drivers/net/ipa/ipa_power.c

   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  */
  45 struct 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 */
  54 static 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() */
  89 static 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 */
  95 static 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() */
 115 static 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
 124 static 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
 139 static 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
 157 static 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
 175 static 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 */
 192 u32 ipa_core_clock_rate(struct ipa *ipa)
 193 {
 194         return ipa->power ? (u32)clk_get_rate(ipa->power->core) : 0;
 195 }
 196
 197 static 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
 213 static 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 */
 220 void 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 */
 236 struct ipa_power *
 237 ipa_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
 279 err_interconnect_exit:
 280         ipa_interconnect_exit(power);
 281 err_kfree:
 282         kfree(power);
 283 err_clk_put:
 284         clk_put(clk);
 285
 286         return ERR_PTR(ret);
 287 }
 288
 289 /* Inverse of ipa_power_init() */
 290 void 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
 303 const 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 };