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 */
28struct zynqmp_pm_work_struct {
29 struct work_struct callback_work;
30 u32 args[CB_ARG_CNT];
31};
32
33static struct zynqmp_pm_work_struct *zynqmp_pm_init_suspend_work;
34static struct mbox_chan *rx_chan;
35static bool event_registered;
36
37enum 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
45static const char *const suspend_modes[] = {
46 [PM_SUSPEND_MODE_STD] = "standard",
47 [PM_SUSPEND_MODE_POWER_OFF] = "power-off",
48};
49
50static enum pm_suspend_mode suspend_mode = PM_SUSPEND_MODE_STD;
51
52static void zynqmp_pm_get_callback_data(u32 *buf)
53{
54 zynqmp_pm_invoke_fn(GET_CALLBACK_DATA, ret_payload: buf, num_args: 0);
55}
56
57static 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(wq: system_unbound_wq, work: &zynqmp_pm_init_suspend_work->callback_work);
68}
69
70static irqreturn_t zynqmp_pm_isr(int irq, void *data)
71{
72 u32 payload[CB_PAYLOAD_SIZE];
73
74 zynqmp_pm_get_callback_data(buf: 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(force: 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 code %d\n",
87 __func__, payload[1]);
88 }
89 } else {
90 pr_err("%s() Unsupported Callback %d\n", __func__, payload[0]);
91 }
92
93 return IRQ_HANDLED;
94}
95
96static void ipi_receive_callback(struct mbox_client *cl, void *data)
97{
98 struct zynqmp_ipi_message *msg = (struct zynqmp_ipi_message *)data;
99 u32 payload[CB_PAYLOAD_SIZE];
100 int ret;
101
102 memcpy(payload, msg->data, sizeof(msg->len));
103 /* First element is callback API ID, others are callback arguments */
104 if (payload[0] == PM_INIT_SUSPEND_CB) {
105 if (work_pending(&zynqmp_pm_init_suspend_work->callback_work))
106 return;
107
108 /* Copy callback arguments into work's structure */
109 memcpy(zynqmp_pm_init_suspend_work->args, &payload[1],
110 sizeof(zynqmp_pm_init_suspend_work->args));
111
112 queue_work(wq: system_unbound_wq,
113 work: &zynqmp_pm_init_suspend_work->callback_work);
114
115 /* Send NULL message to mbox controller to ack the message */
116 ret = mbox_send_message(chan: rx_chan, NULL);
117 if (ret)
118 pr_err("IPI ack failed. Error %d\n", ret);
119 }
120}
121
122/**
123 * zynqmp_pm_init_suspend_work_fn - Initialize suspend
124 * @work: Pointer to work_struct
125 *
126 * Bottom-half of PM callback IRQ handler.
127 */
128static void zynqmp_pm_init_suspend_work_fn(struct work_struct *work)
129{
130 struct zynqmp_pm_work_struct *pm_work =
131 container_of(work, struct zynqmp_pm_work_struct, callback_work);
132
133 if (pm_work->args[0] == SUSPEND_SYSTEM_SHUTDOWN) {
134 orderly_poweroff(force: true);
135 } else if (pm_work->args[0] == SUSPEND_POWER_REQUEST) {
136 pm_suspend(PM_SUSPEND_MEM);
137 } else {
138 pr_err("%s Unsupported InitSuspendCb reason code %d.\n",
139 __func__, pm_work->args[0]);
140 }
141}
142
143static ssize_t suspend_mode_show(struct device *dev,
144 struct device_attribute *attr, char *buf)
145{
146 char *s = buf;
147 int md;
148
149 for (md = PM_SUSPEND_MODE_FIRST; md < ARRAY_SIZE(suspend_modes); md++)
150 if (suspend_modes[md]) {
151 if (md == suspend_mode)
152 s += sprintf(buf: s, fmt: "[%s] ", suspend_modes[md]);
153 else
154 s += sprintf(buf: s, fmt: "%s ", suspend_modes[md]);
155 }
156
157 /* Convert last space to newline */
158 if (s != buf)
159 *(s - 1) = '\n';
160 return (s - buf);
161}
162
163static ssize_t suspend_mode_store(struct device *dev,
164 struct device_attribute *attr,
165 const char *buf, size_t count)
166{
167 int md, ret = -EINVAL;
168
169 for (md = PM_SUSPEND_MODE_FIRST; md < ARRAY_SIZE(suspend_modes); md++)
170 if (suspend_modes[md] &&
171 sysfs_streq(s1: suspend_modes[md], s2: buf)) {
172 ret = 0;
173 break;
174 }
175
176 if (!ret && md != suspend_mode) {
177 ret = zynqmp_pm_set_suspend_mode(mode: md);
178 if (likely(!ret))
179 suspend_mode = md;
180 }
181
182 return ret ? ret : count;
183}
184
185static DEVICE_ATTR_RW(suspend_mode);
186
187static int zynqmp_pm_probe(struct platform_device *pdev)
188{
189 int ret, irq;
190 u32 pm_api_version;
191 struct mbox_client *client;
192
193 zynqmp_pm_get_api_version(version: &pm_api_version);
194
195 /* Check PM API version number */
196 if (pm_api_version < ZYNQMP_PM_VERSION)
197 return -ENODEV;
198
199 /*
200 * First try to use Xilinx Event Manager by registering suspend_event_callback
201 * for suspend/shutdown event.
202 * If xlnx_register_event() returns -EACCES (Xilinx Event Manager
203 * is not available to use) or -ENODEV(Xilinx Event Manager not compiled),
204 * then use ipi-mailbox or interrupt method.
205 */
206 ret = xlnx_register_event(cb_type: PM_INIT_SUSPEND_CB, node_id: 0, event: 0, wake: false,
207 cb_fun: suspend_event_callback, NULL);
208 if (!ret) {
209 zynqmp_pm_init_suspend_work = devm_kzalloc(dev: &pdev->dev,
210 size: sizeof(struct zynqmp_pm_work_struct),
211 GFP_KERNEL);
212 if (!zynqmp_pm_init_suspend_work) {
213 xlnx_unregister_event(cb_type: PM_INIT_SUSPEND_CB, node_id: 0, event: 0,
214 cb_fun: suspend_event_callback, NULL);
215 return -ENOMEM;
216 }
217 event_registered = true;
218
219 INIT_WORK(&zynqmp_pm_init_suspend_work->callback_work,
220 zynqmp_pm_init_suspend_work_fn);
221 } else if (ret != -EACCES && ret != -ENODEV) {
222 dev_err(&pdev->dev, "Failed to Register with Xilinx Event manager %d\n", ret);
223 return ret;
224 } else if (of_property_present(np: pdev->dev.of_node, propname: "mboxes")) {
225 zynqmp_pm_init_suspend_work =
226 devm_kzalloc(dev: &pdev->dev,
227 size: sizeof(struct zynqmp_pm_work_struct),
228 GFP_KERNEL);
229 if (!zynqmp_pm_init_suspend_work)
230 return -ENOMEM;
231
232 INIT_WORK(&zynqmp_pm_init_suspend_work->callback_work,
233 zynqmp_pm_init_suspend_work_fn);
234 client = devm_kzalloc(dev: &pdev->dev, size: sizeof(*client), GFP_KERNEL);
235 if (!client)
236 return -ENOMEM;
237
238 client->dev = &pdev->dev;
239 client->rx_callback = ipi_receive_callback;
240
241 rx_chan = mbox_request_channel_byname(cl: client, name: "rx");
242 if (IS_ERR(ptr: rx_chan)) {
243 dev_err(&pdev->dev, "Failed to request rx channel\n");
244 return PTR_ERR(ptr: rx_chan);
245 }
246 } else if (of_property_present(np: pdev->dev.of_node, propname: "interrupts")) {
247 irq = platform_get_irq(pdev, 0);
248 if (irq < 0)
249 return irq;
250
251 ret = devm_request_threaded_irq(dev: &pdev->dev, irq, NULL,
252 thread_fn: zynqmp_pm_isr,
253 IRQF_NO_SUSPEND | IRQF_ONESHOT,
254 devname: dev_name(dev: &pdev->dev),
255 dev_id: &pdev->dev);
256 if (ret) {
257 dev_err(&pdev->dev, "devm_request_threaded_irq '%d' failed with %d\n",
258 irq, ret);
259 return ret;
260 }
261 } else {
262 dev_err(&pdev->dev, "Required property not found in DT node\n");
263 return -ENOENT;
264 }
265
266 ret = sysfs_create_file(kobj: &pdev->dev.kobj, attr: &dev_attr_suspend_mode.attr);
267 if (ret) {
268 if (event_registered) {
269 xlnx_unregister_event(cb_type: PM_INIT_SUSPEND_CB, node_id: 0, event: 0, cb_fun: suspend_event_callback,
270 NULL);
271 event_registered = false;
272 }
273 dev_err(&pdev->dev, "unable to create sysfs interface\n");
274 return ret;
275 }
276
277 return 0;
278}
279
280static void zynqmp_pm_remove(struct platform_device *pdev)
281{
282 sysfs_remove_file(kobj: &pdev->dev.kobj, attr: &dev_attr_suspend_mode.attr);
283 if (event_registered)
284 xlnx_unregister_event(cb_type: PM_INIT_SUSPEND_CB, node_id: 0, event: 0, cb_fun: suspend_event_callback, NULL);
285
286 if (!rx_chan)
287 mbox_free_channel(chan: rx_chan);
288}
289
290static const struct of_device_id pm_of_match[] = {
291 { .compatible = "xlnx,zynqmp-power", },
292 { /* end of table */ },
293};
294MODULE_DEVICE_TABLE(of, pm_of_match);
295
296static struct platform_driver zynqmp_pm_platform_driver = {
297 .probe = zynqmp_pm_probe,
298 .remove_new = zynqmp_pm_remove,
299 .driver = {
300 .name = "zynqmp_power",
301 .of_match_table = pm_of_match,
302 },
303};
304module_platform_driver(zynqmp_pm_platform_driver);
305

source code of linux/drivers/soc/xilinx/zynqmp_power.c