[PATCH v4 6/9] riscv: hwprobe: add zve Vector subextensions into hwprobe interface

[Andy Chiu <andy.chiu@sifive.com>]

The following Vector subextensions for "embedded" platforms are added
into RISCV_HWPROBE_KEY_IMA_EXT_0:
 - ZVE32X
 - ZVE32F
 - ZVE64X
 - ZVE64F
 - ZVE64D

Extensions ending with an X indicates that the platform doesn't have a
vector FPU.
Extensions ending with F/D mean that whether single (F) or double (D)
precision vector operation is supported.
The number 32 or 64 follows from ZVE tells the maximum element length.

Signed-off-by: Andy Chiu <andy.chiu@sifive.com>
Reviewed-by: Clément Léger <cleger@rivosinc.com>
---
Changelog v2:
 - zve* extensions in hwprobe depends on whether kernel supports v, so
   include them after has_vector(). Fix a typo. (Clément)
---
 Documentation/arch/riscv/hwprobe.rst  | 15 +++++++++++++++
 arch/riscv/include/uapi/asm/hwprobe.h |  5 +++++
 arch/riscv/kernel/sys_hwprobe.c       |  5 +++++
 3 files changed, 25 insertions(+)

diff --git a/Documentation/arch/riscv/hwprobe.rst b/Documentation/arch/riscv/hwprobe.rst
index b2bcc9eed9aa..d0b02e012e5d 100644
--- a/Documentation/arch/riscv/hwprobe.rst
+++ b/Documentation/arch/riscv/hwprobe.rst
@@ -188,6 +188,21 @@ The following keys are defined:
        manual starting from commit 95cf1f9 ("Add changes requested by Ved
        during signoff")
 
+  * :c:macro:`RISCV_HWPROBE_EXT_ZVE32X`: The Vector sub-extension Zve32x is
+    supported, as defined by version 1.0 of the RISC-V Vector extension manual.
+
+  * :c:macro:`RISCV_HWPROBE_EXT_ZVE32F`: The Vector sub-extension Zve32f is
+    supported, as defined by version 1.0 of the RISC-V Vector extension manual.
+
+  * :c:macro:`RISCV_HWPROBE_EXT_ZVE64X`: The Vector sub-extension Zve64x is
+    supported, as defined by version 1.0 of the RISC-V Vector extension manual.
+
+  * :c:macro:`RISCV_HWPROBE_EXT_ZVE64F`: The Vector sub-extension Zve64f is
+    supported, as defined by version 1.0 of the RISC-V Vector extension manual.
+
+  * :c:macro:`RISCV_HWPROBE_EXT_ZVE64D`: The Vector sub-extension Zve64d is
+    supported, as defined by version 1.0 of the RISC-V Vector extension manual.
+
 * :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 9f2a8e3ff204..b9a0876e969f 100644
--- a/arch/riscv/include/uapi/asm/hwprobe.h
+++ b/arch/riscv/include/uapi/asm/hwprobe.h
@@ -59,6 +59,11 @@ struct riscv_hwprobe {
 #define		RISCV_HWPROBE_EXT_ZTSO		(1ULL << 33)
 #define		RISCV_HWPROBE_EXT_ZACAS		(1ULL << 34)
 #define		RISCV_HWPROBE_EXT_ZICOND	(1ULL << 35)
+#define		RISCV_HWPROBE_EXT_ZVE32X	(1ULL << 36)
+#define		RISCV_HWPROBE_EXT_ZVE32F	(1ULL << 37)
+#define		RISCV_HWPROBE_EXT_ZVE64X	(1ULL << 38)
+#define		RISCV_HWPROBE_EXT_ZVE64F	(1ULL << 39)
+#define		RISCV_HWPROBE_EXT_ZVE64D	(1ULL << 40)
 #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_hwprobe.c b/arch/riscv/kernel/sys_hwprobe.c
index 8cae41a502dd..c8219b82fbfc 100644
--- a/arch/riscv/kernel/sys_hwprobe.c
+++ b/arch/riscv/kernel/sys_hwprobe.c
@@ -113,6 +113,11 @@ static void hwprobe_isa_ext0(struct riscv_hwprobe *pair,
 		EXT_KEY(ZICOND);
 
 		if (has_vector()) {
+			EXT_KEY(ZVE32X);
+			EXT_KEY(ZVE32F);
+			EXT_KEY(ZVE64X);
+			EXT_KEY(ZVE64F);
+			EXT_KEY(ZVE64D);
 			EXT_KEY(ZVBB);
 			EXT_KEY(ZVBC);
 			EXT_KEY(ZVKB);

-- 
2.44.0.rc2