diff options
Diffstat (limited to 'arch/mips/kernel/traps.c')
| -rw-r--r-- | arch/mips/kernel/traps.c | 47 |
1 files changed, 47 insertions, 0 deletions
diff --git a/arch/mips/kernel/traps.c b/arch/mips/kernel/traps.c index 22b19c275044..165c275163b8 100644 --- a/arch/mips/kernel/traps.c +++ b/arch/mips/kernel/traps.c @@ -724,6 +724,50 @@ int process_fpemu_return(int sig, void __user *fault_addr) } } +static int simulate_fp(struct pt_regs *regs, unsigned int opcode, + unsigned long old_epc, unsigned long old_ra) +{ + union mips_instruction inst = { .word = opcode }; + void __user *fault_addr = NULL; + int sig; + + /* If it's obviously not an FP instruction, skip it */ + switch (inst.i_format.opcode) { + case cop1_op: + case cop1x_op: + case lwc1_op: + case ldc1_op: + case swc1_op: + case sdc1_op: + break; + + default: + return -1; + } + + /* + * do_ri skipped over the instruction via compute_return_epc, undo + * that for the FPU emulator. + */ + regs->cp0_epc = old_epc; + regs->regs[31] = old_ra; + + /* Save the FP context to struct thread_struct */ + lose_fpu(1); + + /* Run the emulator */ + sig = fpu_emulator_cop1Handler(regs, ¤t->thread.fpu, 1, + &fault_addr); + + /* If something went wrong, signal */ + process_fpemu_return(sig, fault_addr); + + /* Restore the hardware register state */ + own_fpu(1); + + return 0; +} + /* * XXX Delayed fp exceptions when doing a lazy ctx switch XXX */ @@ -1016,6 +1060,9 @@ asmlinkage void do_ri(struct pt_regs *regs) if (status < 0) status = simulate_sync(regs, opcode); + + if (status < 0) + status = simulate_fp(regs, opcode, old_epc, old31); } if (status < 0) |