nrfx: hal: nrf_grtc: Remove readback from event clear

nordic-krch · nordic-krch · commit f0283fb9d47f · 2025-05-09T14:00:49.000+02:00
Readback was added to ensure that interrupt is not triggered spuriously.
It may only happen if event clearing is done just before exiting the
interrupt. It is not the case in the GRTC driver. Each access to the
register interface is costly (~160 320MHz cycles) so it must be avoided
if possible.

Signed-off-by: Krzysztof Chruściński &lt;krzysztof.chruscinski@nordicsemi.no&gt;
diff --git a/nrfx/hal/nrf_grtc.h b/nrfx/hal/nrf_grtc.h
@@ -1559,7 +1559,6 @@ NRF_STATIC_INLINE void nrf_grtc_event_clear(NRF_GRTC_Type * p_reg, nrf_grtc_even
 #endif
 
     *((volatile uint32_t *)((uint8_t *)p_reg + (uint32_t)event)) = 0x0UL;
-    nrf_event_readback((uint8_t *)p_reg + (uint32_t)event);
 }
 
 #if NRF_GRTC_HAS_RTCOUNTER

Original file line number	Diff line number	Diff line change
`@@ -1559,7 +1559,6 @@ NRF_STATIC_INLINE void nrf_grtc_event_clear(NRF_GRTC_Type * p_reg, nrf_grtc_even`
`1559`	`1559`	`#endif`
`1560`	`1560`
`1561`	`1561`	`((volatile uint32_t )((uint8_t *)p_reg + (uint32_t)event)) = 0x0UL;`
`1562`		`- nrf_event_readback((uint8_t *)p_reg + (uint32_t)event);`
`1563`	`1562`	`}`
`1564`	`1563`
`1565`	`1564`	`#if NRF_GRTC_HAS_RTCOUNTER`