On 4 March 2015 at 16:17, Siarhei Siamashka <siarhei.siamas...@gmail.com> wrote: > On Tue, 03 Mar 2015 08:17:56 +0000 > Ian Campbell <ijc+ub...@hellion.org.uk> wrote: > >> On Mon, 2015-03-02 at 00:07 +0200, Siarhei Siamashka wrote: >> > Just one suggestion. It would be really nice if the Debian installer >> > could present itself on all the available consoles, so that the user >> > can use any of them for providing input to the installer. >> >> There is some reason why d-i doesn't do this by default. I think it's to >> do with bricking or otherwise interfering with devices attached to >> serial ports e.g I think Braille terminals were mentioned, but I suppose >> any random device might not like getting random strings of characters. > > There could be perhaps a fake kernel cmdline option to specify the > exact list of consoles to be used by the Debian installer? > >> > Otherwise there will be a need to provide separate SD card images for >> > the HDMI console (for the Raspberry Pi wannable competitors), the UART >> > serial console (A10/A20 development boards without HDMI) and the USB OTG >> > serial gadget console (for the tablets without HDMI). Instead of just >> > having only a single SD card image to handle everything automatically. >> >> I've backported DT the /chosen/stdout-path support to the kernel a while >> ago and I thought together with Hans' u-boot patches to populate this >> field with the right thing then console selection would Just Work(tm). > > I need to check this new feature myself, especially whether it can do > user input handling. > >> At least for HDMI vs. UART since I'm not quite sure how the OTG gadget >> console is presented to Linux and whether it falls into this stuff >> correctly. > > It should be seen as just one more /dev/tty* entry (maybe USB or ACM). > > My original plan from > > http://lists.denx.de/pipermail/u-boot/2015-January/202306.html > > was to make the bootable SD card just drop into the FEL mode in the > case if an A13/A23 SoC is detected or if there is no HDMI monitor > connected. Then a custom application running on a desktop PC could > upload a custom SPL for the only purpose of identifying the DRAM size > and bus width. Then present a choice of the possibly matching devices > to the user, boot the system via FEL, run hardware reliability tests > and move on to preparing the rootfs. > > But with the Debian installer, this becomes somewhat more difficult. > Because we need a way of handling user input during the installation > (for the language selection, time zone, and other things).
For things selectable from a menu it might be possible to use the volume and power keys as the Android recovery does. Driver for the power key is already in u-boot. It's just not hooked up to provide input. > > However with the new USB OTG code from Hans hopefully coming into the > Linux kernel, we can have everything much easier and more unified :-) > Basically, the serial port over USB should work fine even in Windows > (at least it works for the Arduino people): > > http://arduino.cc/en/Guide/Windows > > And because the BROM is able to use USB OTG for the FEL mode on all > sunxi devices, the serial console over USB should also work in a > generic image without any special device dependent configuration. I pretty much use only the OTG port when I boot GNU/Linux on a tablet. yes, I can get display output but any input has to come over OTG so I use ethernet gadget and ssh. That also happens to cover downloading stuff in case the WiFi chipset is not supported. I have yet to see an Allwinner tablet with supported touchscreen. Thanks Michal _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot