From b0a668fb2038d846a466c7a16a358d874002b697 Mon Sep 17 00:00:00 2001
From: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Date: Wed, 3 Dec 2014 15:47:03 +0000
Subject: MIPS: kernel: mips-r2-to-r6-emul: Add R2 emulator for MIPS R6

MIPS R6 removed quite a few R2 instructions. However, there
is plenty of <R6 userland code so we add an in-kernel emulator
so we can still be able to execute all R2 userland out there.

The emulator comes with a handy debugfs under /mips/ directory
(r2-emul-stats) to provide some basic statistics of the
instructions that are being emulated.

Below are some statistics from booting a minimal buildroot image:

Instruction     Total   BDslot
------------------------------
movs            236969  0
hilo            56686   0
muls            55279   0
divs            10941   0
dsps            0       0
bops            1       0
traps           0       0
fpus            0       0
loads           214981  17
stores          103364  0
llsc            56898   0
dsemul          150418  0
jr              370158
bltzl           43
bgezl           1594
bltzll          0
bgezll          0
bltzal          39
bgezal          39
beql            14503
bnel            138741
blezl           0
bgtzl           3988

Signed-off-by: Leonid Yegoshin <Leonid.Yegoshin@imgtec.com>
Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
---
 arch/mips/math-emu/cp1emu.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

(limited to 'arch/mips/math-emu')

diff --git a/arch/mips/math-emu/cp1emu.c b/arch/mips/math-emu/cp1emu.c
index 6e7920b20822..3c341b08d120 100644
--- a/arch/mips/math-emu/cp1emu.c
+++ b/arch/mips/math-emu/cp1emu.c
@@ -48,6 +48,7 @@
 #include <asm/processor.h>
 #include <asm/fpu_emulator.h>
 #include <asm/fpu.h>
+#include <asm/mips-r2-to-r6-emul.h>
 
 #include "ieee754.h"
 
@@ -68,7 +69,7 @@ static int fpux_emu(struct pt_regs *,
 #define modeindex(v) ((v) & FPU_CSR_RM)
 
 /* convert condition code register number to csr bit */
-static const unsigned int fpucondbit[8] = {
+const unsigned int fpucondbit[8] = {
 	FPU_CSR_COND0,
 	FPU_CSR_COND1,
 	FPU_CSR_COND2,
-- 
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