ich9: add TCO interface emulation

This interface provides some registers within a 32-byte range and can be
acessed through PCI-to-LPC bridge interface (PMBASE + 0x60).

It's commonly used as a watchdog timer to detect system lockups through
SMIs that are generated -- if TCO_EN bit is set -- on every timeout. If
NO_REBOOT bit is not set in GCS (General Control and Status register),
the system will be resetted upon second timeout if TCO_RLD register
wasn't previously written to prevent timeout.

This patch adds support to TCO watchdog logic and few other features
like mapping NMIs to SMIs (NMI2SMI_EN bit), system intruder detection,
etc. are not implemented yet.

Signed-off-by: Paulo Alcantara <pcacjr@zytor.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

1 files changed, 2 insertions, 1 deletions

diff --git a/include/hw/boards.h b/include/hw/boards.h
index 6379901528..2aec9cbb12 100644
--- a/include/hw/boards.h
+++ b/include/hw/boards.h
@@ -99,7 +99,8 @@ struct MachineClass {
         no_floppy:1,
         no_cdrom:1,
         no_sdcard:1,
-        has_dynamic_sysbus:1;
+        has_dynamic_sysbus:1,
+        no_tco:1;
     int is_default;
     const char *default_machine_opts;
     const char *default_boot_order;