MIPS: Emulate the new MIPS R6 BOVC, BEQC and BEQZALC instructions

MIPS R6 uses the <R6 ADDI opcode for the new BOVC, BEQC and
BEQZALC instructions.

Signed-off-by: Markos Chandras <markos.chandras@imgtec.com>
This commit is contained in:
Markos Chandras 2014-11-26 14:08:52 +00:00
parent 8467ca0122
commit c893ce38b2
3 changed files with 21 additions and 1 deletions

View file

@ -21,7 +21,7 @@
enum major_op {
spec_op, bcond_op, j_op, jal_op,
beq_op, bne_op, blez_op, bgtz_op,
addi_op, addiu_op, slti_op, sltiu_op,
addi_op, cbcond0_op = addi_op, addiu_op, slti_op, sltiu_op,
andi_op, ori_op, xori_op, lui_op,
cop0_op, cop1_op, cop2_op, cop1x_op,
beql_op, bnel_op, blezl_op, bgtzl_op,

View file

@ -790,6 +790,17 @@ int __compute_return_epc_for_insn(struct pt_regs *regs,
regs->cp0_epc += 8;
break;
#endif
case cbcond0_op:
/* Only valid for MIPS R6 */
if (!cpu_has_mips_r6) {
ret = -SIGILL;
break;
}
/* Compact branches: bovc, beqc, beqzalc */
if (insn.i_format.rt && !insn.i_format.rs)
regs->regs[31] = epc + 4;
regs->cp0_epc += 8;
break;
}
return ret;

View file

@ -623,6 +623,15 @@ static int isBranchInstr(struct pt_regs *regs, struct mm_decoded_insn dec_insn,
dec_insn.pc_inc +
dec_insn.next_pc_inc;
return 1;
case cbcond0_op:
if (!cpu_has_mips_r6)
break;
if (insn.i_format.rt && !insn.i_format.rs)
regs->regs[31] = regs->cp0_epc + 4;
*contpc = regs->cp0_epc + dec_insn.pc_inc +
dec_insn.next_pc_inc;
return 1;
#ifdef CONFIG_CPU_CAVIUM_OCTEON
case lwc2_op: /* This is bbit0 on Octeon */
if ((regs->regs[insn.i_format.rs] & (1ull<<insn.i_format.rt)) == 0)