+Damien
On 6/30/20 10:12 PM, Alistair Francis wrote:
> Conver the Ibex UART to use the recently added qdev-clock functions.
Yeah! This is our first user \o/
>
> Signed-off-by: Alistair Francis <alistair.fran...@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);
UART_CTRL_NCO is defined as:
#define UART_CTRL_NCO (0xFFFF << 16)
Note for later, convert to the clearer registerfields API?
> - 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;
Maybe worth to extract:
uint64_t ibex_uart_get_baud(IbexUartState *s)
{
uint64_t baud;
baud = ((s->uart_ctrl & UART_CTRL_NCO) >> 16);
baud *= clock_get_hz(s->f_clk);
baud >>= 20;
return baud;
}
> +
> + 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);
Can you add a definition for this 50 MHz value:
Otherwise:
Reviewed-by: Philippe Mathieu-Daudé <f4...@amsat.org>
> +
> 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);
>
