diff options
Diffstat (limited to 'arch/sh/kernel/cpu/sh4/fpu.c')
| -rw-r--r-- | arch/sh/kernel/cpu/sh4/fpu.c | 514 |
1 files changed, 334 insertions, 180 deletions
diff --git a/arch/sh/kernel/cpu/sh4/fpu.c b/arch/sh/kernel/cpu/sh4/fpu.c index e624180..817f993 100644 --- a/arch/sh/kernel/cpu/sh4/fpu.c +++ b/arch/sh/kernel/cpu/sh4/fpu.c @@ -1,7 +1,4 @@ -/* $Id: fpu.c,v 1.4 2004/01/13 05:52:11 kkojima Exp $ - * - * linux/arch/sh/kernel/fpu.c - * +/* * Save/restore floating point context for signal handlers. * * This file is subject to the terms and conditions of the GNU General Public @@ -9,15 +6,16 @@ * for more details. * * Copyright (C) 1999, 2000 Kaz Kojima & Niibe Yutaka + * Copyright (C) 2006 ST Microelectronics Ltd. (denorm support) * - * FIXME! These routines can be optimized in big endian case. + * FIXME! These routines have not been tested for big endian case. */ - #include <linux/sched.h> #include <linux/signal.h> +#include <linux/io.h> +#include <asm/cpu/fpu.h> #include <asm/processor.h> #include <asm/system.h> -#include <asm/io.h> /* The PR (precision) bit in the FP Status Register must be clear when * an frchg instruction is executed, otherwise the instruction is undefined. @@ -25,113 +23,122 @@ */ #define FPSCR_RCHG 0x00000000 +extern unsigned long long float64_div(unsigned long long a, + unsigned long long b); +extern unsigned long int float32_div(unsigned long int a, unsigned long int b); +extern unsigned long long float64_mul(unsigned long long a, + unsigned long long b); +extern unsigned long int float32_mul(unsigned long int a, unsigned long int b); +extern unsigned long long float64_add(unsigned long long a, + unsigned long long b); +extern unsigned long int float32_add(unsigned long int a, unsigned long int b); +extern unsigned long long float64_sub(unsigned long long a, + unsigned long long b); +extern unsigned long int float32_sub(unsigned long int a, unsigned long int b); +static unsigned int fpu_exception_flags; /* * Save FPU registers onto task structure. * Assume called with FPU enabled (SR.FD=0). */ -void -save_fpu(struct task_struct *tsk, struct pt_regs *regs) +void save_fpu(struct task_struct *tsk, struct pt_regs *regs) { unsigned long dummy; clear_tsk_thread_flag(tsk, TIF_USEDFPU); enable_fpu(); - asm volatile("sts.l fpul, @-%0\n\t" - "sts.l fpscr, @-%0\n\t" - "lds %2, fpscr\n\t" - "frchg\n\t" - "fmov.s fr15, @-%0\n\t" - "fmov.s fr14, @-%0\n\t" - "fmov.s fr13, @-%0\n\t" - "fmov.s fr12, @-%0\n\t" - "fmov.s fr11, @-%0\n\t" - "fmov.s fr10, @-%0\n\t" - "fmov.s fr9, @-%0\n\t" - "fmov.s fr8, @-%0\n\t" - "fmov.s fr7, @-%0\n\t" - "fmov.s fr6, @-%0\n\t" - "fmov.s fr5, @-%0\n\t" - "fmov.s fr4, @-%0\n\t" - "fmov.s fr3, @-%0\n\t" - "fmov.s fr2, @-%0\n\t" - "fmov.s fr1, @-%0\n\t" - "fmov.s fr0, @-%0\n\t" - "frchg\n\t" - "fmov.s fr15, @-%0\n\t" - "fmov.s fr14, @-%0\n\t" - "fmov.s fr13, @-%0\n\t" - "fmov.s fr12, @-%0\n\t" - "fmov.s fr11, @-%0\n\t" - "fmov.s fr10, @-%0\n\t" - "fmov.s fr9, @-%0\n\t" - "fmov.s fr8, @-%0\n\t" - "fmov.s fr7, @-%0\n\t" - "fmov.s fr6, @-%0\n\t" - "fmov.s fr5, @-%0\n\t" - "fmov.s fr4, @-%0\n\t" - "fmov.s fr3, @-%0\n\t" - "fmov.s fr2, @-%0\n\t" - "fmov.s fr1, @-%0\n\t" - "fmov.s fr0, @-%0\n\t" - "lds %3, fpscr\n\t" - : "=r" (dummy) - : "0" ((char *)(&tsk->thread.fpu.hard.status)), - "r" (FPSCR_RCHG), - "r" (FPSCR_INIT) - : "memory"); + asm volatile ("sts.l fpul, @-%0\n\t" + "sts.l fpscr, @-%0\n\t" + "lds %2, fpscr\n\t" + "frchg\n\t" + "fmov.s fr15, @-%0\n\t" + "fmov.s fr14, @-%0\n\t" + "fmov.s fr13, @-%0\n\t" + "fmov.s fr12, @-%0\n\t" + "fmov.s fr11, @-%0\n\t" + "fmov.s fr10, @-%0\n\t" + "fmov.s fr9, @-%0\n\t" + "fmov.s fr8, @-%0\n\t" + "fmov.s fr7, @-%0\n\t" + "fmov.s fr6, @-%0\n\t" + "fmov.s fr5, @-%0\n\t" + "fmov.s fr4, @-%0\n\t" + "fmov.s fr3, @-%0\n\t" + "fmov.s fr2, @-%0\n\t" + "fmov.s fr1, @-%0\n\t" + "fmov.s fr0, @-%0\n\t" + "frchg\n\t" + "fmov.s fr15, @-%0\n\t" + "fmov.s fr14, @-%0\n\t" + "fmov.s fr13, @-%0\n\t" + "fmov.s fr12, @-%0\n\t" + "fmov.s fr11, @-%0\n\t" + "fmov.s fr10, @-%0\n\t" + "fmov.s fr9, @-%0\n\t" + "fmov.s fr8, @-%0\n\t" + "fmov.s fr7, @-%0\n\t" + "fmov.s fr6, @-%0\n\t" + "fmov.s fr5, @-%0\n\t" + "fmov.s fr4, @-%0\n\t" + "fmov.s fr3, @-%0\n\t" + "fmov.s fr2, @-%0\n\t" + "fmov.s fr1, @-%0\n\t" + "fmov.s fr0, @-%0\n\t" + "lds %3, fpscr\n\t":"=r" (dummy) + :"0"((char *)(&tsk->thread.fpu.hard.status)), + "r"(FPSCR_RCHG), "r"(FPSCR_INIT) + :"memory"); disable_fpu(); release_fpu(regs); } -static void -restore_fpu(struct task_struct *tsk) +static void restore_fpu(struct task_struct *tsk) { unsigned long dummy; enable_fpu(); - asm volatile("lds %2, fpscr\n\t" - "fmov.s @%0+, fr0\n\t" - "fmov.s @%0+, fr1\n\t" - "fmov.s @%0+, fr2\n\t" - "fmov.s @%0+, fr3\n\t" - "fmov.s @%0+, fr4\n\t" - "fmov.s @%0+, fr5\n\t" - "fmov.s @%0+, fr6\n\t" - "fmov.s @%0+, fr7\n\t" - "fmov.s @%0+, fr8\n\t" - "fmov.s @%0+, fr9\n\t" - "fmov.s @%0+, fr10\n\t" - "fmov.s @%0+, fr11\n\t" - "fmov.s @%0+, fr12\n\t" - "fmov.s @%0+, fr13\n\t" - "fmov.s @%0+, fr14\n\t" - "fmov.s @%0+, fr15\n\t" - "frchg\n\t" - "fmov.s @%0+, fr0\n\t" - "fmov.s @%0+, fr1\n\t" - "fmov.s @%0+, fr2\n\t" - "fmov.s @%0+, fr3\n\t" - "fmov.s @%0+, fr4\n\t" - "fmov.s @%0+, fr5\n\t" - "fmov.s @%0+, fr6\n\t" - "fmov.s @%0+, fr7\n\t" - "fmov.s @%0+, fr8\n\t" - "fmov.s @%0+, fr9\n\t" - "fmov.s @%0+, fr10\n\t" - "fmov.s @%0+, fr11\n\t" - "fmov.s @%0+, fr12\n\t" - "fmov.s @%0+, fr13\n\t" - "fmov.s @%0+, fr14\n\t" - "fmov.s @%0+, fr15\n\t" - "frchg\n\t" - "lds.l @%0+, fpscr\n\t" - "lds.l @%0+, fpul\n\t" - : "=r" (dummy) - : "0" (&tsk->thread.fpu), "r" (FPSCR_RCHG) - : "memory"); + asm volatile ("lds %2, fpscr\n\t" + "fmov.s @%0+, fr0\n\t" + "fmov.s @%0+, fr1\n\t" + "fmov.s @%0+, fr2\n\t" + "fmov.s @%0+, fr3\n\t" + "fmov.s @%0+, fr4\n\t" + "fmov.s @%0+, fr5\n\t" + "fmov.s @%0+, fr6\n\t" + "fmov.s @%0+, fr7\n\t" + "fmov.s @%0+, fr8\n\t" + "fmov.s @%0+, fr9\n\t" + "fmov.s @%0+, fr10\n\t" + "fmov.s @%0+, fr11\n\t" + "fmov.s @%0+, fr12\n\t" + "fmov.s @%0+, fr13\n\t" + "fmov.s @%0+, fr14\n\t" + "fmov.s @%0+, fr15\n\t" + "frchg\n\t" + "fmov.s @%0+, fr0\n\t" + "fmov.s @%0+, fr1\n\t" + "fmov.s @%0+, fr2\n\t" + "fmov.s @%0+, fr3\n\t" + "fmov.s @%0+, fr4\n\t" + "fmov.s @%0+, fr5\n\t" + "fmov.s @%0+, fr6\n\t" + "fmov.s @%0+, fr7\n\t" + "fmov.s @%0+, fr8\n\t" + "fmov.s @%0+, fr9\n\t" + "fmov.s @%0+, fr10\n\t" + "fmov.s @%0+, fr11\n\t" + "fmov.s @%0+, fr12\n\t" + "fmov.s @%0+, fr13\n\t" + "fmov.s @%0+, fr14\n\t" + "fmov.s @%0+, fr15\n\t" + "frchg\n\t" + "lds.l @%0+, fpscr\n\t" + "lds.l @%0+, fpul\n\t" + :"=r" (dummy) + :"0"(&tsk->thread.fpu), "r"(FPSCR_RCHG) + :"memory"); disable_fpu(); } @@ -141,61 +148,59 @@ restore_fpu(struct task_struct *tsk) * double precision represents signaling NANS. */ -static void -fpu_init(void) +static void fpu_init(void) { enable_fpu(); - asm volatile("lds %0, fpul\n\t" - "lds %1, fpscr\n\t" - "fsts fpul, fr0\n\t" - "fsts fpul, fr1\n\t" - "fsts fpul, fr2\n\t" - "fsts fpul, fr3\n\t" - "fsts fpul, fr4\n\t" - "fsts fpul, fr5\n\t" - "fsts fpul, fr6\n\t" - "fsts fpul, fr7\n\t" - "fsts fpul, fr8\n\t" - "fsts fpul, fr9\n\t" - "fsts fpul, fr10\n\t" - "fsts fpul, fr11\n\t" - "fsts fpul, fr12\n\t" - "fsts fpul, fr13\n\t" - "fsts fpul, fr14\n\t" - "fsts fpul, fr15\n\t" - "frchg\n\t" - "fsts fpul, fr0\n\t" - "fsts fpul, fr1\n\t" - "fsts fpul, fr2\n\t" - "fsts fpul, fr3\n\t" - "fsts fpul, fr4\n\t" - "fsts fpul, fr5\n\t" - "fsts fpul, fr6\n\t" - "fsts fpul, fr7\n\t" - "fsts fpul, fr8\n\t" - "fsts fpul, fr9\n\t" - "fsts fpul, fr10\n\t" - "fsts fpul, fr11\n\t" - "fsts fpul, fr12\n\t" - "fsts fpul, fr13\n\t" - "fsts fpul, fr14\n\t" - "fsts fpul, fr15\n\t" - "frchg\n\t" - "lds %2, fpscr\n\t" - : /* no output */ - : "r" (0), "r" (FPSCR_RCHG), "r" (FPSCR_INIT)); + asm volatile ( "lds %0, fpul\n\t" + "lds %1, fpscr\n\t" + "fsts fpul, fr0\n\t" + "fsts fpul, fr1\n\t" + "fsts fpul, fr2\n\t" + "fsts fpul, fr3\n\t" + "fsts fpul, fr4\n\t" + "fsts fpul, fr5\n\t" + "fsts fpul, fr6\n\t" + "fsts fpul, fr7\n\t" + "fsts fpul, fr8\n\t" + "fsts fpul, fr9\n\t" + "fsts fpul, fr10\n\t" + "fsts fpul, fr11\n\t" + "fsts fpul, fr12\n\t" + "fsts fpul, fr13\n\t" + "fsts fpul, fr14\n\t" + "fsts fpul, fr15\n\t" + "frchg\n\t" + "fsts fpul, fr0\n\t" + "fsts fpul, fr1\n\t" + "fsts fpul, fr2\n\t" + "fsts fpul, fr3\n\t" + "fsts fpul, fr4\n\t" + "fsts fpul, fr5\n\t" + "fsts fpul, fr6\n\t" + "fsts fpul, fr7\n\t" + "fsts fpul, fr8\n\t" + "fsts fpul, fr9\n\t" + "fsts fpul, fr10\n\t" + "fsts fpul, fr11\n\t" + "fsts fpul, fr12\n\t" + "fsts fpul, fr13\n\t" + "fsts fpul, fr14\n\t" + "fsts fpul, fr15\n\t" + "frchg\n\t" + "lds %2, fpscr\n\t" + : /* no output */ + :"r" (0), "r"(FPSCR_RCHG), "r"(FPSCR_INIT)); disable_fpu(); } /** - * denormal_to_double - Given denormalized float number, - * store double float + * denormal_to_double - Given denormalized float number, + * store double float * - * @fpu: Pointer to sh_fpu_hard structure - * @n: Index to FP register + * @fpu: Pointer to sh_fpu_hard structure + * @n: Index to FP register */ -static void -denormal_to_double (struct sh_fpu_hard_struct *fpu, int n) +static void denormal_to_double(struct sh_fpu_hard_struct *fpu, int n) { unsigned long du, dl; unsigned long x = fpu->fpul; @@ -212,7 +217,7 @@ denormal_to_double (struct sh_fpu_hard_struct *fpu, int n) dl = x << 29; fpu->fp_regs[n] = du; - fpu->fp_regs[n+1] = dl; + fpu->fp_regs[n + 1] = dl; } } @@ -223,67 +228,191 @@ denormal_to_double (struct sh_fpu_hard_struct *fpu, int n) * * Returns 1 when it's handled (should not cause exception). */ -static int -ieee_fpe_handler (struct pt_regs *regs) +static int ieee_fpe_handler(struct pt_regs *regs) { - unsigned short insn = *(unsigned short *) regs->pc; + unsigned short insn = *(unsigned short *)regs->pc; unsigned short finsn; unsigned long nextpc; int nib[4] = { (insn >> 12) & 0xf, (insn >> 8) & 0xf, (insn >> 4) & 0xf, - insn & 0xf}; - - if (nib[0] == 0xb || - (nib[0] == 0x4 && nib[2] == 0x0 && nib[3] == 0xb)) /* bsr & jsr */ - regs->pr = regs->pc + 4; - if (nib[0] == 0xa || nib[0] == 0xb) { /* bra & bsr */ - nextpc = regs->pc + 4 + ((short) ((insn & 0xfff) << 4) >> 3); - finsn = *(unsigned short *) (regs->pc + 2); - } else if (nib[0] == 0x8 && nib[1] == 0xd) { /* bt/s */ + insn & 0xf + }; + + if (nib[0] == 0xb || (nib[0] == 0x4 && nib[2] == 0x0 && nib[3] == 0xb)) + regs->pr = regs->pc + 4; /* bsr & jsr */ + + if (nib[0] == 0xa || nib[0] == 0xb) { + /* bra & bsr */ + nextpc = regs->pc + 4 + ((short)((insn & 0xfff) << 4) >> 3); + finsn = *(unsigned short *)(regs->pc + 2); + } else if (nib[0] == 0x8 && nib[1] == 0xd) { + /* bt/s */ if (regs->sr & 1) - nextpc = regs->pc + 4 + ((char) (insn & 0xff) << 1); + nextpc = regs->pc + 4 + ((char)(insn & 0xff) << 1); else nextpc = regs->pc + 4; - finsn = *(unsigned short *) (regs->pc + 2); - } else if (nib[0] == 0x8 && nib[1] == 0xf) { /* bf/s */ + finsn = *(unsigned short *)(regs->pc + 2); + } else if (nib[0] == 0x8 && nib[1] == 0xf) { + /* bf/s */ if (regs->sr & 1) nextpc = regs->pc + 4; else - nextpc = regs->pc + 4 + ((char) (insn & 0xff) << 1); - finsn = *(unsigned short *) (regs->pc + 2); + nextpc = regs->pc + 4 + ((char)(insn & 0xff) << 1); + finsn = *(unsigned short *)(regs->pc + 2); } else if (nib[0] == 0x4 && nib[3] == 0xb && - (nib[2] == 0x0 || nib[2] == 0x2)) { /* jmp & jsr */ + (nib[2] == 0x0 || nib[2] == 0x2)) { + /* jmp & jsr */ nextpc = regs->regs[nib[1]]; - finsn = *(unsigned short *) (regs->pc + 2); + finsn = *(unsigned short *)(regs->pc + 2); } else if (nib[0] == 0x0 && nib[3] == 0x3 && - (nib[2] == 0x0 || nib[2] == 0x2)) { /* braf & bsrf */ + (nib[2] == 0x0 || nib[2] == 0x2)) { + /* braf & bsrf */ nextpc = regs->pc + 4 + regs->regs[nib[1]]; - finsn = *(unsigned short *) (regs->pc + 2); - } else if (insn == 0x000b) { /* rts */ + finsn = *(unsigned short *)(regs->pc + 2); + } else if (insn == 0x000b) { + /* rts */ nextpc = regs->pr; - finsn = *(unsigned short *) (regs->pc + 2); + finsn = *(unsigned short *)(regs->pc + 2); } else { nextpc = regs->pc + instruction_size(insn); finsn = insn; } - if ((finsn & 0xf1ff) == 0xf0ad) { /* fcnvsd */ + if ((finsn & 0xf1ff) == 0xf0ad) { + /* fcnvsd */ struct task_struct *tsk = current; save_fpu(tsk, regs); - if ((tsk->thread.fpu.hard.fpscr & (1 << 17))) { + if ((tsk->thread.fpu.hard.fpscr & FPSCR_CAUSE_ERROR)) /* FPU error */ - denormal_to_double (&tsk->thread.fpu.hard, - (finsn >> 8) & 0xf); - tsk->thread.fpu.hard.fpscr &= - ~(FPSCR_CAUSE_MASK | FPSCR_FLAG_MASK); - grab_fpu(regs); - restore_fpu(tsk); - set_tsk_thread_flag(tsk, TIF_USEDFPU); + denormal_to_double(&tsk->thread.fpu.hard, + (finsn >> 8) & 0xf); + else + return 0; + + regs->pc = nextpc; + return 1; + } else if ((finsn & 0xf00f) == 0xf002) { + /* fmul */ + struct task_struct *tsk = current; + int fpscr; + int n, m, prec; + unsigned int hx, hy; + + n = (finsn >> 8) & 0xf; + m = (finsn >> 4) & 0xf; + hx = tsk->thread.fpu.hard.fp_regs[n]; + hy = tsk->thread.fpu.hard.fp_regs[m]; + fpscr = tsk->thread.fpu.hard.fpscr; + prec = fpscr & FPSCR_DBL_PRECISION; + + if ((fpscr & FPSCR_CAUSE_ERROR) + && (prec && ((hx & 0x7fffffff) < 0x00100000 + || (hy & 0x7fffffff) < 0x00100000))) { + long long llx, lly; + + /* FPU error because of denormal (doubles) */ + llx = ((long long)hx << 32) + | tsk->thread.fpu.hard.fp_regs[n + 1]; + lly = ((long long)hy << 32) + | tsk->thread.fpu.hard.fp_regs[m + 1]; + llx = float64_mul(llx, lly); + tsk->thread.fpu.hard.fp_regs[n] = llx >> 32; + tsk->thread.fpu.hard.fp_regs[n + 1] = llx & 0xffffffff; + } else if ((fpscr & FPSCR_CAUSE_ERROR) + && (!prec && ((hx & 0x7fffffff) < 0x00800000 + || (hy & 0x7fffffff) < 0x00800000))) { + /* FPU error because of denormal (floats) */ + hx = float32_mul(hx, hy); + tsk->thread.fpu.hard.fp_regs[n] = hx; + } else + return 0; + + regs->pc = nextpc; + return 1; + } else if ((finsn & 0xf00e) == 0xf000) { + /* fadd, fsub */ + struct task_struct *tsk = current; + int fpscr; + int n, m, prec; + unsigned int hx, hy; + + n = (finsn >> 8) & 0xf; + m = (finsn >> 4) & 0xf; + hx = tsk->thread.fpu.hard.fp_regs[n]; + hy = tsk->thread.fpu.hard.fp_regs[m]; + fpscr = tsk->thread.fpu.hard.fpscr; + prec = fpscr & FPSCR_DBL_PRECISION; + + if ((fpscr & FPSCR_CAUSE_ERROR) + && (prec && ((hx & 0x7fffffff) < 0x00100000 + || (hy & 0x7fffffff) < 0x00100000))) { + long long llx, lly; + + /* FPU error because of denormal (doubles) */ + llx = ((long long)hx << 32) + | tsk->thread.fpu.hard.fp_regs[n + 1]; + lly = ((long long)hy << 32) + | tsk->thread.fpu.hard.fp_regs[m + 1]; + if ((finsn & 0xf00f) == 0xf000) + llx = float64_add(llx, lly); + else + llx = float64_sub(llx, lly); + tsk->thread.fpu.hard.fp_regs[n] = llx >> 32; + tsk->thread.fpu.hard.fp_regs[n + 1] = llx & 0xffffffff; + } else if ((fpscr & FPSCR_CAUSE_ERROR) + && (!prec && ((hx & 0x7fffffff) < 0x00800000 + || (hy & 0x7fffffff) < 0x00800000))) { + /* FPU error because of denormal (floats) */ + if ((finsn & 0xf00f) == 0xf000) + hx = float32_add(hx, hy); + else + hx = float32_sub(hx, hy); + tsk->thread.fpu.hard.fp_regs[n] = hx; + } else + return 0; + + regs->pc = nextpc; + return 1; + } else if ((finsn & 0xf003) == 0xf003) { + /* fdiv */ + struct task_struct *tsk = current; + int fpscr; + int n, m, prec; + unsigned int hx, hy; + + n = (finsn >> 8) & 0xf; + m = (finsn >> 4) & 0xf; + hx = tsk->thread.fpu.hard.fp_regs[n]; + hy = tsk->thread.fpu.hard.fp_regs[m]; + fpscr = tsk->thread.fpu.hard.fpscr; + prec = fpscr & FPSCR_DBL_PRECISION; + + if ((fpscr & FPSCR_CAUSE_ERROR) + && (prec && ((hx & 0x7fffffff) < 0x00100000 + || (hy & 0x7fffffff) < 0x00100000))) { + long long llx, lly; + + /* FPU error because of denormal (doubles) */ + llx = ((long long)hx << 32) + | tsk->thread.fpu.hard.fp_regs[n + 1]; + lly = ((long long)hy << 32) + | tsk->thread.fpu.hard.fp_regs[m + 1]; + + llx = float64_div(llx, lly); + + tsk->thread.fpu.hard.fp_regs[n] = llx >> 32; + tsk->thread.fpu.hard.fp_regs[n + 1] = llx & 0xffffffff; + } else if ((fpscr & FPSCR_CAUSE_ERROR) + && (!prec && ((hx & 0x7fffffff) < 0x00800000 + || (hy & 0x7fffffff) < 0x00800000))) { + /* FPU error because of denormal (floats) */ + hx = float32_div(hx, hy); + tsk->thread.fpu.hard.fp_regs[n] = hx; } else - force_sig(SIGFPE, tsk); + return 0; regs->pc = nextpc; return 1; @@ -292,16 +421,41 @@ ieee_fpe_handler (struct pt_regs *regs) return 0; } +void float_raise(unsigned int flags) +{ + fpu_exception_flags |= flags; +} + +int float_rounding_mode(void) +{ + struct task_struct *tsk = current; + int roundingMode = FPSCR_ROUNDING_MODE(tsk->thread.fpu.hard.fpscr); + return roundingMode; +} + BUILD_TRAP_HANDLER(fpu_error) { struct task_struct *tsk = current; TRAP_HANDLER_DECL; - if (ieee_fpe_handler(regs)) - return; - - regs->pc += 2; save_fpu(tsk, regs); + fpu_exception_flags = 0; + if (ieee_fpe_handler(regs)) { + tsk->thread.fpu.hard.fpscr &= + ~(FPSCR_CAUSE_MASK | FPSCR_FLAG_MASK); + tsk->thread.fpu.hard.fpscr |= fpu_exception_flags; + /* Set the FPSCR flag as well as cause bits - simply + * replicate the cause */ + tsk->thread.fpu.hard.fpscr |= (fpu_exception_flags >> 10); + grab_fpu(regs); + restore_fpu(tsk); + set_tsk_thread_flag(tsk, TIF_USEDFPU); + if ((((tsk->thread.fpu.hard.fpscr & FPSCR_ENABLE_MASK) >> 7) & + (fpu_exception_flags >> 2)) == 0) { + return; + } + } + force_sig(SIGFPE, tsk); } @@ -319,7 +473,7 @@ BUILD_TRAP_HANDLER(fpu_state_restore) if (used_math()) { /* Using the FPU again. */ restore_fpu(tsk); - } else { + } else { /* First time FPU user. */ fpu_init(); set_used_math(); |
