[ipxe-devel] [PATCH] [serial] Don't enable serial console without serial support

[Shao Miller]

With proper formatting for the 'if', this time...  - Shao

 From 6c5b1c214f8d94fdf9e9b56d0b7cd9de2702c214 Mon Sep 17 00:00:00 2001
From: Shao Miller <sha0.miller at gmail.com>
Date: Wed, 3 Oct 2012 14:56:13 -0400
Subject: [PATCH] [serial] Don't enable serial console without serial support

serial_console_init() would enable serial console support without
knowing if the serial driver succeeded or not.  As a result, the
serial console would interfere with a normal keyboard on a system
lacking serial support.

Steps to reproduce the problem after #defining CONSOLE_SERIAL:

   qemu -serial none -kernel bin/ipxe.lkrn -append shell

(Only the enter key would work from the keyboard)

Reported-by: Jan ONDREJ (SAL) <ondrejj(at)salstar.sk>
Signed-off-by: Shao Miller <sha0.miller at gmail.com>
---
  src/core/serial.c         | 7 ++++++-
  src/core/serial_console.c | 9 ++++++---
  src/include/ipxe/serial.h | 1 +
  3 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/src/core/serial.c b/src/core/serial.c
index a5551b1..8f5a159 100644
--- a/src/core/serial.c
+++ b/src/core/serial.c
@@ -93,6 +93,9 @@ FILE_LICENCE ( GPL2_OR_LATER );
  #define uart_writeb(val,addr) outb((val),(addr))
  #endif

+/* Boolean for the state of serial driver initialization */
+int serial_initialized = 0;
+
  /*
   * void serial_putc(int ch);
   *    Write character `ch' to port UART_BASE.
@@ -207,7 +210,6 @@ static void serial_init ( void ) {
      /* Set clear to send, so flow control works... */
      uart_writeb((1<<1), UART_BASE + UART_MCR);

-
      /* Flush the input buffer. */
      do {
          /* rx buffer reg
@@ -217,6 +219,9 @@ static void serial_init ( void ) {
          /* line status reg */
          status = uart_readb(UART_BASE + UART_LSR);
      } while(status & UART_LSR_DR);
+
+    /* Note that serial support has been initialized */
+    serial_initialized = 1;
   out:
      return;
  }
diff --git a/src/core/serial_console.c b/src/core/serial_console.c
index bbddd6b..a901915 100644
--- a/src/core/serial_console.c
+++ b/src/core/serial_console.c
@@ -18,9 +18,12 @@
  struct console_driver serial_console __console_driver;

  static void serial_console_init ( void ) {
-    /* Serial driver initialization should already be done,
-     * time to enable the serial console. */
-    serial_console.disabled = 0;
+    /*
+     * Check if serial driver initialization is done.
+     * If so, it's time to enable the serial console.
+     */
+    if (serial_initialized)
+        serial_console.disabled = 0;
  }

  struct console_driver serial_console __console_driver = {
diff --git a/src/include/ipxe/serial.h b/src/include/ipxe/serial.h
index c16e56a..b47b1d1 100644
--- a/src/include/ipxe/serial.h
+++ b/src/include/ipxe/serial.h
@@ -12,5 +12,6 @@ FILE_LICENCE ( GPL2_OR_LATER );
  extern void serial_putc ( int ch );
  extern int serial_getc ( void );
  extern int serial_ischar ( void );
+extern int serial_initialized;

  #endif /* _IPXE_SERIAL_H */
-- 
1.7.11.4

-------------- next part --------------
>From 6c5b1c214f8d94fdf9e9b56d0b7cd9de2702c214 Mon Sep 17 00:00:00 2001
From: Shao Miller <sha0.miller at gmail.com>
Date: Wed, 3 Oct 2012 14:56:13 -0400
Subject: [PATCH] [serial] Don't enable serial console without serial support

serial_console_init() would enable serial console support without
knowing if the serial driver succeeded or not.  As a result, the
serial console would interfere with a normal keyboard on a system
lacking serial support.

Steps to reproduce the problem after #defining CONSOLE_SERIAL:

  qemu -serial none -kernel bin/ipxe.lkrn -append shell

(Only the enter key would work from the keyboard)

Reported-by: Jan ONDREJ (SAL) <ondrejj(at)salstar.sk>
Signed-off-by: Shao Miller <sha0.miller at gmail.com>
---
 src/core/serial.c         | 7 ++++++-
 src/core/serial_console.c | 9 ++++++---
 src/include/ipxe/serial.h | 1 +
 3 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/src/core/serial.c b/src/core/serial.c
index a5551b1..8f5a159 100644
--- a/src/core/serial.c
+++ b/src/core/serial.c
@@ -93,6 +93,9 @@ FILE_LICENCE ( GPL2_OR_LATER );
 #define uart_writeb(val,addr) outb((val),(addr))
 #endif
 
+/* Boolean for the state of serial driver initialization */
+int serial_initialized = 0;
+
 /*
  * void serial_putc(int ch);
  *	Write character `ch' to port UART_BASE.
@@ -207,7 +210,6 @@ static void serial_init ( void ) {
 	/* Set clear to send, so flow control works... */
 	uart_writeb((1<<1), UART_BASE + UART_MCR);
 
-
 	/* Flush the input buffer. */
 	do {
 		/* rx buffer reg
@@ -217,6 +219,9 @@ static void serial_init ( void ) {
 		/* line status reg */
 		status = uart_readb(UART_BASE + UART_LSR);
 	} while(status & UART_LSR_DR);
+
+	/* Note that serial support has been initialized */
+	serial_initialized = 1;
  out:
 	return;
 }
diff --git a/src/core/serial_console.c b/src/core/serial_console.c
index bbddd6b..a901915 100644
--- a/src/core/serial_console.c
+++ b/src/core/serial_console.c
@@ -18,9 +18,12 @@
 struct console_driver serial_console __console_driver;
 
 static void serial_console_init ( void ) {
-	/* Serial driver initialization should already be done,
-	 * time to enable the serial console. */
-	serial_console.disabled = 0;
+	/*
+	 * Check if serial driver initialization is done.
+	 * If so, it's time to enable the serial console.
+	 */
+	if (serial_initialized)
+		serial_console.disabled = 0;
 }
 
 struct console_driver serial_console __console_driver = {
diff --git a/src/include/ipxe/serial.h b/src/include/ipxe/serial.h
index c16e56a..b47b1d1 100644
--- a/src/include/ipxe/serial.h
+++ b/src/include/ipxe/serial.h
@@ -12,5 +12,6 @@ FILE_LICENCE ( GPL2_OR_LATER );
 extern void serial_putc ( int ch );
 extern int serial_getc ( void );
 extern int serial_ischar ( void );
+extern int serial_initialized;
 
 #endif /* _IPXE_SERIAL_H */
-- 
1.7.11.4