[PATCH v1 1/3] hw/char: Convert the Ibex UART to use the qdev Clock model

[Alistair Francis]

Conver the Ibex UART to use the recently added qdev-clock functions.

Signed-off-by: Alistair Francis <alistair.francis@wdc.com>
---
 include/hw/char/ibex_uart.h |  2 ++
 hw/char/ibex_uart.c         | 19 ++++++++++++++++++-
 2 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/include/hw/char/ibex_uart.h b/include/hw/char/ibex_uart.h
index 2bec772615..322bfffd8b 100644
--- a/include/hw/char/ibex_uart.h
+++ b/include/hw/char/ibex_uart.h
@@ -101,6 +101,8 @@ typedef struct {
     uint32_t uart_val;
     uint32_t uart_timeout_ctrl;
 
+    Clock *f_clk;
+
     CharBackend chr;
     qemu_irq tx_watermark;
     qemu_irq rx_watermark;
diff --git a/hw/char/ibex_uart.c b/hw/char/ibex_uart.c
index 45cd724998..f967e6919a 100644
--- a/hw/char/ibex_uart.c
+++ b/hw/char/ibex_uart.c
@@ -28,6 +28,7 @@
 #include "qemu/osdep.h"
 #include "hw/char/ibex_uart.h"
 #include "hw/irq.h"
+#include "hw/qdev-clock.h"
 #include "hw/qdev-properties.h"
 #include "migration/vmstate.h"
 #include "qemu/log.h"
@@ -330,7 +331,7 @@ static void ibex_uart_write(void *opaque, hwaddr addr,
         }
         if (value & UART_CTRL_NCO) {
             uint64_t baud = ((value & UART_CTRL_NCO) >> 16);
-            baud *= 1000;
+            baud *= clock_get_hz(s->f_clk);
             baud >>= 20;
 
             s->char_tx_time = (NANOSECONDS_PER_SECOND / baud) * 10;
@@ -385,6 +386,18 @@ static void ibex_uart_write(void *opaque, hwaddr addr,
     }
 }
 
+static void ibex_uart_clk_update(void *opaque)
+{
+    IbexUartState *s = opaque;
+
+    /* recompute uart's speed on clock change */
+    uint64_t baud = ((s->uart_ctrl & UART_CTRL_NCO) >> 16);
+    baud *= clock_get_hz(s->f_clk);
+    baud >>= 20;
+
+    s->char_tx_time = (NANOSECONDS_PER_SECOND / baud) * 10;
+}
+
 static void fifo_trigger_update(void *opaque)
 {
     IbexUartState *s = opaque;
@@ -444,6 +457,10 @@ static void ibex_uart_init(Object *obj)
 {
     IbexUartState *s = IBEX_UART(obj);
 
+    s->f_clk = qdev_init_clock_in(DEVICE(obj), "f_clock",
+                                  ibex_uart_clk_update, s);
+    clock_set_hz(s->f_clk, 50000000);
+
     sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->tx_watermark);
     sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->rx_watermark);
     sysbus_init_irq(SYS_BUS_DEVICE(obj), &s->tx_empty);
-- 
2.27.0