timing: fix ARM Cortex-M timing functions wrap-around issue

stomschik-ask · mmahadevan108 · commit 1647ad5c0a95 · 2024-10-29T07:09:34.000-05:00
Added casts to uint32_t in arch_timing_cycles_get() to handle the
wrap-around of the 32-bit cycle counter correctly.

Signed-off-by: Simon Tomschik &lt;simon.tomschik@askgroup.global&gt;
diff --git a/arch/arm/core/cortex_m/timing.c b/arch/arm/core/cortex_m/timing.c
@@ -104,7 +104,7 @@ timing_t arch_timing_counter_get(void)
 uint64_t arch_timing_cycles_get(volatile timing_t *const start,
 				volatile timing_t *const end)
 {
-	return (*end - *start);
+	return ((uint32_t)*end - (uint32_t)*start);
 }
 
 uint64_t arch_timing_freq_get(void)

Original file line number	Diff line number	Diff line change
`@@ -104,7 +104,7 @@ timing_t arch_timing_counter_get(void)`
`104`	`104`	`uint64_t arch_timing_cycles_get(volatile timing_t *const start,`
`105`	`105`	`volatile timing_t *const end)`
`106`	`106`	`{`
`107`		`- return (end - start);`
	`107`	`+ return ((uint32_t)end - (uint32_t)start);`
`108`	`108`	`}`
`109`	`109`
`110`	`110`	`uint64_t arch_timing_freq_get(void)`