drivers: stm32_bsec: fix timeouts initializations

If OP-TEE is rescheduled right after the timeouts are initialized in
power_down_safmem() and power_up_safmem(), the timeout might be elapsed
when resuming the function. This would cause the while loop to break
instantly and there will be no delay between configuring the registers
and reading the status.

Initializes the timeout after configuring the registers.

Signed-off-by: Gatien Chevallier <gatien.chevallier@foss.st.com>
Change-Id: Idd7e9151cdddb1db60e775f5b59ec5b8a1639815
Reviewed-on: https://gerrit.st.com/c/mpu/oe/optee/optee_os/+/312894
ACI: CITOOLS <MDG-smet-aci-reviews@list.st.com>
ACI: CIBUILD <MDG-smet-aci-builds@list.st.com>
Reviewed-by: Etienne CARRIERE <etienne.carriere@foss.st.com>
Reviewed-by: Gatien CHEVALLIER <gatien.chevallier@st.com>
Tested-by: Gatien CHEVALLIER <gatien.chevallier@st.com>
Domain-Review: Gatien CHEVALLIER <gatien.chevallier@st.com>

core/drivers/stm32_bsec.c

@@ -217,15 +217,12 @@ static TEE_Result check_no_error(uint32_t otp_id, bool check_disturbed)
 
 static TEE_Result power_up_safmem(void)
 {
-	uint64_t timeout_ref = timeout_init_us(BSEC_TIMEOUT_US);
+	uint64_t timeout_ref = 0;
 
 	io_mask32(bsec_base() + BSEC_OTP_CONF_OFF, BSEC_CONF_POWER_UP_MASK,
 		  BSEC_CONF_POWER_UP_MASK);
 
-	/*
-	 * If a timeout is detected, test the condition again to consider
-	 * cases where timeout is due to the executing TEE thread rescheduling.
-	 */
+	timeout_ref = timeout_init_us(BSEC_TIMEOUT_US);
 	while (!timeout_elapsed(timeout_ref))
 		if (bsec_status() & BSEC_MODE_PWR_MASK)
 			break;
@@ -238,14 +235,11 @@ static TEE_Result power_up_safmem(void)
 
 static TEE_Result power_down_safmem(void)
 {
-	uint64_t timeout_ref = timeout_init_us(BSEC_TIMEOUT_US);
+	uint64_t timeout_ref = 0;
 
 	io_mask32(bsec_base() + BSEC_OTP_CONF_OFF, 0, BSEC_CONF_POWER_UP_MASK);
 
-	/*
-	 * If a timeout is detected, test the condition again to consider
-	 * cases where timeout is due to the executing TEE thread rescheduling.
-	 */
+	timeout_ref = timeout_init_us(BSEC_TIMEOUT_US);
 	while (!timeout_elapsed(timeout_ref))
 		if (!(bsec_status() & BSEC_MODE_PWR_MASK))
 			break;