linux_dsm_epyc7002/arch/mips/include/asm/branch.h
Leonid Yegoshin b0a668fb20 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>
2015-02-17 15:37:37 +00:00

104 lines
2.4 KiB
C

/*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 1996, 1997, 1998, 2001 by Ralf Baechle
*/
#ifndef _ASM_BRANCH_H
#define _ASM_BRANCH_H
#include <asm/cpu-features.h>
#include <asm/mipsregs.h>
#include <asm/ptrace.h>
#include <asm/inst.h>
extern int __isa_exception_epc(struct pt_regs *regs);
extern int __compute_return_epc(struct pt_regs *regs);
extern int __compute_return_epc_for_insn(struct pt_regs *regs,
union mips_instruction insn);
extern int __microMIPS_compute_return_epc(struct pt_regs *regs);
extern int __MIPS16e_compute_return_epc(struct pt_regs *regs);
/*
* microMIPS bitfields
*/
#define MM_POOL32A_MINOR_MASK 0x3f
#define MM_POOL32A_MINOR_SHIFT 0x6
#define MM_MIPS32_COND_FC 0x30
extern int __mm_isBranchInstr(struct pt_regs *regs,
struct mm_decoded_insn dec_insn, unsigned long *contpc);
static inline int mm_isBranchInstr(struct pt_regs *regs,
struct mm_decoded_insn dec_insn, unsigned long *contpc)
{
if (!cpu_has_mmips)
return 0;
return __mm_isBranchInstr(regs, dec_insn, contpc);
}
static inline int delay_slot(struct pt_regs *regs)
{
return regs->cp0_cause & CAUSEF_BD;
}
static inline void clear_delay_slot(struct pt_regs *regs)
{
regs->cp0_cause &= ~CAUSEF_BD;
}
static inline void set_delay_slot(struct pt_regs *regs)
{
regs->cp0_cause |= CAUSEF_BD;
}
static inline unsigned long exception_epc(struct pt_regs *regs)
{
if (likely(!delay_slot(regs)))
return regs->cp0_epc;
if (get_isa16_mode(regs->cp0_epc))
return __isa_exception_epc(regs);
return regs->cp0_epc + 4;
}
#define BRANCH_LIKELY_TAKEN 0x0001
static inline int compute_return_epc(struct pt_regs *regs)
{
if (get_isa16_mode(regs->cp0_epc)) {
if (cpu_has_mmips)
return __microMIPS_compute_return_epc(regs);
if (cpu_has_mips16)
return __MIPS16e_compute_return_epc(regs);
return regs->cp0_epc;
}
if (!delay_slot(regs)) {
regs->cp0_epc += 4;
return 0;
}
return __compute_return_epc(regs);
}
static inline int MIPS16e_compute_return_epc(struct pt_regs *regs,
union mips16e_instruction *inst)
{
if (likely(!delay_slot(regs))) {
if (inst->ri.opcode == MIPS16e_extend_op) {
regs->cp0_epc += 4;
return 0;
}
regs->cp0_epc += 2;
return 0;
}
return __MIPS16e_compute_return_epc(regs);
}
#endif /* _ASM_BRANCH_H */