From: Ravi Bangoria <ravi.bango...@linux.vnet.ibm.com>
darn: Deliver A Random Number
Currently return invalid random number for all the case. This needs
proper algorithm to provide cryptographically suitable random data.
Reading from /dev/random can block and that is not an expected behaviour
while the cpu instruction is getting executed. Moreover, /dev/random
would only work for linux-user
Signed-off-by: Ravi Bangoria <ravi.bango...@linux.vnet.ibm.com>
Signed-off-by: Nikunj A Dadhania <nik...@linux.vnet.ibm.com>
---
target-ppc/helper.h | 2 ++
target-ppc/int_helper.c | 16 ++++++++++++++++
target-ppc/translate.c | 18 ++++++++++++++++++
3 files changed, 36 insertions(+)
diff --git a/target-ppc/helper.h b/target-ppc/helper.h
index dcf3f95..695a2db 100644
--- a/target-ppc/helper.h
+++ b/target-ppc/helper.h
@@ -50,6 +50,8 @@ DEF_HELPER_FLAGS_1(cnttzd, TCG_CALL_NO_RWG_SE, tl, tl)
DEF_HELPER_FLAGS_1(popcntd, TCG_CALL_NO_RWG_SE, tl, tl)
DEF_HELPER_FLAGS_2(bpermd, TCG_CALL_NO_RWG_SE, i64, i64, i64)
DEF_HELPER_3(srad, tl, env, tl, tl)
+DEF_HELPER_0(darn32, tl)
+DEF_HELPER_0(darn64, tl)
#endif
DEF_HELPER_FLAGS_1(cntlsw32, TCG_CALL_NO_RWG_SE, i32, i32)
diff --git a/target-ppc/int_helper.c b/target-ppc/int_helper.c
index 552b2e0..ca33add 100644
--- a/target-ppc/int_helper.c
+++ b/target-ppc/int_helper.c
@@ -182,6 +182,22 @@ target_ulong helper_cnttzd(target_ulong t)
{
return ctz64(t);
}
+
+/* Return invalid random number.
+ *
+ * FIXME: Add rng backend or other mechanism to get cryptographically suitable
+ * random number
+ */
+target_ulong helper_darn32(void)
+{
+ return -1;
+}
+
+target_ulong helper_darn64(void)
+{
+ return -1;
+}
+
#endif
#if defined(TARGET_PPC64)
diff --git a/target-ppc/translate.c b/target-ppc/translate.c
index 89a4b37..2e5116e 100644
--- a/target-ppc/translate.c
+++ b/target-ppc/translate.c
@@ -526,6 +526,8 @@ EXTRACT_HELPER(FPW, 16, 1);
/* addpcis */
EXTRACT_HELPER_DXFORM(DX, 10, 6, 6, 5, 16, 1, 1, 0, 0)
+/* darn */
+EXTRACT_HELPER(L, 16, 2);
/*** Jump target decoding ***/
/* Immediate address */
@@ -1893,6 +1895,21 @@ static void gen_cnttzd(DisasContext *ctx)
gen_set_Rc0(ctx, cpu_gpr[rA(ctx->opcode)]);
}
}
+
+/* darn */
+static void gen_darn(DisasContext *ctx)
+{
+ int l = L(ctx->opcode);
+
+ if (l == 0) {
+ gen_helper_darn32(cpu_gpr[rD(ctx->opcode)]);
+ } else if (l <= 2) {
+ /* Return 64-bit random for both CRN and RRN */
+ gen_helper_darn64(cpu_gpr[rD(ctx->opcode)]);
+ } else {
+ tcg_gen_movi_i64(cpu_gpr[rD(ctx->opcode)], -1);
+ }
+}
#endif
/*** Integer rotate ***/
@@ -6207,6 +6224,7 @@ GEN_HANDLER_E(prtyw, 0x1F, 0x1A, 0x04, 0x0000F801,
PPC_NONE, PPC2_ISA205),
GEN_HANDLER(popcntd, 0x1F, 0x1A, 0x0F, 0x0000F801, PPC_POPCNTWD),
GEN_HANDLER(cntlzd, 0x1F, 0x1A, 0x01, 0x00000000, PPC_64B),
GEN_HANDLER_E(cnttzd, 0x1F, 0x1A, 0x11, 0x00000000, PPC_NONE, PPC2_ISA300),
+GEN_HANDLER_E(darn, 0x1F, 0x13, 0x17, 0x001CF801, PPC_NONE, PPC2_ISA300),
GEN_HANDLER_E(prtyd, 0x1F, 0x1A, 0x05, 0x0000F801, PPC_NONE, PPC2_ISA205),
GEN_HANDLER_E(bpermd, 0x1F, 0x1C, 0x07, 0x00000001, PPC_NONE,
PPC2_PERM_ISA206),
#endif
--
2.7.4
