diff options
| author | Greentime Hu <greentime.hu@sifive.com> | 2023-06-05 11:07:02 +0000 |
|---|---|---|
| committer | Palmer Dabbelt <palmer@rivosinc.com> | 2023-06-08 07:16:38 -0700 |
| commit | 6b533828726af4e3609aeb6e5f494e936f9a7cde (patch) | |
| tree | ac7db3b9596667f60776d14b34152c8a4c4e765a /arch/riscv/kernel/head.S | |
| parent | b5665d2a94325c3244584f504d039a573cfd63e8 (diff) | |
riscv: Clear vector regfile on bootup
clear vector registers on boot if kernel supports V.
Signed-off-by: Greentime Hu <greentime.hu@sifive.com>
Signed-off-by: Vineet Gupta <vineetg@rivosinc.com>
Signed-off-by: Andy Chiu <andy.chiu@sifive.com>
Acked-by: Conor Dooley <conor.dooley@microchip.com>
Reviewed-by: Heiko Stuebner <heiko.stuebner@vrull.eu>
Tested-by: Heiko Stuebner <heiko.stuebner@vrull.eu>
Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com>
Link: https://lore.kernel.org/r/20230605110724.21391-6-andy.chiu@sifive.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Diffstat (limited to 'arch/riscv/kernel/head.S')
| -rw-r--r-- | arch/riscv/kernel/head.S | 27 |
1 files changed, 25 insertions, 2 deletions
diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S index 4bf6c449d78b..3fd6a4bd9c3e 100644 --- a/arch/riscv/kernel/head.S +++ b/arch/riscv/kernel/head.S @@ -392,7 +392,7 @@ ENTRY(reset_regs) #ifdef CONFIG_FPU csrr t0, CSR_MISA andi t0, t0, (COMPAT_HWCAP_ISA_F | COMPAT_HWCAP_ISA_D) - beqz t0, .Lreset_regs_done + beqz t0, .Lreset_regs_done_fpu li t1, SR_FS csrs CSR_STATUS, t1 @@ -430,8 +430,31 @@ ENTRY(reset_regs) fmv.s.x f31, zero csrw fcsr, 0 /* note that the caller must clear SR_FS */ +.Lreset_regs_done_fpu: #endif /* CONFIG_FPU */ -.Lreset_regs_done: + +#ifdef CONFIG_RISCV_ISA_V + csrr t0, CSR_MISA + li t1, COMPAT_HWCAP_ISA_V + and t0, t0, t1 + beqz t0, .Lreset_regs_done_vector + + /* + * Clear vector registers and reset vcsr + * VLMAX has a defined value, VLEN is a constant, + * and this form of vsetvli is defined to set vl to VLMAX. + */ + li t1, SR_VS + csrs CSR_STATUS, t1 + csrs CSR_VCSR, x0 + vsetvli t1, x0, e8, m8, ta, ma + vmv.v.i v0, 0 + vmv.v.i v8, 0 + vmv.v.i v16, 0 + vmv.v.i v24, 0 + /* note that the caller must clear SR_VS */ +.Lreset_regs_done_vector: +#endif /* CONFIG_RISCV_ISA_V */ ret END(reset_regs) #endif /* CONFIG_RISCV_M_MODE */ |