This feature contains only the CHKFEAT instruction. It has
no ID enable, being back-allocated into the hint nop space.
Signed-off-by: Richard Henderson <richard.hender...@linaro.org>
---
target/arm/tcg/translate-a64.c | 14 ++++++++++++++
docs/system/arm/emulation.rst | 1 +
target/arm/tcg/a64.decode | 1 +
3 files changed, 16 insertions(+)
diff --git a/target/arm/tcg/translate-a64.c b/target/arm/tcg/translate-a64.c
index 7831b3dab3..34d22cac8a 100644
--- a/target/arm/tcg/translate-a64.c
+++ b/target/arm/tcg/translate-a64.c
@@ -2124,6 +2124,20 @@ static bool trans_AUTIBSP(DisasContext *s, arg_AUTIBSP
*a)
return true;
}
+static bool trans_CHKFEAT(DisasContext *s, arg_CHKFEAT *a)
+{
+ uint64_t feat_en = 0;
+
+ if (s->gcs_en) {
+ feat_en |= 1 << 0;
+ }
+ if (feat_en) {
+ TCGv_i64 x16 = cpu_reg(s, 16);
+ tcg_gen_andi_i64(x16, x16, ~feat_en);
+ }
+ return true;
+}
+
static bool trans_CLREX(DisasContext *s, arg_CLREX *a)
{
tcg_gen_movi_i64(cpu_exclusive_addr, -1);
diff --git a/docs/system/arm/emulation.rst b/docs/system/arm/emulation.rst
index 6ebf9c9ce9..b894aced89 100644
--- a/docs/system/arm/emulation.rst
+++ b/docs/system/arm/emulation.rst
@@ -28,6 +28,7 @@ the following architecture extensions:
- FEAT_BF16 (AArch64 BFloat16 instructions)
- FEAT_BTI (Branch Target Identification)
- FEAT_CCIDX (Extended cache index)
+- FEAT_CHK (Check Feature Status)
- FEAT_CMOW (Control for cache maintenance permission)
- FEAT_CRC32 (CRC32 instructions)
- FEAT_Crypto (Cryptographic Extension)
diff --git a/target/arm/tcg/a64.decode b/target/arm/tcg/a64.decode
index 8c798cde2b..4315ed8dab 100644
--- a/target/arm/tcg/a64.decode
+++ b/target/arm/tcg/a64.decode
@@ -246,6 +246,7 @@ ERETA 1101011 0100 11111 00001 m:1 11111 11111
&reta # ERETAA, ERETAB
AUTIASP 1101 0101 0000 0011 0010 0011 101 11111
AUTIBZ 1101 0101 0000 0011 0010 0011 110 11111
AUTIBSP 1101 0101 0000 0011 0010 0011 111 11111
+ CHKFEAT 1101 0101 0000 0011 0010 0101 000 11111
]
# The canonical NOP has CRm == op2 == 0, but all of the space
# that isn't specifically allocated to an instruction must NOP
--
2.43.0
