Re: [PATCH v2 1/4] pci: iProc: define Broadcom iProc PCIe binding

Arend van Spriel
2014-12-14T09:48:14Z

On 12/13/14 20:46, Arnd Bergmann wrote:
> On Saturday 13 December 2014 11:05:52 Arend van Spriel wrote:
>>
>> Makes sense. I think that is what Hauke meant by "adding
>> additional support for registering to bcma". So the discovery info is a
>> piece of read-only memory in the chip. Its address is stored in the
>> chipcommon core register space. BCMA parses that memory blob resulting
>> in a list of cores which register address info. We could add DT support
>> in BCMA matching the compatible string and register a core for it.
>
> Ah, interesting idea. That would mirror what we do for drivers/amba,
> I like the idea.

+ Rafal

Let's explore this. Although I don't have the iProc hardware to verify it.

>> However, apart from the discovery info a "discoverable ARM AXI" chip has
>> a register space per core that provides common procedures like
>> enable/disable, reset, core status, which are implemented in BCMA. I am
>> not seeing that register space in the DT examples so I guess this IP
>> block is not there for iProc chips.
>
> I wouldn't draw conclusions from the absence of some node. Maybe these
> registers are present but just not used by the original BSP.

I do not intend to. We have raised the question internally to iProc chip
designers.

Regards,
Arend