[PATCH 1/3] clocksource/drivers/nxp-stm: Fix max_delta overflow on 64-bit platforms

[Enric Balletbo i Serra via B4 Relay <devnull+eballetb.redhat.com@kernel.org>]

From: Enric Balletbo i Serra <eballetb@redhat.com>

The NXP STM timer has a 32-bit counter and 32-bit compare registers.
Using ULONG_MAX as the max_delta parameter for
clockevents_config_and_register() is incorrect on 64-bit platforms where
unsigned long is 64 bits, as this exceeds the hardware's capability.

Cap the max_delta to 0x7FFFFFFFU to match the 32-bit compare channel
width, avoiding potential timer event misses or unexpected delays caused
by programming an unreachable compare value.

Fixes: cec32ac75827 ("clocksource/drivers/nxp-timer: Add the System Timer Module for the s32gx platforms")

Signed-off-by: Enric Balletbo i Serra <eballetb@redhat.com>
---
 drivers/clocksource/timer-nxp-stm.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/clocksource/timer-nxp-stm.c b/drivers/clocksource/timer-nxp-stm.c
index 6fe098a4a33f..ee249fed1b91 100644
--- a/drivers/clocksource/timer-nxp-stm.c
+++ b/drivers/clocksource/timer-nxp-stm.c
@@ -346,7 +346,7 @@ static int nxp_stm_clockevent_starting_cpu(unsigned int cpu)
 	 * minimum ticks = (rate / MICRO) * 2
 	 */
 	clockevents_config_and_register(&stm_timer->ced, stm_timer->rate,
-					(stm_timer->rate / MICRO) * 2, ULONG_MAX);
+					(stm_timer->rate / MICRO) * 2, 0x7FFFFFFFU);
 
 	return 0;
 }

-- 
2.52.0