Re: [Qemu-ppc] [PATCH] pseries: Implements h_read hcall

[Erlon Cruz]

I left them only to make it easy to read and keep the same sintax used
in the other functions.

On Sat, Feb 16, 2013 at 9:46 PM, David Gibson <address@hidden> wrote:
> On Fri, Feb 15, 2013 at 08:59:35AM -0200, Erlon Cruz wrote:
>> From: Erlon Cruz <address@hidden>
>>
>> This h_call is useful for DLPAR in future amongst other things. Given an 
>> index
>> it fetches the corresponding PTE stored in the htab.
>>
>> Signed-off-by: Erlon Cruz <address@hidden>
>> ---
>>  hw/spapr_hcall.c |   34 ++++++++++++++++++++++++++++++++++
>>  1 file changed, 34 insertions(+)
>>
>> diff --git a/hw/spapr_hcall.c b/hw/spapr_hcall.c
>> index 2889742..1065277 100644
>> --- a/hw/spapr_hcall.c
>> +++ b/hw/spapr_hcall.c
>> @@ -323,6 +323,39 @@ static target_ulong h_protect(PowerPCCPU *cpu, 
>> sPAPREnvironment *spapr,
>>      return H_SUCCESS;
>>  }
>>
>> +static target_ulong h_read(PowerPCCPU *cpu, sPAPREnvironment *spapr,
>> +                            target_ulong opcode, target_ulong *args)
>> +{
>> +    CPUPPCState *env = &cpu->env;
>> +    target_ulong flags = args[0];
>> +    target_ulong pte_index = args[1];
>> +    target_ulong v[4], r[4];
>> +    uint8_t *hpte;
>> +    int i, ridx, n_entries = 1;
>> +
>> +    if ((pte_index * HASH_PTE_SIZE_64) & ~env->htab_mask) {
>> +        return H_PARAMETER;
>> +    }
>> +
>> +    if (flags & H_READ_4) {
>> +        /* Clear the two low order bits */
>> +        pte_index &= ~(3ULL);
>> +        n_entries = 4;
>> +    }
>> +
>> +    hpte = env->external_htab + (pte_index * HASH_PTE_SIZE_64);
>> +
>> +    for (i = 0, ridx = 0; i < n_entries; i++) {
>> +        v[i] = ldq_p(hpte);
>> +        r[i] = ldq_p(hpte + (HASH_PTE_SIZE_64/2));
>
> There's no need for the v and r arrays.  You can just need temporaries
> for one entry as you store them one-by-one into args.
>
> Otherwise looks good.
>
> --
> David Gibson                    | I'll have my music baroque, and my code
> david AT gibson.dropbear.id.au  | minimalist, thank you.  NOT _the_ _other_
>                                 | _way_ _around_!
> http://www.ozlabs.org/~dgibson