Better generation of heap section.

With this change, the heap section occupy the whole space from the end of
the bss section to the start of the stack section instead of taking a
fixed size in RAM.

This change allows applications to make a more efficient use of the RAM
available and allows application to be compiled if the space between end
of bss and start of stack is less than 2048 bytes.

hal/targets/cmsis/TARGET_NORDIC/TARGET_MCU_NRF51822/TOOLCHAIN_GCC_ARM/TARGET_MCU_NORDIC_32K/NRF51822.ld

@@ -124,18 +124,20 @@ SECTIONS
 		__bss_end__ = .;
 	} > RAM
 
-	.heap (COPY):
+	.heap (NOLOAD):
 	{
 		__end__ = .;
 		end = __end__;
+		__HeapBase = .;
 		*(.heap*)
+		. = ORIGIN(RAM) + LENGTH(RAM) - Stack_Size;
 		__HeapLimit = .;
 	} > RAM
 
 	/* .stack_dummy section doesn't contains any symbols. It is only
 	 * used for linker to calculate size of stack sections, and assign
 	 * values to stack symbols later */
-	.stack_dummy (COPY):
+	.stack_dummy (NOLOAD):
 	{
 		*(.stack*)
 	} > RAM

hal/targets/cmsis/TARGET_NORDIC/TARGET_MCU_NRF51822/TOOLCHAIN_GCC_ARM/TARGET_MCU_NRF51_16K_S110/NRF51822.ld

@@ -124,18 +124,20 @@ SECTIONS
 		__bss_end__ = .;
 	} > RAM
 
-	.heap (COPY):
+	.heap (NOLOAD):
 	{
 		__end__ = .;
 		end = __end__;
+		__HeapBase = .;
 		*(.heap*)
+		. = ORIGIN(RAM) + LENGTH(RAM) - Stack_Size;
 		__HeapLimit = .;
 	} > RAM
 
 	/* .stack_dummy section doesn't contains any symbols. It is only
 	 * used for linker to calculate size of stack sections, and assign
 	 * values to stack symbols later */
-	.stack_dummy (COPY):
+	.stack_dummy (NOLOAD):
 	{
 		*(.stack*)
 	} > RAM

hal/targets/cmsis/TARGET_NORDIC/TARGET_MCU_NRF51822/TOOLCHAIN_GCC_ARM/TARGET_MCU_NRF51_16K_S130/NRF51822.ld

@@ -124,18 +124,20 @@ SECTIONS
 		__bss_end__ = .;
 	} > RAM
 
-	.heap (COPY):
+	.heap (NOLOAD):
 	{
 		__end__ = .;
 		end = __end__;
+		__HeapBase = .;
 		*(.heap*)
+		. = ORIGIN(RAM) + LENGTH(RAM) - Stack_Size;
 		__HeapLimit = .;
 	} > RAM
 
 	/* .stack_dummy section doesn't contains any symbols. It is only
 	 * used for linker to calculate size of stack sections, and assign
 	 * values to stack symbols later */
-	.stack_dummy (COPY):
+	.stack_dummy (NOLOAD):
 	{
 		*(.stack*)
 	} > RAM

hal/targets/cmsis/TARGET_NORDIC/TARGET_MCU_NRF51822/TOOLCHAIN_GCC_ARM/startup_NRF51822.S

@@ -1,4 +1,4 @@
-/* 
+/*
 Copyright (c) 2013, Nordic Semiconductor ASA
 All rights reserved.
 
@@ -28,8 +28,8 @@ OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 
-/* 
+/*
-NOTE: Template files (including this one) are application specific and therefore 
+NOTE: Template files (including this one) are application specific and therefore
 expected to be copied into the application project folder prior to its use!
 */
 
@@ -43,6 +43,7 @@ expected to be copied into the application project folder prior to its use!
 #else
     .equ    Stack_Size, 2048
 #endif
+    .globl    Stack_Size
     .globl    __StackTop
     .globl    __StackLimit
 __StackLimit:
@@ -53,21 +54,9 @@ __StackTop:
 
     .section .heap
     .align 3
-#ifdef __HEAP_SIZE
-    .equ    Heap_Size, __HEAP_SIZE
-#else
-    .equ    Heap_Size, 2048
-#endif
     .globl    __HeapBase
     .globl    __HeapLimit
-__HeapBase:
+
-    .if    Heap_Size
-    .space    Heap_Size
-    .endif
-    .size __HeapBase, . - __HeapBase
-__HeapLimit:
-    .size __HeapLimit, . - __HeapLimit
-    
     .section .Vectors
     .align 2
     .globl __Vectors
@@ -129,7 +118,7 @@ __Vectors:
 /* Reset Handler */
 
     .equ    NRF_POWER_RAMON_ADDRESS,            0x40000524
-    .equ    NRF_POWER_RAMON_RAMxON_ONMODE_Msk,  0x3  
+    .equ    NRF_POWER_RAMON_RAMxON_ONMODE_Msk,  0x3
 
     .text
     .thumb
@@ -148,7 +137,7 @@ Reset_Handler:
     STR     R2, [R0]
 
 /*     Loop to copy data from read only memory to RAM. The ranges
- *      of copy from/to are specified by following symbols evaluated in 
+ *      of copy from/to are specified by following symbols evaluated in
  *      linker script.
  *      __etext: End of code section, i.e., begin of data sections to copy from.
  *      __data_start__/__data_end__: RAM address range that data should be
@@ -167,7 +156,7 @@ Reset_Handler:
     str    r0, [r2,r3]
     bgt    .LC1
 .LC0:
-    
+
     LDR     R0, =SystemInit
     BLX     R0
     LDR     R0, =_start
@@ -259,4 +248,3 @@ Default_Handler:
 
 
   .end
-