1// SPDX-License-Identifier: GPL-2.0
  2
  3/* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
  4 * Copyright (C) 2018-2024 Linaro Ltd.
  5 */
  6
  7#include <linux/clk.h>
  8#include <linux/device.h>
  9#include <linux/interconnect.h>
 10#include <linux/pm.h>
 11#include <linux/pm_runtime.h>
 12
 13#include "linux/soc/qcom/qcom_aoss.h"
 14
 15#include "ipa.h"
 16#include "ipa_data.h"
 17#include "ipa_endpoint.h"
 18#include "ipa_interrupt.h"
 19#include "ipa_modem.h"
 20#include "ipa_power.h"
 21
 22/**
 23 * DOC: IPA Power Management
 24 *
 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.
 30 *
 31 * The core clock currently runs at a fixed clock rate when enabled,
 32 * an all interconnects use a fixed average and peak bandwidth.
 33 */
 34
 35#define IPA_AUTOSUSPEND_DELAY	500	/* milliseconds */
 36
 37/**
 38 * struct ipa_power - IPA power management information
 39 * @dev:		IPA device pointer
 40 * @core:		IPA core clock
 41 * @qmp:		QMP handle for AOSS communication
 42 * @interconnect_count:	Number of elements in interconnect[]
 43 * @interconnect:	Interconnect array
 44 */
 45struct ipa_power {
 46	struct device *dev;
 47	struct clk *core;
 48	struct qmp *qmp;
 49	u32 interconnect_count;
 50	struct icc_bulk_data interconnect[] __counted_by(interconnect_count);
 51};
 52
 53/* Initialize interconnects required for IPA operation */
 54static int ipa_interconnect_init(struct ipa_power *power,
 55				 const struct ipa_interconnect_data *data)
 56{
 57	struct icc_bulk_data *interconnect;
 58	int ret;
 59	u32 i;
 60
 61	/* Initialize our interconnect data array for bulk operations */
 62	interconnect = &power->interconnect[0];
 63	for (i = 0; i < power->interconnect_count; i++) {
 64		/* interconnect->path is filled in by of_icc_bulk_get() */
 65		interconnect->name = data->name;
 66		interconnect->avg_bw = data->average_bandwidth;
 67		interconnect->peak_bw = data->peak_bandwidth;
 68		data++;
 69		interconnect++;
 70	}
 71
 72	ret = of_icc_bulk_get(power->dev, power->interconnect_count,
 73			      power->interconnect);
 74	if (ret)
 75		return ret;
 76
 77	/* All interconnects are initially disabled */
 78	icc_bulk_disable(power->interconnect_count, power->interconnect);
 79
 80	/* Set the bandwidth values to be used when enabled */
 81	ret = icc_bulk_set_bw(power->interconnect_count, power->interconnect);
 82	if (ret)
 83		icc_bulk_put(power->interconnect_count, power->interconnect);
 84
 85	return ret;
 86}
 87
 88/* Inverse of ipa_interconnect_init() */
 89static void ipa_interconnect_exit(struct ipa_power *power)
 90{
 91	icc_bulk_put(power->interconnect_count, power->interconnect);
 92}
 93
 94/* Enable IPA power, enabling interconnects and the core clock */
 95static int ipa_power_enable(struct ipa *ipa)
 96{
 97	struct ipa_power *power = ipa->power;
 98	int ret;
 99
100	ret = icc_bulk_enable(power->interconnect_count, power->interconnect);
101	if (ret)
102		return ret;
103
104	ret = clk_prepare_enable(power->core);
105	if (ret) {
106		dev_err(power->dev, "error %d enabling core clock\n", ret);
107		icc_bulk_disable(power->interconnect_count,
108				 power->interconnect);
109	}
110
111	return ret;
112}
113
114/* Inverse of ipa_power_enable() */
115static void ipa_power_disable(struct ipa *ipa)
116{
117	struct ipa_power *power = ipa->power;
118
119	clk_disable_unprepare(power->core);
120
121	icc_bulk_disable(power->interconnect_count, power->interconnect);
122}
123
124static int ipa_runtime_suspend(struct device *dev)
125{
126	struct ipa *ipa = dev_get_drvdata(dev);
127
128	/* Endpoints aren't usable until setup is complete */
129	if (ipa->setup_complete) {
130		ipa_endpoint_suspend(ipa);
131		gsi_suspend(&ipa->gsi);
132	}
133
134	ipa_power_disable(ipa);
135
136	return 0;
137}
138
139static int ipa_runtime_resume(struct device *dev)
140{
141	struct ipa *ipa = dev_get_drvdata(dev);
142	int ret;
143
144	ret = ipa_power_enable(ipa);
145	if (WARN_ON(ret < 0))
146		return ret;
147
148	/* Endpoints aren't usable until setup is complete */
149	if (ipa->setup_complete) {
150		gsi_resume(&ipa->gsi);
151		ipa_endpoint_resume(ipa);
152	}
153
154	return 0;
155}
156
157static int ipa_suspend(struct device *dev)
158{
159	struct ipa *ipa = dev_get_drvdata(dev);
160
161	/* Increment the disable depth to ensure that the IRQ won't
162	 * be re-enabled until the matching _enable call in
163	 * ipa_resume(). We do this to ensure that the interrupt
164	 * handler won't run whilst PM runtime is disabled.
165	 *
166	 * Note that disabling the IRQ is NOT the same as disabling
167	 * irq wake. If wakeup is enabled for the IPA then the IRQ
168	 * will still cause the system to wake up, see irq_set_irq_wake().
169	 */
170	ipa_interrupt_irq_disable(ipa);
171
172	return pm_runtime_force_suspend(dev);
173}
174
175static int ipa_resume(struct device *dev)
176{
177	struct ipa *ipa = dev_get_drvdata(dev);
178	int ret;
179
180	ret = pm_runtime_force_resume(dev);
181
182	/* Now that PM runtime is enabled again it's safe
183	 * to turn the IRQ back on and process any data
184	 * that was received during suspend.
185	 */
186	ipa_interrupt_irq_enable(ipa);
187
188	return ret;
189}
190
191/* Return the current IPA core clock rate */
192u32 ipa_core_clock_rate(struct ipa *ipa)
193{
194	return ipa->power ? (u32)clk_get_rate(ipa->power->core) : 0;
195}
196
197static int ipa_power_retention_init(struct ipa_power *power)
198{
199	struct qmp *qmp = qmp_get(power->dev);
200
201	if (IS_ERR(qmp)) {
202		if (PTR_ERR(qmp) == -EPROBE_DEFER)
203			return -EPROBE_DEFER;
204
205		/* We assume any other error means it's not defined/needed */
206		qmp = NULL;
207	}
208	power->qmp = qmp;
209
210	return 0;
211}
212
213static void ipa_power_retention_exit(struct ipa_power *power)
214{
215	qmp_put(power->qmp);
216	power->qmp = NULL;
217}
218
219/* Control register retention on power collapse */
220void ipa_power_retention(struct ipa *ipa, bool enable)
221{
222	static const char fmt[] = "{ class: bcm, res: ipa_pc, val: %c }";
223	struct ipa_power *power = ipa->power;
224	int ret;
225
226	if (!power->qmp)
227		return;		/* Not needed on this platform */
228
229	ret = qmp_send(power->qmp, fmt, enable ? '1' : '0');
230	if (ret)
231		dev_err(power->dev, "error %d sending QMP %sable request\n",
232			ret, enable ? "en" : "dis");
233}
234
235/* Initialize IPA power management */
236struct ipa_power *
237ipa_power_init(struct device *dev, const struct ipa_power_data *data)
238{
239	struct ipa_power *power;
240	struct clk *clk;
241	size_t size;
242	int ret;
243
244	clk = clk_get(dev, "core");
245	if (IS_ERR(clk))
246		return dev_err_cast_probe(dev, clk, "error getting core clock\n");
247
248	ret = clk_set_rate(clk, data->core_clock_rate);
249	if (ret) {
250		dev_err(dev, "error %d setting core clock rate to %u\n",
251			ret, data->core_clock_rate);
252		goto err_clk_put;
253	}
254
255	size = struct_size(power, interconnect, data->interconnect_count);
256	power = kzalloc(size, GFP_KERNEL);
257	if (!power) {
258		ret = -ENOMEM;
259		goto err_clk_put;
260	}
261	power->dev = dev;
262	power->core = clk;
263	power->interconnect_count = data->interconnect_count;
264
265	ret = ipa_interconnect_init(power, data->interconnect_data);
266	if (ret)
267		goto err_kfree;
268
269	ret = ipa_power_retention_init(power);
270	if (ret)
271		goto err_interconnect_exit;
272
273	pm_runtime_set_autosuspend_delay(dev, IPA_AUTOSUSPEND_DELAY);
274	pm_runtime_use_autosuspend(dev);
275	pm_runtime_enable(dev);
276
277	return power;
278
279err_interconnect_exit:
280	ipa_interconnect_exit(power);
281err_kfree:
282	kfree(power);
283err_clk_put:
284	clk_put(clk);
285
286	return ERR_PTR(ret);
287}
288
289/* Inverse of ipa_power_init() */
290void ipa_power_exit(struct ipa_power *power)
291{
292	struct device *dev = power->dev;
293	struct clk *clk = power->core;
294
295	pm_runtime_disable(dev);
296	pm_runtime_dont_use_autosuspend(dev);
297	ipa_power_retention_exit(power);
298	ipa_interconnect_exit(power);
299	kfree(power);
300	clk_put(clk);
301}
302
303const struct dev_pm_ops ipa_pm_ops = {
304	.suspend		= ipa_suspend,
305	.resume			= ipa_resume,
306	.runtime_suspend	= ipa_runtime_suspend,
307	.runtime_resume		= ipa_runtime_resume,
308};