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

MIPS R6 introduced the following instruction:
SELNEZ.fmt: FPR[fd]  FPR[ft].bit0 ? FPR[fs] : 0

Add support for emulating the single and double precision
formats of the said instruction.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
Cc: linux-mips@linux-mips.org
Patchwork: https://patchwork.linux-mips.org/patch/10955/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>

1 files changed, 22 insertions, 0 deletions

diff --git a/arch/mips/math-emu/cp1emu.c b/arch/mips/math-emu/cp1emu.c
index 02ba536f1594..8978d52adf0e 100644
--- a/arch/mips/math-emu/cp1emu.c
+++ b/arch/mips/math-emu/cp1emu.c
@@ -1754,6 +1754,17 @@ static int fpu_emu(struct pt_regs *xcp, struct mips_fpu_struct *ctx,
                                 SPFROMREG(rv.s, MIPSInst_FS(ir));
                         break;
 
+                case fselnez_op:
+                        if (!cpu_has_mips_r6)
+                                return SIGILL;
+
+                        SPFROMREG(rv.s, MIPSInst_FT(ir));
+                        if (rv.w & 0x1)
+                                SPFROMREG(rv.s, MIPSInst_FS(ir));
+                        else
+                                rv.w = 0;
+                        break;
+
                 case fabs_op:
                         handler.u = ieee754sp_abs;
                         goto scopuop;
@@ -1963,6 +1974,17 @@ copcsr:
                                 DPFROMREG(rv.d, MIPSInst_FS(ir));
                         break;
 
+                case fselnez_op:
+                        if (!cpu_has_mips_r6)
+                                return SIGILL;
+
+                        DPFROMREG(rv.d, MIPSInst_FT(ir));
+                        if (rv.l & 0x1)
+                                DPFROMREG(rv.d, MIPSInst_FS(ir));
+                        else
+                                rv.l = 0;
+                        break;
+
                 case fabs_op:
                         handler.u = ieee754dp_abs;
                         goto dcopuop;