1 files changed, 89 insertions, 0 deletions
diff --git a/qemu/roms/seabios/src/hw/serialio.c b/qemu/roms/seabios/src/hw/serialio.c
new file mode 100644
index 000000000..6486fc086
--- /dev/null
+++ b/qemu/roms/seabios/src/hw/serialio.c
@@ -0,0 +1,89 @@
+// Low-level serial (and serial-like) device access.
+//
+// Copyright (C) 2008-1013  Kevin O'Connor <kevin@koconnor.net>
+//
+// This file may be distributed under the terms of the GNU LGPLv3 license.
+
+#include "config.h" // CONFIG_DEBUG_SERIAL
+#include "fw/paravirt.h" // RunningOnQEMU
+#include "output.h" // dprintf
+#include "serialio.h" // serial_debug_preinit
+#include "x86.h" // outb
+
+
+/****************************************************************
+ * Serial port debug output
+ ****************************************************************/
+
+#define DEBUG_TIMEOUT 100000
+
+// Setup the debug serial port for output.
+void
+serial_debug_preinit(void)
+{
+    if (!CONFIG_DEBUG_SERIAL)
+        return;
+    // setup for serial logging: 8N1
+    u8 oldparam, newparam = 0x03;
+    oldparam = inb(CONFIG_DEBUG_SERIAL_PORT+SEROFF_LCR);
+    outb(newparam, CONFIG_DEBUG_SERIAL_PORT+SEROFF_LCR);
+    // Disable irqs
+    u8 oldier, newier = 0;
+    oldier = inb(CONFIG_DEBUG_SERIAL_PORT+SEROFF_IER);
+    outb(newier, CONFIG_DEBUG_SERIAL_PORT+SEROFF_IER);
+
+    if (oldparam != newparam || oldier != newier)
+        dprintf(1, "Changing serial settings was %x/%x now %x/%x\n"
+                , oldparam, oldier, newparam, newier);
+}
+
+// Write a character to the serial port.
+static void
+serial_debug(char c)
+{
+    if (!CONFIG_DEBUG_SERIAL)
+        return;
+    int timeout = DEBUG_TIMEOUT;
+    while ((inb(CONFIG_DEBUG_SERIAL_PORT+SEROFF_LSR) & 0x20) != 0x20)
+        if (!timeout--)
+            // Ran out of time.
+            return;
+    outb(c, CONFIG_DEBUG_SERIAL_PORT+SEROFF_DATA);
+}
+
+void
+serial_debug_putc(char c)
+{
+    if (c == '\n')
+        serial_debug('\r');
+    serial_debug(c);
+}
+
+// Make sure all serial port writes have been completely sent.
+void
+serial_debug_flush(void)
+{
+    if (!CONFIG_DEBUG_SERIAL)
+        return;
+    int timeout = DEBUG_TIMEOUT;
+    while ((inb(CONFIG_DEBUG_SERIAL_PORT+SEROFF_LSR) & 0x60) != 0x60)
+        if (!timeout--)
+            // Ran out of time.
+            return;
+}
+
+
+/****************************************************************
+ * QEMU debug port
+ ****************************************************************/
+
+u16 DebugOutputPort VARFSEG = 0x402;
+
+// Write a character to the special debugging port.
+void
+qemu_debug_putc(char c)
+{
+    if (CONFIG_DEBUG_IO && runningOnQEMU())
+        // Send character to debug port.
+        outb(c, GET_GLOBAL(DebugOutputPort));
+}