[linux-block.git] / drivers / net / ipa / ipa_power.c

// SPDX-License-Identifier: GPL-2.0

/* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
 * Copyright (C) 2018-2021 Linaro Ltd.
 */

#include <linux/clk.h>
#include <linux/device.h>
#include <linux/interconnect.h>
#include <linux/pm.h>
#include <linux/pm_runtime.h>
#include <linux/bitops.h>

#include "linux/soc/qcom/qcom_aoss.h"

#include "ipa.h"
#include "ipa_power.h"
#include "ipa_endpoint.h"
#include "ipa_modem.h"
#include "ipa_data.h"

/**
 * DOC: IPA Power Management
 *
 * The IPA hardware is enabled when the IPA core clock and all the
 * interconnects (buses) it depends on are enabled.  Runtime power
 * management is used to determine whether the core clock and
 * interconnects are enabled, and if not in use to be suspended
 * automatically.
 *
 * The core clock currently runs at a fixed clock rate when enabled,
 * an all interconnects use a fixed average and peak bandwidth.
 */

#define IPA_AUTOSUSPEND_DELAY	500	/* milliseconds */

/**
 * enum ipa_power_flag - IPA power flags
 * @IPA_POWER_FLAG_RESUMED:	Whether resume from suspend has been signaled
 * @IPA_POWER_FLAG_SYSTEM:	Hardware is system (not runtime) suspended
 * @IPA_POWER_FLAG_STOPPED:	Modem TX is disabled by ipa_start_xmit()
 * @IPA_POWER_FLAG_STARTED:	Modem TX was enabled by ipa_runtime_resume()
 * @IPA_POWER_FLAG_COUNT:	Number of defined power flags
 */
enum ipa_power_flag {
	IPA_POWER_FLAG_RESUMED,
	IPA_POWER_FLAG_SYSTEM,
	IPA_POWER_FLAG_STOPPED,
	IPA_POWER_FLAG_STARTED,
	IPA_POWER_FLAG_COUNT,		/* Last; not a flag */
};

/**
 * struct ipa_power - IPA power management information
 * @dev:		IPA device pointer
 * @core:		IPA core clock
 * @qmp:		QMP handle for AOSS communication
 * @spinlock:		Protects modem TX queue enable/disable
 * @flags:		Boolean state flags
 * @interconnect_count:	Number of elements in interconnect[]
 * @interconnect:	Interconnect array
 */
struct ipa_power {
	struct device *dev;
	struct clk *core;
	struct qmp *qmp;
	spinlock_t spinlock;	/* used with STOPPED/STARTED power flags */
	DECLARE_BITMAP(flags, IPA_POWER_FLAG_COUNT);
	u32 interconnect_count;
	struct icc_bulk_data interconnect[];
};

/* Initialize interconnects required for IPA operation */
static int ipa_interconnect_init(struct ipa_power *power,
				 const struct ipa_interconnect_data *data)
{
	struct icc_bulk_data *interconnect;
	int ret;
	u32 i;

	/* Initialize our interconnect data array for bulk operations */
	interconnect = &power->interconnect[0];
	for (i = 0; i < power->interconnect_count; i++) {
		/* interconnect->path is filled in by of_icc_bulk_get() */
		interconnect->name = data->name;
		interconnect->avg_bw = data->average_bandwidth;
		interconnect->peak_bw = data->peak_bandwidth;
		data++;
		interconnect++;
	}

	ret = of_icc_bulk_get(power->dev, power->interconnect_count,
			      power->interconnect);
	if (ret)
		return ret;

	/* All interconnects are initially disabled */
	icc_bulk_disable(power->interconnect_count, power->interconnect);

	/* Set the bandwidth values to be used when enabled */
	ret = icc_bulk_set_bw(power->interconnect_count, power->interconnect);
	if (ret)
		icc_bulk_put(power->interconnect_count, power->interconnect);

	return ret;
}

/* Inverse of ipa_interconnect_init() */
static void ipa_interconnect_exit(struct ipa_power *power)
{
	icc_bulk_put(power->interconnect_count, power->interconnect);
}

/* Enable IPA power, enabling interconnects and the core clock */
static int ipa_power_enable(struct ipa *ipa)
{
	struct ipa_power *power = ipa->power;
	int ret;

	ret = icc_bulk_enable(power->interconnect_count, power->interconnect);
	if (ret)
		return ret;

	ret = clk_prepare_enable(power->core);
	if (ret) {
		dev_err(power->dev, "error %d enabling core clock\n", ret);
		icc_bulk_disable(power->interconnect_count,
				 power->interconnect);
	}

	return ret;
}

/* Inverse of ipa_power_enable() */
static void ipa_power_disable(struct ipa *ipa)
{
	struct ipa_power *power = ipa->power;

	clk_disable_unprepare(power->core);

	icc_bulk_disable(power->interconnect_count, power->interconnect);
}

static int ipa_runtime_suspend(struct device *dev)
{
	struct ipa *ipa = dev_get_drvdata(dev);

	/* Endpoints aren't usable until setup is complete */
	if (ipa->setup_complete) {
		__clear_bit(IPA_POWER_FLAG_RESUMED, ipa->power->flags);
		ipa_endpoint_suspend(ipa);
		gsi_suspend(&ipa->gsi);
	}

	ipa_power_disable(ipa);

	return 0;
}

static int ipa_runtime_resume(struct device *dev)
{
	struct ipa *ipa = dev_get_drvdata(dev);
	int ret;

	ret = ipa_power_enable(ipa);
	if (WARN_ON(ret < 0))
		return ret;

	/* Endpoints aren't usable until setup is complete */
	if (ipa->setup_complete) {
		gsi_resume(&ipa->gsi);
		ipa_endpoint_resume(ipa);
	}

	return 0;
}

static int ipa_suspend(struct device *dev)
{
	struct ipa *ipa = dev_get_drvdata(dev);

	__set_bit(IPA_POWER_FLAG_SYSTEM, ipa->power->flags);

	return pm_runtime_force_suspend(dev);
}

static int ipa_resume(struct device *dev)
{
	struct ipa *ipa = dev_get_drvdata(dev);
	int ret;

	ret = pm_runtime_force_resume(dev);

	__clear_bit(IPA_POWER_FLAG_SYSTEM, ipa->power->flags);

	return ret;
}

/* Return the current IPA core clock rate */
u32 ipa_core_clock_rate(struct ipa *ipa)
{
	return ipa->power ? (u32)clk_get_rate(ipa->power->core) : 0;
}

/**
 * ipa_suspend_handler() - Handle the suspend IPA interrupt
 * @ipa:	IPA pointer
 * @irq_id:	IPA interrupt type (unused)
 *
 * If an RX endpoint is suspended, and the IPA has a packet destined for
 * that endpoint, the IPA generates a SUSPEND interrupt to inform the AP
 * that it should resume the endpoint.  If we get one of these interrupts
 * we just wake up the system.
 */
static void ipa_suspend_handler(struct ipa *ipa, enum ipa_irq_id irq_id)
{
	/* To handle an IPA interrupt we will have resumed the hardware
	 * just to handle the interrupt, so we're done.  If we are in a
	 * system suspend, trigger a system resume.
	 */
	if (!__test_and_set_bit(IPA_POWER_FLAG_RESUMED, ipa->power->flags))
		if (test_bit(IPA_POWER_FLAG_SYSTEM, ipa->power->flags))
			pm_wakeup_dev_event(&ipa->pdev->dev, 0, true);

	/* Acknowledge/clear the suspend interrupt on all endpoints */
	ipa_interrupt_suspend_clear_all(ipa->interrupt);
}

/* The next few functions coordinate stopping and starting the modem
 * network device transmit queue.
 *
 * Transmit can be running concurrent with power resume, and there's a
 * chance the resume completes before the transmit path stops the queue,
 * leaving the queue in a stopped state.  The next two functions are used
 * to avoid this: ipa_power_modem_queue_stop() is used by ipa_start_xmit()
 * to conditionally stop the TX queue; and ipa_power_modem_queue_start()
 * is used by ipa_runtime_resume() to conditionally restart it.
 *
 * Two flags and a spinlock are used.  If the queue is stopped, the STOPPED
 * power flag is set.  And if the queue is started, the STARTED flag is set.
 * The queue is only started on resume if the STOPPED flag is set.  And the
 * queue is only started in ipa_start_xmit() if the STARTED flag is *not*
 * set.  As a result, the queue remains operational if the two activites
 * happen concurrently regardless of the order they complete.  The spinlock
 * ensures the flag and TX queue operations are done atomically.
 *
 * The first function stops the modem netdev transmit queue, but only if
 * the STARTED flag is *not* set.  That flag is cleared if it was set.
 * If the queue is stopped, the STOPPED flag is set.  This is called only
 * from the power ->runtime_resume operation.
 */
void ipa_power_modem_queue_stop(struct ipa *ipa)
{
	struct ipa_power *power = ipa->power;
	unsigned long flags;

	spin_lock_irqsave(&power->spinlock, flags);

	if (!__test_and_clear_bit(IPA_POWER_FLAG_STARTED, power->flags)) {
		netif_stop_queue(ipa->modem_netdev);
		__set_bit(IPA_POWER_FLAG_STOPPED, power->flags);
	}

	spin_unlock_irqrestore(&power->spinlock, flags);
}

/* This function starts the modem netdev transmit queue, but only if the
 * STOPPED flag is set.  That flag is cleared if it was set.  If the queue
 * was restarted, the STARTED flag is set; this allows ipa_start_xmit()
 * to skip stopping the queue in the event of a race.
 */
void ipa_power_modem_queue_wake(struct ipa *ipa)
{
	struct ipa_power *power = ipa->power;
	unsigned long flags;

	spin_lock_irqsave(&power->spinlock, flags);

	if (__test_and_clear_bit(IPA_POWER_FLAG_STOPPED, power->flags)) {
		__set_bit(IPA_POWER_FLAG_STARTED, power->flags);
		netif_wake_queue(ipa->modem_netdev);
	}

	spin_unlock_irqrestore(&power->spinlock, flags);
}

/* This function clears the STARTED flag once the TX queue is operating */
void ipa_power_modem_queue_active(struct ipa *ipa)
{
	clear_bit(IPA_POWER_FLAG_STARTED, ipa->power->flags);
}

static int ipa_power_retention_init(struct ipa_power *power)
{
	struct qmp *qmp = qmp_get(power->dev);

	if (IS_ERR(qmp)) {
		if (PTR_ERR(qmp) == -EPROBE_DEFER)
			return -EPROBE_DEFER;

		/* We assume any other error means it's not defined/needed */
		qmp = NULL;
	}
	power->qmp = qmp;

	return 0;
}

static void ipa_power_retention_exit(struct ipa_power *power)
{
	qmp_put(power->qmp);
	power->qmp = NULL;
}

/* Control register retention on power collapse */
void ipa_power_retention(struct ipa *ipa, bool enable)
{
	static const char fmt[] = "{ class: bcm, res: ipa_pc, val: %c }";
	struct ipa_power *power = ipa->power;
	char buf[36];	/* Exactly enough for fmt[]; size a multiple of 4 */
	int ret;

	if (!power->qmp)
		return;		/* Not needed on this platform */

	(void)snprintf(buf, sizeof(buf), fmt, enable ? '1' : '0');

	ret = qmp_send(power->qmp, buf, sizeof(buf));
	if (ret)
		dev_err(power->dev, "error %d sending QMP %sable request\n",
			ret, enable ? "en" : "dis");
}

int ipa_power_setup(struct ipa *ipa)
{
	int ret;

	ipa_interrupt_add(ipa->interrupt, IPA_IRQ_TX_SUSPEND,
			  ipa_suspend_handler);

	ret = device_init_wakeup(&ipa->pdev->dev, true);
	if (ret)
		ipa_interrupt_remove(ipa->interrupt, IPA_IRQ_TX_SUSPEND);

	return ret;
}

void ipa_power_teardown(struct ipa *ipa)
{
	(void)device_init_wakeup(&ipa->pdev->dev, false);
	ipa_interrupt_remove(ipa->interrupt, IPA_IRQ_TX_SUSPEND);
}

/* Initialize IPA power management */
struct ipa_power *
ipa_power_init(struct device *dev, const struct ipa_power_data *data)
{
	struct ipa_power *power;
	struct clk *clk;
	size_t size;
	int ret;

	clk = clk_get(dev, "core");
	if (IS_ERR(clk)) {
		dev_err_probe(dev, PTR_ERR(clk), "error getting core clock\n");

		return ERR_CAST(clk);
	}

	ret = clk_set_rate(clk, data->core_clock_rate);
	if (ret) {
		dev_err(dev, "error %d setting core clock rate to %u\n",
			ret, data->core_clock_rate);
		goto err_clk_put;
	}

	size = struct_size(power, interconnect, data->interconnect_count);
	power = kzalloc(size, GFP_KERNEL);
	if (!power) {
		ret = -ENOMEM;
		goto err_clk_put;
	}
	power->dev = dev;
	power->core = clk;
	spin_lock_init(&power->spinlock);
	power->interconnect_count = data->interconnect_count;

	ret = ipa_interconnect_init(power, data->interconnect_data);
	if (ret)
		goto err_kfree;

	ret = ipa_power_retention_init(power);
	if (ret)
		goto err_interconnect_exit;

	pm_runtime_set_autosuspend_delay(dev, IPA_AUTOSUSPEND_DELAY);
	pm_runtime_use_autosuspend(dev);
	pm_runtime_enable(dev);

	return power;

err_interconnect_exit:
	ipa_interconnect_exit(power);
err_kfree:
	kfree(power);
err_clk_put:
	clk_put(clk);

	return ERR_PTR(ret);
}

/* Inverse of ipa_power_init() */
void ipa_power_exit(struct ipa_power *power)
{
	struct device *dev = power->dev;
	struct clk *clk = power->core;

	pm_runtime_disable(dev);
	pm_runtime_dont_use_autosuspend(dev);
	ipa_power_retention_exit(power);
	ipa_interconnect_exit(power);
	kfree(power);
	clk_put(clk);
}

const struct dev_pm_ops ipa_pm_ops = {
	.suspend		= ipa_suspend,
	.resume			= ipa_resume,
	.runtime_suspend	= ipa_runtime_suspend,
	.runtime_resume		= ipa_runtime_resume,
};
Commit	Line	Data
ba764c4d AE	1	// SPDX-License-Identifier: GPL-2.0
	2
	3	/* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
4c7ccfcd	4	* Copyright (C) 2018-2021 Linaro Ltd.
ba764c4d AE	5	*/
ba764c4d AE	6
ba764c4d AE	7	#include <linux/clk.h>
	8	#include <linux/device.h>
	9	#include <linux/interconnect.h>
73ff316d	10	#include <linux/pm.h>
2abb0c7f	11	#include <linux/pm_runtime.h>
73ff316d	12	#include <linux/bitops.h>
ba764c4d	13
34a08176 AE	14	#include "linux/soc/qcom/qcom_aoss.h"
34a08176 AE	15
ba764c4d	16	#include "ipa.h"
2775cbc5	17	#include "ipa_power.h"
73ff316d	18	#include "ipa_endpoint.h"
ba764c4d	19	#include "ipa_modem.h"
dfccb8b1	20	#include "ipa_data.h"
ba764c4d AE	21
ba764c4d AE	22	/**
7aa0e8b8	23	* DOC: IPA Power Management
ba764c4d	24	*
7aa0e8b8 AE	25	* The IPA hardware is enabled when the IPA core clock and all the
	26	* interconnects (buses) it depends on are enabled. Runtime power
	27	* management is used to determine whether the core clock and
	28	* interconnects are enabled, and if not in use to be suspended
	29	* automatically.
ba764c4d	30	*
7aa0e8b8 AE	31	* The core clock currently runs at a fixed clock rate when enabled,
7aa0e8b8 AE	32	* an all interconnects use a fixed average and peak bandwidth.
ba764c4d AE	33	*/
ba764c4d AE	34
1aac309d AE	35	#define IPA_AUTOSUSPEND_DELAY 500 /* milliseconds */
1aac309d AE	36
afb08b7e AE	37	/**
	38	* enum ipa_power_flag - IPA power flags
	39	* @IPA_POWER_FLAG_RESUMED: Whether resume from suspend has been signaled
b9c532c1	40	* @IPA_POWER_FLAG_SYSTEM: Hardware is system (not runtime) suspended
b8e36e13 AE	41	* @IPA_POWER_FLAG_STOPPED: Modem TX is disabled by ipa_start_xmit()
b8e36e13 AE	42	* @IPA_POWER_FLAG_STARTED: Modem TX was enabled by ipa_runtime_resume()
afb08b7e AE	43	* @IPA_POWER_FLAG_COUNT: Number of defined power flags
	44	*/
	45	enum ipa_power_flag {
	46	IPA_POWER_FLAG_RESUMED,
b9c532c1	47	IPA_POWER_FLAG_SYSTEM,
b8e36e13 AE	48	IPA_POWER_FLAG_STOPPED,
b8e36e13 AE	49	IPA_POWER_FLAG_STARTED,
afb08b7e AE	50	IPA_POWER_FLAG_COUNT, /* Last; not a flag */
	51	};
	52
ba764c4d	53	/**
7aa0e8b8	54	* struct ipa_power - IPA power management information
63de79f0	55	* @dev: IPA device pointer
ba764c4d	56	* @core: IPA core clock
34a08176	57	* @qmp: QMP handle for AOSS communication
b8e36e13	58	* @spinlock: Protects modem TX queue enable/disable
afb08b7e	59	* @flags: Boolean state flags
ea151e19	60	* @interconnect_count: Number of elements in interconnect[]
5b40810b	61	* @interconnect: Interconnect array
ba764c4d	62	*/
7aa0e8b8	63	struct ipa_power {
63de79f0	64	struct device *dev;
ba764c4d	65	struct clk *core;
34a08176	66	struct qmp *qmp;
b8e36e13	67	spinlock_t spinlock; /* used with STOPPED/STARTED power flags */
afb08b7e	68	DECLARE_BITMAP(flags, IPA_POWER_FLAG_COUNT);
ea151e19	69	u32 interconnect_count;
8ee7ec48	70	struct icc_bulk_data interconnect[];
ba764c4d AE	71	};
ba764c4d AE	72
ba764c4d	73	/* Initialize interconnects required for IPA operation */
37e0cf33	74	static int ipa_interconnect_init(struct ipa_power *power,
db6cd514	75	const struct ipa_interconnect_data *data)
ba764c4d	76	{
c7be12fa	77	struct icc_bulk_data *interconnect;
10d0d397	78	int ret;
8ee7ec48	79	u32 i;
ea151e19	80
63ac8cce	81	/* Initialize our interconnect data array for bulk operations */
8ee7ec48 AE	82	interconnect = &power->interconnect[0];
8ee7ec48 AE	83	for (i = 0; i < power->interconnect_count; i++) {
63ac8cce AE	84	/* interconnect->path is filled in by of_icc_bulk_get() */
	85	interconnect->name = data->name;
	86	interconnect->avg_bw = data->average_bandwidth;
	87	interconnect->peak_bw = data->peak_bandwidth;
	88	data++;
ea151e19 AE	89	interconnect++;
ea151e19 AE	90	}
ba764c4d	91
37e0cf33	92	ret = of_icc_bulk_get(power->dev, power->interconnect_count,
63ac8cce AE	93	power->interconnect);
63ac8cce AE	94	if (ret)
8ee7ec48	95	return ret;
63ac8cce AE	96
	97	/* All interconnects are initially disabled */
	98	icc_bulk_disable(power->interconnect_count, power->interconnect);
	99
	100	/* Set the bandwidth values to be used when enabled */
	101	ret = icc_bulk_set_bw(power->interconnect_count, power->interconnect);
	102	if (ret)
8ee7ec48	103	icc_bulk_put(power->interconnect_count, power->interconnect);
10d0d397 AE	104
10d0d397 AE	105	return ret;
ba764c4d AE	106	}
	107
	108	/* Inverse of ipa_interconnect_init() */
7aa0e8b8	109	static void ipa_interconnect_exit(struct ipa_power *power)
ba764c4d	110	{
63ac8cce	111	icc_bulk_put(power->interconnect_count, power->interconnect);
ba764c4d AE	112	}
ba764c4d AE	113
7aa0e8b8 AE	114	/* Enable IPA power, enabling interconnects and the core clock */
7aa0e8b8 AE	115	static int ipa_power_enable(struct ipa *ipa)
ba764c4d	116	{
90078e63	117	struct ipa_power *power = ipa->power;
ba764c4d AE	118	int ret;
ba764c4d AE	119
90078e63	120	ret = icc_bulk_enable(power->interconnect_count, power->interconnect);
ba764c4d AE	121	if (ret)
	122	return ret;
	123
90078e63	124	ret = clk_prepare_enable(power->core);
8ee7c40a	125	if (ret) {
37e0cf33	126	dev_err(power->dev, "error %d enabling core clock\n", ret);
90078e63 AE	127	icc_bulk_disable(power->interconnect_count,
90078e63 AE	128	power->interconnect);
8ee7c40a	129	}
ba764c4d AE	130
	131	return ret;
	132	}
	133
7aa0e8b8	134	/* Inverse of ipa_power_enable() */
90078e63	135	static void ipa_power_disable(struct ipa *ipa)
ba764c4d	136	{
90078e63 AE	137	struct ipa_power *power = ipa->power;
	138
	139	clk_disable_unprepare(power->core);
7ebd168c	140
90078e63	141	icc_bulk_disable(power->interconnect_count, power->interconnect);
ba764c4d AE	142	}
ba764c4d AE	143
2abb0c7f AE	144	static int ipa_runtime_suspend(struct device *dev)
	145	{
	146	struct ipa *ipa = dev_get_drvdata(dev);
	147
	148	/* Endpoints aren't usable until setup is complete */
	149	if (ipa->setup_complete) {
7aa0e8b8	150	__clear_bit(IPA_POWER_FLAG_RESUMED, ipa->power->flags);
2abb0c7f AE	151	ipa_endpoint_suspend(ipa);
	152	gsi_suspend(&ipa->gsi);
	153	}
	154
90078e63 AE	155	ipa_power_disable(ipa);
	156
	157	return 0;
2abb0c7f AE	158	}
	159
	160	static int ipa_runtime_resume(struct device *dev)
	161	{
	162	struct ipa *ipa = dev_get_drvdata(dev);
	163	int ret;
	164
7aa0e8b8	165	ret = ipa_power_enable(ipa);
2abb0c7f AE	166	if (WARN_ON(ret < 0))
	167	return ret;
	168
	169	/* Endpoints aren't usable until setup is complete */
	170	if (ipa->setup_complete) {
	171	gsi_resume(&ipa->gsi);
	172	ipa_endpoint_resume(ipa);
	173	}
	174
	175	return 0;
	176	}
	177
b9c532c1 AE	178	static int ipa_suspend(struct device *dev)
	179	{
	180	struct ipa *ipa = dev_get_drvdata(dev);
	181
7aa0e8b8	182	__set_bit(IPA_POWER_FLAG_SYSTEM, ipa->power->flags);
b9c532c1 AE	183
	184	return pm_runtime_force_suspend(dev);
	185	}
	186
	187	static int ipa_resume(struct device *dev)
	188	{
	189	struct ipa *ipa = dev_get_drvdata(dev);
	190	int ret;
	191
	192	ret = pm_runtime_force_resume(dev);
	193
7aa0e8b8	194	__clear_bit(IPA_POWER_FLAG_SYSTEM, ipa->power->flags);
b9c532c1 AE	195
	196	return ret;
	197	}
	198
78b348f3	199	/* Return the current IPA core clock rate */
7aa0e8b8	200	u32 ipa_core_clock_rate(struct ipa *ipa)
78b348f3	201	{
7aa0e8b8	202	return ipa->power ? (u32)clk_get_rate(ipa->power->core) : 0;
78b348f3 AE	203	}
78b348f3 AE	204
afe1baa8 AE	205	/**
	206	* ipa_suspend_handler() - Handle the suspend IPA interrupt
	207	* @ipa: IPA pointer
	208	* @irq_id: IPA interrupt type (unused)
	209	*
	210	* If an RX endpoint is suspended, and the IPA has a packet destined for
	211	* that endpoint, the IPA generates a SUSPEND interrupt to inform the AP
	212	* that it should resume the endpoint. If we get one of these interrupts
	213	* we just wake up the system.
	214	*/
	215	static void ipa_suspend_handler(struct ipa *ipa, enum ipa_irq_id irq_id)
	216	{
b9c532c1 AE	217	/* To handle an IPA interrupt we will have resumed the hardware
	218	* just to handle the interrupt, so we're done. If we are in a
	219	* system suspend, trigger a system resume.
afe1baa8	220	*/
7aa0e8b8 AE	221	if (!__test_and_set_bit(IPA_POWER_FLAG_RESUMED, ipa->power->flags))
7aa0e8b8 AE	222	if (test_bit(IPA_POWER_FLAG_SYSTEM, ipa->power->flags))
b9c532c1	223	pm_wakeup_dev_event(&ipa->pdev->dev, 0, true);
afe1baa8 AE	224
	225	/* Acknowledge/clear the suspend interrupt on all endpoints */
	226	ipa_interrupt_suspend_clear_all(ipa->interrupt);
	227	}
	228
b8e36e13 AE	229	/* The next few functions coordinate stopping and starting the modem
	230	* network device transmit queue.
	231	*
	232	* Transmit can be running concurrent with power resume, and there's a
	233	* chance the resume completes before the transmit path stops the queue,
	234	* leaving the queue in a stopped state. The next two functions are used
	235	* to avoid this: ipa_power_modem_queue_stop() is used by ipa_start_xmit()
	236	* to conditionally stop the TX queue; and ipa_power_modem_queue_start()
	237	* is used by ipa_runtime_resume() to conditionally restart it.
	238	*
	239	* Two flags and a spinlock are used. If the queue is stopped, the STOPPED
	240	* power flag is set. And if the queue is started, the STARTED flag is set.
	241	* The queue is only started on resume if the STOPPED flag is set. And the
	242	* queue is only started in ipa_start_xmit() if the STARTED flag is not
	243	* set. As a result, the queue remains operational if the two activites
	244	* happen concurrently regardless of the order they complete. The spinlock
	245	* ensures the flag and TX queue operations are done atomically.
	246	*
	247	* The first function stops the modem netdev transmit queue, but only if
	248	* the STARTED flag is not set. That flag is cleared if it was set.
	249	* If the queue is stopped, the STOPPED flag is set. This is called only
	250	* from the power ->runtime_resume operation.
	251	*/
	252	void ipa_power_modem_queue_stop(struct ipa *ipa)
	253	{
7aa0e8b8	254	struct ipa_power *power = ipa->power;
b8e36e13 AE	255	unsigned long flags;
b8e36e13 AE	256
7aa0e8b8	257	spin_lock_irqsave(&power->spinlock, flags);
b8e36e13	258
7aa0e8b8	259	if (!__test_and_clear_bit(IPA_POWER_FLAG_STARTED, power->flags)) {
b8e36e13	260	netif_stop_queue(ipa->modem_netdev);
7aa0e8b8	261	__set_bit(IPA_POWER_FLAG_STOPPED, power->flags);
b8e36e13 AE	262	}
b8e36e13 AE	263
7aa0e8b8	264	spin_unlock_irqrestore(&power->spinlock, flags);
b8e36e13 AE	265	}
	266
	267	/* This function starts the modem netdev transmit queue, but only if the
	268	* STOPPED flag is set. That flag is cleared if it was set. If the queue
	269	* was restarted, the STARTED flag is set; this allows ipa_start_xmit()
	270	* to skip stopping the queue in the event of a race.
	271	*/
	272	void ipa_power_modem_queue_wake(struct ipa *ipa)
	273	{
7aa0e8b8	274	struct ipa_power *power = ipa->power;
b8e36e13 AE	275	unsigned long flags;
b8e36e13 AE	276
7aa0e8b8	277	spin_lock_irqsave(&power->spinlock, flags);
b8e36e13	278
7aa0e8b8 AE	279	if (__test_and_clear_bit(IPA_POWER_FLAG_STOPPED, power->flags)) {
7aa0e8b8 AE	280	__set_bit(IPA_POWER_FLAG_STARTED, power->flags);
b8e36e13 AE	281	netif_wake_queue(ipa->modem_netdev);
	282	}
	283
7aa0e8b8	284	spin_unlock_irqrestore(&power->spinlock, flags);
b8e36e13 AE	285	}
	286
	287	/* This function clears the STARTED flag once the TX queue is operating */
	288	void ipa_power_modem_queue_active(struct ipa *ipa)
	289	{
7aa0e8b8	290	clear_bit(IPA_POWER_FLAG_STARTED, ipa->power->flags);
b8e36e13 AE	291	}
b8e36e13 AE	292
34a08176 AE	293	static int ipa_power_retention_init(struct ipa_power *power)
	294	{
	295	struct qmp *qmp = qmp_get(power->dev);
	296
	297	if (IS_ERR(qmp)) {
	298	if (PTR_ERR(qmp) == -EPROBE_DEFER)
	299	return -EPROBE_DEFER;
	300
	301	/* We assume any other error means it's not defined/needed */
	302	qmp = NULL;
	303	}
	304	power->qmp = qmp;
	305
	306	return 0;
	307	}
	308
	309	static void ipa_power_retention_exit(struct ipa_power *power)
	310	{
	311	qmp_put(power->qmp);
	312	power->qmp = NULL;
	313	}
	314
	315	/* Control register retention on power collapse */
	316	void ipa_power_retention(struct ipa *ipa, bool enable)
	317	{
	318	static const char fmt[] = "{ class: bcm, res: ipa_pc, val: %c }";
	319	struct ipa_power *power = ipa->power;
	320	char buf[36]; /* Exactly enough for fmt[]; size a multiple of 4 */
	321	int ret;
	322
	323	if (!power->qmp)
	324	return; /* Not needed on this platform */
	325
	326	(void)snprintf(buf, sizeof(buf), fmt, enable ? '1' : '0');
	327
	328	ret = qmp_send(power->qmp, buf, sizeof(buf));
	329	if (ret)
	330	dev_err(power->dev, "error %d sending QMP %sable request\n",
	331	ret, enable ? "en" : "dis");
	332	}
	333
d430fe4b	334	int ipa_power_setup(struct ipa *ipa)
afe1baa8	335	{
d430fe4b AE	336	int ret;
d430fe4b AE	337
afe1baa8 AE	338	ipa_interrupt_add(ipa->interrupt, IPA_IRQ_TX_SUSPEND,
afe1baa8 AE	339	ipa_suspend_handler);
d430fe4b AE	340
	341	ret = device_init_wakeup(&ipa->pdev->dev, true);
	342	if (ret)
	343	ipa_interrupt_remove(ipa->interrupt, IPA_IRQ_TX_SUSPEND);
	344
	345	return ret;
afe1baa8 AE	346	}
	347
	348	void ipa_power_teardown(struct ipa *ipa)
	349	{
d430fe4b	350	(void)device_init_wakeup(&ipa->pdev->dev, false);
afe1baa8 AE	351	ipa_interrupt_remove(ipa->interrupt, IPA_IRQ_TX_SUSPEND);
	352	}
	353
7aa0e8b8 AE	354	/* Initialize IPA power management */
	355	struct ipa_power *
	356	ipa_power_init(struct device dev, const struct ipa_power_data data)
ba764c4d	357	{
7aa0e8b8	358	struct ipa_power *power;
ba764c4d	359	struct clk *clk;
8ee7ec48	360	size_t size;
ba764c4d AE	361	int ret;
	362
	363	clk = clk_get(dev, "core");
	364	if (IS_ERR(clk)) {
4c7ccfcd AE	365	dev_err_probe(dev, PTR_ERR(clk), "error getting core clock\n");
4c7ccfcd AE	366
ba764c4d AE	367	return ERR_CAST(clk);
	368	}
	369
91d02f95	370	ret = clk_set_rate(clk, data->core_clock_rate);
ba764c4d	371	if (ret) {
91d02f95 AE	372	dev_err(dev, "error %d setting core clock rate to %u\n",
91d02f95 AE	373	ret, data->core_clock_rate);
ba764c4d AE	374	goto err_clk_put;
	375	}
	376
cb631a63 AE	377	size = struct_size(power, interconnect, data->interconnect_count);
cb631a63 AE	378	power = kzalloc(size, GFP_KERNEL);
7aa0e8b8	379	if (!power) {
ba764c4d AE	380	ret = -ENOMEM;
	381	goto err_clk_put;
	382	}
7aa0e8b8 AE	383	power->dev = dev;
	384	power->core = clk;
	385	spin_lock_init(&power->spinlock);
	386	power->interconnect_count = data->interconnect_count;
ba764c4d	387
37e0cf33	388	ret = ipa_interconnect_init(power, data->interconnect_data);
ba764c4d AE	389	if (ret)
	390	goto err_kfree;
	391
34a08176 AE	392	ret = ipa_power_retention_init(power);
	393	if (ret)
	394	goto err_interconnect_exit;
	395
1aac309d AE	396	pm_runtime_set_autosuspend_delay(dev, IPA_AUTOSUSPEND_DELAY);
1aac309d AE	397	pm_runtime_use_autosuspend(dev);
63de79f0 AE	398	pm_runtime_enable(dev);
63de79f0 AE	399
7aa0e8b8	400	return power;
ba764c4d	401
34a08176 AE	402	err_interconnect_exit:
34a08176 AE	403	ipa_interconnect_exit(power);
ba764c4d	404	err_kfree:
7aa0e8b8	405	kfree(power);
ba764c4d AE	406	err_clk_put:
	407	clk_put(clk);
	408
	409	return ERR_PTR(ret);
	410	}
	411
7aa0e8b8 AE	412	/* Inverse of ipa_power_init() */
7aa0e8b8 AE	413	void ipa_power_exit(struct ipa_power *power)
ba764c4d	414	{
7aa0e8b8 AE	415	struct device *dev = power->dev;
7aa0e8b8 AE	416	struct clk *clk = power->core;
ba764c4d	417
1aac309d AE	418	pm_runtime_disable(dev);
1aac309d AE	419	pm_runtime_dont_use_autosuspend(dev);
34a08176	420	ipa_power_retention_exit(power);
7aa0e8b8 AE	421	ipa_interconnect_exit(power);
7aa0e8b8 AE	422	kfree(power);
ba764c4d AE	423	clk_put(clk);
ba764c4d AE	424	}
73ff316d	425
73ff316d	426	const struct dev_pm_ops ipa_pm_ops = {
b9c532c1 AE	427	.suspend = ipa_suspend,
b9c532c1 AE	428	.resume = ipa_resume,
63de79f0 AE	429	.runtime_suspend = ipa_runtime_suspend,
63de79f0 AE	430	.runtime_resume = ipa_runtime_resume,
73ff316d	431	};