Some chipsets provide 16650 compatible UART with exhanced
features. The BCM2835 provides a register to directly set
the baudrate divisor register without having to use the
LABD bit.

Add a helper to allow models to directly set the divisor.

Signed-off-by: Philippe Mathieu-Daudé <philmd@redhat.com>
---
 hw/char/serial.c         | 6 ++++++
 include/hw/char/serial.h | 1 +
 2 files changed, 7 insertions(+)

diff --git a/hw/char/serial.c b/hw/char/serial.c
index b4aa250950..12eb93705d 100644
--- a/hw/char/serial.c
+++ b/hw/char/serial.c
@@ -191,6 +191,12 @@ static void serial_update_parameters(SerialState *s)
            speed, parity, data_bits, stop_bits);
 }
 
+void serial_set_divider(SerialState *s, uint16_t divider)
+{
+    s->divider = divider;
+    serial_update_parameters(s);
+}
+
 static void serial_update_msl(SerialState *s)
 {
     uint8_t omsr;
diff --git a/include/hw/char/serial.h b/include/hw/char/serial.h
index 8be3d8a4f9..ef211f695d 100644
--- a/include/hw/char/serial.h
+++ b/include/hw/char/serial.h
@@ -83,6 +83,7 @@ extern const MemoryRegionOps serial_io_ops;
 void serial_realize_core(SerialState *s, Error **errp);
 void serial_exit_core(SerialState *s);
 void serial_set_frequency(SerialState *s, uint32_t frequency);
+void serial_set_divider(SerialState *s, uint16_t divider);
 
 /* legacy pre qom */
 SerialState *serial_init(int base, qemu_irq irq, int baudbase,
-- 
2.20.1