From c8f312698edb11ff65480a6170108b336340febe Mon Sep 17 00:00:00 2001 From: Heiko Stuebner Date: Wed, 15 Feb 2023 13:01:29 +0100 Subject: [PATCH v4 03/12] RISC-V: add helper function to read the vector VLEN VLEN describes the length of each vector register and some instructions need specific minimal VLENs to work correctly. The vector code already includes a variable riscv_vsize that contains the value of "32 vector registers with vlenb length" that gets filled during boot. vlenb is the value contained in the CSR_VLENB register and the value represents "VLEN / 8". So add riscv_vector_vlen() to return the actual VLEN value for in-kernel users when they need to check the available VLEN. Signed-off-by: Heiko Stuebner --- arch/riscv/include/asm/vector.h | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/arch/riscv/include/asm/vector.h b/arch/riscv/include/asm/vector.h index ac2c23045eec..88cf76a2316d 100644 --- a/arch/riscv/include/asm/vector.h +++ b/arch/riscv/include/asm/vector.h @@ -232,4 +232,15 @@ static inline bool riscv_v_vstate_ctrl_user_allowed(void) { return false; } #endif /* CONFIG_RISCV_ISA_V */ +/* + * Return the implementation's vlen value. + * + * riscv_vsize contains the value of "32 vector registers with vlenb length" + * so rebuild the vlen value in bits from it. + */ +static inline int riscv_vector_vlen(void) +{ + return riscv_v_vsize / 32 * 8; +} + #endif /* ! __ASM_RISCV_VECTOR_H */ -- 2.39.2