[PATCH 6/7] lib: sbi: Not use smepmp if has pmp reserved and MSECCFG.MML=1

[Yangyu Chen]

If the platform already sets any locked PMPs before OpenSBI starts,
CSR.MSECCFG.MML should never change by OpenSBI to make the locked PMPs
behave as expected.

Signed-off-by: Yangyu Chen <cyy at cyyself.name>
---
 lib/sbi/sbi_hart.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/lib/sbi/sbi_hart.c b/lib/sbi/sbi_hart.c
index f836b1c..fe24e82 100644
--- a/lib/sbi/sbi_hart.c
+++ b/lib/sbi/sbi_hart.c
@@ -559,7 +559,8 @@ int sbi_hart_pmp_configure(struct sbi_scratch *scratch)
 	pmp_bits = sbi_hart_pmp_addrbits(scratch) - 1;
 	pmp_addr_max = (1UL << pmp_bits) | ((1UL << pmp_bits) - 1);
 
-	if (sbi_hart_has_extension(scratch, SBI_HART_EXT_SMEPMP))
+	if (sbi_hart_has_extension(scratch, SBI_HART_EXT_SMEPMP) &&
+		(csr_read(CSR_MSECCFG) & MSECCFG_MML || !sbi_hart_pmp_reserved(scratch)))
 		rc = sbi_hart_smepmp_configure(scratch, pmp_count,
 						pmp_gran_log2, pmp_addr_max);
 	else
-- 
2.43.0