xref: /openbmc/linux/drivers/acpi/pfr_telemetry.c (revision 55eb9a6c)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * ACPI Platform Firmware Runtime Telemetry driver
4  *
5  * Copyright (C) 2021 Intel Corporation
6  * Author: Chen Yu <yu.c.chen@intel.com>
7  *
8  * This driver allows user space to fetch telemetry data from the
9  * firmware with the help of the Platform Firmware Runtime Telemetry
10  * interface.
11  */
12 #include <linux/acpi.h>
13 #include <linux/device.h>
14 #include <linux/err.h>
15 #include <linux/errno.h>
16 #include <linux/file.h>
17 #include <linux/fs.h>
18 #include <linux/miscdevice.h>
19 #include <linux/module.h>
20 #include <linux/mm.h>
21 #include <linux/platform_device.h>
22 #include <linux/string.h>
23 #include <linux/uaccess.h>
24 #include <linux/uio.h>
25 #include <linux/uuid.h>
26 
27 #include <uapi/linux/pfrut.h>
28 
29 #define PFRT_LOG_EXEC_IDX	0
30 #define PFRT_LOG_HISTORY_IDX	1
31 
32 #define PFRT_LOG_ERR		0
33 #define PFRT_LOG_WARN	1
34 #define PFRT_LOG_INFO	2
35 #define PFRT_LOG_VERB	4
36 
37 #define PFRT_FUNC_SET_LEV		1
38 #define PFRT_FUNC_GET_LEV		2
39 #define PFRT_FUNC_GET_DATA		3
40 
41 #define PFRT_REVID_1		1
42 #define PFRT_REVID_2		2
43 #define PFRT_DEFAULT_REV_ID	PFRT_REVID_1
44 
45 enum log_index {
46 	LOG_STATUS_IDX = 0,
47 	LOG_EXT_STATUS_IDX = 1,
48 	LOG_MAX_SZ_IDX = 2,
49 	LOG_CHUNK1_LO_IDX = 3,
50 	LOG_CHUNK1_HI_IDX = 4,
51 	LOG_CHUNK1_SZ_IDX = 5,
52 	LOG_CHUNK2_LO_IDX = 6,
53 	LOG_CHUNK2_HI_IDX = 7,
54 	LOG_CHUNK2_SZ_IDX = 8,
55 	LOG_ROLLOVER_CNT_IDX = 9,
56 	LOG_RESET_CNT_IDX = 10,
57 	LOG_NR_IDX
58 };
59 
60 struct pfrt_log_device {
61 	int index;
62 	struct pfrt_log_info info;
63 	struct device *parent_dev;
64 	struct miscdevice miscdev;
65 };
66 
67 /* pfrt_guid is the parameter for _DSM method */
68 static const guid_t pfrt_log_guid =
69 	GUID_INIT(0x75191659, 0x8178, 0x4D9D, 0xB8, 0x8F, 0xAC, 0x5E,
70 		  0x5E, 0x93, 0xE8, 0xBF);
71 
72 static DEFINE_IDA(pfrt_log_ida);
73 
74 static inline struct pfrt_log_device *to_pfrt_log_dev(struct file *file)
75 {
76 	return container_of(file->private_data, struct pfrt_log_device, miscdev);
77 }
78 
79 static int get_pfrt_log_data_info(struct pfrt_log_data_info *data_info,
80 				  struct pfrt_log_device *pfrt_log_dev)
81 {
82 	acpi_handle handle = ACPI_HANDLE(pfrt_log_dev->parent_dev);
83 	union acpi_object *out_obj, in_obj, in_buf;
84 	int ret = -EBUSY;
85 
86 	memset(data_info, 0, sizeof(*data_info));
87 	memset(&in_obj, 0, sizeof(in_obj));
88 	memset(&in_buf, 0, sizeof(in_buf));
89 	in_obj.type = ACPI_TYPE_PACKAGE;
90 	in_obj.package.count = 1;
91 	in_obj.package.elements = &in_buf;
92 	in_buf.type = ACPI_TYPE_INTEGER;
93 	in_buf.integer.value = pfrt_log_dev->info.log_type;
94 
95 	out_obj = acpi_evaluate_dsm_typed(handle, &pfrt_log_guid,
96 					  pfrt_log_dev->info.log_revid, PFRT_FUNC_GET_DATA,
97 					  &in_obj, ACPI_TYPE_PACKAGE);
98 	if (!out_obj)
99 		return -EINVAL;
100 
101 	if (out_obj->package.count < LOG_NR_IDX ||
102 	    out_obj->package.elements[LOG_STATUS_IDX].type != ACPI_TYPE_INTEGER ||
103 	    out_obj->package.elements[LOG_EXT_STATUS_IDX].type != ACPI_TYPE_INTEGER ||
104 	    out_obj->package.elements[LOG_MAX_SZ_IDX].type != ACPI_TYPE_INTEGER ||
105 	    out_obj->package.elements[LOG_CHUNK1_LO_IDX].type != ACPI_TYPE_INTEGER ||
106 	    out_obj->package.elements[LOG_CHUNK1_HI_IDX].type != ACPI_TYPE_INTEGER ||
107 	    out_obj->package.elements[LOG_CHUNK1_SZ_IDX].type != ACPI_TYPE_INTEGER ||
108 	    out_obj->package.elements[LOG_CHUNK2_LO_IDX].type != ACPI_TYPE_INTEGER ||
109 	    out_obj->package.elements[LOG_CHUNK2_HI_IDX].type != ACPI_TYPE_INTEGER ||
110 	    out_obj->package.elements[LOG_CHUNK2_SZ_IDX].type != ACPI_TYPE_INTEGER ||
111 	    out_obj->package.elements[LOG_ROLLOVER_CNT_IDX].type != ACPI_TYPE_INTEGER ||
112 	    out_obj->package.elements[LOG_RESET_CNT_IDX].type != ACPI_TYPE_INTEGER)
113 		goto free_acpi_buffer;
114 
115 	data_info->status = out_obj->package.elements[LOG_STATUS_IDX].integer.value;
116 	data_info->ext_status =
117 		out_obj->package.elements[LOG_EXT_STATUS_IDX].integer.value;
118 	if (data_info->status != DSM_SUCCEED) {
119 		dev_dbg(pfrt_log_dev->parent_dev, "Error Status:%d\n", data_info->status);
120 		dev_dbg(pfrt_log_dev->parent_dev, "Error Extend Status:%d\n",
121 			data_info->ext_status);
122 		goto free_acpi_buffer;
123 	}
124 
125 	data_info->max_data_size =
126 		out_obj->package.elements[LOG_MAX_SZ_IDX].integer.value;
127 	data_info->chunk1_addr_lo =
128 		out_obj->package.elements[LOG_CHUNK1_LO_IDX].integer.value;
129 	data_info->chunk1_addr_hi =
130 		out_obj->package.elements[LOG_CHUNK1_HI_IDX].integer.value;
131 	data_info->chunk1_size =
132 		out_obj->package.elements[LOG_CHUNK1_SZ_IDX].integer.value;
133 	data_info->chunk2_addr_lo =
134 		out_obj->package.elements[LOG_CHUNK2_LO_IDX].integer.value;
135 	data_info->chunk2_addr_hi =
136 		out_obj->package.elements[LOG_CHUNK2_HI_IDX].integer.value;
137 	data_info->chunk2_size =
138 		out_obj->package.elements[LOG_CHUNK2_SZ_IDX].integer.value;
139 	data_info->rollover_cnt =
140 		out_obj->package.elements[LOG_ROLLOVER_CNT_IDX].integer.value;
141 	data_info->reset_cnt =
142 		out_obj->package.elements[LOG_RESET_CNT_IDX].integer.value;
143 
144 	ret = 0;
145 
146 free_acpi_buffer:
147 	kfree(out_obj);
148 
149 	return ret;
150 }
151 
152 static int set_pfrt_log_level(int level, struct pfrt_log_device *pfrt_log_dev)
153 {
154 	acpi_handle handle = ACPI_HANDLE(pfrt_log_dev->parent_dev);
155 	union acpi_object *out_obj, *obj, in_obj, in_buf;
156 	enum pfru_dsm_status status, ext_status;
157 	int ret = 0;
158 
159 	memset(&in_obj, 0, sizeof(in_obj));
160 	memset(&in_buf, 0, sizeof(in_buf));
161 	in_obj.type = ACPI_TYPE_PACKAGE;
162 	in_obj.package.count = 1;
163 	in_obj.package.elements = &in_buf;
164 	in_buf.type = ACPI_TYPE_INTEGER;
165 	in_buf.integer.value = level;
166 
167 	out_obj = acpi_evaluate_dsm_typed(handle, &pfrt_log_guid,
168 					  pfrt_log_dev->info.log_revid, PFRT_FUNC_SET_LEV,
169 					  &in_obj, ACPI_TYPE_PACKAGE);
170 	if (!out_obj)
171 		return -EINVAL;
172 
173 	obj = &out_obj->package.elements[0];
174 	status = obj->integer.value;
175 	if (status != DSM_SUCCEED) {
176 		obj = &out_obj->package.elements[1];
177 		ext_status = obj->integer.value;
178 		dev_dbg(pfrt_log_dev->parent_dev, "Error Status:%d\n", status);
179 		dev_dbg(pfrt_log_dev->parent_dev, "Error Extend Status:%d\n", ext_status);
180 		ret = -EBUSY;
181 	}
182 
183 	kfree(out_obj);
184 
185 	return ret;
186 }
187 
188 static int get_pfrt_log_level(struct pfrt_log_device *pfrt_log_dev)
189 {
190 	acpi_handle handle = ACPI_HANDLE(pfrt_log_dev->parent_dev);
191 	union acpi_object *out_obj, *obj;
192 	enum pfru_dsm_status status, ext_status;
193 	int ret = -EBUSY;
194 
195 	out_obj = acpi_evaluate_dsm_typed(handle, &pfrt_log_guid,
196 					  pfrt_log_dev->info.log_revid, PFRT_FUNC_GET_LEV,
197 					  NULL, ACPI_TYPE_PACKAGE);
198 	if (!out_obj)
199 		return -EINVAL;
200 
201 	obj = &out_obj->package.elements[0];
202 	if (obj->type != ACPI_TYPE_INTEGER)
203 		goto free_acpi_buffer;
204 
205 	status = obj->integer.value;
206 	if (status != DSM_SUCCEED) {
207 		obj = &out_obj->package.elements[1];
208 		ext_status = obj->integer.value;
209 		dev_dbg(pfrt_log_dev->parent_dev, "Error Status:%d\n", status);
210 		dev_dbg(pfrt_log_dev->parent_dev, "Error Extend Status:%d\n", ext_status);
211 		goto free_acpi_buffer;
212 	}
213 
214 	obj = &out_obj->package.elements[2];
215 	if (obj->type != ACPI_TYPE_INTEGER)
216 		goto free_acpi_buffer;
217 
218 	ret = obj->integer.value;
219 
220 free_acpi_buffer:
221 	kfree(out_obj);
222 
223 	return ret;
224 }
225 
226 static int valid_log_level(u32 level)
227 {
228 	return level == PFRT_LOG_ERR || level == PFRT_LOG_WARN ||
229 	       level == PFRT_LOG_INFO || level == PFRT_LOG_VERB;
230 }
231 
232 static int valid_log_type(u32 type)
233 {
234 	return type == PFRT_LOG_EXEC_IDX || type == PFRT_LOG_HISTORY_IDX;
235 }
236 
237 static inline int valid_log_revid(u32 id)
238 {
239 	return id == PFRT_REVID_1 || id == PFRT_REVID_2;
240 }
241 
242 static long pfrt_log_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
243 {
244 	struct pfrt_log_device *pfrt_log_dev = to_pfrt_log_dev(file);
245 	struct pfrt_log_data_info data_info;
246 	struct pfrt_log_info info;
247 	void __user *p;
248 	int ret = 0;
249 
250 	p = (void __user *)arg;
251 
252 	switch (cmd) {
253 	case PFRT_LOG_IOC_SET_INFO:
254 		if (copy_from_user(&info, p, sizeof(info)))
255 			return -EFAULT;
256 
257 		if (valid_log_revid(info.log_revid))
258 			pfrt_log_dev->info.log_revid = info.log_revid;
259 
260 		if (valid_log_level(info.log_level)) {
261 			ret = set_pfrt_log_level(info.log_level, pfrt_log_dev);
262 			if (ret < 0)
263 				return ret;
264 
265 			pfrt_log_dev->info.log_level = info.log_level;
266 		}
267 
268 		if (valid_log_type(info.log_type))
269 			pfrt_log_dev->info.log_type = info.log_type;
270 
271 		return 0;
272 
273 	case PFRT_LOG_IOC_GET_INFO:
274 		info.log_level = get_pfrt_log_level(pfrt_log_dev);
275 		if (ret < 0)
276 			return ret;
277 
278 		info.log_type = pfrt_log_dev->info.log_type;
279 		info.log_revid = pfrt_log_dev->info.log_revid;
280 		if (copy_to_user(p, &info, sizeof(info)))
281 			return -EFAULT;
282 
283 		return 0;
284 
285 	case PFRT_LOG_IOC_GET_DATA_INFO:
286 		ret = get_pfrt_log_data_info(&data_info, pfrt_log_dev);
287 		if (ret)
288 			return ret;
289 
290 		if (copy_to_user(p, &data_info, sizeof(struct pfrt_log_data_info)))
291 			return -EFAULT;
292 
293 		return 0;
294 
295 	default:
296 		return -ENOTTY;
297 	}
298 }
299 
300 static int
301 pfrt_log_mmap(struct file *file, struct vm_area_struct *vma)
302 {
303 	struct pfrt_log_device *pfrt_log_dev;
304 	struct pfrt_log_data_info info;
305 	unsigned long psize, vsize;
306 	phys_addr_t base_addr;
307 	int ret;
308 
309 	if (vma->vm_flags & VM_WRITE)
310 		return -EROFS;
311 
312 	/* changing from read to write with mprotect is not allowed */
313 	vma->vm_flags &= ~VM_MAYWRITE;
314 
315 	pfrt_log_dev = to_pfrt_log_dev(file);
316 
317 	ret = get_pfrt_log_data_info(&info, pfrt_log_dev);
318 	if (ret)
319 		return ret;
320 
321 	base_addr = (phys_addr_t)((info.chunk2_addr_hi << 32) | info.chunk2_addr_lo);
322 	/* pfrt update has not been launched yet */
323 	if (!base_addr)
324 		return -ENODEV;
325 
326 	psize = info.max_data_size;
327 	/* base address and total buffer size must be page aligned */
328 	if (!PAGE_ALIGNED(base_addr) || !PAGE_ALIGNED(psize))
329 		return -ENODEV;
330 
331 	vsize = vma->vm_end - vma->vm_start;
332 	if (vsize > psize)
333 		return -EINVAL;
334 
335 	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
336 	if (io_remap_pfn_range(vma, vma->vm_start, PFN_DOWN(base_addr),
337 			       vsize, vma->vm_page_prot))
338 		return -EAGAIN;
339 
340 	return 0;
341 }
342 
343 static const struct file_operations acpi_pfrt_log_fops = {
344 	.owner		= THIS_MODULE,
345 	.mmap		= pfrt_log_mmap,
346 	.unlocked_ioctl = pfrt_log_ioctl,
347 	.llseek		= noop_llseek,
348 };
349 
350 static int acpi_pfrt_log_remove(struct platform_device *pdev)
351 {
352 	struct pfrt_log_device *pfrt_log_dev = platform_get_drvdata(pdev);
353 
354 	misc_deregister(&pfrt_log_dev->miscdev);
355 
356 	return 0;
357 }
358 
359 static void pfrt_log_put_idx(void *data)
360 {
361 	struct pfrt_log_device *pfrt_log_dev = data;
362 
363 	ida_free(&pfrt_log_ida, pfrt_log_dev->index);
364 }
365 
366 static int acpi_pfrt_log_probe(struct platform_device *pdev)
367 {
368 	acpi_handle handle = ACPI_HANDLE(&pdev->dev);
369 	struct pfrt_log_device *pfrt_log_dev;
370 	int ret;
371 
372 	if (!acpi_has_method(handle, "_DSM")) {
373 		dev_dbg(&pdev->dev, "Missing _DSM\n");
374 		return -ENODEV;
375 	}
376 
377 	pfrt_log_dev = devm_kzalloc(&pdev->dev, sizeof(*pfrt_log_dev), GFP_KERNEL);
378 	if (!pfrt_log_dev)
379 		return -ENOMEM;
380 
381 	ret = ida_alloc(&pfrt_log_ida, GFP_KERNEL);
382 	if (ret < 0)
383 		return ret;
384 
385 	pfrt_log_dev->index = ret;
386 	ret = devm_add_action_or_reset(&pdev->dev, pfrt_log_put_idx, pfrt_log_dev);
387 	if (ret)
388 		return ret;
389 
390 	pfrt_log_dev->info.log_revid = PFRT_DEFAULT_REV_ID;
391 	pfrt_log_dev->parent_dev = &pdev->dev;
392 
393 	pfrt_log_dev->miscdev.minor = MISC_DYNAMIC_MINOR;
394 	pfrt_log_dev->miscdev.name = devm_kasprintf(&pdev->dev, GFP_KERNEL,
395 						    "pfrt%d",
396 						    pfrt_log_dev->index);
397 	if (!pfrt_log_dev->miscdev.name)
398 		return -ENOMEM;
399 
400 	pfrt_log_dev->miscdev.nodename = devm_kasprintf(&pdev->dev, GFP_KERNEL,
401 							"acpi_pfr_telemetry%d",
402 							pfrt_log_dev->index);
403 	if (!pfrt_log_dev->miscdev.nodename)
404 		return -ENOMEM;
405 
406 	pfrt_log_dev->miscdev.fops = &acpi_pfrt_log_fops;
407 	pfrt_log_dev->miscdev.parent = &pdev->dev;
408 
409 	ret = misc_register(&pfrt_log_dev->miscdev);
410 	if (ret)
411 		return ret;
412 
413 	platform_set_drvdata(pdev, pfrt_log_dev);
414 
415 	return 0;
416 }
417 
418 static const struct acpi_device_id acpi_pfrt_log_ids[] = {
419 	{"INTC1081"},
420 	{}
421 };
422 MODULE_DEVICE_TABLE(acpi, acpi_pfrt_log_ids);
423 
424 static struct platform_driver acpi_pfrt_log_driver = {
425 	.driver = {
426 		.name = "pfr_telemetry",
427 		.acpi_match_table = acpi_pfrt_log_ids,
428 	},
429 	.probe = acpi_pfrt_log_probe,
430 	.remove = acpi_pfrt_log_remove,
431 };
432 module_platform_driver(acpi_pfrt_log_driver);
433 
434 MODULE_DESCRIPTION("Platform Firmware Runtime Update Telemetry driver");
435 MODULE_LICENSE("GPL v2");
436