Commit 343d1919 authored by Jay Vasanth's avatar Jay Vasanth Committed by Anas Nashif
Browse files

uart: microchip: add low power & wake support 



changes to support low power and wake support in microchip xec uart
driver. Add support for wakerx_gpio config in dts to select the wake gpio.
Configure for wake in PM_DEVICE_ACTION_SUSPEND state and clear
interrupt in wake isr. Also added support for
CONFIG_UART_CONSOLE_INPUT_EXPIRED

Signed-off-by: default avatarJay Vasanth <jay.vasanth@microchip.com>
parent d3d80e8b

drivers/serial/uart_mchp_xec.c

+156 −1
Original line number Diff line number Diff line
@@ -30,9 +30,15 @@ 
#endif

#include <zephyr/drivers/pinctrl.h>

#include <zephyr/drivers/uart.h>

#include <zephyr/drivers/gpio.h>

#include <zephyr/sys/sys_io.h>

#include <zephyr/spinlock.h>

#include <zephyr/irq.h>

#include <zephyr/pm/device.h>

#include <zephyr/pm/policy.h>



#include <zephyr/logging/log.h>

LOG_MODULE_REGISTER(uart_xec, CONFIG_UART_LOG_LEVEL);



/* Clock source is 1.8432 MHz derived from PLL 48 MHz */

#define XEC_UART_CLK_SRC_1P8M		0
@@ -166,6 +172,12 @@ 


#define IIRC(dev) (((struct uart_xec_dev_data *)(dev)->data)->iir_cache)



enum uart_xec_pm_policy_state_flag {

	UART_XEC_PM_POLICY_STATE_TX_FLAG,

	UART_XEC_PM_POLICY_STATE_RX_FLAG,

	UART_XEC_PM_POLICY_STATE_FLAG_COUNT,

};



/* device config */

struct uart_xec_device_config {

	struct uart_regs *regs;
@@ -178,6 +190,10 @@ struct uart_xec_device_config { 
#if defined(CONFIG_UART_INTERRUPT_DRIVEN) || defined(CONFIG_UART_ASYNC_API)

	uart_irq_config_func_t	irq_config_func;

#endif

#ifdef CONFIG_PM_DEVICE

	struct gpio_dt_spec wakerx_gpio;

	bool wakeup_source;

#endif

};



/** Device data structure */
@@ -193,8 +209,32 @@ struct uart_xec_dev_data { 
#endif

};



#ifdef CONFIG_PM_DEVICE

	ATOMIC_DEFINE(pm_policy_state_flag, UART_XEC_PM_POLICY_STATE_FLAG_COUNT);

#endif



#if defined(CONFIG_PM_DEVICE) && defined(CONFIG_UART_CONSOLE_INPUT_EXPIRED)

	struct k_work_delayable rx_refresh_timeout_work;

#endif



static const struct uart_driver_api uart_xec_driver_api;



#ifdef CONFIG_PM_DEVICE

static void uart_xec_pm_policy_state_lock_get(enum uart_xec_pm_policy_state_flag flag)

{

	if (atomic_test_and_set_bit(pm_policy_state_flag, flag) == 0) {

		pm_policy_state_lock_get(PM_STATE_SUSPEND_TO_IDLE, PM_ALL_SUBSTATES);

	}

}



static void uart_xec_pm_policy_state_lock_put(enum uart_xec_pm_policy_state_flag flag)

{

	if (atomic_test_and_clear_bit(pm_policy_state_flag, flag) == 1) {

		pm_policy_state_lock_put(PM_STATE_SUSPEND_TO_IDLE, PM_ALL_SUBSTATES);

	}

}

#endif



#ifdef CONFIG_SOC_SERIES_MEC172X



static void uart_clr_slp_en(const struct device *dev)
@@ -398,6 +438,63 @@ static int uart_xec_config_get(const struct device *dev, 
}

#endif /* CONFIG_UART_USE_RUNTIME_CONFIGURE */



#ifdef CONFIG_PM_DEVICE



static void uart_xec_wake_handler(const struct device *gpio, struct gpio_callback *cb,

		   uint32_t pins)

{

	/* Disable interrupts on UART RX pin to avoid repeated interrupts. */

	(void)gpio_pin_interrupt_configure(gpio, (find_msb_set(pins) - 1),

					   GPIO_INT_DISABLE);

	/* Refresh console expired time */

#ifdef CONFIG_UART_CONSOLE_INPUT_EXPIRED

	k_timeout_t delay = K_MSEC(CONFIG_UART_CONSOLE_INPUT_EXPIRED_TIMEOUT);



	uart_xec_pm_policy_state_lock_get(UART_XEC_PM_POLICY_STATE_RX_FLAG);

	k_work_reschedule(&rx_refresh_timeout_work, delay);

#endif

}



static int uart_xec_pm_action(const struct device *dev,

					 enum pm_device_action action)

{

	const struct uart_xec_device_config * const dev_cfg = dev->config;

	struct uart_regs *regs = dev_cfg->regs;

	int ret = 0;



	switch (action) {

	case PM_DEVICE_ACTION_RESUME:

		regs->ACTV = MCHP_UART_LD_ACTIVATE;

		break;

	case PM_DEVICE_ACTION_SUSPEND:

		/* Enable UART wake interrupt */

		regs->ACTV = 0;

		if ((dev_cfg->wakeup_source) && (dev_cfg->wakerx_gpio.port != NULL)) {

			ret = gpio_pin_interrupt_configure_dt(&dev_cfg->wakerx_gpio,

						  GPIO_INT_MODE_EDGE | GPIO_INT_TRIG_LOW);

			if (ret < 0) {

				LOG_ERR("Failed to configure UART wake interrupt (ret %d)", ret);

				return ret;

			}

		}

		break;

	default:

		return -ENOTSUP;

	}



	return 0;

}



#ifdef CONFIG_UART_CONSOLE_INPUT_EXPIRED

static void uart_xec_rx_refresh_timeout(struct k_work *work)

{

	ARG_UNUSED(work);



	uart_xec_pm_policy_state_lock_put(UART_XEC_PM_POLICY_STATE_RX_FLAG);

}

#endif

#endif /* CONFIG_PM_DEVICE */



/**

 * @brief Initialize individual UART port

 *
@@ -429,6 +526,24 @@ static int uart_xec_init(const struct device *dev) 
	dev_cfg->irq_config_func(dev);

#endif



#ifdef CONFIG_PM_DEVICE

#ifdef CONFIG_UART_CONSOLE_INPUT_EXPIRED

		k_work_init_delayable(&rx_refresh_timeout_work, uart_xec_rx_refresh_timeout);

#endif

	if ((dev_cfg->wakeup_source) && (dev_cfg->wakerx_gpio.port != NULL)) {

		static struct gpio_callback uart_xec_wake_cb;



		gpio_init_callback(&uart_xec_wake_cb, uart_xec_wake_handler,

				   BIT(dev_cfg->wakerx_gpio.pin));



		ret = gpio_add_callback(dev_cfg->wakerx_gpio.port, &uart_xec_wake_cb);

		if (ret < 0) {

			LOG_ERR("Failed to add UART wake callback (err %d)", ret);

			return ret;

		}

	}

#endif



	return 0;

}
@@ -529,6 +644,9 @@ static int uart_xec_fifo_fill(const struct device *dev, const uint8_t *tx_data, 
	k_spinlock_key_t key = k_spin_lock(&dev_data->lock);



	for (i = 0; (i < size) && (regs->LSR & LSR_THRE) != 0; i++) {

#ifdef CONFIG_PM_DEVICE

		uart_xec_pm_policy_state_lock_get(UART_XEC_PM_POLICY_STATE_TX_FLAG);

#endif

		regs->RTXB = tx_data[i];

	}
@@ -797,11 +915,30 @@ static void uart_xec_irq_callback_set(const struct device *dev, 
static void uart_xec_isr(const struct device *dev)

{

	struct uart_xec_dev_data * const dev_data = dev->data;

#ifdef CONFIG_UART_CONSOLE_INPUT_EXPIRED

	const struct uart_xec_device_config * const dev_cfg = dev->config;

	struct uart_regs *regs = dev_cfg->regs;

	int rx_ready = 0;



	rx_ready = ((regs->LSR & LSR_RXRDY) == LSR_RXRDY) ? 1 : 0;

	if (rx_ready) {

		k_timeout_t delay = K_MSEC(CONFIG_UART_CONSOLE_INPUT_EXPIRED_TIMEOUT);



		uart_xec_pm_policy_state_lock_get(UART_XEC_PM_POLICY_STATE_RX_FLAG);

		k_work_reschedule(&rx_refresh_timeout_work, delay);

	}

#endif



	if (dev_data->cb) {

		dev_data->cb(dev, dev_data->cb_data);

	}



#ifdef CONFIG_PM_DEVICE

	if (uart_xec_irq_tx_complete(dev)) {

		uart_xec_pm_policy_state_lock_put(UART_XEC_PM_POLICY_STATE_TX_FLAG);

	}

#endif /* CONFIG_PM */



	/* clear ECIA GIRQ R/W1C status bit after UART status cleared */

	uart_xec_girq_clr(dev);

}
@@ -920,6 +1057,21 @@ static const struct uart_driver_api uart_xec_driver_api = { 
#define DEV_DATA_FLOW_CTRL(n)						\

	DT_INST_PROP_OR(n, hw_flow_control, UART_CFG_FLOW_CTRL_NONE)



/* To enable wakeup on the UART, the DTS needs to have two entries defined

 * in the corresponding UART node in the DTS specifying it as a wake source

 * and specifying the UART_RX GPIO; example as below

 *

 *	wakerx-gpios = <&gpio_140_176 25 GPIO_ACTIVE_HIGH>;

 *	wakeup-source;

 */

#ifdef CONFIG_PM_DEVICE

#define XEC_UART_PM_WAKEUP(n)						\

		.wakeup_source = (uint8_t)DT_INST_PROP_OR(n, wakeup_source, 0),	\

		.wakerx_gpio = GPIO_DT_SPEC_INST_GET_OR(n, wakerx_gpios, {0}),

#else

#define XEC_UART_PM_WAKEUP(index) /* Not used */

#endif



#define UART_XEC_DEVICE_INIT(n)						\

									\

	PINCTRL_DT_INST_DEFINE(n);					\
@@ -934,6 +1086,7 @@ static const struct uart_driver_api uart_xec_driver_api = { 
		.pcr_idx = DT_INST_PROP_BY_IDX(n, pcrs, 0),		\

		.pcr_bitpos = DT_INST_PROP_BY_IDX(n, pcrs, 1),		\

		.pcfg = PINCTRL_DT_INST_DEV_CONFIG_GET(n),		\

		XEC_UART_PM_WAKEUP(n)	\

		DEV_CONFIG_IRQ_FUNC_INIT(n)				\

	};								\

	static struct uart_xec_dev_data uart_xec_dev_data_##n = {	\
@@ -943,7 +1096,9 @@ static const struct uart_driver_api uart_xec_driver_api = { 
		.uart_config.data_bits = UART_CFG_DATA_BITS_8,		\

		.uart_config.flow_ctrl = DEV_DATA_FLOW_CTRL(n),		\

	};								\

	DEVICE_DT_INST_DEFINE(n, &uart_xec_init, NULL,			\

	PM_DEVICE_DT_INST_DEFINE(n, uart_xec_pm_action);		\

	DEVICE_DT_INST_DEFINE(n, &uart_xec_init,			\

			      PM_DEVICE_DT_INST_GET(n),			\

			      &uart_xec_dev_data_##n,			\

			      &uart_xec_dev_cfg_##n,			\

			      PRE_KERNEL_1,				\

dts/bindings/serial/microchip,xec-uart.yaml

+4 −0
Original line number Diff line number Diff line
@@ -31,3 +31,7 @@ properties: 


  pinctrl-names:

    required: true



  wakerx-gpios:

    type: phandle-array

    description: GPIO configured as UART RX wake source

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