pc386: Add BSP_ENABLE_COM1_COM4 BSP option

This allows the support for the legacy COM1-COM4 serial ports
to be completely disabled. It is needed to prevent hangs on some
hardware. In particular, the Intel Edison where it is not present.

3 files changed, 38 insertions, 27 deletions

diff --git a/c/src/lib/libbsp/i386/pc386/configure.ac b/c/src/lib/libbsp/i386/pc386/configure.ac
index 96812c8b70..9c039c927c 100644
--- a/c/src/lib/libbsp/i386/pc386/configure.ac
+++ b/c/src/lib/libbsp/i386/pc386/configure.ac
@@ -22,6 +22,11 @@ RTEMS_BSPOPTS_HELP([BSP_ENABLE_VGA],
 [Set if the VGA and keyboard console support is enabled.])
 AM_CONDITIONAL(RTEMS_VGA,[test "$BSP_ENABLE_VGA" = "1"])
 
+RTEMS_BSPOPTS_SET([BSP_ENABLE_COM1_COM4],[*],[1])
+RTEMS_BSPOPTS_HELP([BSP_ENABLE_COM1_COM4],
+[Set if COM1..COM4 support is enabled.])
+AM_CONDITIONAL(RTEMS_VGA,[test "$BSP_ENABLE_COM1_COM4" = "1"])
+
 RTEMS_BSPOPTS_SET([BSP_ENABLE_IDE],[*],[1])
 RTEMS_BSPOPTS_HELP([BSP_ENABLE_IDE],
 [Set if IDE support is enabled.])
diff --git a/c/src/lib/libbsp/i386/pc386/console/conscfg.c b/c/src/lib/libbsp/i386/pc386/console/conscfg.c
index 72ccfe3709..a34f0e5217 100644
--- a/c/src/lib/libbsp/i386/pc386/console/conscfg.c
+++ b/c/src/lib/libbsp/i386/pc386/console/conscfg.c
@@ -29,34 +29,36 @@
 #define VGA_CONSOLE_FUNCTIONS  &vgacons_fns
 #endif
 
-#if 0
-#define COM_CONSOLE_FUNCTIONS  &ns16550_fns_polled
-#else
-#define COM_CONSOLE_FUNCTIONS  &ns16550_fns
-#endif
+#if BSP_ENABLE_COM1_COM4
+  #if 0
+  #define COM_CONSOLE_FUNCTIONS  &ns16550_fns_polled
+  #else
+  #define COM_CONSOLE_FUNCTIONS  &ns16550_fns
+  #endif
 
-/*
- * Base IO for UART
- */
-#define COM1_BASE_IO  0x3F8
-#define COM2_BASE_IO  0x3E8
-#define COM3_BASE_IO  0x2F8
-#define COM4_BASE_IO  0x2E8
+  /*
+   * Base IO for UART
+   */
+  #define COM1_BASE_IO  0x3F8
+  #define COM2_BASE_IO  0x3E8
+  #define COM3_BASE_IO  0x2F8
+  #define COM4_BASE_IO  0x2E8
 
-#define CLOCK_RATE     (115200 * 16)
+  #define CLOCK_RATE     (115200 * 16)
 
-static uint8_t com_get_register(uint32_t addr, uint8_t i)
-{
-  register uint8_t val;
+  static uint8_t com_get_register(uint32_t addr, uint8_t i)
+  {
+    register uint8_t val;
   
-  inport_byte( (addr + i),val );
-  return val;
-}
+    inport_byte( (addr + i),val );
+    return val;
+  }
 
-static void com_set_register(uint32_t addr, uint8_t i, uint8_t val)
-{
-  outport_byte( (addr + i),val );
-}
+  static void com_set_register(uint32_t addr, uint8_t i, uint8_t val)
+  {
+    outport_byte( (addr + i),val );
+  }
+#endif
 
 console_tbl     Console_Configuration_Ports[] = {
 #if BSP_ENABLE_VGA
@@ -80,6 +82,7 @@ console_tbl     Console_Configuration_Ports[] = {
     0x0                                     /* ulIntVector -- base for port */
   },
 #endif
+#if BSP_ENABLE_COM1_COM4
   {
     "/dev/com1",                           /* sDeviceName */
     SERIAL_NS16550,                        /* deviceType */
@@ -158,6 +161,7 @@ console_tbl     Console_Configuration_Ports[] = {
     CLOCK_RATE,                            /* ulClock */
     BSP_UART_COM4_IRQ                      /* ulIntVector -- base for port */
   },
+#endif
 
 };
 
diff --git a/c/src/lib/libbsp/i386/pc386/console/printk_support.c b/c/src/lib/libbsp/i386/pc386/console/printk_support.c
index b34e3e9f79..c6b0fe5c00 100644
--- a/c/src/lib/libbsp/i386/pc386/console/printk_support.c
+++ b/c/src/lib/libbsp/i386/pc386/console/printk_support.c
@@ -29,9 +29,9 @@
 
 rtems_device_minor_number         BSPPrintkPort = 0;
 
-int ns16550_inbyte_nonblocking_polled(
-  int minor
-);
+#if BSP_ENABLE_COM1_COM4
+int ns16550_inbyte_nonblocking_polled( int minor );
+#endif
 
 void BSP_outch(char ch);
 int BSP_inch(void);
@@ -52,18 +52,20 @@ void BSP_outch(char ch)
 
 int BSP_inch(void) 
 {
-  int           result;
+  int           result = -1;
 
   #if BSP_ENABLE_VGA
     if ( BSPPrintkPort == BSP_CONSOLE_VGA ) {
       result = BSP_wait_polled_input();
     } else
   #endif
+  #if BSP_ENABLE_COM1_COM4
     {
       do {
         result = ns16550_inbyte_nonblocking_polled( BSPPrintkPort );
       } while (result == -1);
     }
+  #endif
   return result;
 }