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Diffstat (limited to 'arch/parisc/math-emu/driver.c')
| -rw-r--r-- | arch/parisc/math-emu/driver.c | 128 |
1 files changed, 128 insertions, 0 deletions
diff --git a/arch/parisc/math-emu/driver.c b/arch/parisc/math-emu/driver.c new file mode 100644 index 000000000..09ef4136c --- /dev/null +++ b/arch/parisc/math-emu/driver.c @@ -0,0 +1,128 @@ +/* + * Linux/PA-RISC Project (http://www.parisc-linux.org/) + * + * Floating-point emulation code + * Copyright (C) 2001 Hewlett-Packard (Paul Bame) <bame@debian.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, 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ +/* + * linux/arch/math-emu/driver.c.c + * + * decodes and dispatches unimplemented FPU instructions + * + * Copyright (C) 1999, 2000 Philipp Rumpf <prumpf@tux.org> + * Copyright (C) 2001 Hewlett-Packard <bame@debian.org> + */ + +#include <linux/sched.h> +#include "float.h" +#include "math-emu.h" + + +#define fptpos 31 +#define fpr1pos 10 +#define extru(r,pos,len) (((r) >> (31-(pos))) & (( 1 << (len)) - 1)) + +#define FPUDEBUG 0 + +/* Format of the floating-point exception registers. */ +struct exc_reg { + unsigned int exception : 6; + unsigned int ei : 26; +}; + +/* Macros for grabbing bits of the instruction format from the 'ei' + field above. */ +/* Major opcode 0c and 0e */ +#define FP0CE_UID(i) (((i) >> 6) & 3) +#define FP0CE_CLASS(i) (((i) >> 9) & 3) +#define FP0CE_SUBOP(i) (((i) >> 13) & 7) +#define FP0CE_SUBOP1(i) (((i) >> 15) & 7) /* Class 1 subopcode */ +#define FP0C_FORMAT(i) (((i) >> 11) & 3) +#define FP0E_FORMAT(i) (((i) >> 11) & 1) + +/* Major opcode 0c, uid 2 (performance monitoring) */ +#define FPPM_SUBOP(i) (((i) >> 9) & 0x1f) + +/* Major opcode 2e (fused operations). */ +#define FP2E_SUBOP(i) (((i) >> 5) & 1) +#define FP2E_FORMAT(i) (((i) >> 11) & 1) + +/* Major opcode 26 (FMPYSUB) */ +/* Major opcode 06 (FMPYADD) */ +#define FPx6_FORMAT(i) ((i) & 0x1f) + +/* Flags and enable bits of the status word. */ +#define FPSW_FLAGS(w) ((w) >> 27) +#define FPSW_ENABLE(w) ((w) & 0x1f) +#define FPSW_V (1<<4) +#define FPSW_Z (1<<3) +#define FPSW_O (1<<2) +#define FPSW_U (1<<1) +#define FPSW_I (1<<0) + +/* Handle a floating point exception. Return zero if the faulting + instruction can be completed successfully. */ +int +handle_fpe(struct pt_regs *regs) +{ + extern void printbinary(unsigned long x, int nbits); + struct siginfo si; + unsigned int orig_sw, sw; + int signalcode; + /* need an intermediate copy of float regs because FPU emulation + * code expects an artificial last entry which contains zero + * + * also, the passed in fr registers contain one word that defines + * the fpu type. the fpu type information is constructed + * inside the emulation code + */ + __u64 frcopy[36]; + + memcpy(frcopy, regs->fr, sizeof regs->fr); + frcopy[32] = 0; + + memcpy(&orig_sw, frcopy, sizeof(orig_sw)); + + if (FPUDEBUG) { + printk(KERN_DEBUG "FP VZOUICxxxxCQCQCQCQCQCRMxxTDVZOUI ->\n "); + printbinary(orig_sw, 32); + printk(KERN_DEBUG "\n"); + } + + signalcode = decode_fpu(frcopy, 0x666); + + /* Status word = FR0L. */ + memcpy(&sw, frcopy, sizeof(sw)); + if (FPUDEBUG) { + printk(KERN_DEBUG "VZOUICxxxxCQCQCQCQCQCRMxxTDVZOUI decode_fpu returns %d|0x%x\n", + signalcode >> 24, signalcode & 0xffffff); + printbinary(sw, 32); + printk(KERN_DEBUG "\n"); + } + + memcpy(regs->fr, frcopy, sizeof regs->fr); + if (signalcode != 0) { + si.si_signo = signalcode >> 24; + si.si_errno = 0; + si.si_code = signalcode & 0xffffff; + si.si_addr = (void __user *) regs->iaoq[0]; + force_sig_info(si.si_signo, &si, current); + return -1; + } + + return signalcode ? -1 : 0; +} |