624 lines
13 KiB
C
624 lines
13 KiB
C
/*
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* arch/sh/math-emu/math.c
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*
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* Copyright (C) 2006 Takashi YOSHII <takasi-y@ops.dti.ne.jp>
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*
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* This file is subject to the terms and conditions of the GNU General Public
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* License. See the file "COPYING" in the main directory of this archive
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* for more details.
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*/
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#include <linux/kernel.h>
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#include <linux/errno.h>
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#include <linux/types.h>
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#include <linux/sched.h>
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#include <linux/signal.h>
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#include <asm/system.h>
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#include <asm/uaccess.h>
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#include <asm/processor.h>
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#include <asm/io.h>
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#include "sfp-util.h"
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#include <math-emu/soft-fp.h>
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#include <math-emu/single.h>
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#include <math-emu/double.h>
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#define FPUL (fregs->fpul)
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#define FPSCR (fregs->fpscr)
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#define FPSCR_RM (FPSCR&3)
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#define FPSCR_DN ((FPSCR>>18)&1)
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#define FPSCR_PR ((FPSCR>>19)&1)
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#define FPSCR_SZ ((FPSCR>>20)&1)
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#define FPSCR_FR ((FPSCR>>21)&1)
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#define FPSCR_MASK 0x003fffffUL
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#define BANK(n) (n^(FPSCR_FR?16:0))
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#define FR ((unsigned long*)(fregs->fp_regs))
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#define FR0 (FR[BANK(0)])
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#define FRn (FR[BANK(n)])
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#define FRm (FR[BANK(m)])
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#define DR ((unsigned long long*)(fregs->fp_regs))
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#define DRn (DR[BANK(n)/2])
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#define DRm (DR[BANK(m)/2])
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#define XREG(n) (n^16)
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#define XFn (FR[BANK(XREG(n))])
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#define XFm (FR[BANK(XREG(m))])
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#define XDn (DR[BANK(XREG(n))/2])
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#define XDm (DR[BANK(XREG(m))/2])
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#define R0 (regs->regs[0])
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#define Rn (regs->regs[n])
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#define Rm (regs->regs[m])
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#define WRITE(d,a) ({if(put_user(d, (typeof (d)*)a)) return -EFAULT;})
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#define READ(d,a) ({if(get_user(d, (typeof (d)*)a)) return -EFAULT;})
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#define PACK_S(r,f) FP_PACK_SP(&r,f)
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#define UNPACK_S(f,r) FP_UNPACK_SP(f,&r)
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#define PACK_D(r,f) \
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{u32 t[2]; FP_PACK_DP(t,f); ((u32*)&r)[0]=t[1]; ((u32*)&r)[1]=t[0];}
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#define UNPACK_D(f,r) \
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{u32 t[2]; t[0]=((u32*)&r)[1]; t[1]=((u32*)&r)[0]; FP_UNPACK_DP(f,t);}
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// 2 args instructions.
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#define BOTH_PRmn(op,x) \
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FP_DECL_EX; if(FPSCR_PR) op(D,x,DRm,DRn); else op(S,x,FRm,FRn);
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#define CMP_X(SZ,R,M,N) do{ \
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FP_DECL_##SZ(Fm); FP_DECL_##SZ(Fn); \
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UNPACK_##SZ(Fm, M); UNPACK_##SZ(Fn, N); \
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FP_CMP_##SZ(R, Fn, Fm, 2); }while(0)
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#define EQ_X(SZ,R,M,N) do{ \
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FP_DECL_##SZ(Fm); FP_DECL_##SZ(Fn); \
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UNPACK_##SZ(Fm, M); UNPACK_##SZ(Fn, N); \
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FP_CMP_EQ_##SZ(R, Fn, Fm); }while(0)
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#define CMP(OP) ({ int r; BOTH_PRmn(OP##_X,r); r; })
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static int
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fcmp_gt(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n)
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{
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if (CMP(CMP) > 0)
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regs->sr |= 1;
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else
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regs->sr &= ~1;
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return 0;
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}
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static int
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fcmp_eq(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n)
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{
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if (CMP(CMP /*EQ*/) == 0)
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regs->sr |= 1;
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else
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regs->sr &= ~1;
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return 0;
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}
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#define ARITH_X(SZ,OP,M,N) do{ \
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FP_DECL_##SZ(Fm); FP_DECL_##SZ(Fn); FP_DECL_##SZ(Fr); \
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UNPACK_##SZ(Fm, M); UNPACK_##SZ(Fn, N); \
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FP_##OP##_##SZ(Fr, Fn, Fm); \
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PACK_##SZ(N, Fr); }while(0)
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static int
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fadd(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n)
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{
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BOTH_PRmn(ARITH_X, ADD);
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return 0;
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}
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static int
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fsub(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n)
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{
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BOTH_PRmn(ARITH_X, SUB);
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return 0;
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}
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static int
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fmul(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n)
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{
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BOTH_PRmn(ARITH_X, MUL);
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return 0;
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}
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static int
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fdiv(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n)
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{
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BOTH_PRmn(ARITH_X, DIV);
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return 0;
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}
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static int
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fmac(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n)
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{
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FP_DECL_EX;
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FP_DECL_S(Fr);
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FP_DECL_S(Ft);
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FP_DECL_S(F0);
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FP_DECL_S(Fm);
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FP_DECL_S(Fn);
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UNPACK_S(F0, FR0);
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UNPACK_S(Fm, FRm);
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UNPACK_S(Fn, FRn);
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FP_MUL_S(Ft, Fm, F0);
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FP_ADD_S(Fr, Fn, Ft);
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PACK_S(FRn, Fr);
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return 0;
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}
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// to process fmov's extention (odd n for DR access XD).
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#define FMOV_EXT(x) if(x&1) x+=16-1
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static int
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fmov_idx_reg(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m,
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int n)
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{
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if (FPSCR_SZ) {
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FMOV_EXT(n);
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READ(FRn, Rm + R0 + 4);
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n++;
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READ(FRn, Rm + R0);
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} else {
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READ(FRn, Rm + R0);
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}
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return 0;
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}
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static int
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fmov_mem_reg(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m,
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int n)
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{
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if (FPSCR_SZ) {
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FMOV_EXT(n);
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READ(FRn, Rm + 4);
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n++;
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READ(FRn, Rm);
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} else {
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READ(FRn, Rm);
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}
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return 0;
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}
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static int
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fmov_inc_reg(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m,
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int n)
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{
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if (FPSCR_SZ) {
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FMOV_EXT(n);
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READ(FRn, Rm + 4);
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n++;
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READ(FRn, Rm);
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Rm += 8;
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} else {
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READ(FRn, Rm);
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Rm += 4;
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}
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return 0;
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}
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static int
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fmov_reg_idx(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m,
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int n)
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{
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if (FPSCR_SZ) {
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FMOV_EXT(m);
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WRITE(FRm, Rn + R0 + 4);
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m++;
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WRITE(FRm, Rn + R0);
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} else {
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WRITE(FRm, Rn + R0);
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}
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return 0;
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}
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static int
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fmov_reg_mem(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m,
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int n)
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{
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if (FPSCR_SZ) {
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FMOV_EXT(m);
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WRITE(FRm, Rn + 4);
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m++;
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WRITE(FRm, Rn);
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} else {
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WRITE(FRm, Rn);
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}
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return 0;
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}
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static int
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fmov_reg_dec(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m,
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int n)
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{
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if (FPSCR_SZ) {
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FMOV_EXT(m);
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Rn -= 8;
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WRITE(FRm, Rn + 4);
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m++;
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WRITE(FRm, Rn);
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} else {
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Rn -= 4;
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WRITE(FRm, Rn);
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}
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return 0;
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}
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static int
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fmov_reg_reg(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m,
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int n)
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{
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if (FPSCR_SZ) {
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FMOV_EXT(m);
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FMOV_EXT(n);
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DRn = DRm;
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} else {
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FRn = FRm;
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}
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return 0;
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}
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static int
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fnop_mn(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n)
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{
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return -EINVAL;
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}
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// 1 arg instructions.
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#define NOTYETn(i) static int i(struct sh_fpu_soft_struct *fregs, int n) \
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{ printk( #i " not yet done.\n"); return 0; }
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NOTYETn(ftrv)
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NOTYETn(fsqrt)
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NOTYETn(fipr)
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NOTYETn(fsca)
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NOTYETn(fsrra)
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#define EMU_FLOAT_X(SZ,N) do { \
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FP_DECL_##SZ(Fn); \
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FP_FROM_INT_##SZ(Fn, FPUL, 32, int); \
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PACK_##SZ(N, Fn); }while(0)
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static int ffloat(struct sh_fpu_soft_struct *fregs, int n)
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{
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FP_DECL_EX;
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if (FPSCR_PR)
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EMU_FLOAT_X(D, DRn);
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else
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EMU_FLOAT_X(S, FRn);
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return 0;
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}
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#define EMU_FTRC_X(SZ,N) do { \
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FP_DECL_##SZ(Fn); \
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UNPACK_##SZ(Fn, N); \
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FP_TO_INT_##SZ(FPUL, Fn, 32, 1); }while(0)
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static int ftrc(struct sh_fpu_soft_struct *fregs, int n)
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{
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FP_DECL_EX;
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if (FPSCR_PR)
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EMU_FTRC_X(D, DRn);
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else
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EMU_FTRC_X(S, FRn);
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return 0;
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}
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static int fcnvsd(struct sh_fpu_soft_struct *fregs, int n)
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{
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FP_DECL_EX;
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FP_DECL_S(Fn);
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FP_DECL_D(Fr);
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UNPACK_S(Fn, FPUL);
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FP_CONV(D, S, 2, 1, Fr, Fn);
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PACK_D(DRn, Fr);
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return 0;
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}
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static int fcnvds(struct sh_fpu_soft_struct *fregs, int n)
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{
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FP_DECL_EX;
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FP_DECL_D(Fn);
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FP_DECL_S(Fr);
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UNPACK_D(Fn, DRn);
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FP_CONV(S, D, 1, 2, Fr, Fn);
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PACK_S(FPUL, Fr);
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return 0;
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}
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static int fxchg(struct sh_fpu_soft_struct *fregs, int flag)
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{
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FPSCR ^= flag;
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return 0;
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}
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static int fsts(struct sh_fpu_soft_struct *fregs, int n)
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{
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FRn = FPUL;
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return 0;
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}
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static int flds(struct sh_fpu_soft_struct *fregs, int n)
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{
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FPUL = FRn;
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return 0;
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}
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static int fneg(struct sh_fpu_soft_struct *fregs, int n)
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{
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FRn ^= (1 << (_FP_W_TYPE_SIZE - 1));
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return 0;
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}
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static int fabs(struct sh_fpu_soft_struct *fregs, int n)
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{
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FRn &= ~(1 << (_FP_W_TYPE_SIZE - 1));
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return 0;
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}
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static int fld0(struct sh_fpu_soft_struct *fregs, int n)
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{
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FRn = 0;
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return 0;
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}
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static int fld1(struct sh_fpu_soft_struct *fregs, int n)
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{
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FRn = (_FP_EXPBIAS_S << (_FP_FRACBITS_S - 1));
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return 0;
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}
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static int fnop_n(struct sh_fpu_soft_struct *fregs, int n)
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{
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return -EINVAL;
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}
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/// Instruction decoders.
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static int id_fxfd(struct sh_fpu_soft_struct *, int);
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static int id_fnxd(struct sh_fpu_soft_struct *, struct pt_regs *, int, int);
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static int (*fnxd[])(struct sh_fpu_soft_struct *, int) = {
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fsts, flds, ffloat, ftrc, fneg, fabs, fsqrt, fsrra,
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fld0, fld1, fcnvsd, fcnvds, fnop_n, fnop_n, fipr, id_fxfd
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};
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static int (*fnmx[])(struct sh_fpu_soft_struct *, struct pt_regs *, int, int) = {
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fadd, fsub, fmul, fdiv, fcmp_eq, fcmp_gt, fmov_idx_reg, fmov_reg_idx,
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fmov_mem_reg, fmov_inc_reg, fmov_reg_mem, fmov_reg_dec,
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fmov_reg_reg, id_fnxd, fmac, fnop_mn};
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static int id_fxfd(struct sh_fpu_soft_struct *fregs, int x)
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{
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const int flag[] = { FPSCR_SZ, FPSCR_PR, FPSCR_FR, 0 };
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switch (x & 3) {
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case 3:
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fxchg(fregs, flag[x >> 2]);
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break;
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case 1:
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ftrv(fregs, x - 1);
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break;
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default:
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fsca(fregs, x);
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}
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return 0;
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}
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static int
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id_fnxd(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int x, int n)
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{
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return (fnxd[x])(fregs, n);
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}
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static int
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id_fnmx(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, u16 code)
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{
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int n = (code >> 8) & 0xf, m = (code >> 4) & 0xf, x = code & 0xf;
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return (fnmx[x])(fregs, regs, m, n);
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}
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static int
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id_sys(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, u16 code)
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{
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int n = ((code >> 8) & 0xf);
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unsigned long *reg = (code & 0x0010) ? &FPUL : &FPSCR;
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switch (code & 0xf0ff) {
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case 0x005a:
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case 0x006a:
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Rn = *reg;
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break;
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case 0x405a:
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case 0x406a:
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*reg = Rn;
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break;
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case 0x4052:
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case 0x4062:
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Rn -= 4;
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WRITE(*reg, Rn);
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break;
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case 0x4056:
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case 0x4066:
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READ(*reg, Rn);
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Rn += 4;
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break;
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default:
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return -EINVAL;
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}
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return 0;
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}
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static int fpu_emulate(u16 code, struct sh_fpu_soft_struct *fregs, struct pt_regs *regs)
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{
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if ((code & 0xf000) == 0xf000)
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return id_fnmx(fregs, regs, code);
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else
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return id_sys(fregs, regs, code);
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}
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/**
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* denormal_to_double - Given denormalized float number,
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* store double float
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*
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* @fpu: Pointer to sh_fpu_hard structure
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* @n: Index to FP register
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*/
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static void denormal_to_double(struct sh_fpu_hard_struct *fpu, int n)
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{
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unsigned long du, dl;
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unsigned long x = fpu->fpul;
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int exp = 1023 - 126;
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if (x != 0 && (x & 0x7f800000) == 0) {
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du = (x & 0x80000000);
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while ((x & 0x00800000) == 0) {
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x <<= 1;
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exp--;
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}
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x &= 0x007fffff;
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du |= (exp << 20) | (x >> 3);
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dl = x << 29;
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fpu->fp_regs[n] = du;
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fpu->fp_regs[n+1] = dl;
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}
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}
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/**
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* ieee_fpe_handler - Handle denormalized number exception
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*
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* @regs: Pointer to register structure
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*
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* Returns 1 when it's handled (should not cause exception).
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*/
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static int ieee_fpe_handler(struct pt_regs *regs)
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{
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unsigned short insn = *(unsigned short *)regs->pc;
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unsigned short finsn;
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unsigned long nextpc;
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int nib[4] = {
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(insn >> 12) & 0xf,
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(insn >> 8) & 0xf,
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(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 */
|
|
if (regs->sr & 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 */
|
|
if (regs->sr & 1)
|
|
nextpc = regs->pc + 4;
|
|
else
|
|
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 */
|
|
nextpc = regs->regs[nib[1]];
|
|
finsn = *(unsigned short *) (regs->pc + 2);
|
|
} else if (nib[0] == 0x0 && nib[3] == 0x3 &&
|
|
(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 */
|
|
nextpc = regs->pr;
|
|
finsn = *(unsigned short *) (regs->pc + 2);
|
|
} else {
|
|
nextpc = regs->pc + 2;
|
|
finsn = insn;
|
|
}
|
|
|
|
if ((finsn & 0xf1ff) == 0xf0ad) { /* fcnvsd */
|
|
struct task_struct *tsk = current;
|
|
|
|
if ((tsk->thread.fpu.hard.fpscr & (1 << 17))) {
|
|
/* FPU error */
|
|
denormal_to_double (&tsk->thread.fpu.hard,
|
|
(finsn >> 8) & 0xf);
|
|
tsk->thread.fpu.hard.fpscr &=
|
|
~(FPSCR_CAUSE_MASK | FPSCR_FLAG_MASK);
|
|
set_tsk_thread_flag(tsk, TIF_USEDFPU);
|
|
} else {
|
|
tsk->thread.trap_no = 11;
|
|
tsk->thread.error_code = 0;
|
|
force_sig(SIGFPE, tsk);
|
|
}
|
|
|
|
regs->pc = nextpc;
|
|
return 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
asmlinkage void do_fpu_error(unsigned long r4, unsigned long r5,
|
|
unsigned long r6, unsigned long r7,
|
|
struct pt_regs regs)
|
|
{
|
|
struct task_struct *tsk = current;
|
|
|
|
if (ieee_fpe_handler (®s))
|
|
return;
|
|
|
|
regs.pc += 2;
|
|
tsk->thread.trap_no = 11;
|
|
tsk->thread.error_code = 0;
|
|
force_sig(SIGFPE, tsk);
|
|
}
|
|
|
|
/**
|
|
* fpu_init - Initialize FPU registers
|
|
* @fpu: Pointer to software emulated FPU registers.
|
|
*/
|
|
static void fpu_init(struct sh_fpu_soft_struct *fpu)
|
|
{
|
|
int i;
|
|
|
|
fpu->fpscr = FPSCR_INIT;
|
|
fpu->fpul = 0;
|
|
|
|
for (i = 0; i < 16; i++) {
|
|
fpu->fp_regs[i] = 0;
|
|
fpu->xfp_regs[i]= 0;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* do_fpu_inst - Handle reserved instructions for FPU emulation
|
|
* @inst: instruction code.
|
|
* @regs: registers on stack.
|
|
*/
|
|
int do_fpu_inst(unsigned short inst, struct pt_regs *regs)
|
|
{
|
|
struct task_struct *tsk = current;
|
|
struct sh_fpu_soft_struct *fpu = &(tsk->thread.fpu.soft);
|
|
|
|
if (!test_tsk_thread_flag(tsk, TIF_USEDFPU)) {
|
|
/* initialize once. */
|
|
fpu_init(fpu);
|
|
set_tsk_thread_flag(tsk, TIF_USEDFPU);
|
|
}
|
|
|
|
return fpu_emulate(inst, fpu, regs);
|
|
}
|