Basics of x86 assembly (AT&T syntax)

Published at May 17, 2018 ·  12 min read

Nowadays, application of programming in assembly language is very small. Writing production code in assembly may be found in the most demanding tasks in embedded. Even in modern firmware (coreboot, EDK2) most of the code is written in C. Honesly, that’s quite undestandable, assembly code isn’t easy to read nor write and some state that it’s no longer needed to be known. In my opinion, that’s far from the truth....

Categories: programming

The art of disassembly

Published at April 27, 2018 ·  12 min read

Probably there was never a programming language that would fascinate me as much as assembly. In fact, it was my second “real language” (after Pascal/Delphi and DOS batch) and the first one I would really understand. Of course, the internals of protected mode initialization was too much for 15-year-old and I finally moved to C and *nix shell. Anyway, I always liked the feeling that I know what I’m really doing but more complex languages are needed nowadays....

Categories: programming

Building UEFI based firmware on MinnowBoard

Published at March 28, 2018 ·  8 min read

Building coreboot on well supported platform such as Bay Trail is quite straightforward task, however we need to remember about some things in order to have coreboot working. First of all we need to provide up-to-date microcode and FSP (Firmware Support Package), which are not included in coreboot source tree and coreboot build system won’t complain about it. Second thing is that Bay Trail has TXE firmware on the same ROM as boot firmware so we have to make sure that we won’t corrupt it because it would brick the platform....

Categories: firmware