Re: [PATCH 5/5] arm: boot: store ATAGs structure into DT "/chosen/linux,atags" entry

[Frank Rowand <frowand.list@gmail.com>]

On 11/28/2015 9:34 AM, Nicolas Pitre wrote:
> On Sat, 28 Nov 2015, Russell King - ARM Linux wrote:
> 
>> On Fri, Nov 27, 2015 at 06:28:50PM -0500, Nicolas Pitre wrote:
>>> On Fri, 27 Nov 2015, Arnd Bergmann wrote:
>>>
>>>> I don't mind creating the /proc/atags compatibility hack from the kernel
>>>> for a DT based N700 kernel, as long as we limit it as much as we can
>>>> to the machines that need it. Leaving a board file for the N700 in place
>>>> that contains the procfs code (and not much more) seems reasonable
>>>> here, as we are talking about a board specific hack and the whole point
>>>> appears to be running unmodified user space.
>>>>
>>>> Regarding how to get the data into the kernel in the first place, my
>>>> preferred choice would still be to have an intermediate bootloader
>>>> such as pxa-impedance-matcher, but I won't complain if others are
>>>> happy enough about putting it into the ATAGS compat code we already
>>>> have, as long as it's limited to the boards we know need it.
>>>
>>> Assuming you have a N700 board file for special procfs code, then why 
>>> not getting at the atags in memory where the bootloader has put them 
>>> directly from that same board file? This way it'll really be limited to 
>>> the board we know needs it and the special exception will be contained 
>>> to that one file.  Amongst the machine specific hooks, there is one that 
>>> gets invoked early during boot before those atags are overwritten.
>>
>> I've already suggested that.
> 
> Good. And Arnd likes the idea too. So we might be converging at last 
> which is a good thing.

It makes me happy too.

-Frank