1// SPDX-License-Identifier: GPL-2.0-only
 2/*
 3 * IEEE754 floating point arithmetic
 4 * double precision: CLASS.f
 5 * FPR[fd] = class(FPR[fs])
 6 *
 7 * MIPS floating point support
 8 * Copyright (C) 2015 Imagination Technologies, Ltd.
 9 * Author: Markos Chandras <markos.chandras@imgtec.com>
10 */
11
12#include "ieee754dp.h"
13
14int ieee754dp_2008class(union ieee754dp x)
15{
16	COMPXDP;
17
18	EXPLODEXDP;
19
20	/*
21	 * 10 bit mask as follows:
22	 *
23	 * bit0 = SNAN
24	 * bit1 = QNAN
25	 * bit2 = -INF
26	 * bit3 = -NORM
27	 * bit4 = -DNORM
28	 * bit5 = -ZERO
29	 * bit6 = INF
30	 * bit7 = NORM
31	 * bit8 = DNORM
32	 * bit9 = ZERO
33	 */
34
35	switch(xc) {
36	case IEEE754_CLASS_SNAN:
37		return 0x01;
38	case IEEE754_CLASS_QNAN:
39		return 0x02;
40	case IEEE754_CLASS_INF:
41		return 0x04 << (xs ? 0 : 4);
42	case IEEE754_CLASS_NORM:
43		return 0x08 << (xs ? 0 : 4);
44	case IEEE754_CLASS_DNORM:
45		return 0x10 << (xs ? 0 : 4);
46	case IEEE754_CLASS_ZERO:
47		return 0x20 << (xs ? 0 : 4);
48	default:
49		pr_err("Unknown class: %d\n", xc);
50		return 0;
51	}
52}