Commit 6888199f authored by Ananth N Mavinakayanahalli's avatar Ananth N Mavinakayanahalli Committed by Paul Mackerras

[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: default avatarAnanth N Mavinakayanahalli <ananth@in.ibm.com>
Signed-off-by: default avatarPaul Mackerras <paulus@samba.org>
parent 5cc5133a
...@@ -54,7 +54,7 @@ static int __kprobes branch_taken(unsigned int instr, struct pt_regs *regs) ...@@ -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) 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; unsigned long int imm;
opcode = instr >> 26; opcode = instr >> 26;
...@@ -152,6 +152,49 @@ int __kprobes emulate_step(struct pt_regs *regs, unsigned int instr) ...@@ -152,6 +152,49 @@ int __kprobes emulate_step(struct pt_regs *regs, unsigned int instr)
regs->nip &= 0xffffffffUL; regs->nip &= 0xffffffffUL;
return 1; return 1;
#endif #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; return 0;
......
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