score: Work area initialization API change

The work areas (RTEMS work space and C program heap) will be initialized
now in a separate step and are no longer part of
rtems_initialize_data_structures().  Initialization is performed with
tables of Heap_Area entries.  This allows usage of scattered memory
areas present on various small scale micro-controllers.

The sbrk() support API changes also.  The bsp_sbrk_init() must now deal
with a minimum size for the first memory chunk to take the configured
work space size into account.

1 files changed, 30 insertions, 0 deletions

diff --git a/cpukit/score/include/rtems/score/heap.h b/cpukit/score/include/rtems/score/heap.h
index 964386a36f..36ef48f3b6 100644
--- a/cpukit/score/include/rtems/score/heap.h
+++ b/cpukit/score/include/rtems/score/heap.h
@@ -675,6 +675,36 @@ Heap_Resize_status _Heap_Resize_block(
   uintptr_t *new_size
 );
 
+RTEMS_INLINE_ROUTINE uintptr_t _Heap_Align_up(
+  uintptr_t value,
+  uintptr_t alignment
+)
+{
+  uintptr_t remainder = value % alignment;
+
+  if ( remainder != 0 ) {
+    return value - remainder + alignment;
+  } else {
+    return value;
+  }
+}
+
+/**
+ * @brief Returns the worst case overhead to manage a memory area.
+ */
+RTEMS_INLINE_ROUTINE uintptr_t _Heap_Area_overhead(
+  uintptr_t page_size
+)
+{
+  if ( page_size != 0 ) {
+    page_size = _Heap_Align_up( page_size, CPU_ALIGNMENT );
+  } else {
+    page_size = CPU_ALIGNMENT;
+  }
+
+  return 2 * (page_size - 1) + HEAP_BLOCK_HEADER_SIZE;
+}
+
 #if !defined(__RTEMS_APPLICATION__)
 
 #include <rtems/score/heap.inl>