[U-Boot] [PATCH] sunxi: use CONFIG_DEFAULT_FDT_FILE everywhere

[Martin Kelly]

(ping Jagan)

On 06/06/2018 10:51 AM, Martin Kelly wrote:
> On 06/06/2018 07:58 AM, Maxime Ripard wrote:
>> On Mon, Jun 04, 2018 at 11:15:34AM -0700, Martin Kelly wrote:
>>> [snip as the thread is getting long]
>>>
>>> On 06/04/2018 01:21 AM, Maxime Ripard wrote:
>>>> On Fri, Jun 01, 2018 at 10:16:32AM -0700, Martin Kelly wrote:
>>>>> On 06/01/2018 04:05 AM, Maxime Ripard wrote:
>>>>>
>>>>> I can see the issues with new defconfigs, but I'm not sure if it 
>>>>> will really
>>>>> be that bad. If we apply this patch against sunxi master, then 
>>>>> shouldn't new
>>>>> patches get tested and rebased against it? In that case, if they 
>>>>> have not
>>>>> set DEFAULT_FDT_FILE, it will default to "", the boards won't boot, 
>>>>> and the
>>>>> mistake must be fixed prior to merging.
>>>>
>>>> Unless one has tested it with a version prior to your patch, and sends
>>>> it. Not a lot of people are testing with the next branch in the
>>>> various trees.
>>>>
>>>>> Alternatively if we add the Kconfig boolean, we need to worry about 
>>>>> what
>>>>> happens when people have DEFAULT_FDT_FILE set already. I guess we 
>>>>> would need
>>>>> to default the new Kconfig boolean to be custom in order to keep those
>>>>> configs from breaking. But if we do that, sunxi will break by 
>>>>> default (since
>>>>> sunxi configs don't have the value set).
>>>>>
>>>>> What would you suggest the default value of the new boolean to be?
>>>>
>>>> config DEFAULT_FDT_FILE_USE_DEFAULT_DEVICE_TREE
>>>>     bool "whatever"
>>>>     default y if ARCH_ROCKCHIP
>>>>     default y if ARCH_SUNXI
>>>>
>>>> and in the headers
>>>>
>>>> #ifdef CONFIG_DEFAULT_FDT_FILE_USE_DEFAULT_DEVICE_TREE
>>>> #define CONFIG_DEFAULT_FDT_FILE CONFIG_DEFAULT_DEVICE_TREE ".dtb"
>>>> #endif
>>>>
>>>> And that's done.
>>>
>>> I didn't know Kconfig can set different default values for each
>>> architecture like that; that does indeed solve the problem. However,
>>> I don't think it's a good idea to have sunxi use an alternate
>>> mechanism than the other boards.
>>>
>>> To be clear, are you proposing a general config option that would
>>> apply to every board? In that case, the header logic would be in a
>>> global header rather than a board-specific one.
>>
>> Yes, that's what I had in mind.
>>
>> Maxime
>>
> 
> OK, I can see the merits of that, though I think there's tradeoffs both 
> ways.
> 
> Before I go ahead with a patch, Jagan: which approach would you prefer?

Jagan, do you prefer Maxime's proposed approach, or my original patch? I 
am happy to go either way but want to confirm before proceeding.