qemu-devel
[Top][All Lists]
Advanced

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Qemu-devel] [Qemu-ppc] [PATCH] booke_206_tlbwe: Discard invalid bit


From: Alexander Graf
Subject: Re: [Qemu-devel] [Qemu-ppc] [PATCH] booke_206_tlbwe: Discard invalid bits in MAS2
Date: Sun, 20 May 2012 12:18:53 +0200


On 20.05.2012, at 12:15, Alexander Graf <address@hidden> wrote:

> 
> 
> On 09.05.2012, at 15:28, Fabien Chouteau <address@hidden> wrote:
> 
>> The size of EPN field in MAS2 depends on page size. This patch adds a
>> mask to discard invalid bits in EPN field.
>> 
>> Definition of EPN field from e500v2 RM:
>> EPN Effective page number: Depending on page size, only the bits
>> associated with a page boundary are valid. Bits that represent offsets
>> within a page are ignored and should be cleared.
>> 
>> There is a similar (but more complicated) definition in PowerISA V2.06.
>> 
>> Signed-off-by: Fabien Chouteau <address@hidden>
>> ---
>> target-ppc/op_helper.c |   10 ++++++++--
>> 1 file changed, 8 insertions(+), 2 deletions(-)
>> 
>> diff --git a/target-ppc/op_helper.c b/target-ppc/op_helper.c
>> index 4ef2332..6bc64ad 100644
>> --- a/target-ppc/op_helper.c
>> +++ b/target-ppc/op_helper.c
>> @@ -4227,6 +4227,8 @@ void helper_booke206_tlbwe(void)
>>    uint32_t tlbncfg, tlbn;
>>    ppcmas_tlb_t *tlb;
>>    uint32_t size_tlb, size_ps;
>> +    target_ulong mask;
>> +
>> 
>>    switch (env->spr[SPR_BOOKE_MAS0] & MAS0_WQ_MASK) {
>>    case MAS0_WQ_ALWAYS:
>> @@ -4289,8 +4291,12 @@ void helper_booke206_tlbwe(void)
>>        tlb->mas1 |= (tlbncfg & TLBnCFG_MINSIZE) >> 12;
>>    }
>> 
>> -    /* XXX needs to change when supporting 64-bit e500 */
>> -    tlb->mas2 = env->spr[SPR_BOOKE_MAS2] & 0xffffffff;
>> +    /* Make a mask from TLB size to discard invalid bits in EPN field */
>> +    mask = ~(booke206_tlb_to_page_size(env, tlb)
> 
> This breaks execution of -cpu with qemu-system-ppc64, no?

-cpu e500 I mean of course :).

Alex



reply via email to

[Prev in Thread] Current Thread [Next in Thread]