1 files changed, 303 insertions, 0 deletions
diff --git a/drivers/soc/xilinx/zynqmp_power.c b/drivers/soc/xilinx/zynqmp_power.c
new file mode 100644
index 000000000..78a8a7545
--- /dev/null
+++ b/drivers/soc/xilinx/zynqmp_power.c
@@ -0,0 +1,303 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Xilinx Zynq MPSoC Power Management
+ *
+ *  Copyright (C) 2014-2019 Xilinx, Inc.
+ *
+ *  Davorin Mista <davorin.mista@aggios.com>
+ *  Jolly Shah <jollys@xilinx.com>
+ *  Rajan Vaja <rajan.vaja@xilinx.com>
+ */
+
+#include <linux/mailbox_client.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/reboot.h>
+#include <linux/suspend.h>
+
+#include <linux/firmware/xlnx-zynqmp.h>
+#include <linux/firmware/xlnx-event-manager.h>
+#include <linux/mailbox/zynqmp-ipi-message.h>
+
+/**
+ * struct zynqmp_pm_work_struct - Wrapper for struct work_struct
+ * @callback_work:	Work structure
+ * @args:		Callback arguments
+ */
+struct zynqmp_pm_work_struct {
+	struct work_struct callback_work;
+	u32 args[CB_ARG_CNT];
+};
+
+static struct zynqmp_pm_work_struct *zynqmp_pm_init_suspend_work;
+static struct mbox_chan *rx_chan;
+static bool event_registered;
+
+enum pm_suspend_mode {
+	PM_SUSPEND_MODE_FIRST = 0,
+	PM_SUSPEND_MODE_STD = PM_SUSPEND_MODE_FIRST,
+	PM_SUSPEND_MODE_POWER_OFF,
+};
+
+#define PM_SUSPEND_MODE_FIRST	PM_SUSPEND_MODE_STD
+
+static const char *const suspend_modes[] = {
+	[PM_SUSPEND_MODE_STD] = "standard",
+	[PM_SUSPEND_MODE_POWER_OFF] = "power-off",
+};
+
+static enum pm_suspend_mode suspend_mode = PM_SUSPEND_MODE_STD;
+
+static void zynqmp_pm_get_callback_data(u32 *buf)
+{
+	zynqmp_pm_invoke_fn(GET_CALLBACK_DATA, 0, 0, 0, 0, buf);
+}
+
+static void suspend_event_callback(const u32 *payload, void *data)
+{
+	/* First element is callback API ID, others are callback arguments */
+	if (work_pending(&zynqmp_pm_init_suspend_work->callback_work))
+		return;
+
+	/* Copy callback arguments into work's structure */
+	memcpy(zynqmp_pm_init_suspend_work->args, &payload[1],
+	       sizeof(zynqmp_pm_init_suspend_work->args));
+
+	queue_work(system_unbound_wq, &zynqmp_pm_init_suspend_work->callback_work);
+}
+
+static irqreturn_t zynqmp_pm_isr(int irq, void *data)
+{
+	u32 payload[CB_PAYLOAD_SIZE];
+
+	zynqmp_pm_get_callback_data(payload);
+
+	/* First element is callback API ID, others are callback arguments */
+	if (payload[0] == PM_INIT_SUSPEND_CB) {
+		switch (payload[1]) {
+		case SUSPEND_SYSTEM_SHUTDOWN:
+			orderly_poweroff(true);
+			break;
+		case SUSPEND_POWER_REQUEST:
+			pm_suspend(PM_SUSPEND_MEM);
+			break;
+		default:
+			pr_err("%s Unsupported InitSuspendCb reason "
+				"code %d\n", __func__, payload[1]);
+		}
+	}
+
+	return IRQ_HANDLED;
+}
+
+static void ipi_receive_callback(struct mbox_client *cl, void *data)
+{
+	struct zynqmp_ipi_message *msg = (struct zynqmp_ipi_message *)data;
+	u32 payload[CB_PAYLOAD_SIZE];
+	int ret;
+
+	memcpy(payload, msg->data, sizeof(msg->len));
+	/* First element is callback API ID, others are callback arguments */
+	if (payload[0] == PM_INIT_SUSPEND_CB) {
+		if (work_pending(&zynqmp_pm_init_suspend_work->callback_work))
+			return;
+
+		/* Copy callback arguments into work's structure */
+		memcpy(zynqmp_pm_init_suspend_work->args, &payload[1],
+		       sizeof(zynqmp_pm_init_suspend_work->args));
+
+		queue_work(system_unbound_wq,
+			   &zynqmp_pm_init_suspend_work->callback_work);
+
+		/* Send NULL message to mbox controller to ack the message */
+		ret = mbox_send_message(rx_chan, NULL);
+		if (ret)
+			pr_err("IPI ack failed. Error %d\n", ret);
+	}
+}
+
+/**
+ * zynqmp_pm_init_suspend_work_fn - Initialize suspend
+ * @work:	Pointer to work_struct
+ *
+ * Bottom-half of PM callback IRQ handler.
+ */
+static void zynqmp_pm_init_suspend_work_fn(struct work_struct *work)
+{
+	struct zynqmp_pm_work_struct *pm_work =
+		container_of(work, struct zynqmp_pm_work_struct, callback_work);
+
+	if (pm_work->args[0] == SUSPEND_SYSTEM_SHUTDOWN) {
+		orderly_poweroff(true);
+	} else if (pm_work->args[0] == SUSPEND_POWER_REQUEST) {
+		pm_suspend(PM_SUSPEND_MEM);
+	} else {
+		pr_err("%s Unsupported InitSuspendCb reason code %d.\n",
+		       __func__, pm_work->args[0]);
+	}
+}
+
+static ssize_t suspend_mode_show(struct device *dev,
+				 struct device_attribute *attr, char *buf)
+{
+	char *s = buf;
+	int md;
+
+	for (md = PM_SUSPEND_MODE_FIRST; md < ARRAY_SIZE(suspend_modes); md++)
+		if (suspend_modes[md]) {
+			if (md == suspend_mode)
+				s += sprintf(s, "[%s] ", suspend_modes[md]);
+			else
+				s += sprintf(s, "%s ", suspend_modes[md]);
+		}
+
+	/* Convert last space to newline */
+	if (s != buf)
+		*(s - 1) = '\n';
+	return (s - buf);
+}
+
+static ssize_t suspend_mode_store(struct device *dev,
+				  struct device_attribute *attr,
+				  const char *buf, size_t count)
+{
+	int md, ret = -EINVAL;
+
+	for (md = PM_SUSPEND_MODE_FIRST; md < ARRAY_SIZE(suspend_modes); md++)
+		if (suspend_modes[md] &&
+		    sysfs_streq(suspend_modes[md], buf)) {
+			ret = 0;
+			break;
+		}
+
+	if (!ret && md != suspend_mode) {
+		ret = zynqmp_pm_set_suspend_mode(md);
+		if (likely(!ret))
+			suspend_mode = md;
+	}
+
+	return ret ? ret : count;
+}
+
+static DEVICE_ATTR_RW(suspend_mode);
+
+static int zynqmp_pm_probe(struct platform_device *pdev)
+{
+	int ret, irq;
+	u32 pm_api_version;
+	struct mbox_client *client;
+
+	zynqmp_pm_get_api_version(&pm_api_version);
+
+	/* Check PM API version number */
+	if (pm_api_version < ZYNQMP_PM_VERSION)
+		return -ENODEV;
+
+	/*
+	 * First try to use Xilinx Event Manager by registering suspend_event_callback
+	 * for suspend/shutdown event.
+	 * If xlnx_register_event() returns -EACCES (Xilinx Event Manager
+	 * is not available to use) or -ENODEV(Xilinx Event Manager not compiled),
+	 * then use ipi-mailbox or interrupt method.
+	 */
+	ret = xlnx_register_event(PM_INIT_SUSPEND_CB, 0, 0, false,
+				  suspend_event_callback, NULL);
+	if (!ret) {
+		zynqmp_pm_init_suspend_work = devm_kzalloc(&pdev->dev,
+							   sizeof(struct zynqmp_pm_work_struct),
+							   GFP_KERNEL);
+		if (!zynqmp_pm_init_suspend_work) {
+			xlnx_unregister_event(PM_INIT_SUSPEND_CB, 0, 0,
+					      suspend_event_callback, NULL);
+			return -ENOMEM;
+		}
+		event_registered = true;
+
+		INIT_WORK(&zynqmp_pm_init_suspend_work->callback_work,
+			  zynqmp_pm_init_suspend_work_fn);
+	} else if (ret != -EACCES && ret != -ENODEV) {
+		dev_err(&pdev->dev, "Failed to Register with Xilinx Event manager %d\n", ret);
+		return ret;
+	} else if (of_find_property(pdev->dev.of_node, "mboxes", NULL)) {
+		zynqmp_pm_init_suspend_work =
+			devm_kzalloc(&pdev->dev,
+				     sizeof(struct zynqmp_pm_work_struct),
+				     GFP_KERNEL);
+		if (!zynqmp_pm_init_suspend_work)
+			return -ENOMEM;
+
+		INIT_WORK(&zynqmp_pm_init_suspend_work->callback_work,
+			  zynqmp_pm_init_suspend_work_fn);
+		client = devm_kzalloc(&pdev->dev, sizeof(*client), GFP_KERNEL);
+		if (!client)
+			return -ENOMEM;
+
+		client->dev = &pdev->dev;
+		client->rx_callback = ipi_receive_callback;
+
+		rx_chan = mbox_request_channel_byname(client, "rx");
+		if (IS_ERR(rx_chan)) {
+			dev_err(&pdev->dev, "Failed to request rx channel\n");
+			return PTR_ERR(rx_chan);
+		}
+	} else if (of_find_property(pdev->dev.of_node, "interrupts", NULL)) {
+		irq = platform_get_irq(pdev, 0);
+		if (irq <= 0)
+			return -ENXIO;
+
+		ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
+						zynqmp_pm_isr,
+						IRQF_NO_SUSPEND | IRQF_ONESHOT,
+						dev_name(&pdev->dev),
+						&pdev->dev);
+		if (ret) {
+			dev_err(&pdev->dev, "devm_request_threaded_irq '%d' "
+					    "failed with %d\n", irq, ret);
+			return ret;
+		}
+	} else {
+		dev_err(&pdev->dev, "Required property not found in DT node\n");
+		return -ENOENT;
+	}
+
+	ret = sysfs_create_file(&pdev->dev.kobj, &dev_attr_suspend_mode.attr);
+	if (ret) {
+		if (event_registered) {
+			xlnx_unregister_event(PM_INIT_SUSPEND_CB, 0, 0, suspend_event_callback,
+					      NULL);
+			event_registered = false;
+		}
+		dev_err(&pdev->dev, "unable to create sysfs interface\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int zynqmp_pm_remove(struct platform_device *pdev)
+{
+	sysfs_remove_file(&pdev->dev.kobj, &dev_attr_suspend_mode.attr);
+	if (event_registered)
+		xlnx_unregister_event(PM_INIT_SUSPEND_CB, 0, 0, suspend_event_callback, NULL);
+
+	if (!rx_chan)
+		mbox_free_channel(rx_chan);
+
+	return 0;
+}
+
+static const struct of_device_id pm_of_match[] = {
+	{ .compatible = "xlnx,zynqmp-power", },
+	{ /* end of table */ },
+};
+MODULE_DEVICE_TABLE(of, pm_of_match);
+
+static struct platform_driver zynqmp_pm_platform_driver = {
+	.probe = zynqmp_pm_probe,
+	.remove = zynqmp_pm_remove,
+	.driver = {
+		.name = "zynqmp_power",
+		.of_match_table = pm_of_match,
+	},
+};
+module_platform_driver(zynqmp_pm_platform_driver);