Re: [Qemu-devel] [PATCH RESEND v1 4/8] target-microblaze: Convert version_mask to a CPU property

[Alistair Francis]

On Fri, Jun 5, 2015 at 10:42 AM, Edgar E. Iglesias
<address@hidden> wrote:
> On Thu, Jun 04, 2015 at 11:23:19AM +1000, Alistair Francis wrote:
>> Originally the version_mask PVR bits were manually set for each
>> machine. This is a hassle and difficult to read, instead set them
>> based on the CPU properties.
>>
>> Signed-off-by: Alistair Francis <address@hidden>
>> ---
>>  hw/microblaze/petalogix_ml605_mmu.c |    3 ++-
>>  target-microblaze/cpu-qom.h         |    1 +
>>  target-microblaze/cpu.c             |    4 +++-
>>  3 files changed, 6 insertions(+), 2 deletions(-)
>>
>> diff --git a/hw/microblaze/petalogix_ml605_mmu.c 
>> b/hw/microblaze/petalogix_ml605_mmu.c
>> index 5f341c4..f52654c 100644
>> --- a/hw/microblaze/petalogix_ml605_mmu.c
>> +++ b/hw/microblaze/petalogix_ml605_mmu.c
>> @@ -70,7 +70,7 @@ static void machine_cpu_reset(MicroBlazeCPU *cpu)
>>
>>      env->pvr.regs[10] = 0x0e000000; /* virtex 6 */
>>      /* setup pvr to match kernel setting */
>> -    env->pvr.regs[0] = (env->pvr.regs[0] & ~PVR0_VERSION_MASK) | (0x14 << 
>> 8);
>> +    env->pvr.regs[0] |= (0x14 << 8);
>>      env->pvr.regs[4] = 0xc56b8000;
>>      env->pvr.regs[5] = 0xc56be000;
>>  }
>> @@ -99,6 +99,7 @@ petalogix_ml605_init(MachineState *machine)
>>      object_property_set_bool(OBJECT(cpu), true, "dcache-writeback",
>>                               &error_abort);
>>      object_property_set_bool(OBJECT(cpu), true, "endi", &error_abort);
>> +    object_property_set_bool(OBJECT(cpu), true, "version_mask", 
>> &error_abort);
>>      object_property_set_bool(OBJECT(cpu), true, "realized", &error_abort);
>>
>>      /* Attach emulated BRAM through the LMB.  */
>> diff --git a/target-microblaze/cpu-qom.h b/target-microblaze/cpu-qom.h
>> index 85b8f75..b6c6374 100644
>> --- a/target-microblaze/cpu-qom.h
>> +++ b/target-microblaze/cpu-qom.h
>> @@ -67,6 +67,7 @@ typedef struct MicroBlazeCPU {
>>          bool usemmu;
>>          bool dcache_writeback;
>>          bool endi;
>> +        bool version_mask;
>>      } cfg;
>>
>>      CPUMBState env;
>> diff --git a/target-microblaze/cpu.c b/target-microblaze/cpu.c
>> index f40df43..849c737 100644
>> --- a/target-microblaze/cpu.c
>> +++ b/target-microblaze/cpu.c
>> @@ -115,7 +115,8 @@ static void mb_cpu_realizefn(DeviceState *dev, Error 
>> **errp)
>>      env->pvr.regs[0] |= (cpu->cfg.stackprot ? PVR0_SPROT_MASK : 0) |
>>                          (cpu->cfg.usefpu ? PVR0_USE_FPU_MASK : 0) |
>>                          (cpu->cfg.usemmu ? PVR0_USE_MMU_MASK : 0) |
>> -                        (cpu->cfg.endi ? PVR0_ENDI_MASK : 0);
>> +                        (cpu->cfg.endi ? PVR0_ENDI_MASK : 0) |
>> +                        (cpu->cfg.endi ? ~PVR0_VERSION_MASK : 0);
>
> This looks wrong...
>
> My guess is that this should be:
> cpu->cfg.version_mask ? PVR0_VERSION_MASK : 0

So looking at the spec more the version mask should be a two byte
number that indicated the version. I can't see it in the DTS,  so I
think it should be a settable number, not a bool.

I'm not sure why it zeroes it out though,

Thanks,

Alistair

>
> and that maybe the ml605_mmu board is trying to disable the version mask,
> e.g setting it to false.
>
> Can you double check that it matches with dts and specs?
>
>
>>
>>      env->pvr.regs[2] |= (cpu->cfg.usefpu ? PVR2_USE_FPU_MASK : 0) |
>>                          (cpu->cfg.usefpu > 1 ? PVR2_USE_FPU2_MASK : 0);
>> @@ -176,6 +177,7 @@ static Property mb_properties[] = {
>>      DEFINE_PROP_BOOL("dcache-writeback", MicroBlazeCPU, 
>> cfg.dcache_writeback,
>>                       false),
>>      DEFINE_PROP_BOOL("endi", MicroBlazeCPU, cfg.endi, false),
>> +    DEFINE_PROP_BOOL("version-mask", MicroBlazeCPU, cfg.version_mask, 
>> false),
>>      DEFINE_PROP_END_OF_LIST(),
>>  };
>>
>> --
>> 1.7.1
>>
>