1 /*
2 * Kevin D. Kissell, kevink@mips and Carsten Langgaard, carstenl@mips.com
3 * Copyright (C) 2000 MIPS Technologies, Inc. All rights reserved.
4 *
5 * This program is free software; you can distribute it and/or modify it
6 * under the terms of the GNU General Public License (Version 2) as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * for more details.
13 *
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 59 Temple Place - Suite 330, Boston MA 02111-1307, USA.
17 *
18 * Routines corresponding to Linux kernel FP context
19 * manipulation primitives for the Algorithmics MIPS
20 * FPU Emulator
21 */
22 #include <linux/sched.h>
23 #include <asm/processor.h>
24 #include <asm/signal.h>
25 #include <asm/uaccess.h>
26
27 #include <asm/fpu.h>
28 #include <asm/fpu_emulator.h>
29
30 #define SIGNALLING_NAN 0x7ff800007ff80000LL
31
fpu_emulator_init_fpu(void)32 void fpu_emulator_init_fpu(void)
33 {
34 static int first = 1;
35 int i;
36
37 if (first) {
38 first = 0;
39 printk("Algorithmics/MIPS FPU Emulator v1.5\n");
40 }
41
42 current->thread.fpu.fcr31 = 0;
43 for (i = 0; i < 32; i++) {
44 current->thread.fpu.fpr[i] = SIGNALLING_NAN;
45 }
46 }
47
48
49 /*
50 * Emulator context save/restore to/from a signal context
51 * presumed to be on the user stack, and therefore accessed
52 * with appropriate macros from uaccess.h
53 */
54
fpu_emulator_save_context(struct sigcontext __user * sc)55 int fpu_emulator_save_context(struct sigcontext __user *sc)
56 {
57 int i;
58 int err = 0;
59
60 for (i = 0; i < 32; i++) {
61 err |=
62 __put_user(current->thread.fpu.fpr[i], &sc->sc_fpregs[i]);
63 }
64 err |= __put_user(current->thread.fpu.fcr31, &sc->sc_fpc_csr);
65
66 return err;
67 }
68
fpu_emulator_restore_context(struct sigcontext __user * sc)69 int fpu_emulator_restore_context(struct sigcontext __user *sc)
70 {
71 int i;
72 int err = 0;
73
74 for (i = 0; i < 32; i++) {
75 err |=
76 __get_user(current->thread.fpu.fpr[i], &sc->sc_fpregs[i]);
77 }
78 err |= __get_user(current->thread.fpu.fcr31, &sc->sc_fpc_csr);
79
80 return err;
81 }
82
83 #ifdef CONFIG_64BIT
84 /*
85 * This is the o32 version
86 */
87
fpu_emulator_save_context32(struct sigcontext32 __user * sc)88 int fpu_emulator_save_context32(struct sigcontext32 __user *sc)
89 {
90 int i;
91 int err = 0;
92
93 for (i = 0; i < 32; i+=2) {
94 err |=
95 __put_user(current->thread.fpu.fpr[i], &sc->sc_fpregs[i]);
96 }
97 err |= __put_user(current->thread.fpu.fcr31, &sc->sc_fpc_csr);
98
99 return err;
100 }
101
fpu_emulator_restore_context32(struct sigcontext32 __user * sc)102 int fpu_emulator_restore_context32(struct sigcontext32 __user *sc)
103 {
104 int i;
105 int err = 0;
106
107 for (i = 0; i < 32; i+=2) {
108 err |=
109 __get_user(current->thread.fpu.fpr[i], &sc->sc_fpregs[i]);
110 }
111 err |= __get_user(current->thread.fpu.fcr31, &sc->sc_fpc_csr);
112
113 return err;
114 }
115 #endif
116