Add PS/2 attempt

This commit is contained in:
Kat R. 2022-10-29 10:06:37 -05:00
parent 02c887dcea
commit 5b4e9dccd6
1 changed files with 75 additions and 1 deletions

View File

@ -3,6 +3,7 @@
#include <string.h>
#include <sys/io.h>
#include "gdt.h"
#include "ps2_kbd.h"
int tss[16][2];
@ -42,11 +43,84 @@ void setup_gdt(void) {
extern void enter_pmode(void);
int initialize_ps2_kbd() {
/* Should really make sure PS/2 controller exists here: */
/* Disable devices */
outb(0xAD, 0x64);
outb(0xA7, 0xAD);
/* Flush output buffer */
get_ps2_inbyte();
/* Set config byte */
outb(0x20, 0x64);
unsigned char config_byte = get_ps2_inbyte();
int is_dual_ch = (config_byte & 020) != 0 ? 1 : 0;
config_byte &= 0274;
outb(0x60, 0x64);
outb(config_byte, 0x60);
/* Quick self-test */
outb(0xAA, 0x64);
unsigned char test_response = get_ps2_inbyte();
if(test_response != 0x55) {
printf("error: PS/2 self-test failed\n");
return 1;
}
outb(0x60, 0x64);
outb(config_byte, 0x60);
/* Double check dual channel stuff */
if(is_dual_ch) {
outb(0xA8, 0x64);
outb(0x20, 0x64);
unsigned char new_config_byte = get_ps2_inbyte();
is_dual_ch = (new_config_byte & 020) == 0 ? 1 : 0;
if(is_dual_ch) {
outb(0xA7, 0x64);
}
}
/* Interface tests */
outb(0xAB, 0x64);
test_response = get_ps2_inbyte();
int working_ports = test_response == 0x00 ? 01 : 00;
if(test_response != 0x00 && !is_dual_ch) {
printf("error: could not initialize PS/2 device\n");
return 2;
}
if(is_dual_ch) {
outb(0xA9, 0x64);
test_response = get_ps2_inbyte();
working_ports |= test_response == 0x00 ? 02 : 00;
if(test_response != 0x00 && working_ports != 01) {
printf("error: could not initialize PS/2 device\n");
return 2;
}
}
/* Enable devices */
if(working_ports & 01) {
outb(0xAE, 0x64);
config_byte |= 01;
}
if(working_ports & 02) {
outb(0xA8, 0x64);
config_byte |= 02;
}
outb(0x60, 0x64);
outb(config_byte, 0x60);
return 0;
}
int init(void) {
printf("Setting up GDT...\n");
setup_gdt();
printf("Enabling interrupts...\n");
idt_init();
printf("Fenix Dev Pre-release v0.0.3\n");
printf("Initializing PS/2 controller...\n");
initialize_ps2_kbd();
return 0;
}