From 925f08e0b9c46dd3b34f0b073abf233de1820986 Mon Sep 17 00:00:00 2001
From: Eyck Jentzsch <eyck@minres.com>
Date: Sun, 14 Dec 2025 17:12:42 +0100
Subject: [PATCH] implements halt using WFI if hartid!=0 and multicore

---
 env/riscv_vp/init.c | 5 ++++-
 env/start.S         | 5 ++++-
 2 files changed, 8 insertions(+), 2 deletions(-)

diff --git a/env/riscv_vp/init.c b/env/riscv_vp/init.c
index dc60394..447a4f6 100644
--- a/env/riscv_vp/init.c
+++ b/env/riscv_vp/init.c
@@ -103,7 +103,10 @@ void __attribute__((weak)) _init() {
     while(i < NUM_INTERRUPTS) {
         localISR[i++] = default_handler;
     }
-
+#endif
+#if defined(NUM_HARTS) && NUM_HARTS > 1
+    for(int i = 1; i < NUM_HARTS; ++i)
+        set_aclint_msip(aclint, i, 1);
 #endif
 }
 
diff --git a/env/start.S b/env/start.S
index 3f83220..e6849ca 100644
--- a/env/start.S
+++ b/env/start.S
@@ -30,11 +30,14 @@ _start:
 2:
     la t0, trap_entry
     csrw mtvec, t0
-#ifdef HARTX_WAIT4WFI
+#if defined(NUM_HARTS) && NUM_HARTS>1
 	/* block other cores until hart 0 has finished initialization */
 	csrr  t0, mhartid 
 	beqz t0, hart0_init
+	/* enable MSI locally */
+	csrwi mie, 0x8 
 	wfi
+	csrw mie, zero
 	j hartx_start
 hart0_init:
 #endif