root/drivers/remoteproc/remoteproc_debugfs.c

DEFINITIONS

1. rproc_trace_read
2. rproc_name_read
3. rproc_recovery_read
4. rproc_recovery_write
5. rproc_crash_write
6. rproc_rsc_table_show
7. rproc_rsc_table_open
8. rproc_carveouts_show
9. rproc_carveouts_open
10. rproc_remove_trace_file
11. rproc_create_trace_file
12. rproc_delete_debug_dir
13. rproc_create_debug_dir
14. rproc_init_debugfs
15. rproc_exit_debugfs

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