blob: 8ad4ed6a6c9b437b9d6658803e7b865099ea9cb5 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * arch/sh64/kernel/fpu.c
7 *
8 * Copyright (C) 2001 Manuela Cirronis, Paolo Alberelli
9 * Copyright (C) 2002 STMicroelectronics Limited
10 * Author : Stuart Menefy
11 *
12 * Started from SH4 version:
13 * Copyright (C) 1999, 2000 Kaz Kojima & Niibe Yutaka
14 *
15 */
16
17#include <linux/sched.h>
18#include <linux/signal.h>
19#include <asm/processor.h>
20#include <asm/user.h>
21#include <asm/io.h>
22
23/*
24 * Initially load the FPU with signalling NANS. This bit pattern
25 * has the property that no matter whether considered as single or as
26 * double precision, it still represents a signalling NAN.
27 */
28#define sNAN64 0xFFFFFFFFFFFFFFFFULL
29#define sNAN32 0xFFFFFFFFUL
30
31static union sh_fpu_union init_fpuregs = {
32 .hard = {
33 .fp_regs = { [0 ... 63] = sNAN32 },
34 .fpscr = FPSCR_INIT
35 }
36};
37
38inline void fpsave(struct sh_fpu_hard_struct *fpregs)
39{
40 asm volatile("fst.p %0, (0*8), fp0\n\t"
41 "fst.p %0, (1*8), fp2\n\t"
42 "fst.p %0, (2*8), fp4\n\t"
43 "fst.p %0, (3*8), fp6\n\t"
44 "fst.p %0, (4*8), fp8\n\t"
45 "fst.p %0, (5*8), fp10\n\t"
46 "fst.p %0, (6*8), fp12\n\t"
47 "fst.p %0, (7*8), fp14\n\t"
48 "fst.p %0, (8*8), fp16\n\t"
49 "fst.p %0, (9*8), fp18\n\t"
50 "fst.p %0, (10*8), fp20\n\t"
51 "fst.p %0, (11*8), fp22\n\t"
52 "fst.p %0, (12*8), fp24\n\t"
53 "fst.p %0, (13*8), fp26\n\t"
54 "fst.p %0, (14*8), fp28\n\t"
55 "fst.p %0, (15*8), fp30\n\t"
56 "fst.p %0, (16*8), fp32\n\t"
57 "fst.p %0, (17*8), fp34\n\t"
58 "fst.p %0, (18*8), fp36\n\t"
59 "fst.p %0, (19*8), fp38\n\t"
60 "fst.p %0, (20*8), fp40\n\t"
61 "fst.p %0, (21*8), fp42\n\t"
62 "fst.p %0, (22*8), fp44\n\t"
63 "fst.p %0, (23*8), fp46\n\t"
64 "fst.p %0, (24*8), fp48\n\t"
65 "fst.p %0, (25*8), fp50\n\t"
66 "fst.p %0, (26*8), fp52\n\t"
67 "fst.p %0, (27*8), fp54\n\t"
68 "fst.p %0, (28*8), fp56\n\t"
69 "fst.p %0, (29*8), fp58\n\t"
70 "fst.p %0, (30*8), fp60\n\t"
71 "fst.p %0, (31*8), fp62\n\t"
72
73 "fgetscr fr63\n\t"
74 "fst.s %0, (32*8), fr63\n\t"
75 : /* no output */
76 : "r" (fpregs)
77 : "memory");
78}
79
80
81static inline void
82fpload(struct sh_fpu_hard_struct *fpregs)
83{
84 asm volatile("fld.p %0, (0*8), fp0\n\t"
85 "fld.p %0, (1*8), fp2\n\t"
86 "fld.p %0, (2*8), fp4\n\t"
87 "fld.p %0, (3*8), fp6\n\t"
88 "fld.p %0, (4*8), fp8\n\t"
89 "fld.p %0, (5*8), fp10\n\t"
90 "fld.p %0, (6*8), fp12\n\t"
91 "fld.p %0, (7*8), fp14\n\t"
92 "fld.p %0, (8*8), fp16\n\t"
93 "fld.p %0, (9*8), fp18\n\t"
94 "fld.p %0, (10*8), fp20\n\t"
95 "fld.p %0, (11*8), fp22\n\t"
96 "fld.p %0, (12*8), fp24\n\t"
97 "fld.p %0, (13*8), fp26\n\t"
98 "fld.p %0, (14*8), fp28\n\t"
99 "fld.p %0, (15*8), fp30\n\t"
100 "fld.p %0, (16*8), fp32\n\t"
101 "fld.p %0, (17*8), fp34\n\t"
102 "fld.p %0, (18*8), fp36\n\t"
103 "fld.p %0, (19*8), fp38\n\t"
104 "fld.p %0, (20*8), fp40\n\t"
105 "fld.p %0, (21*8), fp42\n\t"
106 "fld.p %0, (22*8), fp44\n\t"
107 "fld.p %0, (23*8), fp46\n\t"
108 "fld.p %0, (24*8), fp48\n\t"
109 "fld.p %0, (25*8), fp50\n\t"
110 "fld.p %0, (26*8), fp52\n\t"
111 "fld.p %0, (27*8), fp54\n\t"
112 "fld.p %0, (28*8), fp56\n\t"
113 "fld.p %0, (29*8), fp58\n\t"
114 "fld.p %0, (30*8), fp60\n\t"
115
116 "fld.s %0, (32*8), fr63\n\t"
117 "fputscr fr63\n\t"
118
119 "fld.p %0, (31*8), fp62\n\t"
120 : /* no output */
121 : "r" (fpregs) );
122}
123
124void fpinit(struct sh_fpu_hard_struct *fpregs)
125{
126 *fpregs = init_fpuregs.hard;
127}
128
129asmlinkage void
130do_fpu_error(unsigned long ex, struct pt_regs *regs)
131{
132 struct task_struct *tsk = current;
133
134 regs->pc += 4;
135
136 tsk->thread.trap_no = 11;
137 tsk->thread.error_code = 0;
138 force_sig(SIGFPE, tsk);
139}
140
141
142asmlinkage void
143do_fpu_state_restore(unsigned long ex, struct pt_regs *regs)
144{
145 void die(const char *str, struct pt_regs *regs, long err);
146
147 if (! user_mode(regs))
148 die("FPU used in kernel", regs, ex);
149
150 regs->sr &= ~SR_FD;
151
152 if (last_task_used_math == current)
153 return;
154
155 grab_fpu();
156 if (last_task_used_math != NULL) {
157 /* Other processes fpu state, save away */
158 fpsave(&last_task_used_math->thread.fpu.hard);
159 }
160 last_task_used_math = current;
161 if (used_math()) {
162 fpload(&current->thread.fpu.hard);
163 } else {
164 /* First time FPU user. */
165 fpload(&init_fpuregs.hard);
166 set_used_math();
167 }
168 release_fpu();
169}
170