diff options
| -rw-r--r-- | lib/sbi/sbi_init.c | 29 |
1 files changed, 28 insertions, 1 deletions
diff --git a/lib/sbi/sbi_init.c b/lib/sbi/sbi_init.c index e1a1d96d..65d81bac 100644 --- a/lib/sbi/sbi_init.c +++ b/lib/sbi/sbi_init.c @@ -295,6 +295,7 @@ static atomic_t coldboot_lottery = ATOMIC_INITIALIZER(0); */ void __noreturn sbi_init(struct sbi_scratch *scratch) { + bool next_mode_supported = FALSE; bool coldboot = FALSE; u32 hartid = current_hartid(); const struct sbi_platform *plat = sbi_platform_ptr(scratch); @@ -303,7 +304,33 @@ void __noreturn sbi_init(struct sbi_scratch *scratch) sbi_platform_hart_invalid(plat, hartid)) sbi_hart_hang(); - if (atomic_xchg(&coldboot_lottery, 1) == 0) + switch (scratch->next_mode) { + case PRV_M: + next_mode_supported = TRUE; + break; + case PRV_S: + if (misa_extension('S')) + next_mode_supported = TRUE; + break; + case PRV_U: + if (misa_extension('U')) + next_mode_supported = TRUE; + break; + default: + sbi_hart_hang(); + } + + /* + * Only the HART supporting privilege mode specified in the + * scratch->next_mode should be allowed to become the coldboot + * HART because the coldboot HART will be directly jumping to + * the next booting stage. + * + * We use a lottery mechanism to select coldboot HART among + * HARTs which satisfy above condition. + */ + + if (next_mode_supported && atomic_xchg(&coldboot_lottery, 1) == 0) coldboot = TRUE; if (coldboot) |