Bennée <alex.bennee@linaro.org> wrote:
>>
>> Peter Maydell <peter.maydell@linaro.org> writes:
>>
>>> In do_ats_write() we construct a PAR value based on the result
>>> of the translation.  A comment says "S2WLK and FSTAGE are always
>>> zero, because we don't implement virtualization".
>>> Since we do in fact now implement virtualization, add the missing
>>> code that sets these bits based on the reported ARMMMUFaultInfo.
>>>
>>> (These bits are named PTW and S in ARMv8, so we follow that
>>> convention in the new comments in this patch.)
>>>
>>> Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
>>> ---
>>>  target/arm/helper.c | 10 ++++++----
>>>  1 file changed, 6 insertions(+), 4 deletions(-)
>>>
>>> diff --git a/target/arm/helper.c b/target/arm/helper.c
>>> index 43afdd082e1..dc849b09893 100644
>>> --- a/target/arm/helper.c
>>> +++ b/target/arm/helper.c
>>> @@ -2344,10 +2344,12 @@ static uint64_t do_ats_write(CPUARMState *env, uint64_t value,
>>>
>>>              par64 |= 1; /* F */
>>
>> To aid readability, mainly for those not familiar like me, maybe:
>>
>>   par64 |= 1; /* PAR_EL1.F == 1, failed translation */
>
> That's in the existing code...

I know, it was just a suggestion to help make it clearer there are two
forms when you are reading the register definition.

--
Alex Bennée