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