From 830d8084b0a32956b59fe694b1ed5fc48226818c Mon Sep 17 00:00:00 2001
From: Markus Koch <markus@notsyncing.net>
Date: Fri, 2 Aug 2024 16:40:56 +0200
Subject: [PATCH] Update to Zephyr 3.7.0

---
 west.yml                                |  2 +-
 zephyr/soc/riscv/servant/CMakeLists.txt |  1 +
 zephyr/soc/riscv/servant/cpu_idle.c     | 22 ++++++++++++++++++++++
 3 files changed, 24 insertions(+), 1 deletion(-)
 create mode 100644 zephyr/soc/riscv/servant/cpu_idle.c

diff --git a/west.yml b/west.yml
index 1f14b1a..cc4c437 100644
--- a/west.yml
+++ b/west.yml
@@ -5,5 +5,5 @@ manifest:
   projects:
     - name: zephyr
       remote: zephyrproject-rtos
-      revision: v3.5.0
+      revision: v3.7.0
       import: true
diff --git a/zephyr/soc/riscv/servant/CMakeLists.txt b/zephyr/soc/riscv/servant/CMakeLists.txt
index ffe3a45..aee4e42 100644
--- a/zephyr/soc/riscv/servant/CMakeLists.txt
+++ b/zephyr/soc/riscv/servant/CMakeLists.txt
@@ -4,4 +4,5 @@
 zephyr_sources(
     soc_irq.S
     vector.S
+    cpu_idle.c
     irq.c)
diff --git a/zephyr/soc/riscv/servant/cpu_idle.c b/zephyr/soc/riscv/servant/cpu_idle.c
new file mode 100644
index 0000000..dc318c6
--- /dev/null
+++ b/zephyr/soc/riscv/servant/cpu_idle.c
@@ -0,0 +1,22 @@
+#include <zephyr/irq.h>
+#include <zephyr/tracing/tracing.h>
+
+// Override arch_cpu_idle() and arch_cpu_atomic_idle() to prevent insertion
+// of `wfi` instructions, which lock up our system. This was introduced in
+// Zephyr 3.6.0 with commit 5fb6e267f629dedb8382da6bcad8018b1bb8930a.
+//
+// This is probably a hardware bug in SERV. This issue is tracked as #131.
+// https://github.com/olofk/serv/issues/131
+
+void arch_cpu_idle(void)
+{
+	sys_trace_idle();
+	irq_unlock(MSTATUS_IEN);
+}
+
+void arch_cpu_atomic_idle(unsigned int key)
+{
+	sys_trace_idle();
+	irq_unlock(key);
+}
+