1 files changed, 135 insertions, 0 deletions
diff --git a/bsps/i386/pc386/start/bspgetworkarea.c b/bsps/i386/pc386/start/bspgetworkarea.c
new file mode 100644
index 0000000000..21cb472607
--- /dev/null
+++ b/bsps/i386/pc386/start/bspgetworkarea.c
@@ -0,0 +1,135 @@
+/*
+ *  This routine is an implementation of the bsp_work_area_initialize()
+ *  that can be used by all m68k BSPs following linkcmds conventions
+ *  regarding heap, stack, and workspace allocation.
+ *
+ *  COPYRIGHT (c) 1989-2008.
+ *  On-Line Applications Research Corporation (OAR).
+ *
+ *  The license and distribution terms for this file may be
+ *  found in the file LICENSE in this distribution or at
+ *  http://www.rtems.org/license/LICENSE.
+ */
+
+/* #define BSP_GET_WORK_AREA_DEBUG */
+#include <bsp.h>
+#include <bsp/bootcard.h>
+
+#ifdef BSP_GET_WORK_AREA_DEBUG
+  #include <rtems/bspIo.h>
+#endif
+
+/*
+ *  These are provided by the linkcmds.
+ */
+extern char   WorkAreaBase[];
+extern char   HeapSize[];
+extern char   RamSize[];
+
+/* rudimentary multiboot info */
+struct multiboot_info {
+  uint32_t  flags;       /* start.S only raises flags for items actually */
+                         /* saved; this allows us to check for the size  */
+                         /* of the data structure.                       */
+  uint32_t  mem_lower;  /* avail kB in lower memory */
+  uint32_t  mem_upper;  /* avail kB in lower memory */
+  /* ... (unimplemented) */
+};
+
+extern struct multiboot_info _boot_multiboot_info;
+
+/*
+ *  This is the first address of the memory we can use for the RTEMS
+ *  Work Area.
+ */ 
+static uintptr_t rtemsWorkAreaStart;
+
+/*
+ * Board's memory size easily be overridden by application.
+ */
+uint32_t bsp_mem_size = 0;
+
+/* Size of stack used during initialization. Defined in 'start.s'.  */
+extern uint32_t _stack_size;
+
+static void bsp_size_memory(void)
+{
+  uintptr_t topAddr;
+
+  /* Set the value of start of free memory. */
+  rtemsWorkAreaStart = (uint32_t)WorkAreaBase + _stack_size;
+
+  /* Align the RTEMS Work Area at beginning of free memory. */
+  if (rtemsWorkAreaStart & (CPU_ALIGNMENT - 1))  /* not aligned => align it */
+    rtemsWorkAreaStart = (rtemsWorkAreaStart+CPU_ALIGNMENT) & ~(CPU_ALIGNMENT-1);
+
+  /* The memory detection algorithm is very crude; try
+   * to use multiboot info, if possible (set from start.S)
+   */
+  if ( ((uintptr_t)RamSize == (uintptr_t) 0xFFFFFFFF)  &&
+       (_boot_multiboot_info.flags & 1) &&
+       _boot_multiboot_info.mem_upper ) {
+    topAddr = _boot_multiboot_info.mem_upper * 1024;
+    #ifdef BSP_GET_WORK_AREA_DEBUG
+      printk( "Multiboot info says we have 0x%08x\n", topAddr );
+    #endif
+  } else if ( (uintptr_t) RamSize == (uintptr_t) 0xFFFFFFFF ) {
+    uintptr_t lowest;
+    uint32_t  val;
+    int       i;
+
+    /*
+     * We have to dynamically size memory. Memory size can be anything
+     * between no less than 2M and 2048M.  If we can write a value to
+     * an address and read the same value back, then the memory is there.
+     *
+     * WARNING: This can detect memory which should be reserved for
+     *          graphics controllers which share the CPU's RAM.
+     */
+
+    /* find the lowest 1M boundary to probe */
+    lowest = ((rtemsWorkAreaStart + (1<<20)) >> 20) + 1;
+    if ( lowest  < 2 )
+      lowest = 2;
+
+    for (i=2048; i>=lowest; i--) {
+      topAddr = i*1024*1024 - 4;
+      *(volatile uint32_t*)topAddr = topAddr;
+    }
+
+    for(i=lowest; i<=2048; i++) {
+      topAddr = i*1024*1024 - 4;
+      val =  *(volatile uint32_t*)topAddr;
+      if (val != topAddr) {
+        break;
+      }
+    }
+
+    topAddr = (i-1)*1024*1024;
+    #ifdef BSP_GET_WORK_AREA_DEBUG
+      printk( "Dynamically sized to 0x%08x\n", topAddr );
+    #endif
+  } else {
+    topAddr = (uintptr_t) RamSize;
+    #ifdef BSP_GET_WORK_AREA_DEBUG
+      printk( "hardcoded to 0x%08x\n", topAddr );
+    #endif
+  }
+
+  bsp_mem_size = topAddr;
+}
+
+void bsp_work_area_initialize(void)
+{
+  void *area_start;
+  uintptr_t area_size;
+
+  /*
+   *  We need to determine how much memory there is in the system.
+   */
+  bsp_size_memory();
+
+  area_start = (void *) rtemsWorkAreaStart;
+  area_size  = (uintptr_t) bsp_mem_size - (uintptr_t) rtemsWorkAreaStart;
+  bsp_work_area_initialize_default( area_start, area_size );
+}