From mboxrd@z Thu Jan  1 00:00:00 1970
From: Stephen Warren <swarren@wwwdotorg.org>
Date: Mon, 13 Jul 2015 22:52:58 -0600
Subject: [U-Boot] [PATCH 00/20] arm: rpi: Enable USB and Ethernet driver
 model Raspberry Pi
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 <55A0AAD3.2050302@wwwdotorg.org>
 <CAPnjgZ1VArrhqY6+sNgCcj1PMCxvwyh2Uv6YgvJRCo+gv1TDng@mail.gmail.com>
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On 07/11/2015 08:04 AM, Simon Glass wrote:
> Hi Stephen,
> 
> On 10 July 2015 at 23:34, Stephen Warren <swarren@wwwdotorg.org> wrote:
>> On 07/07/2015 08:53 PM, Simon Glass wrote:
>>> Raspberry Pi uses a DWC2 USB controller and a SMSC USB Ethernet adaptor.
>>> Neither of these currently support driver model.
>>>
>>> This series does the following:
>>> - Move Raspberry Pi to use device tree control (u-boot-dtb.bin instead of
>>>      u-boot.bin)
>>
>> I'd strongly prefer not to do this. For one thing, it means we'd need
>> different U-Boot builds for each of the different RPi models, and we
>> currently don't need that (or perhaps we require users to create their
>> own u-boot-dtb.bin by choosing the right DTB to append). If it
> 
> Why does device tree change how things work now? The get_board_rev()
> function currently deals with this. It doesn't look like rpi_board_rev
> is used anywhere else.

Without a DT, the code is free to make all the board-rev-specific
decisions at run-time without external influence.

With a DT, we either have to:

a) Pick the DT for one particular board and use that everywhere, even if
it's incorrect for the actual board in use.

b) Build a different U-Boot + DTB image for each board-rev, and put the
correct one on the SD card.

Neither of those options seem like a good idea to me.