fernlader2/src/Qcommon.c

//#include <stdint.h>

typedef unsigned char uint8_t;
typedef unsigned short uint16_t;
typedef unsigned int uint32_t;

#define COM1_BASE_PORT 0x3F8

static inline uint8_t
inb(uint16_t port)
{
	uint8_t data;
	__asm__ ("inb %%dx, %%al" : "=a"(data) : "d"(port));
	return data;
}

static inline void
outb(uint16_t port, uint8_t data)
{
	__asm__ ("outb %%al, %%dx" :: "a"(data), "d"(port));
}

void serial_write_char(char c)
{
	while (1) {
		int line_status = inb(COM1_BASE_PORT + 5);
		if (line_status & 0x20) {
			break;
		}
	}
	outb(COM1_BASE_PORT, c);
}

void serial_write(const char *msg)
{
	for (const char *c = msg; *c; c++) {
		outb(0xE9, *c);
		//serial_write_char(*c);
	}
}

extern void bios_write(const char *msg, unsigned length);
extern void *bios_getmap(void *buffer);

unsigned char memmap[24 * 128];

void
main()
{
	bios_write("init\r\n", 6);
	void *end = bios_getmap(memmap);
	bios_write("karlos\r\n", 8);
	for (int i = 0; ; i++) {
		unsigned char *entry = memmap + 24 * i;
		if (entry >= end) break;
		unsigned char type = *(entry + 16);
		char c = type < 10 ? type + '0' : '?';
		bios_write(&c, 1);
	}
	for (;;) {
		__asm__ ("hlt" :);
	}
}