Commit Graph

63 Commits

Author SHA1 Message Date
c90e90bd84 Moving the images from the repo into the disk folder 2022-09-01 16:15:24 +02:00
a5e7fdd07e KERNEL: Physical Page Frame allocation
Rewriting the setup to allow for physical memory allocation again to work.
2022-09-01 16:15:10 +02:00
59ba41f3d2 Multiboot Memory Map get copied to a "safe" place 2022-08-23 21:35:19 +02:00
5051b8903c Divided the kernel into seperate distinct phases
The first stage after GRUB will be Pre-Kernel. This stage will organize the
information we receive from the bootloader. (in our case that will be grub)

The second stage is for now called early_main. The program will at this
point already be running in virtual higher-half / higher-quarter address space.
The goal of the second stage is to set up the kernel in such a way that we are
ready to jump in to usermode.

The third stage is for now called kernel_main. This stage will jump us into
usermode and load the startup programs.

- Added a GRUB entry for tests
- Started writing the pre-kernel stage
- Removed knowledge of multiboot from early_main
- Edited the linkerscript to link variables in pre-kernel to
	lower address space. ( from 1MB and up)
2022-08-22 21:16:34 +02:00
0f0fc9f252 Adding a skeleton for the memory management code
Moved the PMM away from being object orientated as it is just plain annoying
renamed src folder to source
Set timeout to 5 seconds in the grub config
2022-08-21 21:18:53 +02:00
e70f56a005 Improving the memory mapping boot code
Removed the need to map the extra MBI structure in as a seperate pagetable
Renaming / Restructuring the memory folder
2022-08-21 21:15:15 +02:00
560dd64e64 Kernel is working in its full former glory as a higher half kernel 2022-08-19 23:44:38 +02:00
9436e6e033 End of the day cleanup.
* Added symbol files to .gitignore
* Improved text in #PG and #GP handlers
* Added the printing of the multiboot structure address and the magic value
* Added page fault screenshot to readme
2022-08-19 01:05:10 +02:00
d280aa0584 Page faults and protetion faults will now hang with a helpful message
to explain what is going on.

I removed previously set barriers from the code to load
the kernel further.
2022-08-19 00:44:52 +02:00
7d6c823d79 Basic Launch of Higher half kernel
We now can launch the kernel at 0xC0000000 (or 3 GiB mark) with paging enabled.
A lot of early main is currently not executed to keep debugging as simple as possible
during the initial testing of higher half kernel loading.

A lot of the implementation is straight from wiki.osdev.org/Higher_Half_x86_Bare_Bones. Thanks to all the folks
who keep that wiki updated, its really resourceful.
2022-08-18 01:26:49 +02:00
bbfea39c23 Fixing include paths for new structure
Removed non-sensical libc folder from project
2022-08-17 14:57:50 +02:00
3b3e2597a1 Restructering Kernel folder before moving to higher half kernel
The boot up process will be changed somewhat dramatically, therefor a
restructering of the kernel seems as a good starting point.
2022-08-17 14:29:26 +02:00
0b0e37b762 Paging cleanup, more cpu testing and psuedo code for higher half kernel 2022-08-17 14:17:58 +02:00
388ac8e7f9 Added checks to be sure paging is actually enabled on the cpu.
- Made a special assembly file to put CPU check function in. E.G. functions to get the state of
	specific registers

In this case I have created a simple assembly function to get the contents of the CR0 register.
With the help of the c++ preprocessor the value can then be used to check if certains bits are set.
For example to check if the PG (paging) bit is set, indicating that paging is enabled for the
processor.
2022-08-16 19:06:16 +02:00
9172da075a Added identity paging basics
Followed wiki.osdev.org/Setting_Up_Paging
2022-08-15 19:51:22 +02:00
23c68d9863 Setup paging function signatures... Ready to be implemented. 2022-03-18 22:09:04 +01:00
b4cff3e667 Basic block allocation for physical memory allocation.
- 1 block = 4096 bytes : because this will make page fault handling possibly
somewhat easier

- 1 byte in the bitmap = 8 blocks of physical memory

unsure if the allocation is perfect ... guess i'll find out some day if this is actually correct.

The bitmap needs 16kb to keep track of 2gb of physical memory. Seems a decent percentage to me.
2022-02-26 20:55:34 +01:00
7330b81a10 Started definition file for a CMOS driver 2021-12-29 16:28:55 +01:00
97606dbf71 Clean up of debugging logs and new commands.
As this project grows it becomes important to keep things properly organised.
In this commit I've put some effort into making the kernel.cpp file more consise and thus improve its
readability.
Certain parts of the code have gotten their own definition file where before it
was only a header file.

- Moving the Supervisor Terminal into its own definition file.
- Subtracting debugging messages with preprocessor ifdef's
- Time and Date is now not just a header but has its own proper definition file
- Banner is displayed when booting up
- Terminal has a couple new commands

	Commmand		Description
	=================|||||===================================================
	DATE (was TIME)		Displays the curren time, date and ticks
	VERSION			Displays system version information
	MEMORY			Displays memory information
2021-12-29 16:15:18 +01:00
7496299761 Basic Intel Exceptions
Any interrupt thrown for any Intel defined Exception is not only being caught but
displays an appropriate message to the screen.

Changes made in src/kernel/idt/idt.cpp
2021-12-28 19:54:10 +01:00
0d8ef065e0 Interactive supervisor mode
To ease the pain of debuggin I can now interact with the system through a
very simplistic terminal. Hopefully things can be tested more easily by activating
the piece through a simple command. The max characters for a command is 10.

To achieve this I have had to make the following changes.
- Changed IRQ to update a global status variable
- Added a standalone keyboard driver with getKey functions
- Changed the main kernel loop to display a prompt
- Added a strncmp function to the clib/string file
2021-12-28 19:52:48 +01:00
88cc1d75bb Re-enabled interrupts from keyboard, Enabled and configured the PIT to throw interrupts at a regular interval 2021-12-20 21:53:57 +01:00
23ede25ed6 Small changes to reflect renaming in readme.md 2021-11-22 20:04:14 +01:00
ba043ef31b Small improvements on Makefile, TODO.md has been renamed to features.md 2021-11-22 20:01:12 +01:00
88c5196586 Rewritten GDT logic 2021-11-16 21:17:49 +01:00
3a87b74224 Renaming/Moving stuff into a different file structure 2021-11-16 13:57:15 +01:00
32909aaed9 GDT is running again 2021-11-06 21:56:42 +01:00
5fb55367ca Implementation of simplistic physical memory manager 2021-11-06 16:27:13 +01:00
d79fc6e8e2 Split up boot.s into multiple assembly definitions, Started page frame allocator implementation, kterm definition is now considered c plus plus 2021-11-06 14:05:29 +01:00
bdcf9e66f8 Small adjustment in directory structure of memory and bootloader files in kernel 2021-11-02 21:15:00 +01:00
c9b789ed7b Added a bunch of new stuff no time to figure out what's what, No longer any compiler warnings 2021-11-02 21:03:11 +01:00
b4b615ae97 Checked off some todo's 2021-10-23 12:27:13 +01:00
092c5d520d Added option to create an iso 2021-10-23 12:26:15 +01:00
643f2d708b Added emulator options, Added header for VBE driver, Added CPUID function, Added demodisk.img as drive 2021-07-22 22:14:58 +01:00
f2c8b8ac5c Improved multiboot compliance 2021-07-22 20:02:47 +01:00
f48f8072c0 Merge InterruptHandling into MemoryManagement 2021-07-22 19:11:01 +01:00
7409e579c8 Basic keyboard input 2021-07-21 21:31:57 +01:00
04f941a625 Kernel now responding to keyboard interrupts 2021-05-28 22:20:13 +01:00
24a855bb3b Fix up wrong interrupt handler numbers in boot.s 2021-05-28 22:18:50 +01:00
7616ad40ee Moving logo to png format gitea doesn't handle svg format, simplified screenshot inclusion in readme 2021-05-26 20:03:53 +01:00
8ea45d3818 Adding logo properly to README, hopefully this way it show up in preview on gitea 2021-05-26 19:58:34 +01:00
fa67df4bc0 Added an otter logo! I think its so cute 2021-05-26 19:54:59 +01:00
83d220019c Nicer time print 2021-05-22 19:24:29 +01:00
48b65b2276 Kernel now enter continuous time telling mode 2021-05-18 21:14:26 +01:00
e0dfa69df8 Removed itoa and printf from idt 2021-05-18 21:13:14 +01:00
394882ca2e Added CMOS time read function, Added cariage return support to kterm 2021-05-18 21:11:48 +01:00
592db0ebcf More work on interrupt handling, Started timer interrupt implementation, PIC remapped hopefully successfull 2021-05-16 15:53:14 +01:00
nigel
28ac6a05af Interrupts are working.. processor no longer resets 2021-05-12 20:43:15 -04:00
0d0c06ab09 Working on PIC 2021-05-12 23:48:06 +01:00
5e668f5e67 Basics for an proper GDT and IDT 2021-05-12 23:03:00 +01:00