From mboxrd@z Thu Jan 1 00:00:00 1970 From: Simon Glass Date: Tue, 14 Jul 2015 09:44:59 -0600 Subject: [U-Boot] [PATCH 00/20] arm: rpi: Enable USB and Ethernet driver model Raspberry Pi In-Reply-To: <55A495AA.6080609@wwwdotorg.org> References: <1436324032-17931-1-git-send-email-sjg@chromium.org> <55A0AAD3.2050302@wwwdotorg.org> <55A495AA.6080609@wwwdotorg.org> Message-ID: List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi Stephen, On 13 July 2015 at 22:52, Stephen Warren wrote: > On 07/11/2015 08:04 AM, Simon Glass wrote: >> Hi Stephen, >> >> On 10 July 2015 at 23:34, Stephen Warren 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. How about: c) Leave the code as is, and not add a whole lot more device tree files. After all the kernel only has files for rpi and rpi_2. Why should we add one for each variant? If you don't want to do it, why do it? Regards, Simon