diff options
Diffstat (limited to 'arch/sh/math-emu/math.c')
| -rw-r--r-- | arch/sh/math-emu/math.c | 631 |
1 files changed, 631 insertions, 0 deletions
diff --git a/arch/sh/math-emu/math.c b/arch/sh/math-emu/math.c new file mode 100644 index 00000000..b876780c --- /dev/null +++ b/arch/sh/math-emu/math.c @@ -0,0 +1,631 @@ +/* + * arch/sh/math-emu/math.c + * + * Copyright (C) 2006 Takashi YOSHII <takasi-y@ops.dti.ne.jp> + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + */ +#include <linux/kernel.h> +#include <linux/errno.h> +#include <linux/types.h> +#include <linux/sched.h> +#include <linux/signal.h> +#include <linux/perf_event.h> + +#include <asm/uaccess.h> +#include <asm/processor.h> +#include <asm/io.h> + +#include "sfp-util.h" +#include <math-emu/soft-fp.h> +#include <math-emu/single.h> +#include <math-emu/double.h> + +#define FPUL (fregs->fpul) +#define FPSCR (fregs->fpscr) +#define FPSCR_RM (FPSCR&3) +#define FPSCR_DN ((FPSCR>>18)&1) +#define FPSCR_PR ((FPSCR>>19)&1) +#define FPSCR_SZ ((FPSCR>>20)&1) +#define FPSCR_FR ((FPSCR>>21)&1) +#define FPSCR_MASK 0x003fffffUL + +#define BANK(n) (n^(FPSCR_FR?16:0)) +#define FR ((unsigned long*)(fregs->fp_regs)) +#define FR0 (FR[BANK(0)]) +#define FRn (FR[BANK(n)]) +#define FRm (FR[BANK(m)]) +#define DR ((unsigned long long*)(fregs->fp_regs)) +#define DRn (DR[BANK(n)/2]) +#define DRm (DR[BANK(m)/2]) + +#define XREG(n) (n^16) +#define XFn (FR[BANK(XREG(n))]) +#define XFm (FR[BANK(XREG(m))]) +#define XDn (DR[BANK(XREG(n))/2]) +#define XDm (DR[BANK(XREG(m))/2]) + +#define R0 (regs->regs[0]) +#define Rn (regs->regs[n]) +#define Rm (regs->regs[m]) + +#define WRITE(d,a) ({if(put_user(d, (typeof (d)*)a)) return -EFAULT;}) +#define READ(d,a) ({if(get_user(d, (typeof (d)*)a)) return -EFAULT;}) + +#define PACK_S(r,f) FP_PACK_SP(&r,f) +#define UNPACK_S(f,r) FP_UNPACK_SP(f,&r) +#define PACK_D(r,f) \ + {u32 t[2]; FP_PACK_DP(t,f); ((u32*)&r)[0]=t[1]; ((u32*)&r)[1]=t[0];} +#define UNPACK_D(f,r) \ + {u32 t[2]; t[0]=((u32*)&r)[1]; t[1]=((u32*)&r)[0]; FP_UNPACK_DP(f,t);} + +// 2 args instructions. +#define BOTH_PRmn(op,x) \ + FP_DECL_EX; if(FPSCR_PR) op(D,x,DRm,DRn); else op(S,x,FRm,FRn); + +#define CMP_X(SZ,R,M,N) do{ \ + FP_DECL_##SZ(Fm); FP_DECL_##SZ(Fn); \ + UNPACK_##SZ(Fm, M); UNPACK_##SZ(Fn, N); \ + FP_CMP_##SZ(R, Fn, Fm, 2); }while(0) +#define EQ_X(SZ,R,M,N) do{ \ + FP_DECL_##SZ(Fm); FP_DECL_##SZ(Fn); \ + UNPACK_##SZ(Fm, M); UNPACK_##SZ(Fn, N); \ + FP_CMP_EQ_##SZ(R, Fn, Fm); }while(0) +#define CMP(OP) ({ int r; BOTH_PRmn(OP##_X,r); r; }) + +static int +fcmp_gt(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n) +{ + if (CMP(CMP) > 0) + regs->sr |= 1; + else + regs->sr &= ~1; + + return 0; +} + +static int +fcmp_eq(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n) +{ + if (CMP(CMP /*EQ*/) == 0) + regs->sr |= 1; + else + regs->sr &= ~1; + return 0; +} + +#define ARITH_X(SZ,OP,M,N) do{ \ + FP_DECL_##SZ(Fm); FP_DECL_##SZ(Fn); FP_DECL_##SZ(Fr); \ + UNPACK_##SZ(Fm, M); UNPACK_##SZ(Fn, N); \ + FP_##OP##_##SZ(Fr, Fn, Fm); \ + PACK_##SZ(N, Fr); }while(0) + +static int +fadd(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n) +{ + BOTH_PRmn(ARITH_X, ADD); + return 0; +} + +static int +fsub(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n) +{ + BOTH_PRmn(ARITH_X, SUB); + return 0; +} + +static int +fmul(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n) +{ + BOTH_PRmn(ARITH_X, MUL); + return 0; +} + +static int +fdiv(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n) +{ + BOTH_PRmn(ARITH_X, DIV); + return 0; +} + +static int +fmac(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n) +{ + FP_DECL_EX; + FP_DECL_S(Fr); + FP_DECL_S(Ft); + FP_DECL_S(F0); + FP_DECL_S(Fm); + FP_DECL_S(Fn); + UNPACK_S(F0, FR0); + UNPACK_S(Fm, FRm); + UNPACK_S(Fn, FRn); + FP_MUL_S(Ft, Fm, F0); + FP_ADD_S(Fr, Fn, Ft); + PACK_S(FRn, Fr); + return 0; +} + +// to process fmov's extension (odd n for DR access XD). +#define FMOV_EXT(x) if(x&1) x+=16-1 + +static int +fmov_idx_reg(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, + int n) +{ + if (FPSCR_SZ) { + FMOV_EXT(n); + READ(FRn, Rm + R0 + 4); + n++; + READ(FRn, Rm + R0); + } else { + READ(FRn, Rm + R0); + } + + return 0; +} + +static int +fmov_mem_reg(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, + int n) +{ + if (FPSCR_SZ) { + FMOV_EXT(n); + READ(FRn, Rm + 4); + n++; + READ(FRn, Rm); + } else { + READ(FRn, Rm); + } + + return 0; +} + +static int +fmov_inc_reg(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, + int n) +{ + if (FPSCR_SZ) { + FMOV_EXT(n); + READ(FRn, Rm + 4); + n++; + READ(FRn, Rm); + Rm += 8; + } else { + READ(FRn, Rm); + Rm += 4; + } + + return 0; +} + +static int +fmov_reg_idx(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, + int n) +{ + if (FPSCR_SZ) { + FMOV_EXT(m); + WRITE(FRm, Rn + R0 + 4); + m++; + WRITE(FRm, Rn + R0); + } else { + WRITE(FRm, Rn + R0); + } + + return 0; +} + +static int +fmov_reg_mem(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, + int n) +{ + if (FPSCR_SZ) { + FMOV_EXT(m); + WRITE(FRm, Rn + 4); + m++; + WRITE(FRm, Rn); + } else { + WRITE(FRm, Rn); + } + + return 0; +} + +static int +fmov_reg_dec(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, + int n) +{ + if (FPSCR_SZ) { + FMOV_EXT(m); + Rn -= 8; + WRITE(FRm, Rn + 4); + m++; + WRITE(FRm, Rn); + } else { + Rn -= 4; + WRITE(FRm, Rn); + } + + return 0; +} + +static int +fmov_reg_reg(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, + int n) +{ + if (FPSCR_SZ) { + FMOV_EXT(m); + FMOV_EXT(n); + DRn = DRm; + } else { + FRn = FRm; + } + + return 0; +} + +static int +fnop_mn(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int m, int n) +{ + return -EINVAL; +} + +// 1 arg instructions. +#define NOTYETn(i) static int i(struct sh_fpu_soft_struct *fregs, int n) \ + { printk( #i " not yet done.\n"); return 0; } + +NOTYETn(ftrv) +NOTYETn(fsqrt) +NOTYETn(fipr) +NOTYETn(fsca) +NOTYETn(fsrra) + +#define EMU_FLOAT_X(SZ,N) do { \ + FP_DECL_##SZ(Fn); \ + FP_FROM_INT_##SZ(Fn, FPUL, 32, int); \ + PACK_##SZ(N, Fn); }while(0) +static int ffloat(struct sh_fpu_soft_struct *fregs, int n) +{ + FP_DECL_EX; + + if (FPSCR_PR) + EMU_FLOAT_X(D, DRn); + else + EMU_FLOAT_X(S, FRn); + + return 0; +} + +#define EMU_FTRC_X(SZ,N) do { \ + FP_DECL_##SZ(Fn); \ + UNPACK_##SZ(Fn, N); \ + FP_TO_INT_##SZ(FPUL, Fn, 32, 1); }while(0) +static int ftrc(struct sh_fpu_soft_struct *fregs, int n) +{ + FP_DECL_EX; + + if (FPSCR_PR) + EMU_FTRC_X(D, DRn); + else + EMU_FTRC_X(S, FRn); + + return 0; +} + +static int fcnvsd(struct sh_fpu_soft_struct *fregs, int n) +{ + FP_DECL_EX; + FP_DECL_S(Fn); + FP_DECL_D(Fr); + UNPACK_S(Fn, FPUL); + FP_CONV(D, S, 2, 1, Fr, Fn); + PACK_D(DRn, Fr); + return 0; +} + +static int fcnvds(struct sh_fpu_soft_struct *fregs, int n) +{ + FP_DECL_EX; + FP_DECL_D(Fn); + FP_DECL_S(Fr); + UNPACK_D(Fn, DRn); + FP_CONV(S, D, 1, 2, Fr, Fn); + PACK_S(FPUL, Fr); + return 0; +} + +static int fxchg(struct sh_fpu_soft_struct *fregs, int flag) +{ + FPSCR ^= flag; + return 0; +} + +static int fsts(struct sh_fpu_soft_struct *fregs, int n) +{ + FRn = FPUL; + return 0; +} + +static int flds(struct sh_fpu_soft_struct *fregs, int n) +{ + FPUL = FRn; + return 0; +} + +static int fneg(struct sh_fpu_soft_struct *fregs, int n) +{ + FRn ^= (1 << (_FP_W_TYPE_SIZE - 1)); + return 0; +} + +static int fabs(struct sh_fpu_soft_struct *fregs, int n) +{ + FRn &= ~(1 << (_FP_W_TYPE_SIZE - 1)); + return 0; +} + +static int fld0(struct sh_fpu_soft_struct *fregs, int n) +{ + FRn = 0; + return 0; +} + +static int fld1(struct sh_fpu_soft_struct *fregs, int n) +{ + FRn = (_FP_EXPBIAS_S << (_FP_FRACBITS_S - 1)); + return 0; +} + +static int fnop_n(struct sh_fpu_soft_struct *fregs, int n) +{ + return -EINVAL; +} + +/// Instruction decoders. + +static int id_fxfd(struct sh_fpu_soft_struct *, int); +static int id_fnxd(struct sh_fpu_soft_struct *, struct pt_regs *, int, int); + +static int (*fnxd[])(struct sh_fpu_soft_struct *, int) = { + fsts, flds, ffloat, ftrc, fneg, fabs, fsqrt, fsrra, + fld0, fld1, fcnvsd, fcnvds, fnop_n, fnop_n, fipr, id_fxfd +}; + +static int (*fnmx[])(struct sh_fpu_soft_struct *, struct pt_regs *, int, int) = { + fadd, fsub, fmul, fdiv, fcmp_eq, fcmp_gt, fmov_idx_reg, fmov_reg_idx, + fmov_mem_reg, fmov_inc_reg, fmov_reg_mem, fmov_reg_dec, + fmov_reg_reg, id_fnxd, fmac, fnop_mn}; + +static int id_fxfd(struct sh_fpu_soft_struct *fregs, int x) +{ + const int flag[] = { FPSCR_SZ, FPSCR_PR, FPSCR_FR, 0 }; + switch (x & 3) { + case 3: + fxchg(fregs, flag[x >> 2]); + break; + case 1: + ftrv(fregs, x - 1); + break; + default: + fsca(fregs, x); + } + return 0; +} + +static int +id_fnxd(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, int x, int n) +{ + return (fnxd[x])(fregs, n); +} + +static int +id_fnmx(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, u16 code) +{ + int n = (code >> 8) & 0xf, m = (code >> 4) & 0xf, x = code & 0xf; + return (fnmx[x])(fregs, regs, m, n); +} + +static int +id_sys(struct sh_fpu_soft_struct *fregs, struct pt_regs *regs, u16 code) +{ + int n = ((code >> 8) & 0xf); + unsigned long *reg = (code & 0x0010) ? &FPUL : &FPSCR; + + switch (code & 0xf0ff) { + case 0x005a: + case 0x006a: + Rn = *reg; + break; + case 0x405a: + case 0x406a: + *reg = Rn; + break; + case 0x4052: + case 0x4062: + Rn -= 4; + WRITE(*reg, Rn); + break; + case 0x4056: + case 0x4066: + READ(*reg, Rn); + Rn += 4; + break; + default: + return -EINVAL; + } + + return 0; +} + +static int fpu_emulate(u16 code, struct sh_fpu_soft_struct *fregs, struct pt_regs *regs) +{ + if ((code & 0xf000) == 0xf000) + return id_fnmx(fregs, regs, code); + else + return id_sys(fregs, regs, code); +} + +/** + * denormal_to_double - Given denormalized float number, + * store double float + * + * @fpu: Pointer to sh_fpu_soft structure + * @n: Index to FP register + */ +static void denormal_to_double(struct sh_fpu_soft_struct *fpu, int n) +{ + unsigned long du, dl; + unsigned long x = fpu->fpul; + int exp = 1023 - 126; + + if (x != 0 && (x & 0x7f800000) == 0) { + du = (x & 0x80000000); + while ((x & 0x00800000) == 0) { + x <<= 1; + exp--; + } + x &= 0x007fffff; + du |= (exp << 20) | (x >> 3); + dl = x << 29; + + fpu->fp_regs[n] = du; + fpu->fp_regs[n+1] = dl; + } +} + +/** + * ieee_fpe_handler - Handle denormalized number exception + * + * @regs: Pointer to register structure + * + * Returns 1 when it's handled (should not cause exception). + */ +static int ieee_fpe_handler(struct pt_regs *regs) +{ + unsigned short insn = *(unsigned short *)regs->pc; + unsigned short finsn; + unsigned long nextpc; + siginfo_t info; + 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 */ + 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.xstate->softfpu.fpscr & (1 << 17))) { + /* FPU error */ + denormal_to_double (&tsk->thread.xstate->softfpu, + (finsn >> 8) & 0xf); + tsk->thread.xstate->softfpu.fpscr &= + ~(FPSCR_CAUSE_MASK | FPSCR_FLAG_MASK); + task_thread_info(tsk)->status |= TS_USEDFPU; + } else { + info.si_signo = SIGFPE; + info.si_errno = 0; + info.si_code = FPE_FLTINV; + info.si_addr = (void __user *)regs->pc; + force_sig_info(SIGFPE, &info, 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; + siginfo_t info; + + if (ieee_fpe_handler (®s)) + return; + + regs.pc += 2; + info.si_signo = SIGFPE; + info.si_errno = 0; + info.si_code = FPE_FLTINV; + info.si_addr = (void __user *)regs.pc; + force_sig_info(SIGFPE, &info, 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.xstate->softfpu); + + perf_sw_event(PERF_COUNT_SW_EMULATION_FAULTS, 1, regs, 0); + + if (!(task_thread_info(tsk)->status & TS_USEDFPU)) { + /* initialize once. */ + fpu_init(fpu); + task_thread_info(tsk)->status |= TS_USEDFPU; + } + + return fpu_emulate(inst, fpu, regs); +} |