diff options
Diffstat (limited to 'arch/mips/math-emu/cp1emu.c')
| -rw-r--r-- | arch/mips/math-emu/cp1emu.c | 41 |
1 files changed, 27 insertions, 14 deletions
diff --git a/arch/mips/math-emu/cp1emu.c b/arch/mips/math-emu/cp1emu.c index c70f25f5889e..6fed6ce43c4e 100644 --- a/arch/mips/math-emu/cp1emu.c +++ b/arch/mips/math-emu/cp1emu.c @@ -79,7 +79,17 @@ struct mips_fpu_emulator_private fpuemuprivate; /* Convert Mips rounding mode (0..3) to IEEE library modes. */ static const unsigned char ieee_rm[4] = { - IEEE754_RN, IEEE754_RZ, IEEE754_RU, IEEE754_RD + [FPU_CSR_RN] = IEEE754_RN, + [FPU_CSR_RZ] = IEEE754_RZ, + [FPU_CSR_RU] = IEEE754_RU, + [FPU_CSR_RD] = IEEE754_RD, +}; +/* Convert IEEE library modes to Mips rounding mode (0..3). */ +static const unsigned char mips_rm[4] = { + [IEEE754_RN] = FPU_CSR_RN, + [IEEE754_RZ] = FPU_CSR_RZ, + [IEEE754_RD] = FPU_CSR_RD, + [IEEE754_RU] = FPU_CSR_RU, }; #if __mips >= 4 @@ -368,6 +378,7 @@ static int cop1Emulate(struct pt_regs *xcp, struct mips_fpu_soft_struct *ctx) } if (MIPSInst_RD(ir) == FPCREG_CSR) { value = ctx->fcr31; + value = (value & ~0x3) | mips_rm[value & 0x3]; #ifdef CSRTRACE printk("%p gpr[%d]<-csr=%08x\n", (void *) (xcp->cp0_epc), @@ -400,11 +411,10 @@ static int cop1Emulate(struct pt_regs *xcp, struct mips_fpu_soft_struct *ctx) (void *) (xcp->cp0_epc), MIPSInst_RT(ir), value); #endif - ctx->fcr31 = value; - /* copy new rounding mode and - flush bit to ieee library state! */ - ieee754_csr.nod = (ctx->fcr31 & 0x1000000) != 0; - ieee754_csr.rm = ieee_rm[value & 0x3]; + value &= (FPU_CSR_FLUSH | FPU_CSR_ALL_E | FPU_CSR_ALL_S | 0x03); + ctx->fcr31 &= ~(FPU_CSR_FLUSH | FPU_CSR_ALL_E | FPU_CSR_ALL_S | 0x03); + /* convert to ieee library modes */ + ctx->fcr31 |= (value & ~0x3) | ieee_rm[value & 0x3]; } if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) { return SIGFPE; @@ -570,7 +580,7 @@ static const unsigned char cmptab[8] = { static ieee754##p fpemu_##p##_##name (ieee754##p r, ieee754##p s, \ ieee754##p t) \ { \ - struct ieee754_csr ieee754_csr_save; \ + struct _ieee754_csr ieee754_csr_save; \ s = f1 (s, t); \ ieee754_csr_save = ieee754_csr; \ s = f2 (s, r); \ @@ -699,8 +709,6 @@ static int fpux_emu(struct pt_regs *xcp, struct mips_fpu_soft_struct *ctx, rcsr |= FPU_CSR_INV_X | FPU_CSR_INV_S; ctx->fcr31 = (ctx->fcr31 & ~FPU_CSR_ALL_X) | rcsr; - if (ieee754_csr.nod) - ctx->fcr31 |= 0x1000000; if ((ctx->fcr31 >> 5) & ctx->fcr31 & FPU_CSR_ALL_E) { /*printk ("SIGFPE: fpu csr = %08x\n", ctx->fcr31); */ @@ -1297,12 +1305,17 @@ int fpu_emulator_cop1Handler(int xcptno, struct pt_regs *xcp, if (insn == 0) xcp->cp0_epc += 4; /* skip nops */ else { - /* Update ieee754_csr. Only relevant if we have a - h/w FPU */ - ieee754_csr.nod = (ctx->fcr31 & 0x1000000) != 0; - ieee754_csr.rm = ieee_rm[ctx->fcr31 & 0x3]; - ieee754_csr.cx = (ctx->fcr31 >> 12) & 0x1f; + /* + * The 'ieee754_csr' is an alias of + * ctx->fcr31. No need to copy ctx->fcr31 to + * ieee754_csr. But ieee754_csr.rm is ieee + * library modes. (not mips rounding mode) + */ + /* convert to ieee library modes */ + ieee754_csr.rm = ieee_rm[ieee754_csr.rm]; sig = cop1Emulate(xcp, ctx); + /* revert to mips rounding mode */ + ieee754_csr.rm = mips_rm[ieee754_csr.rm]; } if (cpu_has_fpu) |