linux-stable/arch/parisc/math-emu/driver.c
Thomas Gleixner 660662f857 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 150
Based on 1 normalized pattern(s):

  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

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 42 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190524100845.259718220@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:25:19 -07:00

112 lines
3 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Linux/PA-RISC Project (http://www.parisc-linux.org/)
*
* Floating-point emulation code
* Copyright (C) 2001 Hewlett-Packard (Paul Bame) <bame@debian.org>
*/
/*
* 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/signal.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);
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) {
force_sig_fault(signalcode >> 24, signalcode & 0xffffff,
(void __user *) regs->iaoq[0], current);
return -1;
}
return signalcode ? -1 : 0;
}