Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
[cris-mirror.git] / arch / parisc / math-emu / driver.c
blob2fb59d2e2b294bb38484da2b72a49f64a816b4a2
1 /*
2 * Linux/PA-RISC Project (http://www.parisc-linux.org/)
4 * Floating-point emulation code
5 * Copyright (C) 2001 Hewlett-Packard (Paul Bame) <bame@debian.org>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License as published by
9 * the Free Software Foundation; either version 2, or (at your option)
10 * any later version.
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 * linux/arch/math-emu/driver.c.c
24 * decodes and dispatches unimplemented FPU instructions
26 * Copyright (C) 1999, 2000 Philipp Rumpf <prumpf@tux.org>
27 * Copyright (C) 2001 Hewlett-Packard <bame@debian.org>
30 #include <linux/sched/signal.h>
32 #include "float.h"
33 #include "math-emu.h"
36 #define fptpos 31
37 #define fpr1pos 10
38 #define extru(r,pos,len) (((r) >> (31-(pos))) & (( 1 << (len)) - 1))
40 #define FPUDEBUG 0
42 /* Format of the floating-point exception registers. */
43 struct exc_reg {
44 unsigned int exception : 6;
45 unsigned int ei : 26;
48 /* Macros for grabbing bits of the instruction format from the 'ei'
49 field above. */
50 /* Major opcode 0c and 0e */
51 #define FP0CE_UID(i) (((i) >> 6) & 3)
52 #define FP0CE_CLASS(i) (((i) >> 9) & 3)
53 #define FP0CE_SUBOP(i) (((i) >> 13) & 7)
54 #define FP0CE_SUBOP1(i) (((i) >> 15) & 7) /* Class 1 subopcode */
55 #define FP0C_FORMAT(i) (((i) >> 11) & 3)
56 #define FP0E_FORMAT(i) (((i) >> 11) & 1)
58 /* Major opcode 0c, uid 2 (performance monitoring) */
59 #define FPPM_SUBOP(i) (((i) >> 9) & 0x1f)
61 /* Major opcode 2e (fused operations). */
62 #define FP2E_SUBOP(i) (((i) >> 5) & 1)
63 #define FP2E_FORMAT(i) (((i) >> 11) & 1)
65 /* Major opcode 26 (FMPYSUB) */
66 /* Major opcode 06 (FMPYADD) */
67 #define FPx6_FORMAT(i) ((i) & 0x1f)
69 /* Flags and enable bits of the status word. */
70 #define FPSW_FLAGS(w) ((w) >> 27)
71 #define FPSW_ENABLE(w) ((w) & 0x1f)
72 #define FPSW_V (1<<4)
73 #define FPSW_Z (1<<3)
74 #define FPSW_O (1<<2)
75 #define FPSW_U (1<<1)
76 #define FPSW_I (1<<0)
78 /* Handle a floating point exception. Return zero if the faulting
79 instruction can be completed successfully. */
80 int
81 handle_fpe(struct pt_regs *regs)
83 extern void printbinary(unsigned long x, int nbits);
84 struct siginfo si;
85 unsigned int orig_sw, sw;
86 int signalcode;
87 /* need an intermediate copy of float regs because FPU emulation
88 * code expects an artificial last entry which contains zero
90 * also, the passed in fr registers contain one word that defines
91 * the fpu type. the fpu type information is constructed
92 * inside the emulation code
94 __u64 frcopy[36];
96 memcpy(frcopy, regs->fr, sizeof regs->fr);
97 frcopy[32] = 0;
99 memcpy(&orig_sw, frcopy, sizeof(orig_sw));
101 if (FPUDEBUG) {
102 printk(KERN_DEBUG "FP VZOUICxxxxCQCQCQCQCQCRMxxTDVZOUI ->\n ");
103 printbinary(orig_sw, 32);
104 printk(KERN_DEBUG "\n");
107 signalcode = decode_fpu(frcopy, 0x666);
109 /* Status word = FR0L. */
110 memcpy(&sw, frcopy, sizeof(sw));
111 if (FPUDEBUG) {
112 printk(KERN_DEBUG "VZOUICxxxxCQCQCQCQCQCRMxxTDVZOUI decode_fpu returns %d|0x%x\n",
113 signalcode >> 24, signalcode & 0xffffff);
114 printbinary(sw, 32);
115 printk(KERN_DEBUG "\n");
118 memcpy(regs->fr, frcopy, sizeof regs->fr);
119 if (signalcode != 0) {
120 si.si_signo = signalcode >> 24;
121 si.si_errno = 0;
122 si.si_code = signalcode & 0xffffff;
123 si.si_addr = (void __user *) regs->iaoq[0];
124 force_sig_info(si.si_signo, &si, current);
125 return -1;
128 return signalcode ? -1 : 0;