From: Guo Ren <[email protected]> Reset vector registers at boot-time and disable vector instructions execution for kernel mode.
[[email protected]: add comments] Signed-off-by: Greentime Hu <[email protected]> Signed-off-by: Guo Ren <[email protected]> --- arch/riscv/kernel/entry.S | 6 ++--- arch/riscv/kernel/head.S | 49 +++++++++++++++++++++++++++++++++++++-- 2 files changed, 50 insertions(+), 5 deletions(-) diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S index 524d918f3601..c905efb6c998 100644 --- a/arch/riscv/kernel/entry.S +++ b/arch/riscv/kernel/entry.S @@ -67,10 +67,10 @@ _save_context: * Disable user-mode memory access as it should only be set in the * actual user copy routines. * - * Disable the FPU to detect illegal usage of floating point in kernel - * space. + * Disable the FPU/Vector to detect illegal usage of floating point + * or vector in kernel space. */ - li t0, SR_SUM | SR_FS + li t0, SR_SUM | SR_FS | SR_VS REG_L s0, TASK_TI_USER_SP(tp) csrrc s1, CSR_STATUS, t0 diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S index 0a4e81b8dc79..e97c7915ae27 100644 --- a/arch/riscv/kernel/head.S +++ b/arch/riscv/kernel/head.S @@ -204,10 +204,10 @@ pmp_done: .option pop /* - * Disable FPU to detect illegal usage of + * Disable FPU & VECTOR to detect illegal usage of * floating point in kernel space */ - li t0, SR_FS + li t0, SR_FS | SR_VS csrc CSR_STATUS, t0 #ifdef CONFIG_SMP @@ -365,6 +365,51 @@ ENTRY(reset_regs) csrw fcsr, 0 /* note that the caller must clear SR_FS */ #endif /* CONFIG_FPU */ + +#ifdef CONFIG_VECTOR + csrr t0, CSR_MISA + li t1, (COMPAT_HWCAP_ISA_V >> 16) + slli t1, t1, 16 + and t0, t0, t1 + beqz t0, .Lreset_regs_done + + li t1, SR_VS + csrs CSR_STATUS, t1 + vmv.v.i v0, 0 + vmv.v.i v1, 0 + vmv.v.i v2, 0 + vmv.v.i v3, 0 + vmv.v.i v4, 0 + vmv.v.i v5, 0 + vmv.v.i v6, 0 + vmv.v.i v7, 0 + vmv.v.i v8, 0 + vmv.v.i v9, 0 + vmv.v.i v10, 0 + vmv.v.i v11, 0 + vmv.v.i v12, 0 + vmv.v.i v13, 0 + vmv.v.i v14, 0 + vmv.v.i v15, 0 + vmv.v.i v16, 0 + vmv.v.i v17, 0 + vmv.v.i v18, 0 + vmv.v.i v19, 0 + vmv.v.i v20, 0 + vmv.v.i v21, 0 + vmv.v.i v22, 0 + vmv.v.i v23, 0 + vmv.v.i v24, 0 + vmv.v.i v25, 0 + vmv.v.i v26, 0 + vmv.v.i v27, 0 + vmv.v.i v28, 0 + vmv.v.i v29, 0 + vmv.v.i v30, 0 + vmv.v.i v31, 0 + /* note that the caller must clear SR_VS */ +#endif /* CONFIG_VECTOR */ + .Lreset_regs_done: ret END(reset_regs) -- 2.28.0
