Export Zacas ISA extension through hwprobe.
Signed-off-by: Clément Léger <cleger@xxxxxxxxxxxx>
---
Documentation/arch/riscv/hwprobe.rst | 4 ++++
arch/riscv/include/uapi/asm/hwprobe.h | 1 +
arch/riscv/kernel/sys_riscv.c | 1 +
3 files changed, 6 insertions(+)
diff --git a/Documentation/arch/riscv/hwprobe.rst b/Documentation/arch/riscv/hwprobe.rst
index 10bd7b170118..bff68004ad43 100644
--- a/Documentation/arch/riscv/hwprobe.rst
+++ b/Documentation/arch/riscv/hwprobe.rst
@@ -165,6 +165,10 @@ The following keys are defined:
defined in the RISC-V ISA manual starting from commit 5618fb5a216b
("Ztso is now ratified.")
+ * :c:macro:`RISCV_HWPROBE_EXT_ZACAS`: The Zacas extension is supported as
+ defined in the Atomic Compare-and-Swap (CAS) instructions manual starting
+ from commit 5059e0ca641c ("update to ratified").
+
* :c:macro:`RISCV_HWPROBE_KEY_CPUPERF_0`: A bitmask that contains performance
information about the selected set of processors.
diff --git a/arch/riscv/include/uapi/asm/hwprobe.h b/arch/riscv/include/uapi/asm/hwprobe.h
index 01ac3dc196e5..ac65bb43c8e7 100644
--- a/arch/riscv/include/uapi/asm/hwprobe.h
+++ b/arch/riscv/include/uapi/asm/hwprobe.h
@@ -57,6 +57,7 @@ struct riscv_hwprobe {
#define RISCV_HWPROBE_EXT_ZVFHMIN (1 << 31)
#define RISCV_HWPROBE_EXT_ZFA (1ULL << 32)
#define RISCV_HWPROBE_EXT_ZTSO (1ULL << 33)
+#define RISCV_HWPROBE_EXT_ZACAS (1ULL << 34)
#define RISCV_HWPROBE_KEY_CPUPERF_0 5
#define RISCV_HWPROBE_MISALIGNED_UNKNOWN (0 << 0)
#define RISCV_HWPROBE_MISALIGNED_EMULATED (1 << 0)
diff --git a/arch/riscv/kernel/sys_riscv.c b/arch/riscv/kernel/sys_riscv.c
index 6564fa9e7a7f..6c680c75ac0d 100644
--- a/arch/riscv/kernel/sys_riscv.c
+++ b/arch/riscv/kernel/sys_riscv.c
@@ -175,6 +175,7 @@ static void hwprobe_isa_ext0(struct riscv_hwprobe *pair,
EXT_KEY(ZKT);
EXT_KEY(ZIHINTNTL);
EXT_KEY(ZTSO);
+ EXT_KEY(ZACAS);
if (has_vector()) {
EXT_KEY(ZVBB);
--
2.43.0
