amdcpuid: A small tool for OS.h

* Takes an AMD CPUID and converts it to a number for OS.h
* Splits on family 0xF as per AMD recommendation

src/tools/amdcpuid.c

@@ -0,0 +1,94 @@
+/*
+ * Copyright 2012 Haiku, Inc. All rights reserved.
+ * Distributed under the terms of the MIT License.
+ *
+ * Authors:
+ *		Alexander von Gluck, kallisti5@unixzen.com
+ */
+
+/*
+ * Pass an AMD CPUID in hex, and get out a CPUID for OS.h
+ */
+
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+
+#define AMDCPU 0x1100
+
+#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, xv, fact;
+
+	if (szlen > 0) {
+		// Converting more than 32bit hexadecimal value?
+		if (szlen>8) return 2; // exit
+
+		// 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 != 2) {
+		printf("Provide the AMD cpuid in hex, and you will get how we id it\n");
+		printf("usage: amdcpuid <cpuid_hex>\n");
+		return 1;
+	}
+
+	unsigned int cpuid;
+	xtoi(argv[1], &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;
+
+	if (family == 0xF)
+		printf("model: 0x%lX\n", extFam + (extMod << 4) + model + 0x1100);
+	else
+		printf("model: 0x%lX\n", (family << 4) + model + 0x1100);
+
+	return 0;
+}