[nrf fromlist] soc: nordic: ironside: dvfs: check abb analog status more than once

Added ABB analog status lock read retries if needed.
After cpu idle ABB macro may need some time to initialize
and report status locked. Attempts cound can be configured
using Kconfig option.

Upstream PR #: 93595

Signed-off-by: Łukasz Stępnicki <[email protected]>

Author: lstnl

soc/nordic/ironside/Kconfig

@@ -65,11 +65,12 @@ config NRF_IRONSIDE_DVFS_SERVICE
 
 if NRF_IRONSIDE_DVFS_SERVICE
 
-config NRF_IRONSIDE_DVFS_OPPOINT_CHANGE_MUTEX_TIMEOUT_MS
-	int "IRONSside DVFS change oppoint mutex timeout"
-	default 100
+config NRF_IRONSIDE_ABB_STATUSANA_CHECK_MAX_ATTEMPTS
+	int "IRONSside DVFS ABB analog status check maximum attempts"
+	range 0 255
+	default 50
 	help
-	  Maximum timeout when waiting for DVFS oppoint change mutex lock.
+	  Maximum attempts with 10us intervals before busy status will be reported.
 
 endif # NRF_IRONSIDE_DVFS_SERVICE
 

soc/nordic/ironside/dvfs.c

@@ -18,6 +18,9 @@ static enum ironside_dvfs_oppoint current_dvfs_oppoint = IRONSIDE_DVFS_OPP_HIGH;
 #error "Unsupported SoC series for IronSide DVFS"
 #endif
 
+#define ABB_STATUSANA_CHECK_MAX_ATTEMPTS (CONFIG_NRF_IRONSIDE_ABB_STATUSANA_CHECK_MAX_ATTEMPTS)
+#define ABB_STATUSANA_CHECK_INTERVAL_US  (10U)
+
 struct dvfs_hsfll_data_t {
 	uint32_t new_f_mult;
 	uint32_t new_f_trim_entry;
@@ -129,6 +132,13 @@ static inline bool ironside_dvfs_is_abb_locked(NRF_ABB_Type *abb)
 	/* Temporary workaround until STATUSANA register is visible. */
 	volatile const uint32_t *statusana = (uint32_t *)abb + ABB_STATUSANA_REG_OFFSET;
 
+	uint8_t status_read_attempts = ABB_STATUSANA_CHECK_MAX_ATTEMPTS;
+
+	while ((*statusana & ABB_STATUSANA_LOCKED_L_Msk) == 0 && status_read_attempts > 0) {
+		k_busy_wait(ABB_STATUSANA_CHECK_INTERVAL_US);
+		status_read_attempts--;
+	}
+
 	return ((*statusana & ABB_STATUSANA_LOCKED_L_Msk) != 0);
 }