mtfsf.c

 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
 9int
10mtfsf(unsigned int FM, u32 *frB)
11{
12	u32 mask;
13	u32 fpscr;
14
15	if (likely(FM == 1))
16		mask = 0x0f;
17	else if (likely(FM == 0xff))
18		mask = ~0;
19	else {
20		mask = ((FM & 1) |
21				((FM << 3) & 0x10) |
22				((FM << 6) & 0x100) |
23				((FM << 9) & 0x1000) |
24				((FM << 12) & 0x10000) |
25				((FM << 15) & 0x100000) |
26				((FM << 18) & 0x1000000) |
27				((FM << 21) & 0x10000000)) * 15;
28	}
29
30	fpscr = ((__FPU_FPSCR & ~mask) | (frB[1] & mask)) &
31		~(FPSCR_VX | FPSCR_FEX | 0x800);
32
33	if (fpscr & (FPSCR_VXSNAN | FPSCR_VXISI | FPSCR_VXIDI |
34		     FPSCR_VXZDZ | FPSCR_VXIMZ | FPSCR_VXVC |
35		     FPSCR_VXSOFT | FPSCR_VXSQRT | FPSCR_VXCVI))
36		fpscr |= FPSCR_VX;
37
38	/* The bit order of exception enables and exception status
39	 * is the same. Simply shift and mask to check for enabled
40	 * exceptions.
41	 */
42	if (fpscr & (fpscr >> 22) &  0xf8)
43		fpscr |= FPSCR_FEX;
44
45	__FPU_FPSCR = fpscr;
46
47#ifdef DEBUG
48	printk("%s: %02x %p: %08lx\n", __func__, FM, frB, __FPU_FPSCR);
49#endif
50
51	return 0;
52}