Commit Graph

17 Commits

Author SHA1 Message Date
Eric-Paul Ickhorn 3a778fee44
Add scripts for running bootloader and memdumping
This commit adds two scripts: One for running the bootloader using
Qemu, and one for dumping the memory used by the bootloader for
debugging purposes.
2024-07-19 01:51:28 +02:00
Eric-Paul Ickhorn f573f49874
Fix GDT error offsetting memory by some bytes
The error in the GDT caused the whole memory space to be offset by
128B or 256B (It's not entirely sure which one of those). This was
only made visible by later changes, but now it's fixed.
2024-07-19 00:12:52 +02:00
Eric-Paul Ickhorn a72a41c3ac
Change final bootsector jump to be a near jump
This commit changes the final jump from the bootsector to the second
stage (the partition which gets loaded completely) to be a near jump.
That's important to keep consistency with protected mode.
2024-07-07 13:43:07 +02:00
Eric-Paul Ickhorn 44ca45e8f1
Finish up GDT, get linear address space working
The GDT is now finally set and produces a linear address space.
Execution continues at 'stage2_true_entry'.
2024-07-06 00:12:07 +02:00
Eric-Paul Ickhorn fa818435a2
Add .gitignore with binaries and some folders
This commit adds a .gitignore file which includes a few common
binary file extensions, dumps, the build-script's working folder,
a private folder for convenience and an ignore for the VSCode
editor's configuration folder.
2024-07-06 00:12:06 +02:00
Eric-Paul Ickhorn 0d49245a60
Delete GDT-related files
This commit deletes the gdt.asm for the i386 architecture as it was
quite buggy in that state. In a short while, the real GDT code which
works is going to be committed.
2024-07-06 00:12:06 +02:00
Eric-Paul Ickhorn 993864e364
Save progess, then delete GDT for rewrite
This commit saves the progress made on the GDT; the files are deleted
quickly thereafter as the code was quite buggy.
2024-07-06 00:12:06 +02:00
Eric-Paul Ickhorn 83eb29d55c
Try to fix GDT; unsuccessful
This commit just existed because of a misunderstanding leading to the
belief that the GDT was finally working; it wasn't though.
2024-07-06 00:12:06 +02:00
Eric-Paul Ickhorn 4a835a0ece
Add private, build and vscode folder to .gitignore
The private folder is for convenience, for putting some files away and
for own TODO lists; generally for data which is related to the project
but shouldn't be committed.

The build folder contains intermediate/object files for building the
different stages; it should be ignored explicitly, even though the
file ending of all files marks the folder as ignored implicitly.
2024-07-06 00:12:06 +02:00
Eric-Paul Ickhorn 776da2f85a
Add README.md for loader on i386
This commit adds a README.md file for the loader partition in the i386
architecture version. The README contains basic information about what
the loader partition has to do and to some degree on how it should be
accomplishing those tasks.

It is just general information which can be useful to have for looking
information up after some time.
2024-07-06 00:12:06 +02:00
Eric-Paul Ickhorn 3a2518ca8f
Add build script
This commit adds a build script for the loader partition. Currently,
it is very simplistic, but it works for assembling the entry.asm,
which in turn includes all other files.
2024-07-06 00:11:14 +02:00
Eric-Paul Ickhorn 5180348c39
Add stage 2 loader entry point
This commit adds the entry point for the second stage of the loader.
It currently doesn't contain a lot of code, but it will have to expand
in the next bit of time.
2024-07-06 00:08:57 +02:00
Eric-Paul Ickhorn d773a8f9e2
Add memory utilities and math utils
This commit adds the well known primitive memory functions:

- Copy Memory
- Compare Memory for being equal
- Set Memory to a value

It also adds a math utility file at the according location.
2024-07-06 00:07:08 +02:00
Eric-Paul Ickhorn c3f2c7fbfc
Intermediate commit to add GDT
In this commit, it was tried to set a linear GDT. It didn't work; but
in the future, it will.
2024-07-06 00:05:17 +02:00
Eric-Paul Ickhorn 94a228b278
Add A20 line check
This commit adds a check for whether the A20 line is usable; checking
whether more than one megabyte of RAM can be used. If it isn't usable,
it currently isn't activated, but rather, the boot process is stopped.
2024-07-06 00:03:48 +02:00
Eric-Paul Ickhorn aa09696218
Add .gitignore with binary executable files
This commit adds a basic .gitignore which only contains machine code
file endings; files which shouldn't be committed as they're better to
be distributed in other ways.
2024-07-06 00:02:38 +02:00
Eric-Paul Ickhorn 757457d456
addition(bootsector) 2024-06-14 13:26:54 +02:00