[tip: timers/clocksource] clocksource/drivers/timer-tegra186: Avoid 64-bit divide operation

From: tip-bot2 for Guenter Roeck
Date: Wed Jul 23 2025 - 03:19:03 EST


The following commit has been merged into the timers/clocksource branch of tip:

Commit-ID: eda68f63d2bbc16a485f9f0f4df79253ae5353f2
Gitweb: https://git.kernel.org/tip/eda68f63d2bbc16a485f9f0f4df79253ae5353f2
Author: Guenter Roeck <linux@xxxxxxxxxxxx>
AuthorDate: Sat, 14 Jun 2025 10:55:55 -07:00
Committer: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
CommitterDate: Tue, 15 Jul 2025 13:08:07 +02:00

clocksource/drivers/timer-tegra186: Avoid 64-bit divide operation

Building the driver on xtensa fails with

tensa-linux-ld: drivers/clocksource/timer-tegra186.o:
in function `tegra186_timer_remove':
timer-tegra186.c:(.text+0x350):
undefined reference to `__udivdi3'

Avoid the problem by rearranging the offending code to avoid the 64-bit
divide operation.

Fixes: 28c842c8b0f5 ("clocksource/drivers/timer-tegra186: Add WDIOC_GETTIMELEFT support")
Cc: Pohsun Su <pohsuns@xxxxxxxxxx>
Cc: Robert Lin <robelin@xxxxxxxxxx>
Signed-off-by: Guenter Roeck <linux@xxxxxxxxxxxx>
Reviewed-by: Jon Hunter <jonathanh@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20250614175556.922159-1-linux@xxxxxxxxxxxx
Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>
---
drivers/clocksource/timer-tegra186.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/clocksource/timer-tegra186.c b/drivers/clocksource/timer-tegra186.c
index 56a5342..76a5481 100644
--- a/drivers/clocksource/timer-tegra186.c
+++ b/drivers/clocksource/timer-tegra186.c
@@ -267,7 +267,7 @@ static unsigned int tegra186_wdt_get_timeleft(struct watchdog_device *wdd)
* counter value to the time of the counter expirations that
* remain.
*/
- timeleft += (((u64)wdt->base.timeout * USEC_PER_SEC) / 5) * (4 - expiration);
+ timeleft += ((u64)wdt->base.timeout * (USEC_PER_SEC / 5)) * (4 - expiration);

/*
* Convert the current counter value to seconds,