[PATCH] lib: sbi: Refine the settings for switching to Virtual Supervisor Mode.

Pope B.Lei popeblei at gmail.com
Tue Apr 9 02:23:04 PDT 2024


Although Mstatus.MPV is set, before executing mret, access to VS mode
registers should use the actual register addresses, not the pseudonyms
of S registers.

Signed-off-by: Pope B.Lei <popeblei at gmail.com>
---
V1 -> V2: Simplify the if condition
- 
 lib/sbi/sbi_hart.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/lib/sbi/sbi_hart.c b/lib/sbi/sbi_hart.c
index 3d13694..ccdd12f 100644
--- a/lib/sbi/sbi_hart.c
+++ b/lib/sbi/sbi_hart.c
@@ -1041,10 +1041,17 @@ sbi_hart_switch_mode(unsigned long arg0, unsigned long arg1,
 	csr_write(CSR_MEPC, next_addr);
 
 	if (next_mode == PRV_S) {
-		csr_write(CSR_STVEC, next_addr);
-		csr_write(CSR_SSCRATCH, 0);
-		csr_write(CSR_SIE, 0);
-		csr_write(CSR_SATP, 0);
+		if (next_virt) {
+		    csr_write(CSR_VSTVEC, next_addr);
+		    csr_write(CSR_VSSCRATCH, 0);
+		    csr_write(CSR_VSIE, 0);
+		    csr_write(CSR_VSATP, 0);
+		} else {
+		    csr_write(CSR_STVEC, next_addr);
+		    csr_write(CSR_SSCRATCH, 0);
+		    csr_write(CSR_SIE, 0);
+		    csr_write(CSR_SATP, 0);
+		}
 	} else if (next_mode == PRV_U) {
 		if (misa_extension('N')) {
 			csr_write(CSR_UTVEC, next_addr);
-- 
2.35.2.windows.1




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