[PATCH RFC 08/12] RISC-V: add vector crypto extension detection

[Heiko Stuebner]

From: Heiko Stuebner <heiko.stuebner@xxxxxxxx>

Add detection for some extensions of the vector-crypto specification, namely
- Zvkb: Vector Bit-manipulation used in Cryptography
- Zvkg: Vector GCM/GMAC
- Zvknha and Zvknhb: NIST Algorithm Suite

As their use is very specific and will likely be limited to special places
we expect current code to just pre-encode those instructions, so right now
we don't introduce toolchain requirements.

Signed-off-by: Heiko Stuebner <heiko.stuebner@xxxxxxxx>
---
 arch/riscv/include/asm/hwcap.h | 4 ++++
 arch/riscv/kernel/cpu.c        | 4 ++++
 arch/riscv/kernel/cpufeature.c | 4 ++++
 3 files changed, 12 insertions(+)

diff --git a/arch/riscv/include/asm/hwcap.h b/arch/riscv/include/asm/hwcap.h
index 23427b9ed1e6..ce683dfb849f 100644
--- a/arch/riscv/include/asm/hwcap.h
+++ b/arch/riscv/include/asm/hwcap.h
@@ -64,6 +64,10 @@ enum riscv_isa_ext_id {
 	RISCV_ISA_EXT_ZBKB,
 	RISCV_ISA_EXT_ZICBOM,
 	RISCV_ISA_EXT_ZIHINTPAUSE,
+	RISCV_ISA_EXT_ZVKB,
+	RISCV_ISA_EXT_ZVKG,
+	RISCV_ISA_EXT_ZVKNHA,
+	RISCV_ISA_EXT_ZVKNHB,
 	RISCV_ISA_EXT_ID_MAX
 };
 static_assert(RISCV_ISA_EXT_ID_MAX <= RISCV_ISA_EXT_MAX);
diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
index f9f361285b04..bc615dbbf766 100644
--- a/arch/riscv/kernel/cpu.c
+++ b/arch/riscv/kernel/cpu.c
@@ -190,6 +190,10 @@ static struct riscv_isa_ext_data isa_ext_arr[] = {
 	__RISCV_ISA_EXT_DATA(zbkb, RISCV_ISA_EXT_ZBKB),
 	__RISCV_ISA_EXT_DATA(zicbom, RISCV_ISA_EXT_ZICBOM),
 	__RISCV_ISA_EXT_DATA(zihintpause, RISCV_ISA_EXT_ZIHINTPAUSE),
+	__RISCV_ISA_EXT_DATA(zvkb, RISCV_ISA_EXT_ZVKB),
+	__RISCV_ISA_EXT_DATA(zvkg, RISCV_ISA_EXT_ZVKG),
+	__RISCV_ISA_EXT_DATA(zvknha, RISCV_ISA_EXT_ZVKNHA),
+	__RISCV_ISA_EXT_DATA(zvknhb, RISCV_ISA_EXT_ZVKNHB),
 	__RISCV_ISA_EXT_DATA(sscofpmf, RISCV_ISA_EXT_SSCOFPMF),
 	__RISCV_ISA_EXT_DATA(sstc, RISCV_ISA_EXT_SSTC),
 	__RISCV_ISA_EXT_DATA(svinval, RISCV_ISA_EXT_SVINVAL),
diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
index 695dfd732483..4f08b7d97810 100644
--- a/arch/riscv/kernel/cpufeature.c
+++ b/arch/riscv/kernel/cpufeature.c
@@ -239,6 +239,10 @@ printk("!!!! isa-string: %s\n\n\n", isa);
 				SET_ISA_EXT_MAP("zbkb", RISCV_ISA_EXT_ZBKB);
 				SET_ISA_EXT_MAP("zicbom", RISCV_ISA_EXT_ZICBOM);
 				SET_ISA_EXT_MAP("zihintpause", RISCV_ISA_EXT_ZIHINTPAUSE);
+				SET_ISA_EXT_MAP("zvkb", RISCV_ISA_EXT_ZVKB);
+				SET_ISA_EXT_MAP("zvkg", RISCV_ISA_EXT_ZVKG);
+				SET_ISA_EXT_MAP("zvknha", RISCV_ISA_EXT_ZVKNHA);
+				SET_ISA_EXT_MAP("zvknhb", RISCV_ISA_EXT_ZVKNHB);
 			}
 #undef SET_ISA_EXT_MAP
 		}
-- 
2.39.0