Hello Jiri,
On Tue, Mar 02, 2021 at 07:21:40AM +0100, Jiri Slaby wrote:
> This really eliminates multiplications from the assembly. I would have
> thought they are optimized by inlining ktime_set, but not on x86_64 with
> gcc 10.
>
> Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
> Cc: Shawn Guo <shawnguo@xxxxxxxxxx>
> Cc: Sascha Hauer <s.hauer@xxxxxxxxxxxxxx>
> Cc: Pengutronix Kernel Team <kernel@xxxxxxxxxxxxxx>
> Cc: Fabio Estevam <festevam@xxxxxxxxx>
> Cc: NXP Linux Team <linux-imx@xxxxxxx>
> ---
> drivers/tty/serial/imx.c | 6 +-----
> 1 file changed, 1 insertion(+), 5 deletions(-)
>
> diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
> index 8257597d034d..3f69356937ef 100644
> --- a/drivers/tty/serial/imx.c
> +++ b/drivers/tty/serial/imx.c
> @@ -394,11 +394,7 @@ static void imx_uart_rts_inactive(struct imx_port *sport, u32 *ucr2)
>
> static void start_hrtimer_ms(struct hrtimer *hrt, unsigned long msec)
> {
> - long sec = msec / MSEC_PER_SEC;
> - long nsec = (msec % MSEC_PER_SEC) * 1000000;
> - ktime_t t = ktime_set(sec, nsec);
> -
> - hrtimer_start(hrt, t, HRTIMER_MODE_REL);
> + hrtimer_start(hrt, ms_to_ktime(msec), HRTIMER_MODE_REL);
> }
What about:
diff --git a/drivers/tty/serial/imx.c b/drivers/tty/serial/imx.c
index 8257597d034d..8731d4f82cb8 100644
--- a/drivers/tty/serial/imx.c
+++ b/drivers/tty/serial/imx.c
@@ -392,15 +392,6 @@ static void imx_uart_rts_inactive(struct imx_port *sport, u32 *ucr2)
mctrl_gpio_set(sport->gpios, sport->port.mctrl);
}
-static void start_hrtimer_ms(struct hrtimer *hrt, unsigned long msec)
-{
- long sec = msec / MSEC_PER_SEC;
- long nsec = (msec % MSEC_PER_SEC) * 1000000;
- ktime_t t = ktime_set(sec, nsec);
-
- hrtimer_start(hrt, t, HRTIMER_MODE_REL);
-}
-
/* called with port.lock taken and irqs off */
static void imx_uart_start_rx(struct uart_port *port)
{
@@ -457,8 +448,9 @@ static void imx_uart_stop_tx(struct uart_port *port)
if (port->rs485.flags & SER_RS485_ENABLED) {
if (sport->tx_state == SEND) {
sport->tx_state = WAIT_AFTER_SEND;
- start_hrtimer_ms(&sport->trigger_stop_tx,
- port->rs485.delay_rts_after_send);
+ hrtimer_start(&sport->trigger_stop_tx,
+ ms_to_ktime(port->rs485.delay_rts_after_send),
+ HRTIMER_MODE_REL);
return;
}
@@ -697,8 +689,9 @@ static void imx_uart_start_tx(struct uart_port *port)
imx_uart_stop_rx(port);
sport->tx_state = WAIT_AFTER_RTS;
- start_hrtimer_ms(&sport->trigger_start_tx,
- port->rs485.delay_rts_before_send);
+ hrtimer_start(&sport->trigger_start_tx,
+ ms_to_ktime(port->rs485.delay_rts_before_send),
+ HRTIMER_MODE_REL);
return;
}
instead?
Best regards
Uwe
--
Pengutronix e.K. | Uwe Kleine-König |
Industrial Linux Solutions | https://www.pengutronix.de/ |
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