reduced complexity on master branch for now as i setup for gdt things

This commit is contained in:
shockrah 2019-10-09 15:26:54 -07:00
parent 9e7effcc7f
commit ec9cd34dc6
6 changed files with 23 additions and 58 deletions

5
gdt.s Normal file
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@ -0,0 +1,5 @@
global load_gdt
; lgdt can only be used from assembly so here we are
load_gdt:
lgdt [eax]

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@ -10,6 +10,8 @@ CHECKSUM equ -MAGIC_NUMBER
; size in bytes of stack
KERNEL_STACK_SIZE equ 4096
extern test_dispatcher
extern load_gdt
extern struct example
section .text
; align all instructions to 4 byte boundary by the x86 instruction set law
@ -19,7 +21,10 @@ align 4
dd FLAGS
dd CHECKSUM
; sets up our gdt and segment selectors for later use
loader:
call load_gdt
call test_dispatcher
.loop:

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@ -33,7 +33,7 @@ os.iso: kernel.elf
$(ASM) $(AFLAGS) $< -o $@
# Building C objecets
core/%.o: %.c
%.o: %.c
$(CC) $(CFLAGS) $< -o $@
# Running (no recipes called)

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@ -1,4 +1,4 @@
; Helpers for frame buffer which pretty much have to to be
; Helpers for serial ports which pretty much have to to be
; written in asm
global serialport_write_byte

63
stlio.c
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@ -31,65 +31,16 @@ u32 read(const u32 n) {
return n;
}
char* tohex(u32* data, u32 size) {
static char ret[19] = {'\0'}; // 8 bytes + \0
ret[0] = '0'; ret[1] = 'x';
const char* map = "0123456789abcdef"; // muh 'tism
switch(size) {
// (unsigned)char/u8/s8
case (1): {
u8 idx;
u8 val = (u8)*data;
for(u32 i = 0; i<2; i++ ) {
idx = val & 0x0f;
ret[19-i] = map[idx];
vall >>= 4;
}
break;
}
// s16/u16
case (2): {
for(u32 i = 0; i<4; i++) {
}
break;
}
// s32/u64
case (4): {
break;
}
// s64/u64
case (8): {
break;
}
default: return "Bad-Size";
}
return "sadf";
}
void printf(char* fmt) {
u32 i;
// Variadic fuller version of print on seperate branch but its nowhere near stable/ready/working
u32 size = strlen(fmt);
for(i = 0; i < size;i++) {
char c = fmt[i];
switch(c) {
case '\n': {
frame_buffer_newline();
break;
}
case '%': {
/* only do something if the situation calls for it
* NOTE: this call might not do anything interesting
*/
if((i+1) < size) {
write_char(c);
i += 2;
}
break;
}
default: {
write_char(c);
}
for(u32 i = 0; i < size;i++) {
if(fmt[i] == '\n') {
frame_buffer_newline();
}
else {
write_char(fmt[i]);
}
}
}

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@ -2,7 +2,11 @@
#include "framebuffer.h"
// Frame buffer driver
// NOTE: not getting computed at compile time so we always have a call
u32 strlen(char*);
u32 write(const char*, const u32);
u32 read(const u32);
void printf(char*);