powerpc: Emulate icbi, mcrf and conditional-trap instructions
This extends the instruction emulation done by analyse_instr() and
emulate_step() to handle a few more instructions that are found in
the kernel.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
diff --git a/arch/powerpc/include/asm/sstep.h b/arch/powerpc/include/asm/sstep.h
index 1a693b1..d3a42cc 100644
--- a/arch/powerpc/include/asm/sstep.h
+++ b/arch/powerpc/include/asm/sstep.h
@@ -66,6 +66,7 @@
#define DCBF 0x100
#define DCBTST 0x200
#define DCBT 0x300
+#define ICBI 0x400
/* Size field in type word */
#define SIZE(n) ((n) << 8)
diff --git a/arch/powerpc/lib/sstep.c b/arch/powerpc/lib/sstep.c
index 3726a03..209a506 100644
--- a/arch/powerpc/lib/sstep.c
+++ b/arch/powerpc/lib/sstep.c
@@ -600,6 +600,23 @@
regs->ccr = (regs->ccr & ~(0xf << shift)) | (crval << shift);
}
+static int __kprobes trap_compare(long v1, long v2)
+{
+ int ret = 0;
+
+ if (v1 < v2)
+ ret |= 0x10;
+ else if (v1 > v2)
+ ret |= 0x08;
+ else
+ ret |= 0x04;
+ if ((unsigned long)v1 < (unsigned long)v2)
+ ret |= 0x02;
+ else if ((unsigned long)v1 > (unsigned long)v2)
+ ret |= 0x01;
+ return ret;
+}
+
/*
* Elements of 32-bit rotate and mask instructions.
*/
@@ -669,6 +686,13 @@
return 1;
case 19:
switch ((instr >> 1) & 0x3ff) {
+ case 0: /* mcrf */
+ rd = (instr >> 21) & 0x1c;
+ ra = (instr >> 16) & 0x1c;
+ val = (regs->ccr >> ra) & 0xf;
+ regs->ccr = (regs->ccr & ~(0xfUL << rd)) | (val << rd);
+ goto instr_done;
+
case 16: /* bclr */
case 528: /* bcctr */
op->type = BRANCH;
@@ -745,6 +769,17 @@
rb = (instr >> 11) & 0x1f;
switch (opcode) {
+#ifdef __powerpc64__
+ case 2: /* tdi */
+ if (rd & trap_compare(regs->gpr[ra], (short) instr))
+ goto trap;
+ goto instr_done;
+#endif
+ case 3: /* twi */
+ if (rd & trap_compare((int)regs->gpr[ra], (short) instr))
+ goto trap;
+ goto instr_done;
+
case 7: /* mulli */
regs->gpr[rd] = regs->gpr[ra] * (short) instr;
goto instr_done;
@@ -893,6 +928,18 @@
case 31:
switch ((instr >> 1) & 0x3ff) {
+ case 4: /* tw */
+ if (rd == 0x1f ||
+ (rd & trap_compare((int)regs->gpr[ra],
+ (int)regs->gpr[rb])))
+ goto trap;
+ goto instr_done;
+#ifdef __powerpc64__
+ case 68: /* td */
+ if (rd & trap_compare(regs->gpr[ra], regs->gpr[rb]))
+ goto trap;
+ goto instr_done;
+#endif
case 83: /* mfmsr */
if (regs->msr & MSR_PR)
goto priv;
@@ -1269,6 +1316,11 @@
op->ea = xform_ea(instr, regs);
op->reg = rd;
return 0;
+
+ case 982: /* icbi */
+ op->type = MKOP(CACHEOP, ICBI, 0);
+ op->ea = xform_ea(instr, regs);
+ return 0;
}
break;
}
@@ -1597,6 +1649,11 @@
op->val = SRR1_PROGPRIV;
return 0;
+ trap:
+ op->type = INTERRUPT | 0x700;
+ op->val = SRR1_PROGTRAP;
+ return 0;
+
#ifdef CONFIG_PPC_FPU
fpunavail:
op->type = INTERRUPT | 0x800;
@@ -1714,6 +1771,9 @@
if (op.reg == 0)
prefetch((void *) op.ea);
break;
+ case ICBI:
+ __cacheop_user_asmx(op.ea, err, "icbi");
+ break;
}
if (err)
return 0;