diff options
Diffstat (limited to 'arch/nds32/math-emu/fpuemu.c')
| -rw-r--r-- | arch/nds32/math-emu/fpuemu.c | 357 |
1 files changed, 357 insertions, 0 deletions
diff --git a/arch/nds32/math-emu/fpuemu.c b/arch/nds32/math-emu/fpuemu.c new file mode 100644 index 000000000000..75cf1643fa78 --- /dev/null +++ b/arch/nds32/math-emu/fpuemu.c @@ -0,0 +1,357 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2005-2018 Andes Technology Corporation + +#include <asm/bitfield.h> +#include <asm/uaccess.h> +#include <asm/sfp-machine.h> +#include <asm/fpuemu.h> +#include <asm/nds32_fpu_inst.h> + +#define DPFROMREG(dp, x) (dp = (void *)((unsigned long *)fpu_reg + 2*x)) +#ifdef __NDS32_EL__ +#define SPFROMREG(sp, x)\ + ((sp) = (void *)((unsigned long *)fpu_reg + (x^1))) +#else +#define SPFROMREG(sp, x) ((sp) = (void *)((unsigned long *)fpu_reg + x)) +#endif + +#define DEF3OP(name, p, f1, f2) \ +void fpemu_##name##p(void *ft, void *fa, void *fb) \ +{ \ + f1(fa, fa, fb); \ + f2(ft, ft, fa); \ +} + +#define DEF3OPNEG(name, p, f1, f2, f3) \ +void fpemu_##name##p(void *ft, void *fa, void *fb) \ +{ \ + f1(fa, fa, fb); \ + f2(ft, ft, fa); \ + f3(ft, ft); \ +} +DEF3OP(fmadd, s, fmuls, fadds); +DEF3OP(fmsub, s, fmuls, fsubs); +DEF3OP(fmadd, d, fmuld, faddd); +DEF3OP(fmsub, d, fmuld, fsubd); +DEF3OPNEG(fnmadd, s, fmuls, fadds, fnegs); +DEF3OPNEG(fnmsub, s, fmuls, fsubs, fnegs); +DEF3OPNEG(fnmadd, d, fmuld, faddd, fnegd); +DEF3OPNEG(fnmsub, d, fmuld, fsubd, fnegd); + +static const unsigned char cmptab[8] = { + SF_CEQ, + SF_CEQ, + SF_CLT, + SF_CLT, + SF_CLT | SF_CEQ, + SF_CLT | SF_CEQ, + SF_CUN, + SF_CUN +}; + +enum ARGTYPE { + S1S = 1, + S2S, + S1D, + CS, + D1D, + D2D, + D1S, + CD +}; +union func_t { + void (*t)(void *ft, void *fa, void *fb); + void (*b)(void *ft, void *fa); +}; +/* + * Emulate a single FPU arithmetic instruction. + */ +static int fpu_emu(struct fpu_struct *fpu_reg, unsigned long insn) +{ + int rfmt; /* resulting format */ + union func_t func; + int ftype = 0; + + switch (rfmt = NDS32Insn_OPCODE_COP0(insn)) { + case fs1_op:{ + switch (NDS32Insn_OPCODE_BIT69(insn)) { + case fadds_op: + func.t = fadds; + ftype = S2S; + break; + case fsubs_op: + func.t = fsubs; + ftype = S2S; + break; + case fmadds_op: + func.t = fpemu_fmadds; + ftype = S2S; + break; + case fmsubs_op: + func.t = fpemu_fmsubs; + ftype = S2S; + break; + case fnmadds_op: + func.t = fpemu_fnmadds; + ftype = S2S; + break; + case fnmsubs_op: + func.t = fpemu_fnmsubs; + ftype = S2S; + break; + case fmuls_op: + func.t = fmuls; + ftype = S2S; + break; + case fdivs_op: + func.t = fdivs; + ftype = S2S; + break; + case fs1_f2op_op: + switch (NDS32Insn_OPCODE_BIT1014(insn)) { + case fs2d_op: + func.b = fs2d; + ftype = S1D; + break; + case fsqrts_op: + func.b = fsqrts; + ftype = S1S; + break; + default: + return SIGILL; + } + break; + default: + return SIGILL; + } + break; + } + case fs2_op: + switch (NDS32Insn_OPCODE_BIT69(insn)) { + case fcmpeqs_op: + case fcmpeqs_e_op: + case fcmplts_op: + case fcmplts_e_op: + case fcmples_op: + case fcmples_e_op: + case fcmpuns_op: + case fcmpuns_e_op: + ftype = CS; + break; + default: + return SIGILL; + } + break; + case fd1_op:{ + switch (NDS32Insn_OPCODE_BIT69(insn)) { + case faddd_op: + func.t = faddd; + ftype = D2D; + break; + case fsubd_op: + func.t = fsubd; + ftype = D2D; + break; + case fmaddd_op: + func.t = fpemu_fmaddd; + ftype = D2D; + break; + case fmsubd_op: + func.t = fpemu_fmsubd; + ftype = D2D; + break; + case fnmaddd_op: + func.t = fpemu_fnmaddd; + ftype = D2D; + break; + case fnmsubd_op: + func.t = fpemu_fnmsubd; + ftype = D2D; + break; + case fmuld_op: + func.t = fmuld; + ftype = D2D; + break; + case fdivd_op: + func.t = fdivd; + ftype = D2D; + break; + case fd1_f2op_op: + switch (NDS32Insn_OPCODE_BIT1014(insn)) { + case fd2s_op: + func.b = fd2s; + ftype = D1S; + break; + case fsqrtd_op: + func.b = fsqrtd; + ftype = D1D; + break; + default: + return SIGILL; + } + break; + default: + return SIGILL; + + } + break; + } + + case fd2_op: + switch (NDS32Insn_OPCODE_BIT69(insn)) { + case fcmpeqd_op: + case fcmpeqd_e_op: + case fcmpltd_op: + case fcmpltd_e_op: + case fcmpled_op: + case fcmpled_e_op: + case fcmpund_op: + case fcmpund_e_op: + ftype = CD; + break; + default: + return SIGILL; + } + break; + + default: + return SIGILL; + } + + switch (ftype) { + case S1S:{ + void *ft, *fa; + + SPFROMREG(ft, NDS32Insn_OPCODE_Rt(insn)); + SPFROMREG(fa, NDS32Insn_OPCODE_Ra(insn)); + func.b(ft, fa); + break; + } + case S2S:{ + void *ft, *fa, *fb; + + SPFROMREG(ft, NDS32Insn_OPCODE_Rt(insn)); + SPFROMREG(fa, NDS32Insn_OPCODE_Ra(insn)); + SPFROMREG(fb, NDS32Insn_OPCODE_Rb(insn)); + func.t(ft, fa, fb); + break; + } + case S1D:{ + void *ft, *fa; + + DPFROMREG(ft, NDS32Insn_OPCODE_Rt(insn)); + SPFROMREG(fa, NDS32Insn_OPCODE_Ra(insn)); + func.b(ft, fa); + break; + } + case CS:{ + unsigned int cmpop = NDS32Insn_OPCODE_BIT69(insn); + void *ft, *fa, *fb; + + SPFROMREG(ft, NDS32Insn_OPCODE_Rt(insn)); + SPFROMREG(fa, NDS32Insn_OPCODE_Ra(insn)); + SPFROMREG(fb, NDS32Insn_OPCODE_Rb(insn)); + if (cmpop < 0x8) { + cmpop = cmptab[cmpop]; + fcmps(ft, fa, fb, cmpop); + } else + return SIGILL; + break; + } + case D1D:{ + void *ft, *fa; + + DPFROMREG(ft, NDS32Insn_OPCODE_Rt(insn)); + DPFROMREG(fa, NDS32Insn_OPCODE_Ra(insn)); + func.b(ft, fa); + break; + } + case D2D:{ + void *ft, *fa, *fb; + + DPFROMREG(ft, NDS32Insn_OPCODE_Rt(insn)); + DPFROMREG(fa, NDS32Insn_OPCODE_Ra(insn)); + DPFROMREG(fb, NDS32Insn_OPCODE_Rb(insn)); + func.t(ft, fa, fb); + break; + } + case D1S:{ + void *ft, *fa; + + SPFROMREG(ft, NDS32Insn_OPCODE_Rt(insn)); + DPFROMREG(fa, NDS32Insn_OPCODE_Ra(insn)); + func.b(ft, fa); + break; + } + case CD:{ + unsigned int cmpop = NDS32Insn_OPCODE_BIT69(insn); + void *ft, *fa, *fb; + + SPFROMREG(ft, NDS32Insn_OPCODE_Rt(insn)); + DPFROMREG(fa, NDS32Insn_OPCODE_Ra(insn)); + DPFROMREG(fb, NDS32Insn_OPCODE_Rb(insn)); + if (cmpop < 0x8) { + cmpop = cmptab[cmpop]; + fcmpd(ft, fa, fb, cmpop); + } else + return SIGILL; + break; + } + default: + return SIGILL; + } + + /* + * If an exception is required, generate a tidy SIGFPE exception. + */ +#if IS_ENABLED(CONFIG_SUPPORT_DENORMAL_ARITHMETIC) + if (((fpu_reg->fpcsr << 5) & fpu_reg->fpcsr & FPCSR_mskALLE_NO_UDFE) || + ((fpu_reg->fpcsr & FPCSR_mskUDF) && (fpu_reg->UDF_trap))) +#else + if ((fpu_reg->fpcsr << 5) & fpu_reg->fpcsr & FPCSR_mskALLE) +#endif + return SIGFPE; + return 0; +} + + +int do_fpuemu(struct pt_regs *regs, struct fpu_struct *fpu) +{ + unsigned long insn = 0, addr = regs->ipc; + unsigned long emulpc, contpc; + unsigned char *pc = (void *)&insn; + char c; + int i = 0, ret; + + for (i = 0; i < 4; i++) { + if (__get_user(c, (unsigned char *)addr++)) + return SIGBUS; + *pc++ = c; + } + + insn = be32_to_cpu(insn); + + emulpc = regs->ipc; + contpc = regs->ipc + 4; + + if (NDS32Insn_OPCODE(insn) != cop0_op) + return SIGILL; + switch (NDS32Insn_OPCODE_COP0(insn)) { + case fs1_op: + case fs2_op: + case fd1_op: + case fd2_op: + { + /* a real fpu computation instruction */ + ret = fpu_emu(fpu, insn); + if (!ret) + regs->ipc = contpc; + } + break; + + default: + return SIGILL; + } + + return ret; +} |