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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-17 02:20:36 +0400
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-17 02:20:36 +0400
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/arm/nwfpe/fpa11.c
downloadlinux-1da177e4c3f41524e886b7f1b8a0c1fc7321cac2.tar.xz
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
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+++ b/arch/arm/nwfpe/fpa11.c
@@ -0,0 +1,143 @@
+/*
+ NetWinder Floating Point Emulator
+ (c) Rebel.COM, 1998,1999
+ (c) Philip Blundell, 2001
+
+ Direct questions, comments to Scott Bambrough <scottb@netwinder.org>
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#include "fpa11.h"
+#include "fpopcode.h"
+
+#include "fpmodule.h"
+#include "fpmodule.inl"
+
+#include <linux/config.h>
+#include <linux/compiler.h>
+#include <linux/string.h>
+#include <asm/system.h>
+
+/* forward declarations */
+unsigned int EmulateCPDO(const unsigned int);
+unsigned int EmulateCPDT(const unsigned int);
+unsigned int EmulateCPRT(const unsigned int);
+
+/* Reset the FPA11 chip. Called to initialize and reset the emulator. */
+static void resetFPA11(void)
+{
+ int i;
+ FPA11 *fpa11 = GET_FPA11();
+
+ /* initialize the register type array */
+ for (i = 0; i <= 7; i++) {
+ fpa11->fType[i] = typeNone;
+ }
+
+ /* FPSR: set system id to FP_EMULATOR, set AC, clear all other bits */
+ fpa11->fpsr = FP_EMULATOR | BIT_AC;
+}
+
+void SetRoundingMode(const unsigned int opcode)
+{
+ switch (opcode & MASK_ROUNDING_MODE) {
+ default:
+ case ROUND_TO_NEAREST:
+ float_rounding_mode = float_round_nearest_even;
+ break;
+
+ case ROUND_TO_PLUS_INFINITY:
+ float_rounding_mode = float_round_up;
+ break;
+
+ case ROUND_TO_MINUS_INFINITY:
+ float_rounding_mode = float_round_down;
+ break;
+
+ case ROUND_TO_ZERO:
+ float_rounding_mode = float_round_to_zero;
+ break;
+ }
+}
+
+void SetRoundingPrecision(const unsigned int opcode)
+{
+#ifdef CONFIG_FPE_NWFPE_XP
+ switch (opcode & MASK_ROUNDING_PRECISION) {
+ case ROUND_SINGLE:
+ floatx80_rounding_precision = 32;
+ break;
+
+ case ROUND_DOUBLE:
+ floatx80_rounding_precision = 64;
+ break;
+
+ case ROUND_EXTENDED:
+ floatx80_rounding_precision = 80;
+ break;
+
+ default:
+ floatx80_rounding_precision = 80;
+ }
+#endif
+}
+
+void nwfpe_init_fpa(union fp_state *fp)
+{
+ FPA11 *fpa11 = (FPA11 *)fp;
+#ifdef NWFPE_DEBUG
+ printk("NWFPE: setting up state.\n");
+#endif
+ memset(fpa11, 0, sizeof(FPA11));
+ resetFPA11();
+ SetRoundingMode(ROUND_TO_NEAREST);
+ SetRoundingPrecision(ROUND_EXTENDED);
+ fpa11->initflag = 1;
+}
+
+/* Emulate the instruction in the opcode. */
+unsigned int EmulateAll(unsigned int opcode)
+{
+ unsigned int code;
+
+#ifdef NWFPE_DEBUG
+ printk("NWFPE: emulating opcode %08x\n", opcode);
+#endif
+ code = opcode & 0x00000f00;
+ if (code == 0x00000100 || code == 0x00000200) {
+ /* For coprocessor 1 or 2 (FPA11) */
+ code = opcode & 0x0e000000;
+ if (code == 0x0e000000) {
+ if (opcode & 0x00000010) {
+ /* Emulate conversion opcodes. */
+ /* Emulate register transfer opcodes. */
+ /* Emulate comparison opcodes. */
+ return EmulateCPRT(opcode);
+ } else {
+ /* Emulate monadic arithmetic opcodes. */
+ /* Emulate dyadic arithmetic opcodes. */
+ return EmulateCPDO(opcode);
+ }
+ } else if (code == 0x0c000000) {
+ /* Emulate load/store opcodes. */
+ /* Emulate load/store multiple opcodes. */
+ return EmulateCPDT(opcode);
+ }
+ }
+
+ /* Invalid instruction detected. Return FALSE. */
+ return 0;
+}