1// SPDX-License-Identifier: GPL-2.0
2
3/* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved.
4 * Copyright (C) 2018-2022 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#include <linux/bitops.h>
13
14#include "linux/soc/qcom/qcom_aoss.h"
15
16#include "ipa.h"
17#include "ipa_power.h"
18#include "ipa_endpoint.h"
19#include "ipa_modem.h"
20#include "ipa_data.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(dev: power->dev, num_paths: power->interconnect_count,
73 paths: power->interconnect);
74 if (ret)
75 return ret;
76
77 /* All interconnects are initially disabled */
78 icc_bulk_disable(num_paths: power->interconnect_count, paths: power->interconnect);
79
80 /* Set the bandwidth values to be used when enabled */
81 ret = icc_bulk_set_bw(num_paths: power->interconnect_count, paths: power->interconnect);
82 if (ret)
83 icc_bulk_put(num_paths: power->interconnect_count, paths: 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(num_paths: power->interconnect_count, paths: 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(num_paths: power->interconnect_count, paths: power->interconnect);
101 if (ret)
102 return ret;
103
104 ret = clk_prepare_enable(clk: power->core);
105 if (ret) {
106 dev_err(power->dev, "error %d enabling core clock\n", ret);
107 icc_bulk_disable(num_paths: power->interconnect_count,
108 paths: 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(clk: power->core);
120
121 icc_bulk_disable(num_paths: power->interconnect_count, paths: 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(gsi: &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(gsi: &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(clk: ipa->power->core) : 0;
195}
196
197static int ipa_power_retention_init(struct ipa_power *power)
198{
199 struct qmp *qmp = qmp_get(dev: power->dev);
200
201 if (IS_ERR(ptr: qmp)) {
202 if (PTR_ERR(ptr: 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(qmp: 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(qmp: 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
235int ipa_power_setup(struct ipa *ipa)
236{
237 int ret;
238
239 ipa_interrupt_enable(ipa, ipa_irq: IPA_IRQ_TX_SUSPEND);
240
241 ret = device_init_wakeup(dev: ipa->dev, enable: true);
242 if (ret)
243 ipa_interrupt_disable(ipa, ipa_irq: IPA_IRQ_TX_SUSPEND);
244
245 return ret;
246}
247
248void ipa_power_teardown(struct ipa *ipa)
249{
250 (void)device_init_wakeup(dev: ipa->dev, enable: false);
251 ipa_interrupt_disable(ipa, ipa_irq: IPA_IRQ_TX_SUSPEND);
252}
253
254/* Initialize IPA power management */
255struct ipa_power *
256ipa_power_init(struct device *dev, const struct ipa_power_data *data)
257{
258 struct ipa_power *power;
259 struct clk *clk;
260 size_t size;
261 int ret;
262
263 clk = clk_get(dev, id: "core");
264 if (IS_ERR(ptr: clk)) {
265 dev_err_probe(dev, err: PTR_ERR(ptr: clk), fmt: "error getting core clock\n");
266
267 return ERR_CAST(ptr: clk);
268 }
269
270 ret = clk_set_rate(clk, rate: data->core_clock_rate);
271 if (ret) {
272 dev_err(dev, "error %d setting core clock rate to %u\n",
273 ret, data->core_clock_rate);
274 goto err_clk_put;
275 }
276
277 size = struct_size(power, interconnect, data->interconnect_count);
278 power = kzalloc(size, GFP_KERNEL);
279 if (!power) {
280 ret = -ENOMEM;
281 goto err_clk_put;
282 }
283 power->dev = dev;
284 power->core = clk;
285 power->interconnect_count = data->interconnect_count;
286
287 ret = ipa_interconnect_init(power, data: data->interconnect_data);
288 if (ret)
289 goto err_kfree;
290
291 ret = ipa_power_retention_init(power);
292 if (ret)
293 goto err_interconnect_exit;
294
295 pm_runtime_set_autosuspend_delay(dev, IPA_AUTOSUSPEND_DELAY);
296 pm_runtime_use_autosuspend(dev);
297 pm_runtime_enable(dev);
298
299 return power;
300
301err_interconnect_exit:
302 ipa_interconnect_exit(power);
303err_kfree:
304 kfree(objp: power);
305err_clk_put:
306 clk_put(clk);
307
308 return ERR_PTR(error: ret);
309}
310
311/* Inverse of ipa_power_init() */
312void ipa_power_exit(struct ipa_power *power)
313{
314 struct device *dev = power->dev;
315 struct clk *clk = power->core;
316
317 pm_runtime_disable(dev);
318 pm_runtime_dont_use_autosuspend(dev);
319 ipa_power_retention_exit(power);
320 ipa_interconnect_exit(power);
321 kfree(objp: power);
322 clk_put(clk);
323}
324
325const struct dev_pm_ops ipa_pm_ops = {
326 .suspend = ipa_suspend,
327 .resume = ipa_resume,
328 .runtime_suspend = ipa_runtime_suspend,
329 .runtime_resume = ipa_runtime_resume,
330};
331

source code of linux/drivers/net/ipa/ipa_power.c