On Fri, May 4, 2018, 10:38 PM Simon Glass <s...@chromium.org> wrote: > Hi, > > On 1 May 2018 at 04:52, Ramon Fried <ramon.fr...@gmail.com> wrote: > > On Tue, May 1, 2018 at 12:20 PM, Alex Deymo <dey...@google.com> wrote: > >> Hi Ramon, > >> > >> What "header_version" is the boot image you have? The > >> include/android_image.h in U-Boot is a little bit old so it only > defines the > >> v0 format. The "unused" field in v0 was renamed to "header_version" > where 0 > >> means v0. The v1 adds a few more fields, including a DTB/DTBO for > *recovery* > >> mode. > >> See > >> > https://android.googlesource.com/platform/system/core/+/master/mkbootimg/include/bootimg/bootimg.h > >> > > Yes, the U-boot has the v0 version. > > > >> Having multiple DTs and picking one or merge overlays at runtime is a > >> reasonable thing and there's some documentation in AOSP on how to do it > in > >> Android: https://source.android.com/devices/architecture/dto/multiple > (and > >> other sections around it). There are some options on where to store > these > >> and even a supported format for placing multiple .dtbo in a single > "dtbo" > >> partition (but appending multiple DTBs at the end of the kernel is not > one > >> of these). > >> > >> Which are the "seconday" fields you are referring to? > > > > uint32_t second_size; /* size in bytes */ > > uint32_t second_addr; /* physical load addr */ > > > > In > https://android.googlesource.com/platform/system/core/+/master/mkbootimg/include/bootimg/bootimg.h > >> > >> I'm not familiar with the Dragonboard images, but it looks like they > just > >> extended this over the reserved space in a different way. Maybe you can > >> convert the header to the newer format, but that still requires work in > >> U-Boot to support the new format. > > I'm willing to do it, I just want to get some approval from > > maintainers before I dive in. > > > > Thanks, > > Ramon > >> > >> Regards, > >> Alex > >> > >> > >> Le lun. 30 avr. 2018 à 16:17, Ramon Fried <ramon.fr...@gmail.com> a > écrit : > >>> > >>> Hi all. > >>> I'm currently adding support for Qualcomm Dragonboards to U-boot as a > >>> primary bootloader without chain-loading using LK which is currently > >>> already supported in mainline U-boot. > >>> > >>> Qualcomm Android images are regular android images where the DTB's are > >>> appended to the image. Qualcomm used the "unused" field in the image > >>> header to populate the size of the DTB *. > >>> > >>> I'm looking for a more standard version for supporting these kind of > >>> images. > >>> Currently, to boot these images, you must provide DTB somewhere in mem > >>> and provide it as argument to bootm for instance. > >>> > >>> My goal is to add support that U-boot will parse the image, see that > >>> the DTB is included and use that as the FDT automatically. > >>> > >>> I'm looking at the "secondary" fields which are currently not used as > >>> a valid option to point to the DTB and it's size. > >>> > >>> Do you know if someone is working on something similar, or do you have > >>> any suggestions for the right approach to this issue ? > > Does every vendor just do its own thing, or is there a standard header > structure? > I don't know. I'm familiar only with Qualcomm way. Not sure about the rest.
> > How can we detect multiple incompatible options? Just by the machine > architecture? > Qualcomm is using the unused fields in version 1 of Android boot header. I guess that ifdef in the source code is the only way. > > Can we just use FIT perhaps? > Of course we can, I already booted successfully with FIT. But it will require users to repackage their kernel boot image. > >>> > >>> Thanks, > >>> Ramon > >>> > >>> * - Actually, Qualcomm appends a pack of DTBs with offset table and > >>> chooses the right DTB in runtime. > >>> _______________________________________________ > >>> U-Boot mailing list > >>> U-Boot@lists.denx.de > >>> https://lists.denx.de/listinfo/u-boot > > Regards, > Simon > _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot
