From 2ba1a053a54bc86a1c89da074d3e971dd2e8c85b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C3=89milie=20Feral?= <emilie.feral@numworks.com>
Date: Tue, 19 Mar 2019 11:56:11 +0100
Subject: [PATCH] [ion] Flash: between data write operations or accesses to
 FLASH_CR, issue a DSB instruction to guarantee the completion of the
 operation

---
 ion/src/device/shared/drivers/flash.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/ion/src/device/shared/drivers/flash.cpp b/ion/src/device/shared/drivers/flash.cpp
index 03cceac2d..7a3a0db1d 100644
--- a/ion/src/device/shared/drivers/flash.cpp
+++ b/ion/src/device/shared/drivers/flash.cpp
@@ -1,4 +1,5 @@
 #include "flash.h"
+#include <drivers/cache.h>
 #include <assert.h>
 
 namespace Ion {
@@ -8,6 +9,9 @@ namespace Flash {
 using namespace Regs;
 
 static inline void wait() {
+  /* Issue a DSB instruction to guarantee the completion of a previous access
+   * to FLASH_CR register or data write operation. (RM0431) */
+  Cache::dsb();
   // Wait for pending Flash operations to complete
   while (FLASH.SR()->getBSY()) {
   }