[PATCH v4 1/7] RISC-V: Detect Smstateen extension

[Mayuresh Chitale]

Extend the ISA string parsing to detect the Smstateen extension. If the
extension is enabled then access to certain 'state' such as AIA CSRs in
VS mode is controlled by *stateen0 registers.

Signed-off-by: Mayuresh Chitale <mchitale at ventanamicro.com>
Reviewed-by: Andrew Jones <ajones at ventanamicro.com>
---
 arch/riscv/include/asm/hwcap.h | 1 +
 arch/riscv/kernel/cpu.c        | 1 +
 arch/riscv/kernel/cpufeature.c | 1 +
 3 files changed, 3 insertions(+)

diff --git a/arch/riscv/include/asm/hwcap.h b/arch/riscv/include/asm/hwcap.h
index f041bfa7f6a0..fad1fd1fcd05 100644
--- a/arch/riscv/include/asm/hwcap.h
+++ b/arch/riscv/include/asm/hwcap.h
@@ -53,6 +53,7 @@
 #define RISCV_ISA_EXT_ZICSR		40
 #define RISCV_ISA_EXT_ZIFENCEI		41
 #define RISCV_ISA_EXT_ZIHPM		42
+#define RISCV_ISA_EXT_SMSTATEEN		43
 
 #define RISCV_ISA_EXT_MAX		64
 #define RISCV_ISA_EXT_NAME_LEN_MAX	32
diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
index a2fc952318e9..fb0df651bc48 100644
--- a/arch/riscv/kernel/cpu.c
+++ b/arch/riscv/kernel/cpu.c
@@ -217,6 +217,7 @@ static struct riscv_isa_ext_data isa_ext_arr[] = {
 	__RISCV_ISA_EXT_DATA(zbb, RISCV_ISA_EXT_ZBB),
 	__RISCV_ISA_EXT_DATA(zbs, RISCV_ISA_EXT_ZBS),
 	__RISCV_ISA_EXT_DATA(smaia, RISCV_ISA_EXT_SMAIA),
+	__RISCV_ISA_EXT_DATA(smstateen, RISCV_ISA_EXT_SMSTATEEN),
 	__RISCV_ISA_EXT_DATA(ssaia, RISCV_ISA_EXT_SSAIA),
 	__RISCV_ISA_EXT_DATA(sscofpmf, RISCV_ISA_EXT_SSCOFPMF),
 	__RISCV_ISA_EXT_DATA(sstc, RISCV_ISA_EXT_SSTC),
diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
index a8f66c015229..c3742a765f8b 100644
--- a/arch/riscv/kernel/cpufeature.c
+++ b/arch/riscv/kernel/cpufeature.c
@@ -301,6 +301,7 @@ void __init riscv_fill_hwcap(void)
 			} else {
 				/* sorted alphabetically */
 				SET_ISA_EXT_MAP("smaia", RISCV_ISA_EXT_SMAIA);
+				SET_ISA_EXT_MAP("smstateen", RISCV_ISA_EXT_SMSTATEEN);
 				SET_ISA_EXT_MAP("ssaia", RISCV_ISA_EXT_SSAIA);
 				SET_ISA_EXT_MAP("sscofpmf", RISCV_ISA_EXT_SSCOFPMF);
 				SET_ISA_EXT_MAP("sstc", RISCV_ISA_EXT_SSTC);
-- 
2.34.1