biscuit

[fair belfry]

https://github.com/sunset-hue/biscuit

[fair belfry]

this is my main problemnow

PHDR is apparently in the lower half of memory when I try to load my "kernel" with limine and I have no idea how to change it

[oblique musk]

using a linker script

[deft mural]

there are example linker scripts in here

https://github.com/jasondyoungberg/limine-rust-template

also limine supports VGA textmode?

[upper quarry]

Bro stole the MIT OS name

[fair belfry]

awww

i liked the name ok 😭

[fair belfry]

pretty sure not so I'm gonna use framebuffers

i'm gonna update that soon

[fair belfry]

tysm

[fair belfry]

UPDATE: got it compiling without any errors, but I haven't implemented framebuffers so there's no output for now

[fair belfry]

I'm gonna implement rn

[fair belfry]

rn I'm writing down GDT related info so I can implement it correctly

ok starting on gdt implementation

[fair belfry]

ok I was confused for a while but I have it I think

i've made code to establish almost every GDT segment

except .tss

so the TSS section needs to be placed where the .tss location is defined in the linker script right

[deft mural]

huh you can place it anywhere, depends on your implementation ig, I don't use any special sections you just want a global variable (static) storing a TSS structure

and your segment should be a pointer to it

[oblique musk]

tss should be per-cpu so each kernel can have a different rsp0 and ist stacks

[deft mural]

yeah but they also need a per CPU GDT for that and they currently didnt design it that way

[fair belfry]

ohh ok

[fair belfry]

I'm going to set up the tss segment a bit later since its a bit more complicated so I'm going to start with IDT

oh wait nvm

to set up an IDT i need to have the tss set up so the gate descriptors can point to an offset in the tss

[fair belfry]

ok I've implemented some assembly from the gdt tutorial for loading the GDT in so now I just need to check if it is actually loaded in

can somebody check my code and see if I'm doing it right

[fair belfry]

oh wait my brain is fried rn

wait I'm confused on what the TSS is supposed to do because I'm in long mode and how to set it up to load in long mode

after tss I can finally move on to IDT

it shouldn't be that difficult to implement at all it's just that I can't quite understand how to set the tss up

[deft mural]

no you don't need it for now

gate descriptors can point to no ist

[fair belfry]

oh

[deft mural]

IST: A 3-bit value which is an offset into the Interrupt Stack Table, which is stored in the Task State Segment. If the bits are all set to zero, the Interrupt Stack Table is not used.

that is the only TSS requiring thing in the IDT

[violet basalt]

also rsp0 is only relevant when switching from ring 3 -> 0 (userspace to kernelspace)

[fair belfry]

ohh

so tss isn't required for me rn

[violet basalt]

you could just do other stuff right now yeah

[fair belfry]

yeah I've set up every GDT segment and I'm probably going to start IDT now

after I finish up the IDT what would u guys say i should do next

[deft mural]

a PMM

and paging

the serial and a println!() implementation would also be helpful if you dont have that already

[fair belfry]

yeah I was thinking about that

[violet basalt]

#curated-resources message

take a look at this

[fair belfry]

starting on idt

[fair belfry]

made almost no progress today 😎

[fair belfry]

i made some progress today

oops

i mean yesterday

[fair belfry]

ok I'm actually gonna make progress today

I'm pushing away the IDT stuff until I get a println implementation

[fallow fiber]

is biscuit a British operating system?

by using this operating system you consent to our use of biscuits.

[fair belfry]

lmao

[fair belfry]

ok I actually started on the pixel drawing