From 603989f6e85f578e073f9f7deb3396c403f2fb73 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?D=C3=A1niel=20Buga?= <bugadani@gmail.com>
Date: Wed, 18 Oct 2023 10:50:26 +0200
Subject: [PATCH] Fix overflow in timestamp calculation (#287)

---
 esp-wifi/src/timer/xtensa.rs | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/esp-wifi/src/timer/xtensa.rs b/esp-wifi/src/timer/xtensa.rs
index afce7ad8138..b3cbf9a5285 100644
--- a/esp-wifi/src/timer/xtensa.rs
+++ b/esp-wifi/src/timer/xtensa.rs
@@ -41,7 +41,9 @@ pub fn get_systimer_count() -> u64 {
         overflow = TIMER_OVERFLOWS.load(Ordering::Relaxed);
     }
 
-    (((overflow as u64) << 32) + counter_after as u64) * 40_000_000 / 240_000_000
+    // We have to precompute the divider to avoid overflow when multiplying.
+    const DIVIDER: u64 = 240_000_000 / TICKS_PER_SECOND;
+    (((overflow as u64) << 32) + counter_after as u64) / DIVIDER
 }
 
 pub fn setup_timer(mut timer1: TimeBase) {