diff --git a/lib/sbi_hart.c b/lib/sbi_hart.c index b30250b3..12c5c55b 100644 --- a/lib/sbi_hart.c +++ b/lib/sbi_hart.c @@ -77,17 +77,19 @@ static int fp_init(u32 hartid) static int delegate_traps(u32 hartid) { - /* send S-mode interrupts and most exceptions straight to S-mode */ - unsigned long interrupts = MIP_SSIP | MIP_STIP | MIP_SEIP; - unsigned long exceptions = (1U << CAUSE_MISALIGNED_FETCH) | - (1U << CAUSE_FETCH_PAGE_FAULT) | - (1U << CAUSE_BREAKPOINT) | - (1U << CAUSE_LOAD_PAGE_FAULT) | - (1U << CAUSE_STORE_PAGE_FAULT) | - (1U << CAUSE_USER_ECALL); + unsigned long interrupts, exceptions; - if (!misa_extension('S')) - return 0; + if (!misa_extension('S')) { + /* No delegation possible */ + interrupts = 0; + exceptions = 0; + } else { + /* Send M-mode interrupts and most exceptions to S-mode */ + interrupts = MIP_SSIP | MIP_STIP | MIP_SEIP; + exceptions = (1U << CAUSE_MISALIGNED_FETCH) | + (1U << CAUSE_BREAKPOINT) | + (1U << CAUSE_USER_ECALL); + } csr_write(mideleg, interrupts); csr_write(medeleg, exceptions);