[PATCH can-next 1/2] can: rockchip_canfd: rkcanfd_timestamp_init(): rework delay calculation

Marc Kleine-Budde mkl at pengutronix.de
Wed Sep 11 01:45:25 PDT 2024


From: Arnd Bergmann <arnd at arndb.de>

Rework the delay calculation to only require a single 64-bit division.

Signed-off-by: Arnd Bergmann <arnd at arndb.de>
[mkl: port to on-top of existing 32-bit division fix]
Signed-off-by: Marc Kleine-Budde <mkl at pengutronix.de>
---
 drivers/net/can/rockchip/rockchip_canfd-timestamp.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/net/can/rockchip/rockchip_canfd-timestamp.c b/drivers/net/can/rockchip/rockchip_canfd-timestamp.c
index fb1a8f4e62172b06570b95e6f32c4c0f70fe1ea7..43d4b572181215c50dda9d4f8cdb2d22b7938b38 100644
--- a/drivers/net/can/rockchip/rockchip_canfd-timestamp.c
+++ b/drivers/net/can/rockchip/rockchip_canfd-timestamp.c
@@ -71,8 +71,8 @@ void rkcanfd_timestamp_init(struct rkcanfd_priv *priv)
 
 	max_cycles = div_u64(ULLONG_MAX, cc->mult);
 	max_cycles = min(max_cycles, cc->mask);
-	work_delay_ns = div_u64(clocksource_cyc2ns(max_cycles, cc->mult, cc->shift), 3);
-	priv->work_delay_jiffies = nsecs_to_jiffies(work_delay_ns);
+	work_delay_ns = clocksource_cyc2ns(max_cycles, cc->mult, cc->shift);
+	priv->work_delay_jiffies = div_u64(work_delay_ns, 3u * NSEC_PER_SEC / HZ);
 	INIT_DELAYED_WORK(&priv->timestamp, rkcanfd_timestamp_work);
 
 	netdev_dbg(priv->ndev, "clock=%lu.%02luMHz bitrate=%lu.%02luMBit/s div=%u rate=%lu.%02luMHz mult=%u shift=%u delay=%lus\n",

-- 
2.45.2





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