[HVM] Allow more dynamic use of the qemu serial lines by allowing the Summagraphics...

qemu will emulate up to 4 serial lines (COM1 - COM4).  One of these
lines supports a Summagraphics protocol.  This has changed recently,
and it's now always COM2.  This patch allows the user to specify
to qemu which lines should be serial lines, and the code will place
the Summagraphics compatible line at just above the last specified
serial line.  qemu defaults serial line 0 (COM1) to be "vc", resulting
in the Summagraphics support residing on COM2. This is in keeping
with the current behavior.

The results, via qemu command line, are:
<none>                                    COM2
-serial x                                 COM2
-serial x -serial x                       COM3
-serial x -serial x -serial x             COM4
-serial x -serial x -serial x -serial x  <none>

The results are deterministic, and allow the use of up to 4 serial
lines including none with Summagraphics support.  There is no
change from current behavior, unless requested.

Signed-off-by: Ben Thomas <ben@virtualiron.com>

diff --git a/tools/ioemu/hw/pc.c b/tools/ioemu/hw/pc.c
index d762f0e9ee1c976cae83e013403cb90e56ae0881..247375f54412b97718a3759b8c5bf5f42882a989 100644 (file)
--- a/tools/ioemu/hw/pc.c
+++ b/tools/ioemu/hw/pc.c
@@ -537,8 +537,11 @@ void pc_init(uint64_t ram_size, int vga_ram_size, int boot_device,
     for(i = 0; i < MAX_SERIAL_PORTS; i++) {
         if (serial_hds[i]) {
             sp = serial_init(serial_io[i], serial_irq[i], serial_hds[i]);
-            if (i == SUMMA_PORT)
+            if (i == serial_summa_port) {
                summa_init(sp, serial_hds[i]);
+               fprintf(stderr, "Serial port %d (COM%d) initialized for Summagraphics\n",
+                       i, i+1);
+           }
         }
     }
 

diff --git a/tools/ioemu/vl.c b/tools/ioemu/vl.c
index 08e38449bb76a7e963ce7c57183bc1bef9b81926..a39ff622529500b668da7076dae49a4b3a2f41ed 100644 (file)
--- a/tools/ioemu/vl.c
+++ b/tools/ioemu/vl.c
@@ -146,6 +146,7 @@ int full_screen = 0;
 int repeat_key = 1;
 TextConsole *vga_console;
 CharDriverState *serial_hds[MAX_SERIAL_PORTS];
+int serial_summa_port = -1;
 int xc_handle;
 time_t timeoffset = 0;
 
@@ -2588,8 +2589,8 @@ int main(int argc, char **argv)
     pstrcpy(monitor_device, sizeof(monitor_device), "vc");
 
     pstrcpy(serial_devices[0], sizeof(serial_devices[0]), "vc");
-    pstrcpy(serial_devices[1], sizeof(serial_devices[1]), "null");
-    for(i = 2; i < MAX_SERIAL_PORTS; i++)
+    serial_summa_port = -1;
+    for(i = 1; i < MAX_SERIAL_PORTS; i++)
         serial_devices[i][0] = '\0';
     serial_device_index = 0;
 
@@ -3173,6 +3174,20 @@ int main(int argc, char **argv)
     }
     monitor_init(monitor_hd, !nographic);
 
+    /* Find which port should be the Summagraphics port */
+    /* It's the first unspecified serial line. Note that COM1 is set */
+    /* by default, so the Summagraphics port would be COM2 or higher */
+
+    for(i = 0; i < MAX_SERIAL_PORTS; i++) {
+      if (serial_devices[i][0] != '\0')
+       continue;
+      serial_summa_port = i;
+      pstrcpy(serial_devices[serial_summa_port], sizeof(serial_devices[0]), "null");
+      break;
+    }
+
+    /* Now, open the ports */
+
     for(i = 0; i < MAX_SERIAL_PORTS; i++) {
         if (serial_devices[i][0] != '\0') {
             serial_hds[i] = qemu_chr_open(serial_devices[i]);

diff --git a/tools/ioemu/vl.h b/tools/ioemu/vl.h
index 54a84c6bd433905f463f4992301f2e9dbd16f196..bb557497537f9e610ab3def81fb51be3de28deec 100644 (file)
--- a/tools/ioemu/vl.h
+++ b/tools/ioemu/vl.h
@@ -238,9 +238,9 @@ void console_select(unsigned int index);
 /* serial ports */
 
 #define MAX_SERIAL_PORTS 4
-#define SUMMA_PORT     1
 
 extern CharDriverState *serial_hds[MAX_SERIAL_PORTS];
+extern int serial_summa_port;
 
 /* network redirectors support */