Upgrade emulated UART to 16550A (Stefano Stabellini)

This patch upgrades the emulated UART to 16550A, the code comes from
xen-unstable. The main improvement was introduced with the following patch and
subsequent email thread:

http://lists.xensource.com/archives/html/xen-devel/2007-12/msg00129.html

The changes compared to previous version are:

- change clock_gettime to qemu_get_clock

- no token bucket anymore;

- fixed a small bug handling IRQs; this was the problem that prevented
kgdb to work over the serial (thanks to Jason Wessel for the help
spotting and reproducing this bug).

- many many style fixes;

- savevm version number increased;

- not including termios.h and sys/ioctl.h anymore, declaring static
constants in qemu-char.h instead;
Signed-off-by: NStefano Stabellini <stefano.stabellini@eu.citrix.com>
Signed-off-by: NAnthony Liguori <aliguori@us.ibm.com>



git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@4993 c046a42c-6fe2-441c-8c8c-71466251a162

qemu-char.h

@@ -28,6 +28,16 @@ typedef struct {
 #define CHR_IOCTL_PP_EPP_WRITE_ADDR  10
 #define CHR_IOCTL_PP_EPP_WRITE       11
 
+#define CHR_IOCTL_SERIAL_SET_TIOCM   12
+#define CHR_IOCTL_SERIAL_GET_TIOCM   13
+
+#define CHR_TIOCM_CTS	0x020
+#define CHR_TIOCM_CAR	0x040
+#define CHR_TIOCM_DSR	0x100
+#define CHR_TIOCM_RI	0x080
+#define CHR_TIOCM_DTR	0x002
+#define CHR_TIOCM_RTS	0x004
+
 typedef void IOEventHandler(void *opaque, int event);
 
 struct CharDriverState {

vl.c

@@ -2721,6 +2721,37 @@ static int tty_serial_ioctl(CharDriverState *chr, int cmd, void *arg)
                 tcsendbreak(s->fd_in, 1);
         }
         break;
+    case CHR_IOCTL_SERIAL_GET_TIOCM:
+        {
+            int sarg = 0;
+            int *targ = (int *)arg;
+            ioctl(s->fd_in, TIOCMGET, &sarg);
+            *targ = 0;
+            if (sarg | TIOCM_CTS)
+                *targ |= CHR_TIOCM_CTS;
+            if (sarg | TIOCM_CAR)
+                *targ |= CHR_TIOCM_CAR;
+            if (sarg | TIOCM_DSR)
+                *targ |= CHR_TIOCM_DSR;
+            if (sarg | TIOCM_RI)
+                *targ |= CHR_TIOCM_RI;
+            if (sarg | TIOCM_DTR)
+                *targ |= CHR_TIOCM_DTR;
+            if (sarg | TIOCM_RTS)
+                *targ |= CHR_TIOCM_RTS;
+        }
+        break;
+    case CHR_IOCTL_SERIAL_SET_TIOCM:
+        {
+            int sarg = *(int *)arg;
+            int targ = 0;
+            if (sarg | CHR_TIOCM_DTR)
+                targ |= TIOCM_DTR;
+            if (sarg | CHR_TIOCM_RTS)
+                targ |= TIOCM_RTS;
+            ioctl(s->fd_in, TIOCMSET, &targ);
+        }
+        break;
     default:
         return -ENOTSUP;
     }