add isa-debug-exit device.

When present it makes qemu exit on any write.
Mapped to port 0x501 by default.

Without this patch Anthony doesn't allow me to
remove the bochs bios debug ports because his
test suite uses this.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>

2 files changed, 76 insertions, 1 deletions

diff --git a/hw/debugexit.c b/hw/debugexit.c
new file mode 100644
index 0000000..90642eb
--- /dev/null
+++ b/hw/debugexit.c
@@ -0,0 +1,75 @@
+/*
+ * debug exit port emulation
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 or
+ * (at your option) any later version.
+ */
+
+#include "hw.h"
+#include "isa.h"
+
+#define TYPE_ISA_DEBUG_EXIT_DEVICE "isa-debug-exit"
+#define ISA_DEBUG_EXIT_DEVICE(obj) \
+     OBJECT_CHECK(ISADebugExitState, (obj), TYPE_ISA_DEBUG_EXIT_DEVICE)
+
+typedef struct ISADebugExitState {
+    ISADevice parent_obj;
+
+    uint32_t iobase;
+    uint32_t iosize;
+    MemoryRegion io;
+} ISADebugExitState;
+
+static void debug_exit_write(void *opaque, hwaddr addr, uint64_t val,
+                             unsigned width)
+{
+    exit((val << 1) | 1);
+}
+
+static const MemoryRegionOps debug_exit_ops = {
+    .write = debug_exit_write,
+    .valid.min_access_size = 1,
+    .valid.max_access_size = 4,
+    .endianness = DEVICE_LITTLE_ENDIAN,
+};
+
+static int debug_exit_initfn(ISADevice *dev)
+{
+    ISADebugExitState *isa = ISA_DEBUG_EXIT_DEVICE(dev);
+
+    memory_region_init_io(&isa->io, &debug_exit_ops, isa,
+                          TYPE_ISA_DEBUG_EXIT_DEVICE, isa->iosize);
+    memory_region_add_subregion(isa_address_space_io(dev),
+                                isa->iobase, &isa->io);
+    return 0;
+}
+
+static Property debug_exit_properties[] = {
+    DEFINE_PROP_HEX32("iobase", ISADebugExitState, iobase, 0x501),
+    DEFINE_PROP_HEX32("iosize", ISADebugExitState, iosize, 0x02),
+    DEFINE_PROP_END_OF_LIST(),
+};
+
+static void debug_exit_class_initfn(ObjectClass *klass, void *data)
+{
+    DeviceClass *dc = DEVICE_CLASS(klass);
+    ISADeviceClass *ic = ISA_DEVICE_CLASS(klass);
+    ic->init = debug_exit_initfn;
+    dc->props = debug_exit_properties;
+}
+
+static TypeInfo debug_exit_info = {
+    .name          = TYPE_ISA_DEBUG_EXIT_DEVICE,
+    .parent        = TYPE_ISA_DEVICE,
+    .instance_size = sizeof(ISADebugExitState),
+    .class_init    = debug_exit_class_initfn,
+};
+
+static void debug_exit_register_types(void)
+{
+    type_register_static(&debug_exit_info);
+}
+
+type_init(debug_exit_register_types)
diff --git a/hw/i386/Makefile.objs b/hw/i386/Makefile.objs
index 257f3c1..2ba04db 100644
--- a/hw/i386/Makefile.objs
+++ b/hw/i386/Makefile.objs
@@ -3,7 +3,7 @@ obj-y += apic_common.o apic.o kvmvapic.o
 obj-y += sga.o ioapic_common.o ioapic.o piix_pci.o
 obj-y += vmport.o
 obj-y += pci/pci-hotplug.o smbios.o wdt_ib700.o
-obj-y += debugcon.o multiboot.o
+obj-y += debugcon.o debugexit.o multiboot.o
 obj-y += pc_piix.o
 obj-y += pc_sysfw.o
 obj-y += lpc_ich9.o q35.o pc_q35.o