With the pc-q35-2.4 machine type, if the user creates an ISA FDC manually:
-device isa-fdc,driveA=drive-fdc0-0-0 \
-drive file=...,if=none,id=drive-fdc0-0-0,format=raw
then the board-default FDC will be skipped, and only the explicitly
requested FDC will exist. qtree-wise, this is correct; however such an FDC
is currently not registered in the CMOS, because that code is only reached
for the board-default FDC.
The pc_cmos_init_late() one-shot reset handler -- one-shot because the
CMOS is not reprogrammed during warm reset -- should search for a single,
explicitly created ISA FDC device, if there has been no board default, and
reprogram the CMOS if found.
Cc: Jan Tomko <jto...@redhat.com>
Cc: John Snow <js...@redhat.com>
Cc: Markus Armbruster <arm...@redhat.com>
Cc: Paolo Bonzini <pbonz...@redhat.com>
Reported-by: Jan Tomko <jto...@redhat.com>
Suggested-by: Markus Armbruster <arm...@redhat.com>
Signed-off-by: Laszlo Ersek <ler...@redhat.com>
---
hw/i386/pc.c | 46 ++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 46 insertions(+)
diff --git a/hw/i386/pc.c b/hw/i386/pc.c
index 1ca0cdd..47a3082 100644
--- a/hw/i386/pc.c
+++ b/hw/i386/pc.c
@@ -333,8 +333,30 @@ static void pc_cmos_init_floppy(ISADevice *rtc_state,
ISADevice *floppy)
typedef struct pc_cmos_init_late_arg {
ISADevice *rtc_state;
BusState *idebus[2];
+ ISADevice *board_floppy;
} pc_cmos_init_late_arg;
+typedef struct check_fdc_state {
+ ISADevice *floppy;
+ bool multiple;
+} CheckFdcState;
+
+static int check_fdc(Object *obj, void *opaque)
+{
+ CheckFdcState *state = opaque;
+ Object *fdc;
+
+ fdc = object_dynamic_cast(obj, TYPE_ISA_FDC);
+ if (fdc) {
+ if (state->floppy) {
+ state->multiple = true;
+ } else {
+ state->floppy = ISA_DEVICE(obj);
+ }
+ }
+ return 0;
+}
+
static void pc_cmos_init_late(void *opaque)
{
pc_cmos_init_late_arg *arg = opaque;
@@ -372,6 +394,29 @@ static void pc_cmos_init_late(void *opaque)
}
rtc_set_memory(s, 0x39, val);
+ /*
+ * If the board initialization code created no FDC, but exactly one FDC has
+ * been created since then explicitly, then we configure the CMOS registers
+ * now, in accordance with that one FDC.
+ */
+ if (arg->board_floppy == NULL) {
+ static const char * const paths[] = { "/peripheral",
+ "/peripheral-anon", NULL };
+ const char * const * path;
+ CheckFdcState state = { 0 };
+
+ for (path = paths; *path; ++path) {
+ Object *container;
+
+ container = container_get(qdev_get_machine(), *path);
+ object_child_foreach(container, check_fdc, &state);
+ }
+
+ if (state.floppy && !state.multiple) {
+ pc_cmos_init_floppy(s, state.floppy);
+ }
+ }
+
qemu_unregister_reset(pc_cmos_init_late, opaque);
}
@@ -447,6 +492,7 @@ void pc_cmos_init(ram_addr_t ram_size, ram_addr_t
above_4g_mem_size,
arg.rtc_state = s;
arg.idebus[0] = idebus0;
arg.idebus[1] = idebus1;
+ arg.board_floppy = floppy;
qemu_register_reset(pc_cmos_init_late, &arg);
}
--
1.8.3.1
