score: Delete _Thread_BSP_context

Do not return to BSP context in the exit() shutdown path.  This makes it
possible to re-use the initialization stack.  It can be used for the
interrupt stack for example.  On targets with a small RAM this is a
considerable benefit.

This change eliminates also some special cases and simplifies the code.

Delete _Thread_Set_global_exit_status(),
_Thread_Get_global_exit_status() and _Thread_Stop_multitasking().

1 files changed, 5 insertions, 31 deletions

diff --git a/cpukit/score/cpu/arm/armv7m-multitasking-start-stop.c b/cpukit/score/cpu/arm/armv7m-multitasking-start-stop.c
index f3e96e343c..864bb53379 100644
--- a/cpukit/score/cpu/arm/armv7m-multitasking-start-stop.c
+++ b/cpukit/score/cpu/arm/armv7m-multitasking-start-stop.c
@@ -1,14 +1,14 @@
 /**
  * @file
  *
- * @brief ARMV7M Start and Stop Multitasking
+ * @brief ARMV7M Start Multitasking
  */
 
 /*
- * Copyright (c) 2011 Sebastian Huber.  All rights reserved.
+ * Copyright (c) 2011-2014 Sebastian Huber.  All rights reserved.
  *
  *  embedded brains GmbH
- *  Obere Lagerstr. 30
+ *  Dornierstr. 4
  *  82178 Puchheim
  *  Germany
  *  <rtems@embedded-brains.de>
@@ -27,18 +27,14 @@
 #ifdef ARM_MULTILIB_ARCH_V7M
 
 void __attribute__((naked)) _ARMV7M_Start_multitasking(
-  Context_Control *bsp,
   Context_Control *heir
 )
 {
   __asm__ volatile (
-    /* Store BSP context */
-    "stm r0, {r4-r11, lr}\n"
-    "str sp, [r0, %[spctxoff]]\n"
     /* Restore heir context */
-    "ldr r2, [r1, %[spctxoff]]\n"
+    "ldr r2, [r0, %[spctxoff]]\n"
     "msr psp, r2\n"
-    "ldm r1, {r4-r11, lr}\n"
+    "ldm r0, {r4-r11, lr}\n"
     /* Enable process stack pointer (PSP) */
     "mrs r2, control\n"
     "orr r2, #0x2\n"
@@ -50,26 +46,4 @@ void __attribute__((naked)) _ARMV7M_Start_multitasking(
   );
 }
 
-void __attribute__((naked)) _ARMV7M_Stop_multitasking( Context_Control *bsp )
-{
-  __asm__ volatile (
-    /* Disable interrupts */
-    "mov r2, #0x80\n"
-    "msr basepri_max, r2\n"
-    /* Restore BSP context */
-    "ldr r2, [r0, %[spctxoff]]\n"
-    "msr msp, r2\n"
-    "ldm r0, {r4-r11, lr}\n"
-    /* Disable process stack pointer (PSP) */
-    "mrs r2, control\n"
-    "bic r2, #0x2\n"
-    "msr control, r2\n"
-    /* Return to BSP */
-    "bx lr\n"
-    :
-    : [spctxoff] "J" (offsetof(Context_Control, register_sp))
-  );
-  __builtin_unreachable();
-}
-
 #endif /* ARM_MULTILIB_ARCH_V7M */