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/of.h> 15 #include <linux/platform_device.h> 16 #include <linux/reboot.h> 17 #include <linux/suspend.h> 18 19 #include <linux/firmware/xlnx-zynqmp.h> 20 #include <linux/firmware/xlnx-event-manager.h> 21 #include <linux/mailbox/zynqmp-ipi-message.h> 22 23 /** 24 * struct zynqmp_pm_work_struct - Wrapper for struct work_struct 25 * @callback_work: Work structure 26 * @args: Callback arguments 27 */ 28 struct zynqmp_pm_work_struct { 29 struct work_struct callback_work; 30 u32 args[CB_ARG_CNT]; 31 }; 32 33 static struct zynqmp_pm_work_struct *zynqmp_pm_init_suspend_work; 34 static struct mbox_chan *rx_chan; 35 static bool event_registered; 36 37 enum pm_suspend_mode { 38 PM_SUSPEND_MODE_FIRST = 0, 39 PM_SUSPEND_MODE_STD = PM_SUSPEND_MODE_FIRST, 40 PM_SUSPEND_MODE_POWER_OFF, 41 }; 42 43 #define PM_SUSPEND_MODE_FIRST PM_SUSPEND_MODE_STD 44 45 static const char *const suspend_modes[] = { 46 [PM_SUSPEND_MODE_STD] = "standard", 47 [PM_SUSPEND_MODE_POWER_OFF] = "power-off", 48 }; 49 50 static enum pm_suspend_mode suspend_mode = PM_SUSPEND_MODE_STD; 51 52 static void zynqmp_pm_get_callback_data(u32 *buf) 53 { 54 zynqmp_pm_invoke_fn(GET_CALLBACK_DATA, 0, 0, 0, 0, buf); 55 } 56 57 static void suspend_event_callback(const u32 *payload, void *data) 58 { 59 /* First element is callback API ID, others are callback arguments */ 60 if (work_pending(&zynqmp_pm_init_suspend_work->callback_work)) 61 return; 62 63 /* Copy callback arguments into work's structure */ 64 memcpy(zynqmp_pm_init_suspend_work->args, &payload[1], 65 sizeof(zynqmp_pm_init_suspend_work->args)); 66 67 queue_work(system_unbound_wq, &zynqmp_pm_init_suspend_work->callback_work); 68 } 69 70 static irqreturn_t zynqmp_pm_isr(int irq, void *data) 71 { 72 u32 payload[CB_PAYLOAD_SIZE]; 73 74 zynqmp_pm_get_callback_data(payload); 75 76 /* First element is callback API ID, others are callback arguments */ 77 if (payload[0] == PM_INIT_SUSPEND_CB) { 78 switch (payload[1]) { 79 case SUSPEND_SYSTEM_SHUTDOWN: 80 orderly_poweroff(true); 81 break; 82 case SUSPEND_POWER_REQUEST: 83 pm_suspend(PM_SUSPEND_MEM); 84 break; 85 default: 86 pr_err("%s Unsupported InitSuspendCb reason " 87 "code %d\n", __func__, payload[1]); 88 } 89 } 90 91 return IRQ_HANDLED; 92 } 93 94 static void ipi_receive_callback(struct mbox_client *cl, void *data) 95 { 96 struct zynqmp_ipi_message *msg = (struct zynqmp_ipi_message *)data; 97 u32 payload[CB_PAYLOAD_SIZE]; 98 int ret; 99 100 memcpy(payload, msg->data, sizeof(msg->len)); 101 /* First element is callback API ID, others are callback arguments */ 102 if (payload[0] == PM_INIT_SUSPEND_CB) { 103 if (work_pending(&zynqmp_pm_init_suspend_work->callback_work)) 104 return; 105 106 /* Copy callback arguments into work's structure */ 107 memcpy(zynqmp_pm_init_suspend_work->args, &payload[1], 108 sizeof(zynqmp_pm_init_suspend_work->args)); 109 110 queue_work(system_unbound_wq, 111 &zynqmp_pm_init_suspend_work->callback_work); 112 113 /* Send NULL message to mbox controller to ack the message */ 114 ret = mbox_send_message(rx_chan, NULL); 115 if (ret) 116 pr_err("IPI ack failed. Error %d\n", ret); 117 } 118 } 119 120 /** 121 * zynqmp_pm_init_suspend_work_fn - Initialize suspend 122 * @work: Pointer to work_struct 123 * 124 * Bottom-half of PM callback IRQ handler. 125 */ 126 static void zynqmp_pm_init_suspend_work_fn(struct work_struct *work) 127 { 128 struct zynqmp_pm_work_struct *pm_work = 129 container_of(work, struct zynqmp_pm_work_struct, callback_work); 130 131 if (pm_work->args[0] == SUSPEND_SYSTEM_SHUTDOWN) { 132 orderly_poweroff(true); 133 } else if (pm_work->args[0] == SUSPEND_POWER_REQUEST) { 134 pm_suspend(PM_SUSPEND_MEM); 135 } else { 136 pr_err("%s Unsupported InitSuspendCb reason code %d.\n", 137 __func__, pm_work->args[0]); 138 } 139 } 140 141 static ssize_t suspend_mode_show(struct device *dev, 142 struct device_attribute *attr, char *buf) 143 { 144 char *s = buf; 145 int md; 146 147 for (md = PM_SUSPEND_MODE_FIRST; md < ARRAY_SIZE(suspend_modes); md++) 148 if (suspend_modes[md]) { 149 if (md == suspend_mode) 150 s += sprintf(s, "[%s] ", suspend_modes[md]); 151 else 152 s += sprintf(s, "%s ", suspend_modes[md]); 153 } 154 155 /* Convert last space to newline */ 156 if (s != buf) 157 *(s - 1) = '\n'; 158 return (s - buf); 159 } 160 161 static ssize_t suspend_mode_store(struct device *dev, 162 struct device_attribute *attr, 163 const char *buf, size_t count) 164 { 165 int md, ret = -EINVAL; 166 167 for (md = PM_SUSPEND_MODE_FIRST; md < ARRAY_SIZE(suspend_modes); md++) 168 if (suspend_modes[md] && 169 sysfs_streq(suspend_modes[md], buf)) { 170 ret = 0; 171 break; 172 } 173 174 if (!ret && md != suspend_mode) { 175 ret = zynqmp_pm_set_suspend_mode(md); 176 if (likely(!ret)) 177 suspend_mode = md; 178 } 179 180 return ret ? ret : count; 181 } 182 183 static DEVICE_ATTR_RW(suspend_mode); 184 185 static int zynqmp_pm_probe(struct platform_device *pdev) 186 { 187 int ret, irq; 188 u32 pm_api_version; 189 struct mbox_client *client; 190 191 zynqmp_pm_get_api_version(&pm_api_version); 192 193 /* Check PM API version number */ 194 if (pm_api_version < ZYNQMP_PM_VERSION) 195 return -ENODEV; 196 197 /* 198 * First try to use Xilinx Event Manager by registering suspend_event_callback 199 * for suspend/shutdown event. 200 * If xlnx_register_event() returns -EACCES (Xilinx Event Manager 201 * is not available to use) or -ENODEV(Xilinx Event Manager not compiled), 202 * then use ipi-mailbox or interrupt method. 203 */ 204 ret = xlnx_register_event(PM_INIT_SUSPEND_CB, 0, 0, false, 205 suspend_event_callback, NULL); 206 if (!ret) { 207 zynqmp_pm_init_suspend_work = devm_kzalloc(&pdev->dev, 208 sizeof(struct zynqmp_pm_work_struct), 209 GFP_KERNEL); 210 if (!zynqmp_pm_init_suspend_work) { 211 xlnx_unregister_event(PM_INIT_SUSPEND_CB, 0, 0, 212 suspend_event_callback, NULL); 213 return -ENOMEM; 214 } 215 event_registered = true; 216 217 INIT_WORK(&zynqmp_pm_init_suspend_work->callback_work, 218 zynqmp_pm_init_suspend_work_fn); 219 } else if (ret != -EACCES && ret != -ENODEV) { 220 dev_err(&pdev->dev, "Failed to Register with Xilinx Event manager %d\n", ret); 221 return ret; 222 } else if (of_property_present(pdev->dev.of_node, "mboxes")) { 223 zynqmp_pm_init_suspend_work = 224 devm_kzalloc(&pdev->dev, 225 sizeof(struct zynqmp_pm_work_struct), 226 GFP_KERNEL); 227 if (!zynqmp_pm_init_suspend_work) 228 return -ENOMEM; 229 230 INIT_WORK(&zynqmp_pm_init_suspend_work->callback_work, 231 zynqmp_pm_init_suspend_work_fn); 232 client = devm_kzalloc(&pdev->dev, sizeof(*client), GFP_KERNEL); 233 if (!client) 234 return -ENOMEM; 235 236 client->dev = &pdev->dev; 237 client->rx_callback = ipi_receive_callback; 238 239 rx_chan = mbox_request_channel_byname(client, "rx"); 240 if (IS_ERR(rx_chan)) { 241 dev_err(&pdev->dev, "Failed to request rx channel\n"); 242 return PTR_ERR(rx_chan); 243 } 244 } else if (of_property_present(pdev->dev.of_node, "interrupts")) { 245 irq = platform_get_irq(pdev, 0); 246 if (irq < 0) 247 return irq; 248 249 ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, 250 zynqmp_pm_isr, 251 IRQF_NO_SUSPEND | IRQF_ONESHOT, 252 dev_name(&pdev->dev), 253 &pdev->dev); 254 if (ret) { 255 dev_err(&pdev->dev, "devm_request_threaded_irq '%d' " 256 "failed with %d\n", irq, ret); 257 return ret; 258 } 259 } else { 260 dev_err(&pdev->dev, "Required property not found in DT node\n"); 261 return -ENOENT; 262 } 263 264 ret = sysfs_create_file(&pdev->dev.kobj, &dev_attr_suspend_mode.attr); 265 if (ret) { 266 if (event_registered) { 267 xlnx_unregister_event(PM_INIT_SUSPEND_CB, 0, 0, suspend_event_callback, 268 NULL); 269 event_registered = false; 270 } 271 dev_err(&pdev->dev, "unable to create sysfs interface\n"); 272 return ret; 273 } 274 275 return 0; 276 } 277 278 static int zynqmp_pm_remove(struct platform_device *pdev) 279 { 280 sysfs_remove_file(&pdev->dev.kobj, &dev_attr_suspend_mode.attr); 281 if (event_registered) 282 xlnx_unregister_event(PM_INIT_SUSPEND_CB, 0, 0, suspend_event_callback, NULL); 283 284 if (!rx_chan) 285 mbox_free_channel(rx_chan); 286 287 return 0; 288 } 289 290 static const struct of_device_id pm_of_match[] = { 291 { .compatible = "xlnx,zynqmp-power", }, 292 { /* end of table */ }, 293 }; 294 MODULE_DEVICE_TABLE(of, pm_of_match); 295 296 static struct platform_driver zynqmp_pm_platform_driver = { 297 .probe = zynqmp_pm_probe, 298 .remove = zynqmp_pm_remove, 299 .driver = { 300 .name = "zynqmp_power", 301 .of_match_table = pm_of_match, 302 }, 303 }; 304 module_platform_driver(zynqmp_pm_platform_driver); 305