On 03/06/15 at 11:33 PM Paul Menzel paulepanter@users.sourceforge.net wrote:
Dear Felix, dear Varad,
Varad, welcome to coreboot!
Am Freitag, den 06.03.2015, 21:50 +0100 schrieb Felix Held:
I dumped the BIOS binary for a Radeon GPU and am trying to make sense of it using the atombios kernel header [1] - are there any resources on ATOMBIOS internals I can use? I believe the GPU initialization can be done by tracing the dump contents as suggested in this thread [2], but cannot figure how new ATOMBIOS tables would be created and used. I also need to check the coreboot source to plan how this can be implemented.
If you plan to work on native gfx init for AMD, talk to mrnuke; he already did quite some work on that.
Alexandru has already pushed change sets for review [1][2][3]. Additionally he wrote some posts touching this topic, which you can read in the coreboot blog [4].
Additionally there are several threads on this mailing list, where this topic was discussed.
I wish you the best of luck with your application!
Thanks - in that case I would like to work on adding coreboot support to an ARM platform, later adding Tianocore as a payload. Here is my view of the idea, please suggest if I am on the right track:
The board specific lowlevel code would be placed at src/mainboard/<mainboard> and the SoC (gpio, uart, clock, pinmux) initialization at src/soc/<soc>. The implementation details can be taken from the SoC reference manuals, U-Boot source and the mainboard specs.
UEFI would be the second stage loader - the SoC support can be added by extending the existing ArmPkg framework, and the boot flow would look like Reset -> Coreboot lowlevel init -> UEFI Pre-PI* -> UEFI DXE.
Can the UEFI HOBs be constructed by coreboot so that Pre-PI can be removed? I also need some help figuring where libpayload fits in - Tianocore has its own implementation of C library routines (edk2/StdLib), and once UEFI takes control, these can directly be used by the FD.
I am tracing the existing ARM code. Which mainboard would be the preferred target? Also, please suggest any 'easy' patches I could send in to get comfortable with the development process.
Thanks, Varad
Thanks,
Paul
[1] http://review.coreboot.org/8281 [2] http://review.coreboot.org/8281 [3] http://review.coreboot.org/8281 [4] http://blogs.coreboot.org/blog/author/mrnuke/