drivers: bluetooth: hci: Add PM support to the STM32WB0x HCI driver

Add PM support to the STM32WB0x Bluetooth HCI driver.

Implement PM event register to wake up the device for its BLE events.

Signed-off-by: Ali Hozhabri <[email protected]>

Author: HoZHel

drivers/bluetooth/hci/hci_stm32wb0.c

@@ -11,6 +11,8 @@
 #include <zephyr/bluetooth/hci_types.h>
 #include <zephyr/drivers/bluetooth.h>
 #include <zephyr/drivers/entropy.h>
+#include <zephyr/pm/policy.h>
+#include <zephyr/pm/device.h>
 #include "bleplat_cntr.h"
 #include "ble_stack.h"
 #include "stm32wb0x_hal_radio_timer.h"
@@ -49,10 +51,30 @@ LOG_MODULE_REGISTER(bt_driver);
 #define EVT_VENDOR_CODE_LSB  3
 #define EVT_VENDOR_CODE_MSB  4
 
+#if (defined(CONFIG_SOC_STM32WB06) || defined(CONFIG_SOC_STM32WB07)) && defined(CONFIG_PM)
+#error "At the moment, PM is not supported for WB06 & WB07"
+#endif /* (CONFIG_SOC_STM32WB06 || CONFIG_SOC_STM32WB07) && CONFIG_PM */
+
 static uint32_t __noinit dyn_alloc_a[BLE_DYN_ALLOC_SIZE >> 2];
 static uint8_t buffer_out_mem[MAX_EVENT_SIZE];
 static struct k_work_delayable ble_stack_work;
 
+#if CONFIG_PM_DEVICE
+/* ST Proprietary extended event */
+#define HCI_EXT_EVT					0x82
+#define ACI_HAL_END_OF_RADIO_ACTIVITY_VSEVT_CODE	0x0004
+#define STATE_ALL_BITMASK				0xFFFF
+#define STATE_IDLE					0x00
+struct bt_hci_ext_evt_hdr {
+	uint8_t type;
+	uint8_t evt;
+	uint16_t len;
+	uint16_t vs_code;
+	uint8_t last_state;
+	uint8_t next_state;
+} __packed;
+#endif /* CONFIG_PM_DEVICE */
+
 static struct net_buf *get_rx(uint8_t *msg);
 static PKA_HandleTypeDef hpka;
 
@@ -70,11 +92,40 @@ int BLEPLAT_NvmGet(void)
 	return 0;
 }
 
+#if CONFIG_PM_DEVICE
+/* Inform Zephyr PM about wakeup event from radio */
+static void register_radio_event(uint32_t time, bool unregister)
+{
+	int64_t value_ms, ticks;
+	static struct pm_policy_event radio_evt;
+	static bool first_time = true;
+
+	if (unregister) {
+		if (!first_time) {
+			first_time = true;
+			pm_policy_event_unregister(&radio_evt);
+		}
+	} else {
+		value_ms = HAL_RADIO_TIMER_DiffSysTimeMs(time, HAL_RADIO_TIMER_GetCurrentSysTime());
+		ticks = k_ms_to_ticks_floor64(value_ms) + k_uptime_ticks();
+		if (first_time) {
+			pm_policy_event_register(&radio_evt, ticks);
+			first_time = false;
+		} else {
+			pm_policy_event_update(&radio_evt, ticks);
+		}
+	}
+}
+#endif /* CONFIG_PM_DEVICE */
+
 uint8_t BLEPLAT_SetRadioTimerValue(uint32_t Time, uint8_t EventType, uint8_t CalReq)
 {
 	uint8_t retval;
 
 	retval = HAL_RADIO_TIMER_SetRadioTimerValue(Time, EventType, CalReq);
+#if CONFIG_PM_DEVICE
+	register_radio_event(Time, false);
+#endif /* CONFIG_PM_DEVICE */
 	return retval;
 }
 
@@ -192,9 +243,24 @@ void send_event(uint8_t *buffer_out, uint16_t buffer_out_length, int8_t overflow
 
 	const struct device *dev = DEVICE_DT_GET(DT_DRV_INST(0));
 	struct hci_data *hci = dev->data;
-	/* Construct net_buf from event data */
-	struct net_buf *buf = get_rx(buffer_out);
+	struct net_buf *buf;
 
+#if CONFIG_PM_DEVICE
+	struct bt_hci_ext_evt_hdr *vs_evt = (struct bt_hci_ext_evt_hdr *)(buffer_out);
+
+	if (vs_evt->type == HCI_EXT_EVT) {
+		if (vs_evt->evt == BT_HCI_EVT_VENDOR) {
+			if ((vs_evt->vs_code == ACI_HAL_END_OF_RADIO_ACTIVITY_VSEVT_CODE) &&
+			    (vs_evt->next_state == STATE_IDLE)) {
+				register_radio_event(0, true);
+			}
+			return;
+		}
+	}
+#endif /* CONFIG_PM_DEVICE */
+
+	/* Construct net_buf from event data */
+	buf = get_rx(buffer_out);
 	if (buf) {
 		/* Handle the received HCI data */
 		LOG_DBG("New event %p len %u type %u", buf, buf->len, buf->data[0]);
@@ -250,6 +316,36 @@ static void ble_isr_installer(void)
 	IRQ_CONNECT(PKA_IRQn, PKA_PRIO, _PKA_IRQHandler, NULL, PKA_FLAGS);
 }
 
+#if defined(CONFIG_PM_DEVICE)
+static int ble_pm_action(const struct device *dev,
+			 enum pm_device_action action)
+{
+	static uint32_t PKA_CR_vr;
+
+	switch (action) {
+	case PM_DEVICE_ACTION_SUSPEND:
+		LL_PWR_EnableWU_EWBLE();
+		PKA_CR_vr = PKA->CR;
+		/* TBD: Manage PKA save for WB06 & WB07 */
+		break;
+	case PM_DEVICE_ACTION_RESUME:
+		LL_PWR_DisableWU_EWBLE();
+		/* TBD: Manage PKA restore for WB06 & WB07 */
+		PKA->CLRFR = PKA_CLRFR_PROCENDFC | PKA_CLRFR_RAMERRFC | PKA_CLRFR_ADDRERRFC;
+		PKA->CR = PKA_CR_vr;
+		ble_isr_installer();
+		irq_enable(RADIO_TXRX_IRQn);
+		irq_enable(RADIO_TXRX_SEQ_IRQn);
+		irq_enable(PKA_IRQn);
+		break;
+	default:
+		return -ENOTSUP;
+	}
+
+	return 0;
+}
+#endif /* CONFIG_PM_DEVICE */
+
 static void rng_get_random(void *num, size_t size)
 {
 	const struct device *dev = DEVICE_DT_GET(DT_DRV_INST(0));
@@ -449,7 +545,9 @@ static int bt_hci_stm32wb0_open(const struct device *dev, bt_hci_recv_t recv)
 #endif /* CONFIG_BT_EXT_ADV */
 
 	aci_adv_nwk_init();
-
+#if CONFIG_PM_DEVICE
+	aci_hal_set_radio_activity_mask(STATE_ALL_BITMASK);
+#endif /* CONFIG_PM_DEVICE */
 	data->recv = recv;
 	k_work_init_delayable(&ble_stack_work, blestack_process);
 	k_work_schedule(&ble_stack_work, K_NO_WAIT);
@@ -462,10 +560,12 @@ static DEVICE_API(bt_hci, drv) = {
 	.send = bt_hci_stm32wb0_send,
 };
 
+PM_DEVICE_DT_INST_DEFINE(0, ble_pm_action);
+
 #define HCI_DEVICE_INIT(inst) \
 	static struct hci_data hci_data_##inst = { \
 	}; \
-	DEVICE_DT_INST_DEFINE(inst, NULL, NULL, &hci_data_##inst, NULL, \
+	DEVICE_DT_INST_DEFINE(inst, NULL, PM_DEVICE_DT_INST_GET(0), &hci_data_##inst, NULL, \
 				POST_KERNEL, CONFIG_KERNEL_INIT_PRIORITY_DEVICE, &drv)
 
 /* Only one instance supported */