xref: /openbmc/linux/arch/powerpc/math-emu/lfs.c (revision 2a598d0b)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/types.h>
3 #include <linux/errno.h>
4 #include <linux/uaccess.h>
5 
6 #include <asm/sfp-machine.h>
7 #include <math-emu/soft-fp.h>
8 #include <math-emu/double.h>
9 #include <math-emu/single.h>
10 
11 int
12 lfs(void *frD, void *ea)
13 {
14 	FP_DECL_D(R);
15 	FP_DECL_S(A);
16 	FP_DECL_EX;
17 	float f;
18 
19 #ifdef DEBUG
20 	printk("%s: D %p, ea %p\n", __func__, frD, ea);
21 #endif
22 
23 	if (copy_from_user(&f, ea, sizeof(float)))
24 		return -EFAULT;
25 
26 	FP_UNPACK_S(A, f);
27 
28 #ifdef DEBUG
29 	printk("A: %ld %lu %ld (%ld) [%08lx]\n", A_s, A_f, A_e, A_c,
30 	       *(unsigned long *)&f);
31 #endif
32 
33 	FP_CONV(D, S, 2, 1, R, A);
34 
35 #ifdef DEBUG
36 	printk("R: %ld %lu %lu %ld (%ld)\n", R_s, R_f1, R_f0, R_e, R_c);
37 #endif
38 
39 	if (R_c == FP_CLS_NAN) {
40 		R_e = _FP_EXPMAX_D;
41 		_FP_PACK_RAW_2_P(D, frD, R);
42 	} else {
43 		__FP_PACK_D(frD, R);
44 	}
45 
46 	return 0;
47 }
48