--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/cs/services/cst/cst_stack.c	Fri May 15 01:28:16 2020 +0000
@@ -0,0 +1,163 @@
+/*******************************************************************************
+ *
+ * CST_STACK.C
+ *
+ * Tasks and HISRs stacks monitoring.
+ *
+ * (C) Texas Instruments 2000
+ *
+ ******************************************************************************/
+
+#include <stdio.h>
+#include <string.h>
+
+#include "nucleus.h"
+#include "cs_defs.h"
+#include "tc_defs.h"
+
+// The following stack sizes are defined in int.s
+#define IRQ_STACK_SIZE  128                // Number of bytes in IRQ stack
+#define FIQ_STACK_SIZE  512                // Number of bytes in FIQ stack.
+#define SYSTEM_SIZE     1024               // Define the system stack size
+
+int vsi_o_trace (char * caller, unsigned long tclass, char * text);
+int vsi_t_sleep (char * caller,	unsigned long tvalue);
+
+void CST_stack_trace()
+{
+  int jndex, count, char_count;
+  TC_TCB *head, *ptr;
+  extern CS_NODE *TCD_Created_Tasks_List;
+  extern CS_NODE *TCD_Created_HISRs_List;
+  unsigned untouched;
+  char *top_stack, *top, *bottom;
+  extern char *TCT_System_Limit;
+  char result[80];
+  char name[9];
+
+  vsi_o_trace("CST", 0x08, "Stack Info ...");
+  vsi_o_trace("CST", 0x08, "    Name  top       bottom    current   untouched");
+  vsi_o_trace("CST", 0x08, "-------------------------------------------------");
+
+  for (jndex=0; jndex<2; jndex++)
+  {
+     // make use of TCB and HCB having same structure from beginning to past stack info
+     if (jndex == 0)
+         ptr = head = (TC_TCB *)TCD_Created_Tasks_List;
+     else {
+         ptr = head = (TC_TCB *)TCD_Created_HISRs_List;
+         vsi_o_trace("CST", 0x08, "-------------------------------------------------");
+     }
+
+     count = 0;
+     do
+     {
+       untouched = 0;
+       top_stack = (char *)ptr->tc_stack_start;
+       while (*top_stack == 0xFE && top_stack <= (char *)ptr->tc_stack_end)
+       {
+         untouched++;
+         top_stack++;
+       }
+
+       // Avoid to get a spurious character when tasks names are 8 characters long
+       memcpy (name, ptr->tc_name, 8);
+       name[8] = 0;
+
+       sprintf(result, "%8s: %08x  %08x  %08x  0x%x", 
+                              name, 
+                              ptr->tc_stack_start,
+                              ptr->tc_stack_end,
+                              ptr->tc_stack_pointer,
+                              untouched);
+       vsi_o_trace("CST", 0x08, result);
+       vsi_t_sleep("",30);
+
+       ptr = (TC_TCB*) ptr->tc_created.cs_next;
+    } while (ptr != head && count++ < 50);  //count is protection from infinite loops
+  } // end of  for (jndex=0; jndex<2; jndex++)
+
+  // stack allocation algorithm from the int.s function INT_Initialize()
+  //
+  //   \          \
+  //   \----------\
+  //   \          \
+  //   \          \
+  //   \          \
+  //   \ SYSSTACK \
+  //   \          \
+  //   \          \
+  //   \          \
+  //   \----------\
+  //   \          \
+  //   \ IRQSTACK \
+  //   \          \
+  //   \----------\
+  //   \          \
+  //   \          \
+  //   \ FIQSTACK \
+  //   \          \
+  //   \          \
+  //   \----------\
+  //   \          \
+
+  untouched = 0;
+  top_stack = top = (char *)TCT_System_Limit;
+  bottom = (char *) ((unsigned)TCT_System_Limit + SYSTEM_SIZE);
+  while (*top_stack == 0xFE && top_stack <= bottom)
+  {
+     untouched++;
+     top_stack++;
+  }
+
+  // "CST" being the current active task with its related CST_Stack,
+  // the System Stack is unused (current sp_svc = System Stack Bottom)
+  sprintf(result, "SYSSTACK: %08x  %08x  %08x  0x%x", 
+                          top,
+                          bottom,
+						  bottom, // current sp_svc = System Stack Bottom
+                          untouched);
+  vsi_o_trace("CST", 0x08, "-------------------------------------------------");
+  vsi_o_trace("CST", 0x08, result);
+  vsi_t_sleep("",30);
+
+  untouched = 0;
+  top_stack = top = bottom + 4;
+  bottom = (char *) ((unsigned)bottom + IRQ_STACK_SIZE);
+  while (*top_stack == 0xFE && top_stack <= bottom)
+  {
+    untouched++;
+    top_stack++;
+  }
+
+  // Since the processor is in supervisor mode (no IRQ & no FIQ),
+  // current sp_irq = IRQ Stack bottom
+  sprintf(result, "IRQSTACK: %08x  %08x  %08x  0x%x", 
+                          top,
+                          bottom,
+						  bottom, // current sp_irq = IRQ Stack bottom
+                          untouched);
+  vsi_o_trace("CST", 0x08, result);
+  vsi_t_sleep("",30);
+
+  untouched = 0;
+  top_stack = top = bottom + 4;
+  bottom = (char *) ((unsigned)bottom + FIQ_STACK_SIZE);
+  while (*top_stack == 0xFE && top_stack <= bottom)
+  {
+    untouched++;
+    top_stack++;
+  }
+
+  // Since the processor is in supervisor mode (no IRQ & no FIQ),
+  // current sp_fiq = FIQ Stack bottom
+  sprintf(result, "FIQSTACK: %08x  %08x  %08x  0x%x", 
+                          top,
+                          bottom,
+						  bottom, // current sp_fiq = FIQ Stack bottom
+                          untouched);
+  vsi_o_trace("CST", 0x08, result);
+  vsi_o_trace("CST", 0x08, "-------------------------------------------------");
+  vsi_t_sleep("",30);
+}
+