From 46e4a207af4059c1274f11bea865a7473b816923 Mon Sep 17 00:00:00 2001
From: gdisirio <gdisirio@35acf78f-673a-0410-8e92-d51de3d6d3f4>
Date: Sat, 25 Sep 2010 05:53:16 +0000
Subject: [PATCH] Fixed bug 3064274.

git-svn-id: svn://svn.code.sf.net/p/chibios/svn/branches/stable_2.0.x@2190 35acf78f-673a-0410-8e92-d51de3d6d3f4
---
 os/ports/GCC/ARMCMx/old/chcore_v7m.h | 26 ++++++++++++++++----------
 readme.txt                           |  2 ++
 2 files changed, 18 insertions(+), 10 deletions(-)

diff --git a/os/ports/GCC/ARMCMx/old/chcore_v7m.h b/os/ports/GCC/ARMCMx/old/chcore_v7m.h
index 4d225985e..d5e3995af 100644
--- a/os/ports/GCC/ARMCMx/old/chcore_v7m.h
+++ b/os/ports/GCC/ARMCMx/old/chcore_v7m.h
@@ -270,17 +270,23 @@ struct intctx {
  * @param[in] ntp       the thread to be switched in
  * @param[in] otp       the thread to be switched out
  */
-static INLINE void port_switch(Thread *ntp, Thread *otp) {
-  register Thread *_ntp asm ("r0") = (ntp);
-  register Thread *_otp asm ("r1") = (otp);
-#if CH_DBG_ENABLE_STACK_CHECK
-  register char *sp asm ("sp");
-  if (sp - sizeof(struct intctx) - sizeof(Thread) < (char *)_otp)
-    asm volatile ("movs    r0, #0                               \n\t"
-                  "b       chDbgPanic");
-#endif /* CH_DBG_ENABLE_STACK_CHECK */
-  asm volatile ("svc     #0" : : "r" (_otp), "r" (_ntp) : "memory");
+#if !CH_DBG_ENABLE_STACK_CHECK || defined(__DOXYGEN__)
+#define port_switch(ntp, otp) {                                             \
+  register Thread *_ntp asm ("r0") = (ntp);                                 \
+  register Thread *_otp asm ("r1") = (otp);                                 \
+  asm volatile ("svc     #0" : : "r" (_otp), "r" (_ntp) : "memory");        \
 }
+#else /* CH_DBG_ENABLE_STACK_CHECK */
+#define port_switch(ntp, otp) {                                             \
+  register Thread *_ntp asm ("r0") = (ntp);                                 \
+  register Thread *_otp asm ("r1") = (otp);                                 \
+  register struct intctx *r13 asm ("r13");                                  \
+  if ((void *)(r13 - 1) < (void *)(_otp + 1))                               \
+    asm volatile ("movs    r0, #0                               \n\t"       \
+                  "b       chDbgPanic");                                    \
+  asm volatile ("svc     #0" : : "r" (_otp), "r" (_ntp) : "memory");        \
+}
+#endif /* CH_DBG_ENABLE_STACK_CHECK */
 
 #ifdef __cplusplus
 extern "C" {
diff --git a/readme.txt b/readme.txt
index a39e77a4a..b2fd4935a 100644
--- a/readme.txt
+++ b/readme.txt
@@ -59,6 +59,8 @@
 *****************************************************************************
 
 *** 2.0.5 ***
+- FIX: Fixed broken CH_DBG_ENABLE_STACK_CHECK option in legacy CM3 port (bug
+  3064274).
 - FIX: Fixed CAN_USE_SLEEP_MODE setting (bug 3064204).
 
 *** 2.0.4 ***