Cherry-pick 65d20f17 from master to r15. do not merge.tools_r15

Scrap IRQs for x86 system image.

This is a temporary fix that enables GoogleTV emulation on tools R15+ The permanent
solution would be to increase number of available IRQs from 16 to something more
appropriate. For now just:
1. Use IRQ3 for the events device.
2. Decrease number of TTY ports from 4 to 2.
These two measures would free up 3 IRQs, so the chances of running out of available
IRQs are significantly decreased.

Change-Id: I321c68eb5a152cb8bc166decd9b605942c50fc13

1 files changed, 14 insertions, 0 deletions

diff --git a/hw/pc.c b/hw/pc.c
index f44c44ec57..a8d609ad98 100644
--- a/hw/pc.c
+++ b/hw/pc.c
@@ -857,6 +857,11 @@ static struct goldfish_device event0_device = {
     .name = "goldfish_events",
     .id = 0,
     .size = 0x1000,
+    /* FIXME: This is just a work around before we have a permanent fix on
+     * increasing number of IRQs available for x86 sysimages. IRQ3 is normally
+     * assigned to COM2/COM4, and we have our own custom IRQs for those. So,
+     * it's safe to reserve it for the events device. */
+    .irq = 3,
     .irq_count = 1
 };
 
@@ -1115,7 +1120,16 @@ static void pc_init1(ram_addr_t ram_size,
     }
 
     goldfish_tty_add(serial_hds[0], 0, 0, 0);
+    /* FIXME: This is just a work around before we have a permanent fix on
+     * increasing number of IRQs available for x86 sysimages. In order to free up
+     * some IRQs for a better use, we limit number of TTY devices by 2. Normally
+     * we don't need more than that, so always having 4 of them would waste two
+     * precious IRQs. */
+#if 0
     for(i = 1; i < MAX_SERIAL_PORTS; i++) {
+#else
+    for(i = 1; i < 2; i++) {
+#endif
         if(serial_hds[i]) {
             goldfish_tty_add(serial_hds[i], i, 0, 0);
         }