/*
 * Copyright 2012 Haiku, Inc. All rights reserved.
 * Distributed under the terms of the MIT License.
 *
 * Authors:
 *		Alexander von Gluck, kallisti5@unixzen.com
 */

/*
 * Pass a standard CPUID in hex, and get out a CPUID for OS.h
 */


#include <stdio.h>
#include <stdlib.h>
#include <string.h>


#define EXT_FAMILY_MASK 0xF00000
#define EXT_MODEL_MASK	0x0F0000
#define FAMILY_MASK		0x000F00
#define MODEL_MASK		0x0000F0
#define STEPPING_MASK	0x00000F


// Converts a hexadecimal string to integer
static int
xtoi(const char* xs, unsigned int* result)
{
	size_t szlen = strlen(xs);
	int i;
	int xv;
	int fact;

	if (szlen > 0) {
		// Converting more than 32bit hexadecimal value?
		if (szlen > 8)
			return 2;

		// Begin conversion here
		*result = 0;
		fact = 1;

		// Run until no more character to convert
		for (i = szlen - 1; i>=0; i--) {
			if (isxdigit(*(xs + i))) {
				if (*(xs + i) >= 97)
					xv = (*(xs + i) - 97) + 10;
				else if (*(xs + i) >= 65)
					xv = (*(xs + i) - 65) + 10;
				else
					xv = *(xs + i) - 48;

				*result += (xv * fact);
				fact *= 16;
			} else {
				// Conversion was abnormally terminated
				// by non hexadecimal digit, hence
				// returning only the converted with
				// an error value 4 (illegal hex character)
				return 4;
			}
		}
	}

	// Nothing to convert
	return 1;
}


int
main(int argc, char *argv[])
{
	if (argc != 3) {
		printf("Provide the cpuid in hex, and you will get how we id it\n");
		printf("usage: cpuidhaiku <AMD|INTEL> <cpuid_hex>\n");
		return 1;
	}

	unsigned int cpuid = 0;
	xtoi(argv[2], &cpuid);

	printf("cpuid: 0x%X\n", cpuid);

	unsigned int extFam = (cpuid & EXT_FAMILY_MASK) >> 20;
	unsigned int extMod = (cpuid & EXT_MODEL_MASK) >> 16;
	unsigned int family = (cpuid & FAMILY_MASK) >> 8;
	unsigned int model = (cpuid & MODEL_MASK) >> 4;
	unsigned int stepping = (cpuid & STEPPING_MASK);

	unsigned int cpuidHaiku;
	if (strncmp(argv[1], "AMD", 3) == 0) {
		if (family == 0xF) {
			cpuidHaiku = (extFam << 20) + (extMod << 16)
				+ (family << 4) + model;
		} else
			cpuidHaiku = (family << 4) + model;
		cpuidHaiku += 0x1100; // AMD vendor id
	} else if (strncmp(argv[1], "INTEL", 5) == 0) {
		cpuidHaiku = (extFam << 20) + (extMod << 16)
			+ (family << 4) + model;
		cpuidHaiku += 0x1000; // Intel vendor id
	} else {
		printf("Vendor should be AMD or INTEL\n");
		return 1;
	}

	printf("Haiku CPUID: 0x%lx\n", cpuidHaiku);

	return 0;
}