drivers/soc/xilinx/zynqmp_power.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * Xilinx Zynq MPSoC Power Management
   4  *
   5  *  Copyright (C) 2014-2019 Xilinx, Inc.
   6  *
   7  *  Davorin Mista <davorin.mista@aggios.com>
   8  *  Jolly Shah <jollys@xilinx.com>
   9  *  Rajan Vaja <rajan.vaja@xilinx.com>
  10  */
  11
  12 #include <linux/mailbox_client.h>
  13 #include <linux/module.h>
  14 #include <linux/platform_device.h>
  15 #include <linux/reboot.h>
  16 #include <linux/suspend.h>
  17
  18 #include <linux/firmware/xlnx-zynqmp.h>
  19 #include <linux/mailbox/zynqmp-ipi-message.h>
  20
  21 /**
  22  * struct zynqmp_pm_work_struct - Wrapper for struct work_struct
  23  * @callback_work:      Work structure
  24  * @args:               Callback arguments
  25  */
  26 struct zynqmp_pm_work_struct {
  27         struct work_struct callback_work;
  28         u32 args[CB_ARG_CNT];
  29 };
  30
  31 static struct zynqmp_pm_work_struct *zynqmp_pm_init_suspend_work;
  32 static struct mbox_chan *rx_chan;
  33 static const struct zynqmp_eemi_ops *eemi_ops;
  34
  35 enum pm_suspend_mode {
  36         PM_SUSPEND_MODE_FIRST = 0,
  37         PM_SUSPEND_MODE_STD = PM_SUSPEND_MODE_FIRST,
  38         PM_SUSPEND_MODE_POWER_OFF,
  39 };
  40
  41 #define PM_SUSPEND_MODE_FIRST   PM_SUSPEND_MODE_STD
  42
  43 static const char *const suspend_modes[] = {
  44         [PM_SUSPEND_MODE_STD] = "standard",
  45         [PM_SUSPEND_MODE_POWER_OFF] = "power-off",
  46 };
  47
  48 static enum pm_suspend_mode suspend_mode = PM_SUSPEND_MODE_STD;
  49
  50 enum pm_api_cb_id {
  51         PM_INIT_SUSPEND_CB = 30,
  52         PM_ACKNOWLEDGE_CB,
  53         PM_NOTIFY_CB,
  54 };
  55
  56 static void zynqmp_pm_get_callback_data(u32 *buf)
  57 {
  58         zynqmp_pm_invoke_fn(GET_CALLBACK_DATA, 0, 0, 0, 0, buf);
  59 }
  60
  61 static irqreturn_t zynqmp_pm_isr(int irq, void *data)
  62 {
  63         u32 payload[CB_PAYLOAD_SIZE];
  64
  65         zynqmp_pm_get_callback_data(payload);
  66
  67         /* First element is callback API ID, others are callback arguments */
  68         if (payload[0] == PM_INIT_SUSPEND_CB) {
  69                 switch (payload[1]) {
  70                 case SUSPEND_SYSTEM_SHUTDOWN:
  71                         orderly_poweroff(true);
  72                         break;
  73                 case SUSPEND_POWER_REQUEST:
  74                         pm_suspend(PM_SUSPEND_MEM);
  75                         break;
  76                 default:
  77                         pr_err("%s Unsupported InitSuspendCb reason "
  78                                 "code %d\n", __func__, payload[1]);
  79                 }
  80         }
  81
  82         return IRQ_HANDLED;
  83 }
  84
  85 static void ipi_receive_callback(struct mbox_client *cl, void *data)
  86 {
  87         struct zynqmp_ipi_message *msg = (struct zynqmp_ipi_message *)data;
  88         u32 payload[CB_PAYLOAD_SIZE];
  89         int ret;
  90
  91         memcpy(payload, msg->data, sizeof(msg->len));
  92         /* First element is callback API ID, others are callback arguments */
  93         if (payload[0] == PM_INIT_SUSPEND_CB) {
  94                 if (work_pending(&zynqmp_pm_init_suspend_work->callback_work))
  95                         return;
  96
  97                 /* Copy callback arguments into work's structure */
  98                 memcpy(zynqmp_pm_init_suspend_work->args, &payload[1],
  99                        sizeof(zynqmp_pm_init_suspend_work->args));
 100
 101                 queue_work(system_unbound_wq,
 102                            &zynqmp_pm_init_suspend_work->callback_work);
 103
 104                 /* Send NULL message to mbox controller to ack the message */
 105                 ret = mbox_send_message(rx_chan, NULL);
 106                 if (ret)
 107                         pr_err("IPI ack failed. Error %d\n", ret);
 108         }
 109 }
 110
 111 /**
 112  * zynqmp_pm_init_suspend_work_fn - Initialize suspend
 113  * @work:       Pointer to work_struct
 114  *
 115  * Bottom-half of PM callback IRQ handler.
 116  */
 117 static void zynqmp_pm_init_suspend_work_fn(struct work_struct *work)
 118 {
 119         struct zynqmp_pm_work_struct *pm_work =
 120                 container_of(work, struct zynqmp_pm_work_struct, callback_work);
 121
 122         if (pm_work->args[0] == SUSPEND_SYSTEM_SHUTDOWN) {
 123                 orderly_poweroff(true);
 124         } else if (pm_work->args[0] == SUSPEND_POWER_REQUEST) {
 125                 pm_suspend(PM_SUSPEND_MEM);
 126         } else {
 127                 pr_err("%s Unsupported InitSuspendCb reason code %d.\n",
 128                        __func__, pm_work->args[0]);
 129         }
 130 }
 131
 132 static ssize_t suspend_mode_show(struct device *dev,
 133                                  struct device_attribute *attr, char *buf)
 134 {
 135         char *s = buf;
 136         int md;
 137
 138         for (md = PM_SUSPEND_MODE_FIRST; md < ARRAY_SIZE(suspend_modes); md++)
 139                 if (suspend_modes[md]) {
 140                         if (md == suspend_mode)
 141                                 s += sprintf(s, "[%s] ", suspend_modes[md]);
 142                         else
 143                                 s += sprintf(s, "%s ", suspend_modes[md]);
 144                 }
 145
 146         /* Convert last space to newline */
 147         if (s != buf)
 148                 *(s - 1) = '\n';
 149         return (s - buf);
 150 }
 151
 152 static ssize_t suspend_mode_store(struct device *dev,
 153                                   struct device_attribute *attr,
 154                                   const char *buf, size_t count)
 155 {
 156         int md, ret = -EINVAL;
 157
 158         if (!eemi_ops->set_suspend_mode)
 159                 return ret;
 160
 161         for (md = PM_SUSPEND_MODE_FIRST; md < ARRAY_SIZE(suspend_modes); md++)
 162                 if (suspend_modes[md] &&
 163                     sysfs_streq(suspend_modes[md], buf)) {
 164                         ret = 0;
 165                         break;
 166                 }
 167
 168         if (!ret && md != suspend_mode) {
 169                 ret = eemi_ops->set_suspend_mode(md);
 170                 if (likely(!ret))
 171                         suspend_mode = md;
 172         }
 173
 174         return ret ? ret : count;
 175 }
 176
 177 static DEVICE_ATTR_RW(suspend_mode);
 178
 179 static int zynqmp_pm_probe(struct platform_device *pdev)
 180 {
 181         int ret, irq;
 182         u32 pm_api_version;
 183         struct mbox_client *client;
 184
 185         eemi_ops = zynqmp_pm_get_eemi_ops();
 186         if (IS_ERR(eemi_ops))
 187                 return PTR_ERR(eemi_ops);
 188
 189         if (!eemi_ops->get_api_version || !eemi_ops->init_finalize)
 190                 return -ENXIO;
 191
 192         eemi_ops->init_finalize();
 193         eemi_ops->get_api_version(&pm_api_version);
 194
 195         /* Check PM API version number */
 196         if (pm_api_version < ZYNQMP_PM_VERSION)
 197                 return -ENODEV;
 198
 199         if (of_find_property(pdev->dev.of_node, "mboxes", NULL)) {
 200                 zynqmp_pm_init_suspend_work =
 201                         devm_kzalloc(&pdev->dev,
 202                                      sizeof(struct zynqmp_pm_work_struct),
 203                                      GFP_KERNEL);
 204                 if (!zynqmp_pm_init_suspend_work)
 205                         return -ENOMEM;
 206
 207                 INIT_WORK(&zynqmp_pm_init_suspend_work->callback_work,
 208                           zynqmp_pm_init_suspend_work_fn);
 209                 client = devm_kzalloc(&pdev->dev, sizeof(*client), GFP_KERNEL);
 210                 if (!client)
 211                         return -ENOMEM;
 212
 213                 client->dev = &pdev->dev;
 214                 client->rx_callback = ipi_receive_callback;
 215
 216                 rx_chan = mbox_request_channel_byname(client, "rx");
 217                 if (IS_ERR(rx_chan)) {
 218                         dev_err(&pdev->dev, "Failed to request rx channel\n");
 219                         return IS_ERR(rx_chan);
 220                 }
 221         } else if (of_find_property(pdev->dev.of_node, "interrupts", NULL)) {
 222                 irq = platform_get_irq(pdev, 0);
 223                 if (irq <= 0)
 224                         return -ENXIO;
 225
 226                 ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
 227                                                 zynqmp_pm_isr,
 228                                                 IRQF_NO_SUSPEND | IRQF_ONESHOT,
 229                                                 dev_name(&pdev->dev),
 230                                                 &pdev->dev);
 231                 if (ret) {
 232                         dev_err(&pdev->dev, "devm_request_threaded_irq '%d' "
 233                                             "failed with %d\n", irq, ret);
 234                         return ret;
 235                 }
 236         } else {
 237                 dev_err(&pdev->dev, "Required property not found in DT node\n");
 238                 return -ENOENT;
 239         }
 240
 241         ret = sysfs_create_file(&pdev->dev.kobj, &dev_attr_suspend_mode.attr);
 242         if (ret) {
 243                 dev_err(&pdev->dev, "unable to create sysfs interface\n");
 244                 return ret;
 245         }
 246
 247         return 0;
 248 }
 249
 250 static int zynqmp_pm_remove(struct platform_device *pdev)
 251 {
 252         sysfs_remove_file(&pdev->dev.kobj, &dev_attr_suspend_mode.attr);
 253
 254         if (!rx_chan)
 255                 mbox_free_channel(rx_chan);
 256
 257         return 0;
 258 }
 259
 260 static const struct of_device_id pm_of_match[] = {
 261         { .compatible = "xlnx,zynqmp-power", },
 262         { /* end of table */ },
 263 };
 264 MODULE_DEVICE_TABLE(of, pm_of_match);
 265
 266 static struct platform_driver zynqmp_pm_platform_driver = {
 267         .probe = zynqmp_pm_probe,
 268         .remove = zynqmp_pm_remove,
 269         .driver = {
 270                 .name = "zynqmp_power",
 271                 .of_match_table = pm_of_match,
 272         },
 273 };
 274 module_platform_driver(zynqmp_pm_platform_driver);