[U-Boot] [PATCH] pci: Support parsing PCI controller DT subnodes

Marek Vasut marek.vasut at gmail.com
Mon Aug 13 13:43:56 UTC 2018


On 08/13/2018 04:07 AM, Bin Meng wrote:

[...]

>>>>> Sorry this is terribly wrong. Imagine someone
>>>>> writes another OS, and all he has is the device tree spec. He follows
>>>>> the spec and writes some codes to parse a valid DT, and it's done. How
>>>>> his OS makes use of the DT is his design decision and none of the
>>>>> device tree specs has hard requiement on it. Of course, using exact
>>>>> the same DT as Linux is nice-to-have feature but that's not the reason
>>>>> to attack has OS has bugs to parse DT.
>>>>
>>>> There is supposed to be only one DT for all the OSes, which has nothing
>>>> to do with Linux or U-Boot or any of those. If some OS cannot parse an
>>>> valid DT completely, then it's lacking.
>>>
>>> I really don't understand such obsessiveness.
>>
>> I can say the same thing, I don't understand why you're trying so hard
>> to protect the lacking PCI DT parsing code in U-Boot. That is the part
>> which needs to be fixed.
>>
>>> Currently there is NO
>>> ALL OSes. There is ONLY Linux.
>>
>> Er, no. You forgot all the BSDs, SunOS and possibly a few others I forgot.
> 
> In fact, I didn't. I compared many dts files in BSD source codes
> against the dts files in Linux tree (with the same name, for the same
> board), and they _are_ unsurprisingly different. Some of nodes indeed
> have "compatible" string while the other one does not, which reveals
> the truth that what you kept saying all OSes should use exactly the
> same DT is purely wrong. You are too Linux-centric.

Contradiction (!truth) implies anything, that's logic 101.

>>> What you kept talking about is the
>>> reference implementation from Linux. You need convince me adding a
>>> compatible string to the USB node makes the DT invalid. If you admit
>>> adding "compatible" is perfectly OK, then per your theory Linux should
>>> handle it without any problems.
>>
>> I think I lost you here. I won't pollute this thread with even more
>> crap. USB is a probable bus, just like PCI, you don't need compatible
>> strings there either.
>>
> 
> Didn't you see the "PCI Bus Binding" spec? It's a spec existing for years.
> 
>>> Next step is to upstream the DT
>>> changes to Linux kernel, then sync the changes to U-Boot to satisfy
>>> this obsession - using exactly the same DT as Linux.
>>
>> This is not gonna happen.
>>
>> Sorry, you're really just wasting my time with this foolishness. If
>> U-Boot cannot parse valid DT bindings while other OSes can, U-Boot is
>> broken and must be fixed. So far I only see you attacking this patch and
>> trying to pull in everything you can do avoid accepting this patch or
>> providing a better alternative. This is not a constructive discussion,
>> so I stop here.
>>
> 
> The fix in this patch is purely hack, period.

So while you're constantly yelling "hack" "hack" here, I don't see any
constructive feedback. Can you provide any ?

-- 
Best regards,
Marek Vasut


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