1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Remote Processor Framework
4 *
5 * Copyright (C) 2011 Texas Instruments, Inc.
6 * Copyright (C) 2011 Google, Inc.
7 *
8 * Ohad Ben-Cohen <ohad@wizery.com>
9 * Mark Grosen <mgrosen@ti.com>
10 * Brian Swetland <swetland@google.com>
11 * Fernando Guzman Lugo <fernando.lugo@ti.com>
12 * Suman Anna <s-anna@ti.com>
13 * Robert Tivy <rtivy@ti.com>
14 * Armando Uribe De Leon <x0095078@ti.com>
15 */
16
17 #define pr_fmt(fmt) "%s: " fmt, __func__
18
19 #include <linux/kernel.h>
20 #include <linux/debugfs.h>
21 #include <linux/remoteproc.h>
22 #include <linux/device.h>
23 #include <linux/uaccess.h>
24
25 #include "remoteproc_internal.h"
26
27 /* remoteproc debugfs parent dir */
28 static struct dentry *rproc_dbg;
29
30 /*
31 * A coredump-configuration-to-string lookup table, for exposing a
32 * human readable configuration via debugfs. Always keep in sync with
33 * enum rproc_coredump_mechanism
34 */
35 static const char * const rproc_coredump_str[] = {
36 [RPROC_COREDUMP_DISABLED] = "disabled",
37 [RPROC_COREDUMP_ENABLED] = "enabled",
38 [RPROC_COREDUMP_INLINE] = "inline",
39 };
40
41 /* Expose the current coredump configuration via debugfs */
rproc_coredump_read(struct file * filp,char __user * userbuf,size_t count,loff_t * ppos)42 static ssize_t rproc_coredump_read(struct file *filp, char __user *userbuf,
43 size_t count, loff_t *ppos)
44 {
45 struct rproc *rproc = filp->private_data;
46 char buf[20];
47 int len;
48
49 len = scnprintf(buf, sizeof(buf), "%s\n",
50 rproc_coredump_str[rproc->dump_conf]);
51
52 return simple_read_from_buffer(userbuf, count, ppos, buf, len);
53 }
54
55 /*
56 * By writing to the 'coredump' debugfs entry, we control the behavior of the
57 * coredump mechanism dynamically. The default value of this entry is "disabled".
58 *
59 * The 'coredump' debugfs entry supports these commands:
60 *
61 * disabled: By default coredump collection is disabled. Recovery will
62 * proceed without collecting any dump.
63 *
64 * enabled: When the remoteproc crashes the entire coredump will be copied
65 * to a separate buffer and exposed to userspace.
66 *
67 * inline: The coredump will not be copied to a separate buffer and the
68 * recovery process will have to wait until data is read by
69 * userspace. But this avoid usage of extra memory.
70 */
rproc_coredump_write(struct file * filp,const char __user * user_buf,size_t count,loff_t * ppos)71 static ssize_t rproc_coredump_write(struct file *filp,
72 const char __user *user_buf, size_t count,
73 loff_t *ppos)
74 {
75 struct rproc *rproc = filp->private_data;
76 int ret, err = 0;
77 char buf[20];
78
79 if (count < 1 || count > sizeof(buf))
80 return -EINVAL;
81
82 ret = copy_from_user(buf, user_buf, count);
83 if (ret)
84 return -EFAULT;
85
86 /* remove end of line */
87 if (buf[count - 1] == '\n')
88 buf[count - 1] = '\0';
89
90 if (rproc->state == RPROC_CRASHED) {
91 dev_err(&rproc->dev, "can't change coredump configuration\n");
92 err = -EBUSY;
93 goto out;
94 }
95
96 if (!strncmp(buf, "disabled", count)) {
97 rproc->dump_conf = RPROC_COREDUMP_DISABLED;
98 } else if (!strncmp(buf, "enabled", count)) {
99 rproc->dump_conf = RPROC_COREDUMP_ENABLED;
100 } else if (!strncmp(buf, "inline", count)) {
101 rproc->dump_conf = RPROC_COREDUMP_INLINE;
102 } else {
103 dev_err(&rproc->dev, "Invalid coredump configuration\n");
104 err = -EINVAL;
105 }
106 out:
107 return err ? err : count;
108 }
109
110 static const struct file_operations rproc_coredump_fops = {
111 .read = rproc_coredump_read,
112 .write = rproc_coredump_write,
113 .open = simple_open,
114 .llseek = generic_file_llseek,
115 };
116
117 /*
118 * Some remote processors may support dumping trace logs into a shared
119 * memory buffer. We expose this trace buffer using debugfs, so users
120 * can easily tell what's going on remotely.
121 *
122 * We will most probably improve the rproc tracing facilities later on,
123 * but this kind of lightweight and simple mechanism is always good to have,
124 * as it provides very early tracing with little to no dependencies at all.
125 */
rproc_trace_read(struct file * filp,char __user * userbuf,size_t count,loff_t * ppos)126 static ssize_t rproc_trace_read(struct file *filp, char __user *userbuf,
127 size_t count, loff_t *ppos)
128 {
129 struct rproc_debug_trace *data = filp->private_data;
130 struct rproc_mem_entry *trace = &data->trace_mem;
131 void *va;
132 char buf[100];
133 int len;
134
135 va = rproc_da_to_va(data->rproc, trace->da, trace->len, NULL);
136
137 if (!va) {
138 len = scnprintf(buf, sizeof(buf), "Trace %s not available\n",
139 trace->name);
140 va = buf;
141 } else {
142 len = strnlen(va, trace->len);
143 }
144
145 return simple_read_from_buffer(userbuf, count, ppos, va, len);
146 }
147
148 static const struct file_operations trace_rproc_ops = {
149 .read = rproc_trace_read,
150 .open = simple_open,
151 .llseek = generic_file_llseek,
152 };
153
154 /* expose the name of the remote processor via debugfs */
rproc_name_read(struct file * filp,char __user * userbuf,size_t count,loff_t * ppos)155 static ssize_t rproc_name_read(struct file *filp, char __user *userbuf,
156 size_t count, loff_t *ppos)
157 {
158 struct rproc *rproc = filp->private_data;
159 /* need room for the name, a newline and a terminating null */
160 char buf[100];
161 int i;
162
163 i = scnprintf(buf, sizeof(buf), "%.98s\n", rproc->name);
164
165 return simple_read_from_buffer(userbuf, count, ppos, buf, i);
166 }
167
168 static const struct file_operations rproc_name_ops = {
169 .read = rproc_name_read,
170 .open = simple_open,
171 .llseek = generic_file_llseek,
172 };
173
174 /* expose recovery flag via debugfs */
rproc_recovery_read(struct file * filp,char __user * userbuf,size_t count,loff_t * ppos)175 static ssize_t rproc_recovery_read(struct file *filp, char __user *userbuf,
176 size_t count, loff_t *ppos)
177 {
178 struct rproc *rproc = filp->private_data;
179 char *buf = rproc->recovery_disabled ? "disabled\n" : "enabled\n";
180
181 return simple_read_from_buffer(userbuf, count, ppos, buf, strlen(buf));
182 }
183
184 /*
185 * By writing to the 'recovery' debugfs entry, we control the behavior of the
186 * recovery mechanism dynamically. The default value of this entry is "enabled".
187 *
188 * The 'recovery' debugfs entry supports these commands:
189 *
190 * enabled: When enabled, the remote processor will be automatically
191 * recovered whenever it crashes. Moreover, if the remote
192 * processor crashes while recovery is disabled, it will
193 * be automatically recovered too as soon as recovery is enabled.
194 *
195 * disabled: When disabled, a remote processor will remain in a crashed
196 * state if it crashes. This is useful for debugging purposes;
197 * without it, debugging a crash is substantially harder.
198 *
199 * recover: This function will trigger an immediate recovery if the
200 * remote processor is in a crashed state, without changing
201 * or checking the recovery state (enabled/disabled).
202 * This is useful during debugging sessions, when one expects
203 * additional crashes to happen after enabling recovery. In this
204 * case, enabling recovery will make it hard to debug subsequent
205 * crashes, so it's recommended to keep recovery disabled, and
206 * instead use the "recover" command as needed.
207 */
208 static ssize_t
rproc_recovery_write(struct file * filp,const char __user * user_buf,size_t count,loff_t * ppos)209 rproc_recovery_write(struct file *filp, const char __user *user_buf,
210 size_t count, loff_t *ppos)
211 {
212 struct rproc *rproc = filp->private_data;
213 char buf[10];
214 int ret;
215
216 if (count < 1 || count > sizeof(buf))
217 return -EINVAL;
218
219 ret = copy_from_user(buf, user_buf, count);
220 if (ret)
221 return -EFAULT;
222
223 /* remove end of line */
224 if (buf[count - 1] == '\n')
225 buf[count - 1] = '\0';
226
227 if (!strncmp(buf, "enabled", count)) {
228 /* change the flag and begin the recovery process if needed */
229 rproc->recovery_disabled = false;
230 rproc_trigger_recovery(rproc);
231 } else if (!strncmp(buf, "disabled", count)) {
232 rproc->recovery_disabled = true;
233 } else if (!strncmp(buf, "recover", count)) {
234 /* begin the recovery process without changing the flag */
235 rproc_trigger_recovery(rproc);
236 } else {
237 return -EINVAL;
238 }
239
240 return count;
241 }
242
243 static const struct file_operations rproc_recovery_ops = {
244 .read = rproc_recovery_read,
245 .write = rproc_recovery_write,
246 .open = simple_open,
247 .llseek = generic_file_llseek,
248 };
249
250 /* expose the crash trigger via debugfs */
251 static ssize_t
rproc_crash_write(struct file * filp,const char __user * user_buf,size_t count,loff_t * ppos)252 rproc_crash_write(struct file *filp, const char __user *user_buf,
253 size_t count, loff_t *ppos)
254 {
255 struct rproc *rproc = filp->private_data;
256 unsigned int type;
257 int ret;
258
259 ret = kstrtouint_from_user(user_buf, count, 0, &type);
260 if (ret < 0)
261 return ret;
262
263 rproc_report_crash(rproc, type);
264
265 return count;
266 }
267
268 static const struct file_operations rproc_crash_ops = {
269 .write = rproc_crash_write,
270 .open = simple_open,
271 .llseek = generic_file_llseek,
272 };
273
274 /* Expose resource table content via debugfs */
rproc_rsc_table_show(struct seq_file * seq,void * p)275 static int rproc_rsc_table_show(struct seq_file *seq, void *p)
276 {
277 static const char * const types[] = {"carveout", "devmem", "trace", "vdev"};
278 struct rproc *rproc = seq->private;
279 struct resource_table *table = rproc->table_ptr;
280 struct fw_rsc_carveout *c;
281 struct fw_rsc_devmem *d;
282 struct fw_rsc_trace *t;
283 struct fw_rsc_vdev *v;
284 int i, j;
285
286 if (!table) {
287 seq_puts(seq, "No resource table found\n");
288 return 0;
289 }
290
291 for (i = 0; i < table->num; i++) {
292 int offset = table->offset[i];
293 struct fw_rsc_hdr *hdr = (void *)table + offset;
294 void *rsc = (void *)hdr + sizeof(*hdr);
295
296 switch (hdr->type) {
297 case RSC_CARVEOUT:
298 c = rsc;
299 seq_printf(seq, "Entry %d is of type %s\n", i, types[hdr->type]);
300 seq_printf(seq, " Device Address 0x%x\n", c->da);
301 seq_printf(seq, " Physical Address 0x%x\n", c->pa);
302 seq_printf(seq, " Length 0x%x Bytes\n", c->len);
303 seq_printf(seq, " Flags 0x%x\n", c->flags);
304 seq_printf(seq, " Reserved (should be zero) [%d]\n", c->reserved);
305 seq_printf(seq, " Name %s\n\n", c->name);
306 break;
307 case RSC_DEVMEM:
308 d = rsc;
309 seq_printf(seq, "Entry %d is of type %s\n", i, types[hdr->type]);
310 seq_printf(seq, " Device Address 0x%x\n", d->da);
311 seq_printf(seq, " Physical Address 0x%x\n", d->pa);
312 seq_printf(seq, " Length 0x%x Bytes\n", d->len);
313 seq_printf(seq, " Flags 0x%x\n", d->flags);
314 seq_printf(seq, " Reserved (should be zero) [%d]\n", d->reserved);
315 seq_printf(seq, " Name %s\n\n", d->name);
316 break;
317 case RSC_TRACE:
318 t = rsc;
319 seq_printf(seq, "Entry %d is of type %s\n", i, types[hdr->type]);
320 seq_printf(seq, " Device Address 0x%x\n", t->da);
321 seq_printf(seq, " Length 0x%x Bytes\n", t->len);
322 seq_printf(seq, " Reserved (should be zero) [%d]\n", t->reserved);
323 seq_printf(seq, " Name %s\n\n", t->name);
324 break;
325 case RSC_VDEV:
326 v = rsc;
327 seq_printf(seq, "Entry %d is of type %s\n", i, types[hdr->type]);
328
329 seq_printf(seq, " ID %d\n", v->id);
330 seq_printf(seq, " Notify ID %d\n", v->notifyid);
331 seq_printf(seq, " Device features 0x%x\n", v->dfeatures);
332 seq_printf(seq, " Guest features 0x%x\n", v->gfeatures);
333 seq_printf(seq, " Config length 0x%x\n", v->config_len);
334 seq_printf(seq, " Status 0x%x\n", v->status);
335 seq_printf(seq, " Number of vrings %d\n", v->num_of_vrings);
336 seq_printf(seq, " Reserved (should be zero) [%d][%d]\n\n",
337 v->reserved[0], v->reserved[1]);
338
339 for (j = 0; j < v->num_of_vrings; j++) {
340 seq_printf(seq, " Vring %d\n", j);
341 seq_printf(seq, " Device Address 0x%x\n", v->vring[j].da);
342 seq_printf(seq, " Alignment %d\n", v->vring[j].align);
343 seq_printf(seq, " Number of buffers %d\n", v->vring[j].num);
344 seq_printf(seq, " Notify ID %d\n", v->vring[j].notifyid);
345 seq_printf(seq, " Physical Address 0x%x\n\n",
346 v->vring[j].pa);
347 }
348 break;
349 default:
350 seq_printf(seq, "Unknown resource type found: %d [hdr: %pK]\n",
351 hdr->type, hdr);
352 break;
353 }
354 }
355
356 return 0;
357 }
358
359 DEFINE_SHOW_ATTRIBUTE(rproc_rsc_table);
360
361 /* Expose carveout content via debugfs */
rproc_carveouts_show(struct seq_file * seq,void * p)362 static int rproc_carveouts_show(struct seq_file *seq, void *p)
363 {
364 struct rproc *rproc = seq->private;
365 struct rproc_mem_entry *carveout;
366
367 list_for_each_entry(carveout, &rproc->carveouts, node) {
368 seq_puts(seq, "Carveout memory entry:\n");
369 seq_printf(seq, "\tName: %s\n", carveout->name);
370 seq_printf(seq, "\tVirtual address: %pK\n", carveout->va);
371 seq_printf(seq, "\tDMA address: %pad\n", &carveout->dma);
372 seq_printf(seq, "\tDevice address: 0x%x\n", carveout->da);
373 seq_printf(seq, "\tLength: 0x%zx Bytes\n\n", carveout->len);
374 }
375
376 return 0;
377 }
378
379 DEFINE_SHOW_ATTRIBUTE(rproc_carveouts);
380
rproc_remove_trace_file(struct dentry * tfile)381 void rproc_remove_trace_file(struct dentry *tfile)
382 {
383 debugfs_remove(tfile);
384 }
385
rproc_create_trace_file(const char * name,struct rproc * rproc,struct rproc_debug_trace * trace)386 struct dentry *rproc_create_trace_file(const char *name, struct rproc *rproc,
387 struct rproc_debug_trace *trace)
388 {
389 return debugfs_create_file(name, 0400, rproc->dbg_dir, trace,
390 &trace_rproc_ops);
391 }
392
rproc_delete_debug_dir(struct rproc * rproc)393 void rproc_delete_debug_dir(struct rproc *rproc)
394 {
395 debugfs_remove_recursive(rproc->dbg_dir);
396 }
397
rproc_create_debug_dir(struct rproc * rproc)398 void rproc_create_debug_dir(struct rproc *rproc)
399 {
400 struct device *dev = &rproc->dev;
401
402 if (!rproc_dbg)
403 return;
404
405 rproc->dbg_dir = debugfs_create_dir(dev_name(dev), rproc_dbg);
406
407 debugfs_create_file("name", 0400, rproc->dbg_dir,
408 rproc, &rproc_name_ops);
409 debugfs_create_file("recovery", 0600, rproc->dbg_dir,
410 rproc, &rproc_recovery_ops);
411 debugfs_create_file("crash", 0200, rproc->dbg_dir,
412 rproc, &rproc_crash_ops);
413 debugfs_create_file("resource_table", 0400, rproc->dbg_dir,
414 rproc, &rproc_rsc_table_fops);
415 debugfs_create_file("carveout_memories", 0400, rproc->dbg_dir,
416 rproc, &rproc_carveouts_fops);
417 debugfs_create_file("coredump", 0600, rproc->dbg_dir,
418 rproc, &rproc_coredump_fops);
419 }
420
rproc_init_debugfs(void)421 void __init rproc_init_debugfs(void)
422 {
423 if (debugfs_initialized())
424 rproc_dbg = debugfs_create_dir(KBUILD_MODNAME, NULL);
425 }
426
rproc_exit_debugfs(void)427 void __exit rproc_exit_debugfs(void)
428 {
429 debugfs_remove(rproc_dbg);
430 }
431