lkml.org 
[lkml]   [2020]   [Sep]   [30]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: [PATCH v3 2/3] iommu/tegra-smmu: Rework .probe_device and .attach_dev
From
Date
01.10.2020 00:32, Nicolin Chen пишет:
> On Thu, Oct 01, 2020 at 12:24:25AM +0300, Dmitry Osipenko wrote:
>> ...
>>>> It looks to me like the only reason why you need this new global API is
>>>> because PCI devices may not have a device tree node with a phandle to
>>>> the IOMMU. However, SMMU support for PCI will only be enabled if the
>>>> root complex has an iommus property, right? In that case, can't we
>>>> simply do something like this:
>>>>
>>>> if (dev_is_pci(dev))
>>>> np = find_host_bridge(dev)->of_node;
>>>> else
>>>> np = dev->of_node;
>>>>
>>>> ? I'm not sure exactly what find_host_bridge() is called, but I'm pretty
>>>> sure that exists.
>>>>
>>>> Once we have that we can still iterate over the iommus property and do
>>>> not need to rely on this global variable.
>>>
>>> I agree that it'd work. But I was hoping to simplify the code
>>> here if it's possible. Looks like we have an argument on this
>>> so I will choose to go with your suggestion above for now.
>>
>> This patch removed more lines than were added. If this will be opposite
>> for the Thierry's suggestion, then it's probably not a great suggestion.
>
> Sorry, I don't quite understand this comments. Would you please
> elaborate what's this "it" being "not a great suggestion"?
>

I meant that you should try to implement Thierry's solution, but if the
end result will be worse than the current patch, then you shouldn't make
a v4, but get back to this discussion in order to choose the best option
and make everyone agree on it.

\
 
 \ /
  Last update: 2020-09-30 23:57    [W:0.581 / U:0.140 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site