timer: Fix busywait inline assembly

MuhammedZamroodh · MuhammedZamroodh · commit 4afe76623bc8 · 2025-11-28T12:48:52.000+05:30
Make inline assembly portable/maintainable

Signed-off-by: Muhammed Zamroodh &lt;muhammed.zamroodh@ignitarium.com&gt;
diff --git a/drivers/timer/mchp_dspic33_timer.c b/drivers/timer/mchp_dspic33_timer.c
@@ -93,10 +93,9 @@ static void initialize_timer(void)
 #ifdef CONFIG_ARCH_HAS_CUSTOM_BUSY_WAIT
 void arch_busy_wait(uint32_t usec_to_wait)
 {
-	ARG_UNUSED(usec_to_wait);
-	__asm__ volatile("sl.l w0,#0x03,w0\n\t"
-			 "repeat.w w0\n\t"
-			 "nop\n\n\t");
+	usec_to_wait <<= 3;
+	__asm__ volatile("repeat.w %0\n\t"
+			 "nop\n\t"::"r"(usec_to_wait));
 }
 #endif
 

Original file line number	Diff line number	Diff line change
`@@ -93,10 +93,9 @@ static void initialize_timer(void)`
`93`	`93`	`#ifdef CONFIG_ARCH_HAS_CUSTOM_BUSY_WAIT`
`94`	`94`	`void arch_busy_wait(uint32_t usec_to_wait)`
`95`	`95`	`{`
`96`		`- ARG_UNUSED(usec_to_wait);`
`97`		`- __asm__ volatile("sl.l w0,#0x03,w0\n\t"`
`98`		`- "repeat.w w0\n\t"`
`99`		`- "nop\n\n\t");`
	`96`	`+ usec_to_wait <<= 3;`
	`97`	`+ __asm__ volatile("repeat.w %0\n\t"`
	`98`	`+ "nop\n\t"::"r"(usec_to_wait));`
`100`	`99`	`}`
`101`	`100`	`#endif`
`102`	`101`