Re: [Qemu-devel] [RFC PATCH 04/21] target-arm: preserve RAO/WI bits of ARMv7 SCTLR

[Fedorov Sergey <s.fedorov@samsung.com>]

On 12/03/2013 04:17 PM, Peter Crosthwaite wrote:
> On Tue, Dec 3, 2013 at 6:48 PM, Sergey Fedorov <s.fedorov@samsung.com> wrote:
>> From: Svetlana Fedoseeva <s.fedoseeva@samsung.com>
>>
>> Signed-off-by: Svetlana Fedoseeva <s.fedoseeva@samsung.com>
>> Signed-off-by: Sergey Fedorov <s.fedorov@samsung.com>
>> ---
>>   target-arm/helper.c |    4 ++++
>>   1 file changed, 4 insertions(+)
>>
>> diff --git a/target-arm/helper.c b/target-arm/helper.c
>> index 6642e53..d7922ad 100644
>> --- a/target-arm/helper.c
>> +++ b/target-arm/helper.c
>> @@ -1507,6 +1507,10 @@ static const ARMCPRegInfo lpae_cp_reginfo[] = {
>>
>>   static int sctlr_write(CPUARMState *env, const ARMCPRegInfo *ri, uint64_t value)
>>   {
>> +    if (arm_feature(env, ARM_FEATURE_V7)) {
>> +        value = value | 0x00c50078; /* This bits are RAO/WI */
> Magic number. "these bits ".

Would be acceptable to substitute this magic number with "bitshifted 
constants combined with bitwise or", e.g. as in vmsa_ttbcr_raw_write()?

>
>> +    }
>> +
>>       env->cp15.c1_sys = value;
>>       /* ??? Lots of these bits are not implemented.  */
>>       /* This may enable/disable the MMU, so do a TLB flush.  */
>> --
>> 1.7.9.5
>>
>>
>

-- 
Best regards,
Sergey Fedorov, Junior Software Engineer,
Samsung R&D Institute Rus.
E-mail: s.fedorov@samsung.com