xref: /linux/drivers/misc/mei/gsc-me.c (revision b5bee6ced21ca98389000b7017dd41b0cc37fa50)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright(c) 2019-2022, Intel Corporation. All rights reserved.
4  *
5  * Intel Management Engine Interface (Intel MEI) Linux driver
6  */
7 
8 #include <linux/module.h>
9 #include <linux/mei_aux.h>
10 #include <linux/device.h>
11 #include <linux/irqreturn.h>
12 #include <linux/jiffies.h>
13 #include <linux/ktime.h>
14 #include <linux/delay.h>
15 #include <linux/pm_runtime.h>
16 
17 #include "mei_dev.h"
18 #include "hw-me.h"
19 #include "hw-me-regs.h"
20 
21 #include "mei-trace.h"
22 
23 #define MEI_GSC_RPM_TIMEOUT 500
24 
25 static int mei_gsc_read_hfs(const struct mei_device *dev, int where, u32 *val)
26 {
27 	struct mei_me_hw *hw = to_me_hw(dev);
28 
29 	*val = ioread32(hw->mem_addr + where + 0xC00);
30 
31 	return 0;
32 }
33 
34 static int mei_gsc_probe(struct auxiliary_device *aux_dev,
35 			 const struct auxiliary_device_id *aux_dev_id)
36 {
37 	struct mei_aux_device *adev = auxiliary_dev_to_mei_aux_dev(aux_dev);
38 	struct mei_device *dev;
39 	struct mei_me_hw *hw;
40 	struct device *device;
41 	const struct mei_cfg *cfg;
42 	int ret;
43 
44 	cfg = mei_me_get_cfg(aux_dev_id->driver_data);
45 	if (!cfg)
46 		return -ENODEV;
47 
48 	device = &aux_dev->dev;
49 
50 	dev = mei_me_dev_init(device, cfg);
51 	if (!dev) {
52 		ret = -ENOMEM;
53 		goto err;
54 	}
55 
56 	hw = to_me_hw(dev);
57 	hw->mem_addr = devm_ioremap_resource(device, &adev->bar);
58 	if (IS_ERR(hw->mem_addr)) {
59 		ret = PTR_ERR(hw->mem_addr);
60 		goto err;
61 	}
62 
63 	hw->irq = adev->irq;
64 	hw->read_fws = mei_gsc_read_hfs;
65 
66 	dev_set_drvdata(device, dev);
67 
68 	ret = devm_request_threaded_irq(device, hw->irq,
69 					mei_me_irq_quick_handler,
70 					mei_me_irq_thread_handler,
71 					IRQF_ONESHOT, KBUILD_MODNAME, dev);
72 	if (ret) {
73 		dev_err(device, "irq register failed %d\n", ret);
74 		goto err;
75 	}
76 
77 	pm_runtime_get_noresume(device);
78 	pm_runtime_set_active(device);
79 	pm_runtime_enable(device);
80 
81 	/* Continue to char device setup in spite of firmware handshake failure.
82 	 * In order to provide access to the firmware status registers to the user
83 	 * space via sysfs.
84 	 */
85 	if (mei_start(dev))
86 		dev_warn(device, "init hw failure.\n");
87 
88 	pm_runtime_set_autosuspend_delay(device, MEI_GSC_RPM_TIMEOUT);
89 	pm_runtime_use_autosuspend(device);
90 
91 	ret = mei_register(dev, device);
92 	if (ret)
93 		goto register_err;
94 
95 	pm_runtime_put_noidle(device);
96 	return 0;
97 
98 register_err:
99 	mei_stop(dev);
100 	devm_free_irq(device, hw->irq, dev);
101 
102 err:
103 	dev_err(device, "probe failed: %d\n", ret);
104 	dev_set_drvdata(device, NULL);
105 	return ret;
106 }
107 
108 static void mei_gsc_remove(struct auxiliary_device *aux_dev)
109 {
110 	struct mei_device *dev;
111 	struct mei_me_hw *hw;
112 
113 	dev = dev_get_drvdata(&aux_dev->dev);
114 	if (!dev)
115 		return;
116 
117 	hw = to_me_hw(dev);
118 
119 	mei_stop(dev);
120 
121 	mei_deregister(dev);
122 
123 	pm_runtime_disable(&aux_dev->dev);
124 
125 	mei_disable_interrupts(dev);
126 	devm_free_irq(&aux_dev->dev, hw->irq, dev);
127 }
128 
129 static int __maybe_unused mei_gsc_pm_suspend(struct device *device)
130 {
131 	struct mei_device *dev = dev_get_drvdata(device);
132 
133 	if (!dev)
134 		return -ENODEV;
135 
136 	mei_stop(dev);
137 
138 	mei_disable_interrupts(dev);
139 
140 	return 0;
141 }
142 
143 static int __maybe_unused mei_gsc_pm_resume(struct device *device)
144 {
145 	struct mei_device *dev = dev_get_drvdata(device);
146 	int err;
147 
148 	if (!dev)
149 		return -ENODEV;
150 
151 	err = mei_restart(dev);
152 	if (err)
153 		return err;
154 
155 	/* Start timer if stopped in suspend */
156 	schedule_delayed_work(&dev->timer_work, HZ);
157 
158 	return 0;
159 }
160 
161 static int __maybe_unused mei_gsc_pm_runtime_idle(struct device *device)
162 {
163 	struct mei_device *dev = dev_get_drvdata(device);
164 
165 	if (!dev)
166 		return -ENODEV;
167 	if (mei_write_is_idle(dev))
168 		pm_runtime_autosuspend(device);
169 
170 	return -EBUSY;
171 }
172 
173 static int  __maybe_unused mei_gsc_pm_runtime_suspend(struct device *device)
174 {
175 	struct mei_device *dev = dev_get_drvdata(device);
176 	struct mei_me_hw *hw;
177 	int ret;
178 
179 	if (!dev)
180 		return -ENODEV;
181 
182 	mutex_lock(&dev->device_lock);
183 
184 	if (mei_write_is_idle(dev)) {
185 		hw = to_me_hw(dev);
186 		hw->pg_state = MEI_PG_ON;
187 		ret = 0;
188 	} else {
189 		ret = -EAGAIN;
190 	}
191 
192 	mutex_unlock(&dev->device_lock);
193 
194 	return ret;
195 }
196 
197 static int __maybe_unused mei_gsc_pm_runtime_resume(struct device *device)
198 {
199 	struct mei_device *dev = dev_get_drvdata(device);
200 	struct mei_me_hw *hw;
201 	irqreturn_t irq_ret;
202 
203 	if (!dev)
204 		return -ENODEV;
205 
206 	mutex_lock(&dev->device_lock);
207 
208 	hw = to_me_hw(dev);
209 	hw->pg_state = MEI_PG_OFF;
210 
211 	mutex_unlock(&dev->device_lock);
212 
213 	irq_ret = mei_me_irq_thread_handler(1, dev);
214 	if (irq_ret != IRQ_HANDLED)
215 		dev_err(dev->dev, "thread handler fail %d\n", irq_ret);
216 
217 	return 0;
218 }
219 
220 static const struct dev_pm_ops mei_gsc_pm_ops = {
221 	SET_SYSTEM_SLEEP_PM_OPS(mei_gsc_pm_suspend,
222 				mei_gsc_pm_resume)
223 	SET_RUNTIME_PM_OPS(mei_gsc_pm_runtime_suspend,
224 			   mei_gsc_pm_runtime_resume,
225 			   mei_gsc_pm_runtime_idle)
226 };
227 
228 static const struct auxiliary_device_id mei_gsc_id_table[] = {
229 	{
230 		.name = "i915.mei-gsc",
231 		.driver_data = MEI_ME_GSC_CFG,
232 
233 	},
234 	{
235 		.name = "i915.mei-gscfi",
236 		.driver_data = MEI_ME_GSCFI_CFG,
237 	},
238 	{
239 		/* sentinel */
240 	}
241 };
242 MODULE_DEVICE_TABLE(auxiliary, mei_gsc_id_table);
243 
244 static struct auxiliary_driver mei_gsc_driver = {
245 	.probe	= mei_gsc_probe,
246 	.remove = mei_gsc_remove,
247 	.driver = {
248 		/* auxiliary_driver_register() sets .name to be the modname */
249 		.pm = &mei_gsc_pm_ops,
250 	},
251 	.id_table = mei_gsc_id_table
252 };
253 module_auxiliary_driver(mei_gsc_driver);
254 
255 MODULE_AUTHOR("Intel Corporation");
256 MODULE_ALIAS("auxiliary:i915.mei-gsc");
257 MODULE_ALIAS("auxiliary:i915.mei-gscfi");
258 MODULE_LICENSE("GPL");
259