Re: [Qemu-devel] [Qemu-ppc] [PATCH 2/2] Add Enhanced Three-Speed Ethernet Controller (eTSEC)

[Fabien Chouteau]

On 07/16/2013 06:54 PM, Scott Wood wrote:
> On 07/16/2013 11:15:51 AM, Fabien Chouteau wrote:
>> On 07/16/2013 05:37 PM, Alexander Graf wrote:
>> > On 07/16/2013 05:28 PM, Fabien Chouteau wrote:
>> >> On 07/16/2013 04:06 AM, Scott Wood wrote:
>> >>> On 07/10/2013 12:10:02 PM, Fabien Chouteau wrote:
>> >>>> This implementation doesn't include ring priority, TCP/IP Off-Load, QoS.
>> >>>>
>> >>>> Signed-off-by: Fabien Chouteau<address@hidden>
>> >>>  From the code comments I gather this has been tested on VxWorks.  Has it
>> >>> been tested on Linux, or anywhere else?
>> >>>
>> >> You're right, as I said in the cover letter, this has only been tested on 
>> >> vxWorks.
>> >
>> > Could you please give it a try? IIRC eTSEC support should be in upstream 
>> > Linux.
>> >
>>
>> I don't have time for that. As I said in the cover letter, I submit this
>> patch for those interested in eTSEC, but I won't be able to test/fix it
>> for Linux.
> 
> Could you please at least document more fully the known limitations, such as 
> "I'm only interested in 32bits address spaces"?
>

I will, but this device is very complex and I don't even know all the
limitation of my implementation ;)

>> >>>> +    /* ring_base = (etsec->regs[RBASEH].value&  0xF)<<  32; */
>> >>>> +    ring_base     += etsec->regs[RBASE0 + ring_nbr].value&  ~0x7;
>> >>>> +    start_bd_addr  = bd_addr = etsec->regs[RBPTR0 + ring_nbr].value&  
>> >>>> ~0x7;
>> >>> What about RBDBPH (upper bits of physical address)?  Likewise for TX.
>> >>>
>> >> I'm only interested in 32bits address spaces, so RBASEH, TBASEH, RBDBPH 
>> >> or TBDBPH.
>> >
>> > Why? I thought e500mc and above can access more than 32bits of physical 
>> > address space?
>>
>> Yes but this is not emulated by QEMU, right? sizeof (hwaddr) for
>> qemu-system-ppc is 8...
> 
> 36bit physical is emulated by QEMU.  Currently we put CCSR in a place that 
> would make it difficult to use memory above 4G, but that should change at 
> some point.


But hwaddr is 32 bits, how could you call cpu_physical_memory_read()? to
a 36bits address?

Regards,

-- 
Fabien Chouteau