[POWERPC] Emulate more instructions in software

Emulate a few more instructions in software - especially useful during
singlestepping (xmon/kprobes).

Instructions emulated with this patch are mfcr/mtcr rX, mfxer/mtxer rX,
mflr/mtlr rX, mfctr/mtctr rX and mr rA,rB.

Signed-off-by: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This commit is contained in:
Ananth N Mavinakayanahalli 2007-04-18 15:56:38 +10:00 committed by Paul Mackerras
parent 5cc5133a29
commit 6888199f7f

View File

@ -54,7 +54,7 @@ static int __kprobes branch_taken(unsigned int instr, struct pt_regs *regs)
*/
int __kprobes emulate_step(struct pt_regs *regs, unsigned int instr)
{
unsigned int opcode, rd;
unsigned int opcode, rs, rb, rd, spr;
unsigned long int imm;
opcode = instr >> 26;
@ -152,6 +152,49 @@ int __kprobes emulate_step(struct pt_regs *regs, unsigned int instr)
regs->nip &= 0xffffffffUL;
return 1;
#endif
case 0x26: /* mfcr */
regs->gpr[rd] = regs->ccr;
regs->gpr[rd] &= 0xffffffffUL;
goto mtspr_out;
case 0x2a6: /* mfspr */
spr = (instr >> 11) & 0x3ff;
switch (spr) {
case 0x20: /* mfxer */
regs->gpr[rd] = regs->xer;
regs->gpr[rd] &= 0xffffffffUL;
goto mtspr_out;
case 0x100: /* mflr */
regs->gpr[rd] = regs->link;
goto mtspr_out;
case 0x120: /* mfctr */
regs->gpr[rd] = regs->ctr;
goto mtspr_out;
}
break;
case 0x378: /* orx */
rs = (instr >> 21) & 0x1f;
rb = (instr >> 11) & 0x1f;
if (rs == rb) { /* mr */
rd = (instr >> 16) & 0x1f;
regs->gpr[rd] = regs->gpr[rs];
goto mtspr_out;
}
break;
case 0x3a6: /* mtspr */
spr = (instr >> 11) & 0x3ff;
switch (spr) {
case 0x20: /* mtxer */
regs->xer = (regs->gpr[rd] & 0xffffffffUL);
goto mtspr_out;
case 0x100: /* mtlr */
regs->link = regs->gpr[rd];
goto mtspr_out;
case 0x120: /* mtctr */
regs->ctr = regs->gpr[rd];
mtspr_out:
regs->nip += 4;
return 1;
}
}
}
return 0;