2002-02-27 Greg Menke <gregory.menke@gsfc.nasa.gov>

* start/start.S: Added kseg1 test to enable cache flush code
	* bsp_specs: Added -qnostartfile to disable including bsp's start.o
	* startup/bspstart.c: Made clear_cache actually work, tweaked cpu
	init to only turn on whats needed.
	* startup/gdb-support.c: Added calls to uart 2 for gdb stub I/O and
	a handy init function.

c/src/lib/libbsp/mips/genmongoosev/startup/gdb-support.c

@@ -13,16 +13,103 @@
 
 #include <rtems.h>
 #include <rtems/bspIo.h>
+#include <libcpu/mongoose-v.h>
+
+#include <rtems/libio.h>
+
+
+
+/*
+
+We're going to call right down into the uart driver because we're
+operating within an exception.  if things are broken because something
+bad happened, this may be our last chance to debug before RTEMS goes
+mad, so we won't rely on the I/O subsystem to be operating.  This is a
+little messy, but at least we're not talking right to the hardware.
+
+*/
+
+extern int mg5uart_set_attributes(int minor,const struct termios *t);
+extern int mg5uart_open(int major,int minor, void *arg);
+extern int mg5uart_close(int major,int minor, void *arg);
+extern void mg5uart_write_polled(int minor, char c );
+extern int mg5uart_inbyte_nonblocking_polled(int minor);
+
+
+extern void mips_gdb_stub_install(void);
+
+
+static int debugUartEnabled = 0;
+
+
+
+int mg5rdbgOpenGDBuart(int breakoninit)
+{
+   struct termios t;
+   memset(&t,0,sizeof(struct termios));
+
+   if( mg5uart_open(0,1,NULL) != RTEMS_SUCCESSFUL )
+   {
+      printf("gdbstub: Failed to open UART port 2\n");
+      return -1;
+   }
+
+   t.c_cflag |= B19200;
+   t.c_cflag |= CS8;
+   if( mg5uart_set_attributes(1,&t) != 0 )
+   {
+      printf("gdbstub: Failed to configure UART 2 for 19200N82\n");
+      return -1;
+   }
+
+   debugUartEnabled  = -1;
+
+   /* set up vectoring for gdb */
+   mips_gdb_stub_install();
+
+   printf("gdbstub: Remote GDB stub listening on UART 2 at 19200N82\n");
+
+   if( breakoninit ) 
+   {
+      /* 
+         break to gdb.  We'll wait there for the operator to get their gdb
+         going, then they can 'continue' or do whatever.
+      */
+      mips_break(0);
+   }
+
+   printf("gdbstub: User code running\n");
+
+   return RTEMS_SUCCESSFUL;
+}
+
+
+void mg5rdbgCloseGDBuart(void)
+{
+   mg5uart_close(0,1,NULL);
+   debugUartEnabled  = 0;
+}
+
+
 
 
 char getDebugChar (void)
 {
-  return 0;
+   if( debugUartEnabled )
+   {
+      int rv;
+
+      while( (rv = mg5uart_inbyte_nonblocking_polled(1)) < 0 );
+      return (char)rv;
+   }
+
+   return 0;
 }
 
+
 void putDebugChar (char c)
 {
-  /* big hack */
-  printk( "%c" );
+   if( debugUartEnabled )
+      return mg5uart_write_polled(1,c);
 }