diff --git a/lib/utils/timer/aclint_mtimer.c b/lib/utils/timer/aclint_mtimer.c
index 271e6252..9acb26eb 100644
--- a/lib/utils/timer/aclint_mtimer.c
+++ b/lib/utils/timer/aclint_mtimer.c
@@ -72,14 +72,10 @@ static u64 mtimer_value(void)
 static void mtimer_event_stop(void)
 {
 	u32 target_hart = current_hartid();
-	struct sbi_scratch *scratch;
+	struct sbi_scratch *scratch = sbi_scratch_thishart_ptr();
 	struct aclint_mtimer_data *mt;
 	u64 *time_cmp;
 
-	scratch = sbi_hartid_to_scratch(target_hart);
-	if (!scratch)
-		return;
-
 	mt = mtimer_get_hart_data_ptr(scratch);
 	if (!mt)
 		return;
@@ -92,14 +88,10 @@ static void mtimer_event_stop(void)
 static void mtimer_event_start(u64 next_event)
 {
 	u32 target_hart = current_hartid();
-	struct sbi_scratch *scratch;
+	struct sbi_scratch *scratch = sbi_scratch_thishart_ptr();
 	struct aclint_mtimer_data *mt;
 	u64 *time_cmp;
 
-	scratch = sbi_hartid_to_scratch(target_hart);
-	if (!scratch)
-		return;
-
 	mt = mtimer_get_hart_data_ptr(scratch);
 	if (!mt)
 		return;
@@ -155,13 +147,9 @@ int aclint_mtimer_warm_init(void)
 {
 	u64 *mt_time_cmp;
 	u32 target_hart = current_hartid();
-	struct sbi_scratch *scratch;
+	struct sbi_scratch *scratch = sbi_scratch_thishart_ptr();
 	struct aclint_mtimer_data *mt;
 
-	scratch = sbi_hartid_to_scratch(target_hart);
-	if (!scratch)
-		return SBI_ENOENT;
-
 	mt = mtimer_get_hart_data_ptr(scratch);
 	if (!mt)
 		return SBI_ENODEV;