| Message ID | 20231127070703.1697-2-jerry.shih@sifive.com (mailing list archive) |
|---|---|
| State | Superseded |
| Delegated to: | Herbert Xu |
| Headers | show |
| Series | RISC-V: provide some accelerated cryptography implementations using vector extensions | expand |
On Mon, Nov 27, 2023 at 03:06:51PM +0800, Jerry Shih wrote: > From: Heiko Stuebner <heiko.stuebner@vrull.eu> > > 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_v_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 <heiko.stuebner@vrull.eu> > Signed-off-by: Jerry Shih <jerry.shih@sifive.com> > --- > arch/riscv/include/asm/vector.h | 11 +++++++++++ > 1 file changed, 11 insertions(+) Reviewed-by: Eric Biggers <ebiggers@google.com> - Eric
diff --git a/arch/riscv/include/asm/vector.h b/arch/riscv/include/asm/vector.h index 9fb2dea66abd..1fd3e5510b64 100644 --- a/arch/riscv/include/asm/vector.h +++ b/arch/riscv/include/asm/vector.h @@ -244,4 +244,15 @@ void kernel_vector_allow_preemption(void); #define kernel_vector_allow_preemption() do {} while (0) #endif +/* + * Return the implementation's vlen value. + * + * riscv_v_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 */