[PATCH v11 08/10] dt, numa: Add NUMA dt binding implementation.

Rob Herring
2016-03-01T16:47:19Z

On Thu, Feb 25, 2016 at 7:26 PM, David Daney <ddaney@caviumnetworks.com> wrote:
> On 02/23/2016 11:36 AM, Rob Herring wrote:
>>
>> On Fri, Feb 19, 2016 at 05:13:17PM -0800, David Daney wrote:
>>>
>>> From: Ganapatrao Kulkarni <gkulkarni@caviumnetworks.com>
>>>
>>> ADD device tree node parsing for NUMA topology using device
>>> "numa-node-id" property distance-map.
>>
>>
>> I still want an adequate explanation why NUMA setup cannot be done with
>> an unflattened tree. PowerPC manages to do that and should have a
>> similar init flow being memblock based, so I would expect arm64 can too.
>
>
> Many things could be done. Really, we want to know what *should* be done.
>
> In the context of the current arm64 memory initialization we (more or less)
> do:
>
> 1) early_init_fdt_scan_reserved_mem();
> 2) memory_present()
> 3) sparse_init()
> 4) other things
> 5) unflatten_device_tree()
>
> We are already reading information out of the FDT at #1.
>
> This patch set adds a step between 1 and 2 where we read NUMA information
> out of the FDT.

The dependency on unflattening is that memblock is up and we can
allocate a chunk from it. Isn't that dependency met by step 1 or is
there a dependency on sparsemem (or something else)?

Rob