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