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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 18:20:36 -0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/arm/nwfpe/fpa11.c
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'arch/arm/nwfpe/fpa11.c')
-rw-r--r--arch/arm/nwfpe/fpa11.c143
1 files changed, 143 insertions, 0 deletions
diff --git a/arch/arm/nwfpe/fpa11.c b/arch/arm/nwfpe/fpa11.c
new file mode 100644
index 000000000000..bf61696865ec
--- /dev/null
+++ b/arch/arm/nwfpe/fpa11.c
@@ -0,0 +1,143 @@
1/*
2 NetWinder Floating Point Emulator
3 (c) Rebel.COM, 1998,1999
4 (c) Philip Blundell, 2001
5
6 Direct questions, comments to Scott Bambrough <scottb@netwinder.org>
7
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
12
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with this program; if not, write to the Free Software
20 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21*/
22
23#include "fpa11.h"
24#include "fpopcode.h"
25
26#include "fpmodule.h"
27#include "fpmodule.inl"
28
29#include <linux/config.h>
30#include <linux/compiler.h>
31#include <linux/string.h>
32#include <asm/system.h>
33
34/* forward declarations */
35unsigned int EmulateCPDO(const unsigned int);
36unsigned int EmulateCPDT(const unsigned int);
37unsigned int EmulateCPRT(const unsigned int);
38
39/* Reset the FPA11 chip. Called to initialize and reset the emulator. */
40static void resetFPA11(void)
41{
42 int i;
43 FPA11 *fpa11 = GET_FPA11();
44
45 /* initialize the register type array */
46 for (i = 0; i <= 7; i++) {
47 fpa11->fType[i] = typeNone;
48 }
49
50 /* FPSR: set system id to FP_EMULATOR, set AC, clear all other bits */
51 fpa11->fpsr = FP_EMULATOR | BIT_AC;
52}
53
54void SetRoundingMode(const unsigned int opcode)
55{
56 switch (opcode & MASK_ROUNDING_MODE) {
57 default:
58 case ROUND_TO_NEAREST:
59 float_rounding_mode = float_round_nearest_even;
60 break;
61
62 case ROUND_TO_PLUS_INFINITY:
63 float_rounding_mode = float_round_up;
64 break;
65
66 case ROUND_TO_MINUS_INFINITY:
67 float_rounding_mode = float_round_down;
68 break;
69
70 case ROUND_TO_ZERO:
71 float_rounding_mode = float_round_to_zero;
72 break;
73 }
74}
75
76void SetRoundingPrecision(const unsigned int opcode)
77{
78#ifdef CONFIG_FPE_NWFPE_XP
79 switch (opcode & MASK_ROUNDING_PRECISION) {
80 case ROUND_SINGLE:
81 floatx80_rounding_precision = 32;
82 break;
83
84 case ROUND_DOUBLE:
85 floatx80_rounding_precision = 64;
86 break;
87
88 case ROUND_EXTENDED:
89 floatx80_rounding_precision = 80;
90 break;
91
92 default:
93 floatx80_rounding_precision = 80;
94 }
95#endif
96}
97
98void nwfpe_init_fpa(union fp_state *fp)
99{
100 FPA11 *fpa11 = (FPA11 *)fp;
101#ifdef NWFPE_DEBUG
102 printk("NWFPE: setting up state.\n");
103#endif
104 memset(fpa11, 0, sizeof(FPA11));
105 resetFPA11();
106 SetRoundingMode(ROUND_TO_NEAREST);
107 SetRoundingPrecision(ROUND_EXTENDED);
108 fpa11->initflag = 1;
109}
110
111/* Emulate the instruction in the opcode. */
112unsigned int EmulateAll(unsigned int opcode)
113{
114 unsigned int code;
115
116#ifdef NWFPE_DEBUG
117 printk("NWFPE: emulating opcode %08x\n", opcode);
118#endif
119 code = opcode & 0x00000f00;
120 if (code == 0x00000100 || code == 0x00000200) {
121 /* For coprocessor 1 or 2 (FPA11) */
122 code = opcode & 0x0e000000;
123 if (code == 0x0e000000) {
124 if (opcode & 0x00000010) {
125 /* Emulate conversion opcodes. */
126 /* Emulate register transfer opcodes. */
127 /* Emulate comparison opcodes. */
128 return EmulateCPRT(opcode);
129 } else {
130 /* Emulate monadic arithmetic opcodes. */
131 /* Emulate dyadic arithmetic opcodes. */
132 return EmulateCPDO(opcode);
133 }
134 } else if (code == 0x0c000000) {
135 /* Emulate load/store opcodes. */
136 /* Emulate load/store multiple opcodes. */
137 return EmulateCPDT(opcode);
138 }
139 }
140
141 /* Invalid instruction detected. Return FALSE. */
142 return 0;
143}