drivers/staging/android/fiq_debugger/fiq_debugger.c

   1 /*
   2  * drivers/staging/android/fiq_debugger.c
   3  *
   4  * Serial Debugger Interface accessed through an FIQ interrupt.
   5  *
   6  * Copyright (C) 2008 Google, Inc.
   7  *
   8  * This software is licensed under the terms of the GNU General Public
   9  * License version 2, as published by the Free Software Foundation, and
  10  * may be copied, distributed, and modified under those terms.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  */
  17
  18 #include <stdarg.h>
  19 #include <linux/module.h>
  20 #include <linux/io.h>
  21 #include <linux/console.h>
  22 #include <linux/interrupt.h>
  23 #include <linux/clk.h>
  24 #include <linux/platform_device.h>
  25 #include <linux/kernel_stat.h>
  26 #include <linux/kmsg_dump.h>
  27 #include <linux/irq.h>
  28 #include <linux/delay.h>
  29 #include <linux/reboot.h>
  30 #include <linux/sched.h>
  31 #include <linux/slab.h>
  32 #include <linux/smp.h>
  33 #include <linux/timer.h>
  34 #include <linux/tty.h>
  35 #include <linux/tty_flip.h>
  36 #include <linux/wakelock.h>
  37
  38 #ifdef CONFIG_FIQ_GLUE
  39 #include <asm/fiq_glue.h>
  40 #endif
  41
  42 #ifdef CONFIG_FIQ_DEBUGGER_UART_OVERLAY
  43 #include <linux/of.h>
  44 #endif
  45
  46 #include <linux/uaccess.h>
  47
  48 #include "fiq_debugger.h"
  49 #include "fiq_debugger_priv.h"
  50 #include "fiq_debugger_ringbuf.h"
  51
  52 #define DEBUG_MAX 64
  53 #define MAX_UNHANDLED_FIQ_COUNT 1000000
  54
  55 #define MAX_FIQ_DEBUGGER_PORTS 4
  56
  57 struct fiq_debugger_state {
  58 #ifdef CONFIG_FIQ_GLUE
  59         struct fiq_glue_handler handler;
  60 #endif
  61         struct fiq_debugger_output output;
  62
  63         int fiq;
  64         int uart_irq;
  65         int signal_irq;
  66         int wakeup_irq;
  67         bool wakeup_irq_no_set_wake;
  68         struct clk *clk;
  69         struct fiq_debugger_pdata *pdata;
  70         struct platform_device *pdev;
  71
  72         char debug_cmd[DEBUG_MAX];
  73         int debug_busy;
  74         int debug_abort;
  75
  76         char debug_buf[DEBUG_MAX];
  77         int debug_count;
  78
  79         bool no_sleep;
  80         bool debug_enable;
  81         bool ignore_next_wakeup_irq;
  82         struct timer_list sleep_timer;
  83         spinlock_t sleep_timer_lock;
  84         bool uart_enabled;
  85         struct wake_lock debugger_wake_lock;
  86         bool console_enable;
  87         int current_cpu;
  88         atomic_t unhandled_fiq_count;
  89         bool in_fiq;
  90
  91         struct work_struct work;
  92         spinlock_t work_lock;
  93         char work_cmd[DEBUG_MAX];
  94
  95 #ifdef CONFIG_FIQ_DEBUGGER_CONSOLE
  96         spinlock_t console_lock;
  97         struct console console;
  98         struct tty_port tty_port;
  99         struct fiq_debugger_ringbuf *tty_rbuf;
 100         bool syslog_dumping;
 101 #endif
 102
 103         unsigned int last_irqs[NR_IRQS];
 104         unsigned int last_local_timer_irqs[NR_CPUS];
 105 };
 106
 107 #ifdef CONFIG_FIQ_DEBUGGER_CONSOLE
 108 struct tty_driver *fiq_tty_driver;
 109 #endif
 110
 111 #ifdef CONFIG_FIQ_DEBUGGER_NO_SLEEP
 112 static bool initial_no_sleep = true;
 113 #else
 114 static bool initial_no_sleep;
 115 #endif
 116
 117 #ifdef CONFIG_FIQ_DEBUGGER_CONSOLE_DEFAULT_ENABLE
 118 static bool initial_debug_enable = true;
 119 static bool initial_console_enable = true;
 120 #else
 121 static bool initial_debug_enable;
 122 static bool initial_console_enable;
 123 #endif
 124
 125 static bool fiq_kgdb_enable;
 126 static bool fiq_debugger_disable;
 127
 128 module_param_named(no_sleep, initial_no_sleep, bool, 0644);
 129 module_param_named(debug_enable, initial_debug_enable, bool, 0644);
 130 module_param_named(console_enable, initial_console_enable, bool, 0644);
 131 module_param_named(kgdb_enable, fiq_kgdb_enable, bool, 0644);
 132 module_param_named(disable, fiq_debugger_disable, bool, 0644);
 133
 134 #ifdef CONFIG_FIQ_DEBUGGER_WAKEUP_IRQ_ALWAYS_ON
 135 static inline
 136 void fiq_debugger_enable_wakeup_irq(struct fiq_debugger_state *state) {}
 137 static inline
 138 void fiq_debugger_disable_wakeup_irq(struct fiq_debugger_state *state) {}
 139 #else
 140 static inline
 141 void fiq_debugger_enable_wakeup_irq(struct fiq_debugger_state *state)
 142 {
 143         if (state->wakeup_irq < 0)
 144                 return;
 145         enable_irq(state->wakeup_irq);
 146         if (!state->wakeup_irq_no_set_wake)
 147                 enable_irq_wake(state->wakeup_irq);
 148 }
 149 static inline
 150 void fiq_debugger_disable_wakeup_irq(struct fiq_debugger_state *state)
 151 {
 152         if (state->wakeup_irq < 0)
 153                 return;
 154         disable_irq_nosync(state->wakeup_irq);
 155         if (!state->wakeup_irq_no_set_wake)
 156                 disable_irq_wake(state->wakeup_irq);
 157 }
 158 #endif
 159
 160 static inline bool fiq_debugger_have_fiq(struct fiq_debugger_state *state)
 161 {
 162         return (state->fiq >= 0);
 163 }
 164
 165 #ifdef CONFIG_FIQ_GLUE
 166 static void fiq_debugger_force_irq(struct fiq_debugger_state *state)
 167 {
 168         unsigned int irq = state->signal_irq;
 169
 170         if (WARN_ON(!fiq_debugger_have_fiq(state)))
 171                 return;
 172         if (state->pdata->force_irq) {
 173                 state->pdata->force_irq(state->pdev, irq);
 174         } else {
 175                 struct irq_chip *chip = irq_get_chip(irq);
 176                 if (chip && chip->irq_retrigger)
 177                         chip->irq_retrigger(irq_get_irq_data(irq));
 178         }
 179 }
 180 #endif
 181
 182 static void fiq_debugger_uart_enable(struct fiq_debugger_state *state)
 183 {
 184         if (state->clk)
 185                 clk_enable(state->clk);
 186         if (state->pdata->uart_enable)
 187                 state->pdata->uart_enable(state->pdev);
 188 }
 189
 190 static void fiq_debugger_uart_disable(struct fiq_debugger_state *state)
 191 {
 192         if (state->pdata->uart_disable)
 193                 state->pdata->uart_disable(state->pdev);
 194         if (state->clk)
 195                 clk_disable(state->clk);
 196 }
 197
 198 static void fiq_debugger_uart_flush(struct fiq_debugger_state *state)
 199 {
 200         if (state->pdata->uart_flush)
 201                 state->pdata->uart_flush(state->pdev);
 202 }
 203
 204 static void fiq_debugger_putc(struct fiq_debugger_state *state, char c)
 205 {
 206         state->pdata->uart_putc(state->pdev, c);
 207 }
 208
 209 static void fiq_debugger_puts(struct fiq_debugger_state *state, char *s)
 210 {
 211         unsigned c;
 212         while ((c = *s++)) {
 213                 if (c == '\n')
 214                         fiq_debugger_putc(state, '\r');
 215                 fiq_debugger_putc(state, c);
 216         }
 217 }
 218
 219 static void fiq_debugger_prompt(struct fiq_debugger_state *state)
 220 {
 221         fiq_debugger_puts(state, "debug> ");
 222 }
 223
 224 static void fiq_debugger_dump_kernel_log(struct fiq_debugger_state *state)
 225 {
 226         char buf[512];
 227         size_t len;
 228         struct kmsg_dumper dumper = { .active = true };
 229
 230
 231         kmsg_dump_rewind_nolock(&dumper);
 232         while (kmsg_dump_get_line_nolock(&dumper, true, buf,
 233                                          sizeof(buf) - 1, &len)) {
 234                 buf[len] = 0;
 235                 fiq_debugger_puts(state, buf);
 236         }
 237 }
 238
 239 static void fiq_debugger_printf(struct fiq_debugger_output *output,
 240                                const char *fmt, ...)
 241 {
 242         struct fiq_debugger_state *state;
 243         char buf[256];
 244         va_list ap;
 245
 246         state = container_of(output, struct fiq_debugger_state, output);
 247         va_start(ap, fmt);
 248         vsnprintf(buf, sizeof(buf), fmt, ap);
 249         va_end(ap);
 250
 251         fiq_debugger_puts(state, buf);
 252 }
 253
 254 /* Safe outside fiq context */
 255 static int fiq_debugger_printf_nfiq(void *cookie, const char *fmt, ...)
 256 {
 257         struct fiq_debugger_state *state = cookie;
 258         char buf[256];
 259         va_list ap;
 260         unsigned long irq_flags;
 261
 262         va_start(ap, fmt);
 263         vsnprintf(buf, 128, fmt, ap);
 264         va_end(ap);
 265
 266         local_irq_save(irq_flags);
 267         fiq_debugger_puts(state, buf);
 268         fiq_debugger_uart_flush(state);
 269         local_irq_restore(irq_flags);
 270         return state->debug_abort;
 271 }
 272
 273 static void fiq_debugger_dump_irqs(struct fiq_debugger_state *state)
 274 {
 275         int n;
 276         struct irq_desc *desc;
 277
 278         fiq_debugger_printf(&state->output,
 279                         "irqnr       total  since-last   status  name\n");
 280         for_each_irq_desc(n, desc) {
 281                 struct irqaction *act = desc->action;
 282                 if (!act && !kstat_irqs(n))
 283                         continue;
 284                 fiq_debugger_printf(&state->output, "%5d: %10u %11u %8x  %s\n", n,
 285                         kstat_irqs(n),
 286                         kstat_irqs(n) - state->last_irqs[n],
 287                         desc->status_use_accessors,
 288                         (act && act->name) ? act->name : "???");
 289                 state->last_irqs[n] = kstat_irqs(n);
 290         }
 291 }
 292
 293 static void fiq_debugger_do_ps(struct fiq_debugger_state *state)
 294 {
 295         struct task_struct *g;
 296         struct task_struct *p;
 297         unsigned task_state;
 298         static const char stat_nam[] = "RSDTtZX";
 299
 300         fiq_debugger_printf(&state->output, "pid   ppid  prio task            pc\n");
 301         read_lock(&tasklist_lock);
 302         do_each_thread(g, p) {
 303                 task_state = p->state ? __ffs(p->state) + 1 : 0;
 304                 fiq_debugger_printf(&state->output,
 305                              "%5d %5d %4d ", p->pid, p->parent->pid, p->prio);
 306                 fiq_debugger_printf(&state->output, "%-13.13s %c", p->comm,
 307                              task_state >= sizeof(stat_nam) ? '?' : stat_nam[task_state]);
 308                 if (task_state == TASK_RUNNING)
 309                         fiq_debugger_printf(&state->output, " running\n");
 310                 else
 311                         fiq_debugger_printf(&state->output, " %08lx\n",
 312                                         thread_saved_pc(p));
 313         } while_each_thread(g, p);
 314         read_unlock(&tasklist_lock);
 315 }
 316
 317 #ifdef CONFIG_FIQ_DEBUGGER_CONSOLE
 318 static void fiq_debugger_begin_syslog_dump(struct fiq_debugger_state *state)
 319 {
 320         state->syslog_dumping = true;
 321 }
 322
 323 static void fiq_debugger_end_syslog_dump(struct fiq_debugger_state *state)
 324 {
 325         state->syslog_dumping = false;
 326 }
 327 #else
 328 extern int do_syslog(int type, char __user *bug, int count);
 329 static void fiq_debugger_begin_syslog_dump(struct fiq_debugger_state *state)
 330 {
 331         do_syslog(5 /* clear */, NULL, 0);
 332 }
 333
 334 static void fiq_debugger_end_syslog_dump(struct fiq_debugger_state *state)
 335 {
 336         fiq_debugger_dump_kernel_log(state);
 337 }
 338 #endif
 339
 340 static void fiq_debugger_do_sysrq(struct fiq_debugger_state *state, char rq)
 341 {
 342         if ((rq == 'g' || rq == 'G') && !fiq_kgdb_enable) {
 343                 fiq_debugger_printf(&state->output, "sysrq-g blocked\n");
 344                 return;
 345         }
 346         fiq_debugger_begin_syslog_dump(state);
 347         handle_sysrq(rq);
 348         fiq_debugger_end_syslog_dump(state);
 349 }
 350
 351 #ifdef CONFIG_KGDB
 352 static void fiq_debugger_do_kgdb(struct fiq_debugger_state *state)
 353 {
 354         if (!fiq_kgdb_enable) {
 355                 fiq_debugger_printf(&state->output, "kgdb through fiq debugger not enabled\n");
 356                 return;
 357         }
 358
 359         fiq_debugger_printf(&state->output, "enabling console and triggering kgdb\n");
 360         state->console_enable = true;
 361         handle_sysrq('g');
 362 }
 363 #endif
 364
 365 static void fiq_debugger_schedule_work(struct fiq_debugger_state *state,
 366                 char *cmd)
 367 {
 368         unsigned long flags;
 369
 370         spin_lock_irqsave(&state->work_lock, flags);
 371         if (state->work_cmd[0] != '\0') {
 372                 fiq_debugger_printf(&state->output, "work command processor busy\n");
 373                 spin_unlock_irqrestore(&state->work_lock, flags);
 374                 return;
 375         }
 376
 377         strlcpy(state->work_cmd, cmd, sizeof(state->work_cmd));
 378         spin_unlock_irqrestore(&state->work_lock, flags);
 379
 380         schedule_work(&state->work);
 381 }
 382
 383 static void fiq_debugger_work(struct work_struct *work)
 384 {
 385         struct fiq_debugger_state *state;
 386         char work_cmd[DEBUG_MAX];
 387         char *cmd;
 388         unsigned long flags;
 389
 390         state = container_of(work, struct fiq_debugger_state, work);
 391
 392         spin_lock_irqsave(&state->work_lock, flags);
 393
 394         strlcpy(work_cmd, state->work_cmd, sizeof(work_cmd));
 395         state->work_cmd[0] = '\0';
 396
 397         spin_unlock_irqrestore(&state->work_lock, flags);
 398
 399         cmd = work_cmd;
 400         if (!strncmp(cmd, "reboot", 6)) {
 401                 cmd += 6;
 402                 while (*cmd == ' ')
 403                         cmd++;
 404                 if (cmd != '\0')
 405                         kernel_restart(cmd);
 406                 else
 407                         kernel_restart(NULL);
 408         } else {
 409                 fiq_debugger_printf(&state->output, "unknown work command '%s'\n",
 410                                 work_cmd);
 411         }
 412 }
 413
 414 /* This function CANNOT be called in FIQ context */
 415 static void fiq_debugger_irq_exec(struct fiq_debugger_state *state, char *cmd)
 416 {
 417         if (!strcmp(cmd, "ps"))
 418                 fiq_debugger_do_ps(state);
 419         if (!strcmp(cmd, "sysrq"))
 420                 fiq_debugger_do_sysrq(state, 'h');
 421         if (!strncmp(cmd, "sysrq ", 6))
 422                 fiq_debugger_do_sysrq(state, cmd[6]);
 423 #ifdef CONFIG_KGDB
 424         if (!strcmp(cmd, "kgdb"))
 425                 fiq_debugger_do_kgdb(state);
 426 #endif
 427         if (!strncmp(cmd, "reboot", 6))
 428                 fiq_debugger_schedule_work(state, cmd);
 429 }
 430
 431 static void fiq_debugger_help(struct fiq_debugger_state *state)
 432 {
 433         fiq_debugger_printf(&state->output,
 434                                 "FIQ Debugger commands:\n"
 435                                 " pc            PC status\n"
 436                                 " regs          Register dump\n"
 437                                 " allregs       Extended Register dump\n"
 438                                 " bt            Stack trace\n"
 439                                 " reboot [<c>]  Reboot with command <c>\n"
 440                                 " reset [<c>]   Hard reset with command <c>\n"
 441                                 " irqs          Interupt status\n"
 442                                 " kmsg          Kernel log\n"
 443                                 " version       Kernel version\n");
 444         fiq_debugger_printf(&state->output,
 445                                 " sleep         Allow sleep while in FIQ\n"
 446                                 " nosleep       Disable sleep while in FIQ\n"
 447                                 " console       Switch terminal to console\n"
 448                                 " cpu           Current CPU\n"
 449                                 " cpu <number>  Switch to CPU<number>\n");
 450         fiq_debugger_printf(&state->output,
 451                                 " ps            Process list\n"
 452                                 " sysrq         sysrq options\n"
 453                                 " sysrq <param> Execute sysrq with <param>\n");
 454 #ifdef CONFIG_KGDB
 455         fiq_debugger_printf(&state->output,
 456                                 " kgdb          Enter kernel debugger\n");
 457 #endif
 458 }
 459
 460 static void fiq_debugger_take_affinity(void *info)
 461 {
 462         struct fiq_debugger_state *state = info;
 463         struct cpumask cpumask;
 464
 465         cpumask_clear(&cpumask);
 466         cpumask_set_cpu(get_cpu(), &cpumask);
 467
 468         irq_set_affinity(state->uart_irq, &cpumask);
 469 }
 470
 471 static void fiq_debugger_switch_cpu(struct fiq_debugger_state *state, int cpu)
 472 {
 473         if (!fiq_debugger_have_fiq(state))
 474                 smp_call_function_single(cpu, fiq_debugger_take_affinity, state,
 475                                 false);
 476         state->current_cpu = cpu;
 477 }
 478
 479 static bool fiq_debugger_fiq_exec(struct fiq_debugger_state *state,
 480                         const char *cmd, const struct pt_regs *regs,
 481                         void *svc_sp)
 482 {
 483         bool signal_helper = false;
 484
 485         if (!strcmp(cmd, "help") || !strcmp(cmd, "?")) {
 486                 fiq_debugger_help(state);
 487         } else if (!strcmp(cmd, "pc")) {
 488                 fiq_debugger_dump_pc(&state->output, regs);
 489         } else if (!strcmp(cmd, "regs")) {
 490                 fiq_debugger_dump_regs(&state->output, regs);
 491         } else if (!strcmp(cmd, "allregs")) {
 492                 fiq_debugger_dump_allregs(&state->output, regs);
 493         } else if (!strcmp(cmd, "bt")) {
 494                 fiq_debugger_dump_stacktrace(&state->output, regs, 100, svc_sp);
 495         } else if (!strncmp(cmd, "reset", 5)) {
 496                 cmd += 5;
 497                 while (*cmd == ' ')
 498                         cmd++;
 499                 if (*cmd) {
 500                         char tmp_cmd[32];
 501                         strlcpy(tmp_cmd, cmd, sizeof(tmp_cmd));
 502                         blocking_notifier_call_chain(&reboot_notifier_list,
 503                                                 SYS_RESTART, (char *)cmd);
 504                         machine_restart(tmp_cmd);
 505                 } else {
 506                         machine_restart(NULL);
 507                 }
 508         } else if (!strcmp(cmd, "irqs")) {
 509                 fiq_debugger_dump_irqs(state);
 510         } else if (!strcmp(cmd, "kmsg")) {
 511                 fiq_debugger_dump_kernel_log(state);
 512         } else if (!strcmp(cmd, "version")) {
 513                 fiq_debugger_printf(&state->output, "%s\n", linux_banner);
 514         } else if (!strcmp(cmd, "sleep")) {
 515                 state->no_sleep = false;
 516                 fiq_debugger_printf(&state->output, "enabling sleep\n");
 517         } else if (!strcmp(cmd, "nosleep")) {
 518                 state->no_sleep = true;
 519                 fiq_debugger_printf(&state->output, "disabling sleep\n");
 520         } else if (!strcmp(cmd, "console")) {
 521                 fiq_debugger_printf(&state->output, "console mode\n");
 522                 fiq_debugger_uart_flush(state);
 523                 state->console_enable = true;
 524         } else if (!strcmp(cmd, "cpu")) {
 525                 fiq_debugger_printf(&state->output, "cpu %d\n", state->current_cpu);
 526         } else if (!strncmp(cmd, "cpu ", 4)) {
 527                 unsigned long cpu = 0;
 528                 if (kstrtoul(cmd + 4, 10, &cpu) == 0)
 529                         fiq_debugger_switch_cpu(state, cpu);
 530                 else
 531                         fiq_debugger_printf(&state->output, "invalid cpu\n");
 532                 fiq_debugger_printf(&state->output, "cpu %d\n", state->current_cpu);
 533         } else {
 534                 if (state->debug_busy) {
 535                         fiq_debugger_printf(&state->output,
 536                                 "command processor busy. trying to abort.\n");
 537                         state->debug_abort = -1;
 538                 } else {
 539                         strcpy(state->debug_cmd, cmd);
 540                         state->debug_busy = 1;
 541                 }
 542
 543                 return true;
 544         }
 545         if (!state->console_enable)
 546                 fiq_debugger_prompt(state);
 547
 548         return signal_helper;
 549 }
 550
 551 static void fiq_debugger_sleep_timer_expired(unsigned long data)
 552 {
 553         struct fiq_debugger_state *state = (struct fiq_debugger_state *)data;
 554         unsigned long flags;
 555
 556         spin_lock_irqsave(&state->sleep_timer_lock, flags);
 557         if (state->uart_enabled && !state->no_sleep) {
 558                 if (state->debug_enable && !state->console_enable) {
 559                         state->debug_enable = false;
 560                         fiq_debugger_printf_nfiq(state,
 561                                         "suspending fiq debugger\n");
 562                 }
 563                 state->ignore_next_wakeup_irq = true;
 564                 fiq_debugger_uart_disable(state);
 565                 state->uart_enabled = false;
 566                 fiq_debugger_enable_wakeup_irq(state);
 567         }
 568         wake_unlock(&state->debugger_wake_lock);
 569         spin_unlock_irqrestore(&state->sleep_timer_lock, flags);
 570 }
 571
 572 static void fiq_debugger_handle_wakeup(struct fiq_debugger_state *state)
 573 {
 574         unsigned long flags;
 575
 576         spin_lock_irqsave(&state->sleep_timer_lock, flags);
 577         if (state->wakeup_irq >= 0 && state->ignore_next_wakeup_irq) {
 578                 state->ignore_next_wakeup_irq = false;
 579         } else if (!state->uart_enabled) {
 580                 wake_lock(&state->debugger_wake_lock);
 581                 fiq_debugger_uart_enable(state);
 582                 state->uart_enabled = true;
 583                 fiq_debugger_disable_wakeup_irq(state);
 584                 mod_timer(&state->sleep_timer, jiffies + HZ / 2);
 585         }
 586         spin_unlock_irqrestore(&state->sleep_timer_lock, flags);
 587 }
 588
 589 static irqreturn_t fiq_debugger_wakeup_irq_handler(int irq, void *dev)
 590 {
 591         struct fiq_debugger_state *state = dev;
 592
 593         if (!state->no_sleep)
 594                 fiq_debugger_puts(state, "WAKEUP\n");
 595         fiq_debugger_handle_wakeup(state);
 596
 597         return IRQ_HANDLED;
 598 }
 599
 600 static
 601 void fiq_debugger_handle_console_irq_context(struct fiq_debugger_state *state)
 602 {
 603 #if defined(CONFIG_FIQ_DEBUGGER_CONSOLE)
 604         if (state->tty_port.ops) {
 605                 int i;
 606                 int count = fiq_debugger_ringbuf_level(state->tty_rbuf);
 607                 for (i = 0; i < count; i++) {
 608                         int c = fiq_debugger_ringbuf_peek(state->tty_rbuf, 0);
 609                         tty_insert_flip_char(&state->tty_port, c, TTY_NORMAL);
 610                         if (!fiq_debugger_ringbuf_consume(state->tty_rbuf, 1))
 611                                 pr_warn("fiq tty failed to consume byte\n");
 612                 }
 613                 tty_flip_buffer_push(&state->tty_port);
 614         }
 615 #endif
 616 }
 617
 618 static void fiq_debugger_handle_irq_context(struct fiq_debugger_state *state)
 619 {
 620         if (!state->no_sleep) {
 621                 unsigned long flags;
 622
 623                 spin_lock_irqsave(&state->sleep_timer_lock, flags);
 624                 wake_lock(&state->debugger_wake_lock);
 625                 mod_timer(&state->sleep_timer, jiffies + HZ * 5);
 626                 spin_unlock_irqrestore(&state->sleep_timer_lock, flags);
 627         }
 628         fiq_debugger_handle_console_irq_context(state);
 629         if (state->debug_busy) {
 630                 fiq_debugger_irq_exec(state, state->debug_cmd);
 631                 if (!state->console_enable)
 632                         fiq_debugger_prompt(state);
 633                 state->debug_busy = 0;
 634         }
 635 }
 636
 637 static int fiq_debugger_getc(struct fiq_debugger_state *state)
 638 {
 639         return state->pdata->uart_getc(state->pdev);
 640 }
 641
 642 static bool fiq_debugger_handle_uart_interrupt(struct fiq_debugger_state *state,
 643                         int this_cpu, const struct pt_regs *regs, void *svc_sp)
 644 {
 645         int c;
 646         static int last_c;
 647         int count = 0;
 648         bool signal_helper = false;
 649
 650         if ((this_cpu != state->current_cpu) && (cpu_online(state->current_cpu))) {
 651                 if (state->in_fiq)
 652                         return false;
 653
 654                 if (atomic_inc_return(&state->unhandled_fiq_count) !=
 655                                         MAX_UNHANDLED_FIQ_COUNT)
 656                         return false;
 657
 658                 fiq_debugger_printf(&state->output,
 659                         "fiq_debugger: cpu %d not responding, "
 660                         "reverting to cpu %d\n", state->current_cpu,
 661                         this_cpu);
 662
 663                 atomic_set(&state->unhandled_fiq_count, 0);
 664                 fiq_debugger_switch_cpu(state, this_cpu);
 665                 return false;
 666         }
 667
 668         if (this_cpu != state->current_cpu)
 669                 state->current_cpu = this_cpu;
 670
 671         state->in_fiq = true;
 672
 673         while ((c = fiq_debugger_getc(state)) != FIQ_DEBUGGER_NO_CHAR) {
 674                 count++;
 675                 if (!state->debug_enable) {
 676                         if ((c == 13) || (c == 10)) {
 677                                 state->debug_enable = true;
 678                                 state->debug_count = 0;
 679                                 fiq_debugger_prompt(state);
 680                         }
 681                 } else if (c == FIQ_DEBUGGER_BREAK) {
 682                         state->console_enable = false;
 683                         fiq_debugger_puts(state, "fiq debugger mode\n");
 684                         state->debug_count = 0;
 685                         fiq_debugger_prompt(state);
 686 #ifdef CONFIG_FIQ_DEBUGGER_CONSOLE
 687                 } else if (state->console_enable && state->tty_rbuf) {
 688                         fiq_debugger_ringbuf_push(state->tty_rbuf, c);
 689                         signal_helper = true;
 690 #endif
 691                 } else if ((c >= ' ') && (c < 127)) {
 692                         if (state->debug_count < (DEBUG_MAX - 1)) {
 693                                 state->debug_buf[state->debug_count++] = c;
 694                                 fiq_debugger_putc(state, c);
 695                         }
 696                 } else if ((c == 8) || (c == 127)) {
 697                         if (state->debug_count > 0) {
 698                                 state->debug_count--;
 699                                 fiq_debugger_putc(state, 8);
 700                                 fiq_debugger_putc(state, ' ');
 701                                 fiq_debugger_putc(state, 8);
 702                         }
 703                 } else if ((c == 13) || (c == 10)) {
 704                         if (c == '\r' || (c == '\n' && last_c != '\r')) {
 705                                 fiq_debugger_putc(state, '\r');
 706                                 fiq_debugger_putc(state, '\n');
 707                         }
 708                         if (state->debug_count) {
 709                                 state->debug_buf[state->debug_count] = 0;
 710                                 state->debug_count = 0;
 711                                 signal_helper |=
 712                                         fiq_debugger_fiq_exec(state,
 713                                                         state->debug_buf,
 714                                                         regs, svc_sp);
 715                         } else {
 716                                 fiq_debugger_prompt(state);
 717                         }
 718                 }
 719                 last_c = c;
 720         }
 721         if (!state->console_enable)
 722                 fiq_debugger_uart_flush(state);
 723         if (state->pdata->fiq_ack)
 724                 state->pdata->fiq_ack(state->pdev, state->fiq);
 725
 726         /* poke sleep timer if necessary */
 727         if (state->debug_enable && !state->no_sleep)
 728                 signal_helper = true;
 729
 730         atomic_set(&state->unhandled_fiq_count, 0);
 731         state->in_fiq = false;
 732
 733         return signal_helper;
 734 }
 735
 736 #ifdef CONFIG_FIQ_GLUE
 737 static void fiq_debugger_fiq(struct fiq_glue_handler *h,
 738                 const struct pt_regs *regs, void *svc_sp)
 739 {
 740         struct fiq_debugger_state *state =
 741                 container_of(h, struct fiq_debugger_state, handler);
 742         unsigned int this_cpu = THREAD_INFO(svc_sp)->cpu;
 743         bool need_irq;
 744
 745         need_irq = fiq_debugger_handle_uart_interrupt(state, this_cpu, regs,
 746                         svc_sp);
 747         if (need_irq)
 748                 fiq_debugger_force_irq(state);
 749 }
 750 #endif
 751
 752 /*
 753  * When not using FIQs, we only use this single interrupt as an entry point.
 754  * This just effectively takes over the UART interrupt and does all the work
 755  * in this context.
 756  */
 757 static irqreturn_t fiq_debugger_uart_irq(int irq, void *dev)
 758 {
 759         struct fiq_debugger_state *state = dev;
 760         bool not_done;
 761
 762         fiq_debugger_handle_wakeup(state);
 763
 764         /* handle the debugger irq in regular context */
 765         not_done = fiq_debugger_handle_uart_interrupt(state, smp_processor_id(),
 766                                               get_irq_regs(),
 767                                               current_thread_info());
 768         if (not_done)
 769                 fiq_debugger_handle_irq_context(state);
 770
 771         return IRQ_HANDLED;
 772 }
 773
 774 /*
 775  * If FIQs are used, not everything can happen in fiq context.
 776  * FIQ handler does what it can and then signals this interrupt to finish the
 777  * job in irq context.
 778  */
 779 static irqreturn_t fiq_debugger_signal_irq(int irq, void *dev)
 780 {
 781         struct fiq_debugger_state *state = dev;
 782
 783         if (state->pdata->force_irq_ack)
 784                 state->pdata->force_irq_ack(state->pdev, state->signal_irq);
 785
 786         fiq_debugger_handle_irq_context(state);
 787
 788         return IRQ_HANDLED;
 789 }
 790
 791 #ifdef CONFIG_FIQ_GLUE
 792 static void fiq_debugger_resume(struct fiq_glue_handler *h)
 793 {
 794         struct fiq_debugger_state *state =
 795                 container_of(h, struct fiq_debugger_state, handler);
 796         if (state->pdata->uart_resume)
 797                 state->pdata->uart_resume(state->pdev);
 798 }
 799 #endif
 800
 801 #if defined(CONFIG_FIQ_DEBUGGER_CONSOLE)
 802 struct tty_driver *fiq_debugger_console_device(struct console *co, int *index)
 803 {
 804         *index = co->index;
 805         return fiq_tty_driver;
 806 }
 807
 808 static void fiq_debugger_console_write(struct console *co,
 809                                 const char *s, unsigned int count)
 810 {
 811         struct fiq_debugger_state *state;
 812         unsigned long flags;
 813
 814         state = container_of(co, struct fiq_debugger_state, console);
 815
 816         if (!state->console_enable && !state->syslog_dumping)
 817                 return;
 818
 819 #ifdef CONFIG_RK_CONSOLE_THREAD
 820         if (state->pdata->console_write) {
 821                 state->pdata->console_write(state->pdev, s, count);
 822                 return;
 823         }
 824 #endif
 825
 826         fiq_debugger_uart_enable(state);
 827         spin_lock_irqsave(&state->console_lock, flags);
 828         while (count--) {
 829                 if (*s == '\n')
 830                         fiq_debugger_putc(state, '\r');
 831                 fiq_debugger_putc(state, *s++);
 832         }
 833         fiq_debugger_uart_flush(state);
 834         spin_unlock_irqrestore(&state->console_lock, flags);
 835         fiq_debugger_uart_disable(state);
 836 }
 837
 838 static struct console fiq_debugger_console = {
 839         .name = "ttyFIQ",
 840         .device = fiq_debugger_console_device,
 841         .write = fiq_debugger_console_write,
 842         .flags = CON_PRINTBUFFER | CON_ANYTIME | CON_ENABLED,
 843 };
 844
 845 int fiq_tty_open(struct tty_struct *tty, struct file *filp)
 846 {
 847         int line = tty->index;
 848         struct fiq_debugger_state **states = tty->driver->driver_state;
 849         struct fiq_debugger_state *state = states[line];
 850
 851         return tty_port_open(&state->tty_port, tty, filp);
 852 }
 853
 854 void fiq_tty_close(struct tty_struct *tty, struct file *filp)
 855 {
 856         tty_port_close(tty->port, tty, filp);
 857 }
 858
 859 int  fiq_tty_write(struct tty_struct *tty, const unsigned char *buf, int count)
 860 {
 861         int i;
 862         int line = tty->index;
 863         struct fiq_debugger_state **states = tty->driver->driver_state;
 864         struct fiq_debugger_state *state = states[line];
 865
 866         if (!state->console_enable)
 867                 return count;
 868
 869         fiq_debugger_uart_enable(state);
 870         spin_lock_irq(&state->console_lock);
 871         for (i = 0; i < count; i++)
 872                 fiq_debugger_putc(state, *buf++);
 873         spin_unlock_irq(&state->console_lock);
 874         fiq_debugger_uart_disable(state);
 875
 876         return count;
 877 }
 878
 879 int  fiq_tty_write_room(struct tty_struct *tty)
 880 {
 881         return 16;
 882 }
 883
 884 #ifdef CONFIG_CONSOLE_POLL
 885 static int fiq_tty_poll_init(struct tty_driver *driver, int line, char *options)
 886 {
 887         return 0;
 888 }
 889
 890 static int fiq_tty_poll_get_char(struct tty_driver *driver, int line)
 891 {
 892         struct fiq_debugger_state **states = driver->driver_state;
 893         struct fiq_debugger_state *state = states[line];
 894         int c = NO_POLL_CHAR;
 895
 896         fiq_debugger_uart_enable(state);
 897         if (fiq_debugger_have_fiq(state)) {
 898                 int count = fiq_debugger_ringbuf_level(state->tty_rbuf);
 899                 if (count > 0) {
 900                         c = fiq_debugger_ringbuf_peek(state->tty_rbuf, 0);
 901                         fiq_debugger_ringbuf_consume(state->tty_rbuf, 1);
 902                 }
 903         } else {
 904                 c = fiq_debugger_getc(state);
 905                 if (c == FIQ_DEBUGGER_NO_CHAR)
 906                         c = NO_POLL_CHAR;
 907         }
 908         fiq_debugger_uart_disable(state);
 909
 910         return c;
 911 }
 912
 913 static void fiq_tty_poll_put_char(struct tty_driver *driver, int line, char ch)
 914 {
 915         struct fiq_debugger_state **states = driver->driver_state;
 916         struct fiq_debugger_state *state = states[line];
 917         fiq_debugger_uart_enable(state);
 918         fiq_debugger_putc(state, ch);
 919         fiq_debugger_uart_disable(state);
 920 }
 921 #endif
 922
 923 static const struct tty_port_operations fiq_tty_port_ops;
 924
 925 static const struct tty_operations fiq_tty_driver_ops = {
 926         .write = fiq_tty_write,
 927         .write_room = fiq_tty_write_room,
 928         .open = fiq_tty_open,
 929         .close = fiq_tty_close,
 930 #ifdef CONFIG_CONSOLE_POLL
 931         .poll_init = fiq_tty_poll_init,
 932         .poll_get_char = fiq_tty_poll_get_char,
 933         .poll_put_char = fiq_tty_poll_put_char,
 934 #endif
 935 };
 936
 937 static int fiq_debugger_tty_init(void)
 938 {
 939         int ret;
 940         struct fiq_debugger_state **states = NULL;
 941
 942         states = kzalloc(sizeof(*states) * MAX_FIQ_DEBUGGER_PORTS, GFP_KERNEL);
 943         if (!states) {
 944                 pr_err("Failed to allocate fiq debugger state structres\n");
 945                 return -ENOMEM;
 946         }
 947
 948         fiq_tty_driver = alloc_tty_driver(MAX_FIQ_DEBUGGER_PORTS);
 949         if (!fiq_tty_driver) {
 950                 pr_err("Failed to allocate fiq debugger tty\n");
 951                 ret = -ENOMEM;
 952                 goto err_free_state;
 953         }
 954
 955         fiq_tty_driver->owner           = THIS_MODULE;
 956         fiq_tty_driver->driver_name     = "fiq-debugger";
 957         fiq_tty_driver->name            = "ttyFIQ";
 958         fiq_tty_driver->type            = TTY_DRIVER_TYPE_SERIAL;
 959         fiq_tty_driver->subtype         = SERIAL_TYPE_NORMAL;
 960         fiq_tty_driver->init_termios    = tty_std_termios;
 961         fiq_tty_driver->flags           = TTY_DRIVER_REAL_RAW |
 962                                           TTY_DRIVER_DYNAMIC_DEV;
 963         fiq_tty_driver->driver_state    = states;
 964
 965         fiq_tty_driver->init_termios.c_cflag =
 966                                         B115200 | CS8 | CREAD | HUPCL | CLOCAL;
 967         fiq_tty_driver->init_termios.c_ispeed = 115200;
 968         fiq_tty_driver->init_termios.c_ospeed = 115200;
 969
 970         tty_set_operations(fiq_tty_driver, &fiq_tty_driver_ops);
 971
 972         ret = tty_register_driver(fiq_tty_driver);
 973         if (ret) {
 974                 pr_err("Failed to register fiq tty: %d\n", ret);
 975                 goto err_free_tty;
 976         }
 977
 978         pr_info("Registered FIQ tty driver\n");
 979         return 0;
 980
 981 err_free_tty:
 982         put_tty_driver(fiq_tty_driver);
 983         fiq_tty_driver = NULL;
 984 err_free_state:
 985         kfree(states);
 986         return ret;
 987 }
 988
 989 static int fiq_debugger_tty_init_one(struct fiq_debugger_state *state)
 990 {
 991         int ret;
 992         struct device *tty_dev;
 993         struct fiq_debugger_state **states = fiq_tty_driver->driver_state;
 994
 995         states[state->pdev->id] = state;
 996
 997         state->tty_rbuf = fiq_debugger_ringbuf_alloc(1024);
 998         if (!state->tty_rbuf) {
 999                 pr_err("Failed to allocate fiq debugger ringbuf\n");
1000                 ret = -ENOMEM;
1001                 goto err;
1002         }
1003
1004         tty_port_init(&state->tty_port);
1005         state->tty_port.ops = &fiq_tty_port_ops;
1006
1007         tty_dev = tty_port_register_device(&state->tty_port, fiq_tty_driver,
1008                                            state->pdev->id, &state->pdev->dev);
1009         if (IS_ERR(tty_dev)) {
1010                 pr_err("Failed to register fiq debugger tty device\n");
1011                 ret = PTR_ERR(tty_dev);
1012                 goto err;
1013         }
1014
1015         device_set_wakeup_capable(tty_dev, 1);
1016
1017         pr_info("Registered fiq debugger ttyFIQ%d\n", state->pdev->id);
1018
1019         return 0;
1020
1021 err:
1022         fiq_debugger_ringbuf_free(state->tty_rbuf);
1023         state->tty_rbuf = NULL;
1024         return ret;
1025 }
1026 #endif
1027
1028 static int fiq_debugger_dev_suspend(struct device *dev)
1029 {
1030         struct platform_device *pdev = to_platform_device(dev);
1031         struct fiq_debugger_state *state = platform_get_drvdata(pdev);
1032
1033         if (state->pdata->uart_dev_suspend)
1034                 return state->pdata->uart_dev_suspend(pdev);
1035         return 0;
1036 }
1037
1038 static int fiq_debugger_dev_resume(struct device *dev)
1039 {
1040         struct platform_device *pdev = to_platform_device(dev);
1041         struct fiq_debugger_state *state = platform_get_drvdata(pdev);
1042
1043         if (state->pdata->uart_dev_resume)
1044                 return state->pdata->uart_dev_resume(pdev);
1045         return 0;
1046 }
1047
1048 static int fiq_debugger_probe(struct platform_device *pdev)
1049 {
1050         int ret;
1051         struct fiq_debugger_pdata *pdata = dev_get_platdata(&pdev->dev);
1052         struct fiq_debugger_state *state;
1053         int fiq;
1054         int uart_irq;
1055
1056         if (pdev->id >= MAX_FIQ_DEBUGGER_PORTS)
1057                 return -EINVAL;
1058
1059         if (!pdata->uart_getc || !pdata->uart_putc)
1060                 return -EINVAL;
1061         if ((pdata->uart_enable && !pdata->uart_disable) ||
1062             (!pdata->uart_enable && pdata->uart_disable))
1063                 return -EINVAL;
1064
1065         fiq = platform_get_irq_byname(pdev, "fiq");
1066         uart_irq = platform_get_irq_byname(pdev, "uart_irq");
1067
1068         /* uart_irq mode and fiq mode are mutually exclusive, but one of them
1069          * is required */
1070         if ((uart_irq < 0 && fiq < 0) || (uart_irq >= 0 && fiq >= 0))
1071                 return -EINVAL;
1072         if (fiq >= 0 && !pdata->fiq_enable)
1073                 return -EINVAL;
1074
1075         state = kzalloc(sizeof(*state), GFP_KERNEL);
1076         state->output.printf = fiq_debugger_printf;
1077         setup_timer(&state->sleep_timer, fiq_debugger_sleep_timer_expired,
1078                     (unsigned long)state);
1079         state->pdata = pdata;
1080         state->pdev = pdev;
1081         state->no_sleep = initial_no_sleep;
1082         state->debug_enable = initial_debug_enable;
1083         state->console_enable = initial_console_enable;
1084
1085         state->fiq = fiq;
1086         state->uart_irq = uart_irq;
1087         state->signal_irq = platform_get_irq_byname(pdev, "signal");
1088         state->wakeup_irq = platform_get_irq_byname(pdev, "wakeup");
1089
1090         INIT_WORK(&state->work, fiq_debugger_work);
1091         spin_lock_init(&state->work_lock);
1092
1093         platform_set_drvdata(pdev, state);
1094
1095         spin_lock_init(&state->sleep_timer_lock);
1096
1097         if (state->wakeup_irq < 0 && fiq_debugger_have_fiq(state))
1098                 state->no_sleep = true;
1099         state->ignore_next_wakeup_irq = !state->no_sleep;
1100
1101         wake_lock_init(&state->debugger_wake_lock,
1102                         WAKE_LOCK_SUSPEND, "serial-debug");
1103
1104         state->clk = clk_get(&pdev->dev, NULL);
1105         if (IS_ERR(state->clk))
1106                 state->clk = NULL;
1107
1108         /* do not call pdata->uart_enable here since uart_init may still
1109          * need to do some initialization before uart_enable can work.
1110          * So, only try to manage the clock during init.
1111          */
1112         if (state->clk)
1113                 clk_enable(state->clk);
1114
1115         if (pdata->uart_init) {
1116                 ret = pdata->uart_init(pdev);
1117                 if (ret)
1118                         goto err_uart_init;
1119         }
1120
1121         fiq_debugger_printf_nfiq(state,
1122                                 "<hit enter %sto activate fiq debugger>\n",
1123                                 state->no_sleep ? "" : "twice ");
1124
1125 #ifdef CONFIG_FIQ_GLUE
1126         if (fiq_debugger_have_fiq(state)) {
1127                 state->handler.fiq = fiq_debugger_fiq;
1128                 state->handler.resume = fiq_debugger_resume;
1129                 ret = fiq_glue_register_handler(&state->handler);
1130                 if (ret) {
1131                         pr_err("%s: could not install fiq handler\n", __func__);
1132                         goto err_register_irq;
1133                 }
1134
1135                 pdata->fiq_enable(pdev, state->fiq, 1);
1136         } else
1137 #endif
1138         {
1139                 ret = request_irq(state->uart_irq, fiq_debugger_uart_irq,
1140                                   IRQF_NO_SUSPEND, "debug", state);
1141                 if (ret) {
1142                         pr_err("%s: could not install irq handler\n", __func__);
1143                         goto err_register_irq;
1144                 }
1145
1146                 /* for irq-only mode, we want this irq to wake us up, if it
1147                  * can.
1148                  */
1149                 enable_irq_wake(state->uart_irq);
1150         }
1151
1152         if (state->clk)
1153                 clk_disable(state->clk);
1154
1155         if (state->signal_irq >= 0) {
1156                 ret = request_irq(state->signal_irq, fiq_debugger_signal_irq,
1157                           IRQF_TRIGGER_RISING, "debug-signal", state);
1158                 if (ret)
1159                         pr_err("serial_debugger: could not install signal_irq");
1160         }
1161
1162         if (state->wakeup_irq >= 0) {
1163                 ret = request_irq(state->wakeup_irq,
1164                                   fiq_debugger_wakeup_irq_handler,
1165                                   IRQF_TRIGGER_FALLING,
1166                                   "debug-wakeup", state);
1167                 if (ret) {
1168                         pr_err("serial_debugger: "
1169                                 "could not install wakeup irq\n");
1170                         state->wakeup_irq = -1;
1171                 } else {
1172                         ret = enable_irq_wake(state->wakeup_irq);
1173                         if (ret) {
1174                                 pr_err("serial_debugger: "
1175                                         "could not enable wakeup\n");
1176                                 state->wakeup_irq_no_set_wake = true;
1177                         }
1178                 }
1179         }
1180         if (state->no_sleep)
1181                 fiq_debugger_handle_wakeup(state);
1182
1183 #if defined(CONFIG_FIQ_DEBUGGER_CONSOLE)
1184         spin_lock_init(&state->console_lock);
1185         state->console = fiq_debugger_console;
1186         state->console.index = pdev->id;
1187         if (!console_set_on_cmdline)
1188                 add_preferred_console(state->console.name,
1189                         state->console.index, NULL);
1190         register_console(&state->console);
1191         fiq_debugger_tty_init_one(state);
1192 #endif
1193         return 0;
1194
1195 err_register_irq:
1196         if (pdata->uart_free)
1197                 pdata->uart_free(pdev);
1198 err_uart_init:
1199         if (state->clk)
1200                 clk_disable(state->clk);
1201         if (state->clk)
1202                 clk_put(state->clk);
1203         wake_lock_destroy(&state->debugger_wake_lock);
1204         platform_set_drvdata(pdev, NULL);
1205         kfree(state);
1206         return ret;
1207 }
1208
1209 static const struct dev_pm_ops fiq_debugger_dev_pm_ops = {
1210         .suspend        = fiq_debugger_dev_suspend,
1211         .resume         = fiq_debugger_dev_resume,
1212 };
1213
1214 static struct platform_driver fiq_debugger_driver = {
1215         .probe  = fiq_debugger_probe,
1216         .driver = {
1217                 .name   = "fiq_debugger",
1218                 .pm     = &fiq_debugger_dev_pm_ops,
1219         },
1220 };
1221
1222 #if defined(CONFIG_FIQ_DEBUGGER_UART_OVERLAY)
1223 int fiq_debugger_uart_overlay(void)
1224 {
1225         struct device_node *onp = of_find_node_by_path("/uart_overlay@0");
1226         int ret;
1227
1228         if (!onp) {
1229                 pr_err("serial_debugger: uart overlay not found\n");
1230                 return -ENODEV;
1231         }
1232
1233         ret = of_overlay_create(onp);
1234         if (ret < 0) {
1235                 pr_err("serial_debugger: fail to create overlay: %d\n", ret);
1236                 of_node_put(onp);
1237                 return ret;
1238         }
1239
1240         pr_info("serial_debugger: uart overlay applied\n");
1241         return 0;
1242 }
1243 #endif
1244
1245 static int __init fiq_debugger_init(void)
1246 {
1247         if (fiq_debugger_disable) {
1248                 pr_err("serial_debugger: disabled\n");
1249                 return -ENODEV;
1250         }
1251 #if defined(CONFIG_FIQ_DEBUGGER_CONSOLE)
1252         fiq_debugger_tty_init();
1253 #endif
1254 #if defined(CONFIG_FIQ_DEBUGGER_UART_OVERLAY)
1255         fiq_debugger_uart_overlay();
1256 #endif
1257         return platform_driver_register(&fiq_debugger_driver);
1258 }
1259
1260 postcore_initcall(fiq_debugger_init);