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#include <linux/kthread.h>
17
18#include "mei_dev.h"
19#include "hw-me.h"
20#include "hw-me-regs.h"
21
22#include "mei-trace.h"
23
24#define MEI_GSC_RPM_TIMEOUT 500
25
26static int mei_gsc_read_hfs(const struct mei_device *dev, int where, u32 *val)
27{
28 struct mei_me_hw *hw = to_me_hw(dev);
29
30 *val = ioread32(hw->mem_addr + where + 0xC00);
31
32 return 0;
33}
34
35static void mei_gsc_set_ext_op_mem(const struct mei_me_hw *hw, struct resource *mem)
36{
37 u32 low = lower_32_bits(mem->start);
38 u32 hi = upper_32_bits(mem->start);
39 u32 limit = (resource_size(res: mem) / SZ_4K) | GSC_EXT_OP_MEM_VALID;
40
41 iowrite32(low, hw->mem_addr + H_GSC_EXT_OP_MEM_BASE_ADDR_LO_REG);
42 iowrite32(hi, hw->mem_addr + H_GSC_EXT_OP_MEM_BASE_ADDR_HI_REG);
43 iowrite32(limit, hw->mem_addr + H_GSC_EXT_OP_MEM_LIMIT_REG);
44}
45
46static int mei_gsc_probe(struct auxiliary_device *aux_dev,
47 const struct auxiliary_device_id *aux_dev_id)
48{
49 struct mei_aux_device *adev = auxiliary_dev_to_mei_aux_dev(aux_dev);
50 struct mei_device *dev;
51 struct mei_me_hw *hw;
52 struct device *device;
53 const struct mei_cfg *cfg;
54 int ret;
55
56 cfg = mei_me_get_cfg(idx: aux_dev_id->driver_data);
57 if (!cfg)
58 return -ENODEV;
59
60 device = &aux_dev->dev;
61
62 dev = mei_me_dev_init(parent: device, cfg, slow_fw: adev->slow_firmware);
63 if (!dev) {
64 ret = -ENOMEM;
65 goto err;
66 }
67
68 hw = to_me_hw(dev);
69 hw->mem_addr = devm_ioremap_resource(dev: device, res: &adev->bar);
70 if (IS_ERR(ptr: hw->mem_addr)) {
71 ret = PTR_ERR(ptr: hw->mem_addr);
72 goto err;
73 }
74
75 hw->irq = adev->irq;
76 hw->read_fws = mei_gsc_read_hfs;
77
78 dev_set_drvdata(dev: device, data: dev);
79
80 if (adev->ext_op_mem.start) {
81 mei_gsc_set_ext_op_mem(hw, mem: &adev->ext_op_mem);
82 dev->pxp_mode = MEI_DEV_PXP_INIT;
83 }
84
85 /* use polling */
86 if (mei_me_hw_use_polling(hw)) {
87 mei_disable_interrupts(dev);
88 mei_clear_interrupts(dev);
89 init_waitqueue_head(&hw->wait_active);
90 hw->is_active = true; /* start in active mode for initialization */
91 hw->polling_thread = kthread_run(mei_me_polling_thread, dev,
92 "kmegscirqd/%s", dev_name(device));
93 if (IS_ERR(ptr: hw->polling_thread)) {
94 ret = PTR_ERR(ptr: hw->polling_thread);
95 dev_err(device, "unable to create kernel thread: %d\n", ret);
96 goto err;
97 }
98 } else {
99 ret = devm_request_threaded_irq(dev: device, irq: hw->irq,
100 handler: mei_me_irq_quick_handler,
101 thread_fn: mei_me_irq_thread_handler,
102 IRQF_ONESHOT, KBUILD_MODNAME, dev_id: dev);
103 if (ret) {
104 dev_err(device, "irq register failed %d\n", ret);
105 goto err;
106 }
107 }
108
109 pm_runtime_get_noresume(dev: device);
110 pm_runtime_set_active(dev: device);
111 pm_runtime_enable(dev: device);
112
113 /* Continue to char device setup in spite of firmware handshake failure.
114 * In order to provide access to the firmware status registers to the user
115 * space via sysfs.
116 */
117 if (mei_start(dev))
118 dev_warn(device, "init hw failure.\n");
119
120 pm_runtime_set_autosuspend_delay(dev: device, MEI_GSC_RPM_TIMEOUT);
121 pm_runtime_use_autosuspend(dev: device);
122
123 ret = mei_register(dev, parent: device);
124 if (ret)
125 goto register_err;
126
127 pm_runtime_put_noidle(dev: device);
128 return 0;
129
130register_err:
131 mei_stop(dev);
132 if (!mei_me_hw_use_polling(hw))
133 devm_free_irq(dev: device, irq: hw->irq, dev_id: dev);
134
135err:
136 dev_err(device, "probe failed: %d\n", ret);
137 dev_set_drvdata(dev: device, NULL);
138 return ret;
139}
140
141static void mei_gsc_remove(struct auxiliary_device *aux_dev)
142{
143 struct mei_device *dev;
144 struct mei_me_hw *hw;
145
146 dev = dev_get_drvdata(dev: &aux_dev->dev);
147 hw = to_me_hw(dev);
148
149 mei_stop(dev);
150
151 hw = to_me_hw(dev);
152 if (mei_me_hw_use_polling(hw))
153 kthread_stop(k: hw->polling_thread);
154
155 mei_deregister(dev);
156
157 pm_runtime_disable(dev: &aux_dev->dev);
158
159 mei_disable_interrupts(dev);
160 if (!mei_me_hw_use_polling(hw))
161 devm_free_irq(dev: &aux_dev->dev, irq: hw->irq, dev_id: dev);
162}
163
164static int __maybe_unused mei_gsc_pm_suspend(struct device *device)
165{
166 struct mei_device *dev = dev_get_drvdata(dev: device);
167
168 mei_stop(dev);
169
170 mei_disable_interrupts(dev);
171
172 return 0;
173}
174
175static int __maybe_unused mei_gsc_pm_resume(struct device *device)
176{
177 struct mei_device *dev = dev_get_drvdata(dev: device);
178 struct auxiliary_device *aux_dev;
179 struct mei_aux_device *adev;
180 int err;
181 struct mei_me_hw *hw;
182
183 hw = to_me_hw(dev);
184 aux_dev = to_auxiliary_dev(dev: device);
185 adev = auxiliary_dev_to_mei_aux_dev(aux_dev);
186 if (adev->ext_op_mem.start) {
187 mei_gsc_set_ext_op_mem(hw, mem: &adev->ext_op_mem);
188 dev->pxp_mode = MEI_DEV_PXP_INIT;
189 }
190
191 err = mei_restart(dev);
192 if (err)
193 return err;
194
195 /* Start timer if stopped in suspend */
196 schedule_delayed_work(dwork: &dev->timer_work, HZ);
197
198 return 0;
199}
200
201static int __maybe_unused mei_gsc_pm_runtime_idle(struct device *device)
202{
203 struct mei_device *dev = dev_get_drvdata(dev: device);
204
205 if (mei_write_is_idle(dev))
206 pm_runtime_autosuspend(dev: device);
207
208 return -EBUSY;
209}
210
211static int __maybe_unused mei_gsc_pm_runtime_suspend(struct device *device)
212{
213 struct mei_device *dev = dev_get_drvdata(dev: device);
214 struct mei_me_hw *hw;
215 int ret;
216
217 mutex_lock(&dev->device_lock);
218
219 if (mei_write_is_idle(dev)) {
220 hw = to_me_hw(dev);
221 hw->pg_state = MEI_PG_ON;
222
223 if (mei_me_hw_use_polling(hw))
224 hw->is_active = false;
225 ret = 0;
226 } else {
227 ret = -EAGAIN;
228 }
229
230 mutex_unlock(lock: &dev->device_lock);
231
232 return ret;
233}
234
235static int __maybe_unused mei_gsc_pm_runtime_resume(struct device *device)
236{
237 struct mei_device *dev = dev_get_drvdata(dev: device);
238 struct mei_me_hw *hw;
239 irqreturn_t irq_ret;
240
241 mutex_lock(&dev->device_lock);
242
243 hw = to_me_hw(dev);
244 hw->pg_state = MEI_PG_OFF;
245
246 if (mei_me_hw_use_polling(hw)) {
247 hw->is_active = true;
248 wake_up(&hw->wait_active);
249 }
250
251 mutex_unlock(lock: &dev->device_lock);
252
253 irq_ret = mei_me_irq_thread_handler(irq: 1, dev_id: dev);
254 if (irq_ret != IRQ_HANDLED)
255 dev_err(dev->dev, "thread handler fail %d\n", irq_ret);
256
257 return 0;
258}
259
260static const struct dev_pm_ops mei_gsc_pm_ops = {
261 SET_SYSTEM_SLEEP_PM_OPS(mei_gsc_pm_suspend,
262 mei_gsc_pm_resume)
263 SET_RUNTIME_PM_OPS(mei_gsc_pm_runtime_suspend,
264 mei_gsc_pm_runtime_resume,
265 mei_gsc_pm_runtime_idle)
266};
267
268static const struct auxiliary_device_id mei_gsc_id_table[] = {
269 {
270 .name = "i915.mei-gsc",
271 .driver_data = MEI_ME_GSC_CFG,
272
273 },
274 {
275 .name = "i915.mei-gscfi",
276 .driver_data = MEI_ME_GSCFI_CFG,
277 },
278 {
279 .name = "xe.mei-gscfi",
280 .driver_data = MEI_ME_GSCFI_CFG,
281 },
282 {
283 /* sentinel */
284 }
285};
286MODULE_DEVICE_TABLE(auxiliary, mei_gsc_id_table);
287
288static struct auxiliary_driver mei_gsc_driver = {
289 .probe = mei_gsc_probe,
290 .remove = mei_gsc_remove,
291 .driver = {
292 /* auxiliary_driver_register() sets .name to be the modname */
293 .pm = &mei_gsc_pm_ops,
294 },
295 .id_table = mei_gsc_id_table
296};
297module_auxiliary_driver(mei_gsc_driver);
298
299MODULE_AUTHOR("Intel Corporation");
300MODULE_ALIAS("auxiliary:i915.mei-gsc");
301MODULE_ALIAS("auxiliary:i915.mei-gscfi");
302MODULE_ALIAS("auxiliary:xe.mei-gscfi");
303MODULE_DESCRIPTION("Intel(R) Graphics System Controller");
304MODULE_LICENSE("GPL");
305

source code of linux/drivers/misc/mei/gsc-me.c