Hi, On 17 February 2016 at 04:00, Belisko Marek <marek.beli...@gmail.com> wrote: > Hi Simon, > > > On Thu, Jan 28, 2016 at 5:39 PM, Simon Glass <s...@chromium.org> wrote: >> We need a way to support more than one board per binary in U-Boot with >> device tree. Various methods have been discussed. The one that seems to make >> the most sense is to adjust SPL so that it can load a FIT which contains >> U-Boot and several device tree binaries. This is how things with with Linux: >> load a FIT and select the correct device tree to pass to Linux. > Some time ago I rise question [0] to load FIT kernel directly in SPL > using falcon mode. > I did look at your patches and I have a feeling that with small > adaptions it should be possible? > Am I right or it's impossible? (Trying to use it on am33xx boards). Many > thanks.
Yes it should be possible. You will probably need to modify the device tree before booting Linux. In this case however I am not really using the full existing FIT code. It would be easier to use it and it is possible to build full FIT support in SPL. I did it for a project a few years ago but did not upstream it. It does add a bit to the size though. Regards, Simon >> >> This series: >> >> - Adjusts the build system to optionally build a u-boot.img in FIT format >> that includes the U-Boot binary and >1 device tree files >> - Adjusts SPL to support loading this >> - Adds a way for SPL to determine which device tree to select (by calling a >> board-specific function) >> - Adjusts SPL to pass this selected device tree to U-Boot when it starts >> >> It would be painful to require an .its file for each board just to support >> this feature. In any case various people have commented that it would be >> nice not to have to write this file in general. Therefore, this series >> enhances mkimage to automatically generate a FIT without a .its file. So far >> it understands how to add a main image and a number of device tree files. It >> does not support hashing or verified boot as yet. >> >> One problem with the FIT format as it stands is that all the data is inline. >> This means that the entire file must be read in order to figure out what >> device-tree files are available. It is then possible to copy the images into >> place. >> >> This is not really suitable for SPL since copying can be slow, and reading >> unnecessary data would make the FIT format less efficient than the legacy >> format. >> >> Therefore this series adds a new feature to FIT which allows the images to >> be stored immediately after the FIT itself ends. This makes the FIT very >> small. It can be read quickly and in its entirety. Then the images can be >> loaded one by one as needed. This allows SPL to support FITs containing lots >> of images very efficiently. >> >> To achieve this, mkimage is enhanced to convert between the 'normal' and >> 'external' version of a FIT file. The latter is only used for the SPL loader. >> The main difference is that viewing an 'external' FIT will not show the >> contents of each image. >> >> This series also includes a few other tidy-ups, such as moving mkimage's >> tricky argument-processing code to use getopt(). >> >> NOTE: There are a few problems remaining with the Kconfig conversion. I'm >> still fiddling with this but thought it best to send this series out for >> comment in the meantime. >> >> This series is available at u-boot-fdt/spl-working. >> > > [0] - http://lists.denx.de/pipermail/u-boot/2015-February/203938.html >> >> >> _______________________________________________ >> U-Boot mailing list >> U-Boot@lists.denx.de >> http://lists.denx.de/mailman/listinfo/u-boot > > > BR, > > marek > > -- > as simple and primitive as possible > ------------------------------------------------- > Marek Belisko - OPEN-NANDRA > Freelance Developer > > Ruska Nova Ves 219 | Presov, 08005 Slovak Republic > Tel: +421 915 052 184 > skype: marekwhite > twitter: #opennandra > web: http://open-nandra.com _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
