diff options
author | Qiu Wenbo <qiuwenbo@phytium.com.cn> | 2020-08-13 11:38:04 +0800 |
---|---|---|
committer | Palmer Dabbelt <palmerdabbelt@google.com> | 2020-08-14 16:28:20 -0700 |
commit | 76d4467a97bd8c4bb01e810a5129c8f96d7dcbf8 (patch) | |
tree | 84f1b82db0127e821127cb882d2a06df8d58a6f6 /arch/riscv/kernel/head.S | |
parent | dbf83817315d9ce93b3e5b1c83a167f537245bd8 (diff) | |
download | linux-76d4467a97bd8c4bb01e810a5129c8f96d7dcbf8.tar.bz2 |
riscv: Setup exception vector for nommu platform
Exception vector is missing on nommu platform and that is an issue.
This patch is tested in Sipeed Maix Bit Dev Board.
Fixes: 79b1feba5455 ("RISC-V: Setup exception vector early")
Suggested-by: Anup Patel <anup@brainfault.org>
Suggested-by: Atish Patra <atishp@atishpatra.org>
Signed-off-by: Qiu Wenbo <qiuwenbo@phytium.com.cn>
Reviewed-by: Atish Patra <atish.patra@wdc.com>
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Diffstat (limited to 'arch/riscv/kernel/head.S')
-rw-r--r-- | arch/riscv/kernel/head.S | 25 |
1 files changed, 17 insertions, 8 deletions
diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S index d0c5c316e9bb..0a4e81b8dc79 100644 --- a/arch/riscv/kernel/head.S +++ b/arch/riscv/kernel/head.S @@ -77,16 +77,10 @@ relocate: csrw CSR_SATP, a0 .align 2 1: - /* Set trap vector to exception handler */ - la a0, handle_exception + /* Set trap vector to spin forever to help debug */ + la a0, .Lsecondary_park csrw CSR_TVEC, a0 - /* - * Set sup0 scratch register to 0, indicating to exception vector that - * we are presently executing in kernel. - */ - csrw CSR_SCRATCH, zero - /* Reload the global pointer */ .option push .option norelax @@ -144,9 +138,23 @@ secondary_start_common: la a0, swapper_pg_dir call relocate #endif + call setup_trap_vector tail smp_callin #endif /* CONFIG_SMP */ +.align 2 +setup_trap_vector: + /* Set trap vector to exception handler */ + la a0, handle_exception + csrw CSR_TVEC, a0 + + /* + * Set sup0 scratch register to 0, indicating to exception vector that + * we are presently executing in kernel. + */ + csrw CSR_SCRATCH, zero + ret + .Lsecondary_park: /* We lack SMP support or have too many harts, so park this hart */ wfi @@ -240,6 +248,7 @@ clear_bss_done: call relocate #endif /* CONFIG_MMU */ + call setup_trap_vector /* Restore C environment */ la tp, init_task sw zero, TASK_TI_CPU(tp) |