1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Xilinx Zynq MPSoC Power Management
4  *
5  *  Copyright (C) 2014-2018 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 
20 enum pm_suspend_mode {
21 	PM_SUSPEND_MODE_FIRST = 0,
22 	PM_SUSPEND_MODE_STD = PM_SUSPEND_MODE_FIRST,
23 	PM_SUSPEND_MODE_POWER_OFF,
24 };
25 
26 #define PM_SUSPEND_MODE_FIRST	PM_SUSPEND_MODE_STD
27 
28 static const char *const suspend_modes[] = {
29 	[PM_SUSPEND_MODE_STD] = "standard",
30 	[PM_SUSPEND_MODE_POWER_OFF] = "power-off",
31 };
32 
33 static enum pm_suspend_mode suspend_mode = PM_SUSPEND_MODE_STD;
34 static const struct zynqmp_eemi_ops *eemi_ops;
35 
36 enum pm_api_cb_id {
37 	PM_INIT_SUSPEND_CB = 30,
38 	PM_ACKNOWLEDGE_CB,
39 	PM_NOTIFY_CB,
40 };
41 
42 static void zynqmp_pm_get_callback_data(u32 *buf)
43 {
44 	zynqmp_pm_invoke_fn(GET_CALLBACK_DATA, 0, 0, 0, 0, buf);
45 }
46 
47 static irqreturn_t zynqmp_pm_isr(int irq, void *data)
48 {
49 	u32 payload[CB_PAYLOAD_SIZE];
50 
51 	zynqmp_pm_get_callback_data(payload);
52 
53 	/* First element is callback API ID, others are callback arguments */
54 	if (payload[0] == PM_INIT_SUSPEND_CB) {
55 		switch (payload[1]) {
56 		case SUSPEND_SYSTEM_SHUTDOWN:
57 			orderly_poweroff(true);
58 			break;
59 		case SUSPEND_POWER_REQUEST:
60 			pm_suspend(PM_SUSPEND_MEM);
61 			break;
62 		default:
63 			pr_err("%s Unsupported InitSuspendCb reason "
64 				"code %d\n", __func__, payload[1]);
65 		}
66 	}
67 
68 	return IRQ_HANDLED;
69 }
70 
71 static ssize_t suspend_mode_show(struct device *dev,
72 				 struct device_attribute *attr, char *buf)
73 {
74 	char *s = buf;
75 	int md;
76 
77 	for (md = PM_SUSPEND_MODE_FIRST; md < ARRAY_SIZE(suspend_modes); md++)
78 		if (suspend_modes[md]) {
79 			if (md == suspend_mode)
80 				s += sprintf(s, "[%s] ", suspend_modes[md]);
81 			else
82 				s += sprintf(s, "%s ", suspend_modes[md]);
83 		}
84 
85 	/* Convert last space to newline */
86 	if (s != buf)
87 		*(s - 1) = '\n';
88 	return (s - buf);
89 }
90 
91 static ssize_t suspend_mode_store(struct device *dev,
92 				  struct device_attribute *attr,
93 				  const char *buf, size_t count)
94 {
95 	int md, ret = -EINVAL;
96 
97 	if (!eemi_ops->set_suspend_mode)
98 		return ret;
99 
100 	for (md = PM_SUSPEND_MODE_FIRST; md < ARRAY_SIZE(suspend_modes); md++)
101 		if (suspend_modes[md] &&
102 		    sysfs_streq(suspend_modes[md], buf)) {
103 			ret = 0;
104 			break;
105 		}
106 
107 	if (!ret && md != suspend_mode) {
108 		ret = eemi_ops->set_suspend_mode(md);
109 		if (likely(!ret))
110 			suspend_mode = md;
111 	}
112 
113 	return ret ? ret : count;
114 }
115 
116 static DEVICE_ATTR_RW(suspend_mode);
117 
118 static int zynqmp_pm_probe(struct platform_device *pdev)
119 {
120 	int ret, irq;
121 	u32 pm_api_version;
122 
123 	eemi_ops = zynqmp_pm_get_eemi_ops();
124 	if (IS_ERR(eemi_ops))
125 		return PTR_ERR(eemi_ops);
126 
127 	if (!eemi_ops->get_api_version || !eemi_ops->init_finalize)
128 		return -ENXIO;
129 
130 	eemi_ops->init_finalize();
131 	eemi_ops->get_api_version(&pm_api_version);
132 
133 	/* Check PM API version number */
134 	if (pm_api_version < ZYNQMP_PM_VERSION)
135 		return -ENODEV;
136 
137 	irq = platform_get_irq(pdev, 0);
138 	if (irq <= 0)
139 		return -ENXIO;
140 
141 	ret = devm_request_threaded_irq(&pdev->dev, irq, NULL, zynqmp_pm_isr,
142 					IRQF_NO_SUSPEND | IRQF_ONESHOT,
143 					dev_name(&pdev->dev), &pdev->dev);
144 	if (ret) {
145 		dev_err(&pdev->dev, "devm_request_threaded_irq '%d' failed "
146 			"with %d\n", irq, ret);
147 		return ret;
148 	}
149 
150 	ret = sysfs_create_file(&pdev->dev.kobj, &dev_attr_suspend_mode.attr);
151 	if (ret) {
152 		dev_err(&pdev->dev, "unable to create sysfs interface\n");
153 		return ret;
154 	}
155 
156 	return 0;
157 }
158 
159 static int zynqmp_pm_remove(struct platform_device *pdev)
160 {
161 	sysfs_remove_file(&pdev->dev.kobj, &dev_attr_suspend_mode.attr);
162 
163 	return 0;
164 }
165 
166 static const struct of_device_id pm_of_match[] = {
167 	{ .compatible = "xlnx,zynqmp-power", },
168 	{ /* end of table */ },
169 };
170 MODULE_DEVICE_TABLE(of, pm_of_match);
171 
172 static struct platform_driver zynqmp_pm_platform_driver = {
173 	.probe = zynqmp_pm_probe,
174 	.remove = zynqmp_pm_remove,
175 	.driver = {
176 		.name = "zynqmp_power",
177 		.of_match_table = pm_of_match,
178 	},
179 };
180 module_platform_driver(zynqmp_pm_platform_driver);
181