MIPS: math-emu: Add support for the MIPS R6 RINT FPU instruction

MIPS R6 introduced the following instruction:
Floating-Point Round to Integral
Scalar floating-point round to integral floating point value.

RINT.fmt: FPR[fd] = round_int(FPR[fs])
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10958/Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

arch/mips/math-emu/cp1emu.c

@@ -1791,6 +1791,18 @@ static int fpu_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
 			break;
 		}
 
+		case frint_op: {
+			union ieee754sp fs;
+
+			if (!cpu_has_mips_r6)
+				return SIGILL;
+
+			SPFROMREG(fs, MIPSInst_FS(ir));
+			rv.l = ieee754sp_tlong(fs);
+			rv.s = ieee754sp_flong(rv.l);
+			goto copcsr;
+		}
+
 		case fabs_op:
 			handler.u = ieee754sp_abs;
 			goto scopuop;
@@ -2037,6 +2049,18 @@ static int fpu_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
 			break;
 		}
 
+		case frint_op: {
+			union ieee754dp fs;
+
+			if (!cpu_has_mips_r6)
+				return SIGILL;
+
+			DPFROMREG(fs, MIPSInst_FS(ir));
+			rv.l = ieee754dp_tlong(fs);
+			rv.d = ieee754dp_flong(rv.l);
+			goto copcsr;
+		}
+
 		case fabs_op:
 			handler.u = ieee754dp_abs;
 			goto dcopuop;