Re: [Qemu-devel] [PATCH] hw: Add VMware's GETHZ command.

[Don Slutz <Don@CloudSwitch.Com>]

On 08/31/12 12:22, Jan Kiszka wrote:
> On 2012-08-31 17:30, Don Slutz wrote:
>> This is known is linux as VMWARE_PORT_CMD_GETHZ.
>>
>> Signed-off-by: Don Slutz <Don@CloudSwitch.com>
>> ---
>>   hw/vmport.c |   22 +++++++++++++++++++++-
>>   1 files changed, 21 insertions(+), 1 deletions(-)
>>
>> diff --git a/hw/vmport.c b/hw/vmport.c
>> index a4f52ee..37dbf91 100644
>> --- a/hw/vmport.c
>> +++ b/hw/vmport.c
>> @@ -26,13 +26,15 @@
>>   #include "pc.h"
>>   #include "kvm.h"
>>   #include "qdev.h"
>> +#include "qemu-timer.h"
> Won't be needed, see below.
>
>>   
>>   //#define VMPORT_DEBUG
>>   
>>   #define VMPORT_CMD_GETVERSION 0x0a
>>   #define VMPORT_CMD_GETRAMSIZE 0x14
>> +#define VMPORT_CMD_GETHZ      0x2d
>>   
>> -#define VMPORT_ENTRIES 0x2c
>> +#define VMPORT_ENTRIES 0x2e
>>   #define VMPORT_MAGIC   0x564D5868
>>   
>>   typedef struct _VMPortState
>> @@ -102,6 +104,23 @@ static uint32_t vmport_cmd_ram_size(void *opaque, uint32_t addr)
>>       return ram_size;
>>   }
>>   
>> +static uint32_t vmport_cmd_get_hz(void *opaque, uint32_t addr)
>> +{
>> +    CPUX86State *env = cpu_single_env;
>> +    uint64_t value;
>> +
>> +    value = (uint64_t)env->tsc_khz * 1000;
>> +    if (value) {
>> +        /* apic-frequency (bus speed) */
>> +        env->regs[R_ECX] = (uint32_t)get_ticks_per_sec();
> So this is 1MHz. That happens to be what we return in
> get_ticks_per_sec(), but I don't see the logical relation between both.
> Better set a constant, none of our APIC emulations will change it.
>
>> +        /* High part of tsc-frequency */
>> +        env->regs[R_EBX] = (uint32_t)(value >> 32);
>> +        /* Low part of tsc-frequency */
>> +        return (uint32_t)value;
> EDX is unused by GETHZ? Just wondering if there is spec.
I have not been able to find a SPEC.  Testing on real VMware systems 
showed that EDX is not changed. And the linux kernel ignored EDX output.
>
>> +    } else
>> +        return env->regs[R_EAX];
> Use checkpatch.pl, please.
I did:
     don-760:~/tmp/qemu>./scripts/checkpatch.pl 
outgoing/0001-hw-Add-VMware-s-GETHZ-command.patch
     total: 0 errors, 0 warnings, 46 lines checked

     outgoing/0001-hw-Add-VMware-s-GETHZ-command.patch has no obvious 
style problems and is ready for submission.
Will fix.
>
>> +}
>> +
>>   /* vmmouse helpers */
>>   void vmmouse_get_data(uint32_t *data)
>>   {
>> @@ -141,6 +160,7 @@ static int vmport_initfn(ISADevice *dev)
>>       /* Register some generic port commands */
>>       vmport_register(VMPORT_CMD_GETVERSION, vmport_cmd_get_version, NULL);
>>       vmport_register(VMPORT_CMD_GETRAMSIZE, vmport_cmd_ram_size, NULL);
>> +    vmport_register(VMPORT_CMD_GETHZ, vmport_cmd_get_hz, NULL);
>>       return 0;
>>   }
>>   
>>
> Looks good otherwise.
>
> Jan
>