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 #include <asm/stacktrace.h>
  42
  43 #include <linux/uaccess.h>
  44
  45 #include "fiq_debugger.h"
  46 #include "fiq_debugger_ringbuf.h"
  47
  48 #define DEBUG_MAX 64
  49 #define MAX_UNHANDLED_FIQ_COUNT 1000000
  50
  51 #define MAX_FIQ_DEBUGGER_PORTS 4
  52
  53 #define THREAD_INFO(sp) ((struct thread_info *) \
  54                 ((unsigned long)(sp) & ~(THREAD_SIZE - 1)))
  55
  56 struct fiq_debugger_state {
  57 #ifdef CONFIG_FIQ_GLUE
  58         struct fiq_glue_handler handler;
  59 #endif
  60
  61         int fiq;
  62         int uart_irq;
  63         int signal_irq;
  64         int wakeup_irq;
  65         bool wakeup_irq_no_set_wake;
  66         struct clk *clk;
  67         struct fiq_debugger_pdata *pdata;
  68         struct platform_device *pdev;
  69
  70         char debug_cmd[DEBUG_MAX];
  71         int debug_busy;
  72         int debug_abort;
  73
  74         char debug_buf[DEBUG_MAX];
  75         int debug_count;
  76
  77         bool no_sleep;
  78         bool debug_enable;
  79         bool ignore_next_wakeup_irq;
  80         struct timer_list sleep_timer;
  81         spinlock_t sleep_timer_lock;
  82         bool uart_enabled;
  83         struct wake_lock debugger_wake_lock;
  84         bool console_enable;
  85         int current_cpu;
  86         atomic_t unhandled_fiq_count;
  87         bool in_fiq;
  88
  89         struct work_struct work;
  90         spinlock_t work_lock;
  91         char work_cmd[DEBUG_MAX];
  92
  93 #ifdef CONFIG_FIQ_DEBUGGER_CONSOLE
  94         spinlock_t console_lock;
  95         struct console console;
  96         struct tty_port tty_port;
  97         struct fiq_debugger_ringbuf *tty_rbuf;
  98         bool syslog_dumping;
  99 #endif
 100
 101         unsigned int last_irqs[NR_IRQS];
 102         unsigned int last_local_timer_irqs[NR_CPUS];
 103 };
 104
 105 #ifdef CONFIG_FIQ_DEBUGGER_CONSOLE
 106 struct tty_driver *fiq_tty_driver;
 107 #endif
 108
 109 #ifdef CONFIG_FIQ_DEBUGGER_NO_SLEEP
 110 static bool initial_no_sleep = true;
 111 #else
 112 static bool initial_no_sleep;
 113 #endif
 114
 115 #ifdef CONFIG_FIQ_DEBUGGER_CONSOLE_DEFAULT_ENABLE
 116 static bool initial_debug_enable = true;
 117 static bool initial_console_enable = true;
 118 #else
 119 static bool initial_debug_enable;
 120 static bool initial_console_enable;
 121 #endif
 122
 123 static bool fiq_kgdb_enable;
 124
 125 module_param_named(no_sleep, initial_no_sleep, bool, 0644);
 126 module_param_named(debug_enable, initial_debug_enable, bool, 0644);
 127 module_param_named(console_enable, initial_console_enable, bool, 0644);
 128 module_param_named(kgdb_enable, fiq_kgdb_enable, bool, 0644);
 129
 130 #ifdef CONFIG_FIQ_DEBUGGER_WAKEUP_IRQ_ALWAYS_ON
 131 static inline
 132 void fiq_debugger_enable_wakeup_irq(struct fiq_debugger_state *state) {}
 133 static inline
 134 void fiq_debugger_disable_wakeup_irq(struct fiq_debugger_state *state) {}
 135 #else
 136 static inline
 137 void fiq_debugger_enable_wakeup_irq(struct fiq_debugger_state *state)
 138 {
 139         if (state->wakeup_irq < 0)
 140                 return;
 141         enable_irq(state->wakeup_irq);
 142         if (!state->wakeup_irq_no_set_wake)
 143                 enable_irq_wake(state->wakeup_irq);
 144 }
 145 static inline
 146 void fiq_debugger_disable_wakeup_irq(struct fiq_debugger_state *state)
 147 {
 148         if (state->wakeup_irq < 0)
 149                 return;
 150         disable_irq_nosync(state->wakeup_irq);
 151         if (!state->wakeup_irq_no_set_wake)
 152                 disable_irq_wake(state->wakeup_irq);
 153 }
 154 #endif
 155
 156 static inline bool fiq_debugger_have_fiq(struct fiq_debugger_state *state)
 157 {
 158         return (state->fiq >= 0);
 159 }
 160
 161 #ifdef CONFIG_FIQ_GLUE
 162 static void fiq_debugger_force_irq(struct fiq_debugger_state *state)
 163 {
 164         unsigned int irq = state->signal_irq;
 165
 166         if (WARN_ON(!fiq_debugger_have_fiq(state)))
 167                 return;
 168         if (state->pdata->force_irq) {
 169                 state->pdata->force_irq(state->pdev, irq);
 170         } else {
 171                 struct irq_chip *chip = irq_get_chip(irq);
 172                 if (chip && chip->irq_retrigger)
 173                         chip->irq_retrigger(irq_get_irq_data(irq));
 174         }
 175 }
 176 #endif
 177
 178 static void fiq_debugger_uart_enable(struct fiq_debugger_state *state)
 179 {
 180         if (state->clk)
 181                 clk_enable(state->clk);
 182         if (state->pdata->uart_enable)
 183                 state->pdata->uart_enable(state->pdev);
 184 }
 185
 186 static void fiq_debugger_uart_disable(struct fiq_debugger_state *state)
 187 {
 188         if (state->pdata->uart_disable)
 189                 state->pdata->uart_disable(state->pdev);
 190         if (state->clk)
 191                 clk_disable(state->clk);
 192 }
 193
 194 static void fiq_debugger_uart_flush(struct fiq_debugger_state *state)
 195 {
 196         if (state->pdata->uart_flush)
 197                 state->pdata->uart_flush(state->pdev);
 198 }
 199
 200 static void fiq_debugger_putc(struct fiq_debugger_state *state, char c)
 201 {
 202         state->pdata->uart_putc(state->pdev, c);
 203 }
 204
 205 static void fiq_debugger_puts(struct fiq_debugger_state *state, char *s)
 206 {
 207         unsigned c;
 208         while ((c = *s++)) {
 209                 if (c == '\n')
 210                         fiq_debugger_putc(state, '\r');
 211                 fiq_debugger_putc(state, c);
 212         }
 213 }
 214
 215 static void fiq_debugger_prompt(struct fiq_debugger_state *state)
 216 {
 217         fiq_debugger_puts(state, "debug> ");
 218 }
 219
 220 static void fiq_debugger_dump_kernel_log(struct fiq_debugger_state *state)
 221 {
 222         char buf[512];
 223         size_t len;
 224         struct kmsg_dumper dumper = { .active = true };
 225
 226
 227         kmsg_dump_rewind_nolock(&dumper);
 228         while (kmsg_dump_get_line_nolock(&dumper, true, buf,
 229                                          sizeof(buf) - 1, &len)) {
 230                 buf[len] = 0;
 231                 fiq_debugger_puts(state, buf);
 232         }
 233 }
 234
 235 static char *mode_name(unsigned cpsr)
 236 {
 237         switch (cpsr & MODE_MASK) {
 238         case USR_MODE: return "USR";
 239         case FIQ_MODE: return "FIQ";
 240         case IRQ_MODE: return "IRQ";
 241         case SVC_MODE: return "SVC";
 242         case ABT_MODE: return "ABT";
 243         case UND_MODE: return "UND";
 244         case SYSTEM_MODE: return "SYS";
 245         default: return "???";
 246         }
 247 }
 248
 249 static int fiq_debugger_printf(void *cookie, const char *fmt, ...)
 250 {
 251         struct fiq_debugger_state *state = cookie;
 252         char buf[256];
 253         va_list ap;
 254
 255         va_start(ap, fmt);
 256         vsnprintf(buf, sizeof(buf), fmt, ap);
 257         va_end(ap);
 258
 259         fiq_debugger_puts(state, buf);
 260         return state->debug_abort;
 261 }
 262
 263 /* Safe outside fiq context */
 264 static int fiq_debugger_printf_nfiq(void *cookie, const char *fmt, ...)
 265 {
 266         struct fiq_debugger_state *state = cookie;
 267         char buf[256];
 268         va_list ap;
 269         unsigned long irq_flags;
 270
 271         va_start(ap, fmt);
 272         vsnprintf(buf, 128, fmt, ap);
 273         va_end(ap);
 274
 275         local_irq_save(irq_flags);
 276         fiq_debugger_puts(state, buf);
 277         fiq_debugger_uart_flush(state);
 278         local_irq_restore(irq_flags);
 279         return state->debug_abort;
 280 }
 281
 282 static void fiq_debugger_dump_regs(struct fiq_debugger_state *state,
 283                 const struct pt_regs *regs)
 284 {
 285         fiq_debugger_printf(state,
 286                         " r0 %08x  r1 %08x  r2 %08x  r3 %08x\n",
 287                         regs->ARM_r0, regs->ARM_r1, regs->ARM_r2, regs->ARM_r3);
 288         fiq_debugger_printf(state,
 289                         " r4 %08x  r5 %08x  r6 %08x  r7 %08x\n",
 290                         regs->ARM_r4, regs->ARM_r5, regs->ARM_r6, regs->ARM_r7);
 291         fiq_debugger_printf(state,
 292                         " r8 %08x  r9 %08x r10 %08x r11 %08x  mode %s\n",
 293                         regs->ARM_r8, regs->ARM_r9, regs->ARM_r10, regs->ARM_fp,
 294                         mode_name(regs->ARM_cpsr));
 295         fiq_debugger_printf(state,
 296                         " ip %08x  sp %08x  lr %08x  pc %08x cpsr %08x\n",
 297                         regs->ARM_ip, regs->ARM_sp, regs->ARM_lr, regs->ARM_pc,
 298                         regs->ARM_cpsr);
 299 }
 300
 301 struct mode_regs {
 302         unsigned long sp_svc;
 303         unsigned long lr_svc;
 304         unsigned long spsr_svc;
 305
 306         unsigned long sp_abt;
 307         unsigned long lr_abt;
 308         unsigned long spsr_abt;
 309
 310         unsigned long sp_und;
 311         unsigned long lr_und;
 312         unsigned long spsr_und;
 313
 314         unsigned long sp_irq;
 315         unsigned long lr_irq;
 316         unsigned long spsr_irq;
 317
 318         unsigned long r8_fiq;
 319         unsigned long r9_fiq;
 320         unsigned long r10_fiq;
 321         unsigned long r11_fiq;
 322         unsigned long r12_fiq;
 323         unsigned long sp_fiq;
 324         unsigned long lr_fiq;
 325         unsigned long spsr_fiq;
 326 };
 327
 328 void __naked get_mode_regs(struct mode_regs *regs)
 329 {
 330         asm volatile (
 331         "mrs    r1, cpsr\n"
 332         "msr    cpsr_c, #0xd3 @(SVC_MODE | PSR_I_BIT | PSR_F_BIT)\n"
 333         "stmia  r0!, {r13 - r14}\n"
 334         "mrs    r2, spsr\n"
 335         "msr    cpsr_c, #0xd7 @(ABT_MODE | PSR_I_BIT | PSR_F_BIT)\n"
 336         "stmia  r0!, {r2, r13 - r14}\n"
 337         "mrs    r2, spsr\n"
 338         "msr    cpsr_c, #0xdb @(UND_MODE | PSR_I_BIT | PSR_F_BIT)\n"
 339         "stmia  r0!, {r2, r13 - r14}\n"
 340         "mrs    r2, spsr\n"
 341         "msr    cpsr_c, #0xd2 @(IRQ_MODE | PSR_I_BIT | PSR_F_BIT)\n"
 342         "stmia  r0!, {r2, r13 - r14}\n"
 343         "mrs    r2, spsr\n"
 344         "msr    cpsr_c, #0xd1 @(FIQ_MODE | PSR_I_BIT | PSR_F_BIT)\n"
 345         "stmia  r0!, {r2, r8 - r14}\n"
 346         "mrs    r2, spsr\n"
 347         "stmia  r0!, {r2}\n"
 348         "msr    cpsr_c, r1\n"
 349         "bx     lr\n");
 350 }
 351
 352
 353 static void fiq_debugger_dump_allregs(struct fiq_debugger_state *state,
 354                 const struct pt_regs *regs)
 355 {
 356         struct mode_regs mode_regs;
 357         unsigned long mode = regs->ARM_cpsr & MODE_MASK;
 358
 359         fiq_debugger_dump_regs(state, regs);
 360         get_mode_regs(&mode_regs);
 361
 362         fiq_debugger_printf(state,
 363                         "%csvc: sp %08x  lr %08x  spsr %08x\n",
 364                         mode == SVC_MODE ? '*' : ' ',
 365                         mode_regs.sp_svc, mode_regs.lr_svc, mode_regs.spsr_svc);
 366         fiq_debugger_printf(state,
 367                         "%cabt: sp %08x  lr %08x  spsr %08x\n",
 368                         mode == ABT_MODE ? '*' : ' ',
 369                         mode_regs.sp_abt, mode_regs.lr_abt, mode_regs.spsr_abt);
 370         fiq_debugger_printf(state,
 371                         "%cund: sp %08x  lr %08x  spsr %08x\n",
 372                         mode == UND_MODE ? '*' : ' ',
 373                         mode_regs.sp_und, mode_regs.lr_und, mode_regs.spsr_und);
 374         fiq_debugger_printf(state,
 375                         "%cirq: sp %08x  lr %08x  spsr %08x\n",
 376                         mode == IRQ_MODE ? '*' : ' ',
 377                         mode_regs.sp_irq, mode_regs.lr_irq, mode_regs.spsr_irq);
 378         fiq_debugger_printf(state,
 379                         "%cfiq: r8 %08x  r9 %08x  r10 %08x  r11 %08x  r12 %08x\n",
 380                         mode == FIQ_MODE ? '*' : ' ',
 381                         mode_regs.r8_fiq, mode_regs.r9_fiq, mode_regs.r10_fiq,
 382                         mode_regs.r11_fiq, mode_regs.r12_fiq);
 383         fiq_debugger_printf(state,
 384                         " fiq: sp %08x  lr %08x  spsr %08x\n",
 385                         mode_regs.sp_fiq, mode_regs.lr_fiq, mode_regs.spsr_fiq);
 386 }
 387
 388 static void fiq_debugger_dump_irqs(struct fiq_debugger_state *state)
 389 {
 390         int n;
 391         struct irq_desc *desc;
 392
 393         fiq_debugger_printf(state,
 394                         "irqnr       total  since-last   status  name\n");
 395         for_each_irq_desc(n, desc) {
 396                 struct irqaction *act = desc->action;
 397                 if (!act && !kstat_irqs(n))
 398                         continue;
 399                 fiq_debugger_printf(state, "%5d: %10u %11u %8x  %s\n", n,
 400                         kstat_irqs(n),
 401                         kstat_irqs(n) - state->last_irqs[n],
 402                         desc->status_use_accessors,
 403                         (act && act->name) ? act->name : "???");
 404                 state->last_irqs[n] = kstat_irqs(n);
 405         }
 406 }
 407
 408 struct stacktrace_state {
 409         struct fiq_debugger_state *state;
 410         unsigned int depth;
 411 };
 412
 413 static int report_trace(struct stackframe *frame, void *d)
 414 {
 415         struct stacktrace_state *sts = d;
 416
 417         if (sts->depth) {
 418                 fiq_debugger_printf(sts->state,
 419                         "  pc: %p (%pF), lr %p (%pF), sp %p, fp %p\n",
 420                         frame->pc, frame->pc, frame->lr, frame->lr,
 421                         frame->sp, frame->fp);
 422                 sts->depth--;
 423                 return 0;
 424         }
 425         fiq_debugger_printf(sts->state, "  ...\n");
 426
 427         return sts->depth == 0;
 428 }
 429
 430 struct frame_tail {
 431         struct frame_tail *fp;
 432         unsigned long sp;
 433         unsigned long lr;
 434 } __attribute__((packed));
 435
 436 static struct frame_tail *user_backtrace(struct fiq_debugger_state *state,
 437                                         struct frame_tail *tail)
 438 {
 439         struct frame_tail buftail[2];
 440
 441         /* Also check accessibility of one struct frame_tail beyond */
 442         if (!access_ok(VERIFY_READ, tail, sizeof(buftail))) {
 443                 fiq_debugger_printf(state, "  invalid frame pointer %p\n",
 444                                 tail);
 445                 return NULL;
 446         }
 447         if (__copy_from_user_inatomic(buftail, tail, sizeof(buftail))) {
 448                 fiq_debugger_printf(state,
 449                         "  failed to copy frame pointer %p\n", tail);
 450                 return NULL;
 451         }
 452
 453         fiq_debugger_printf(state, "  %p\n", buftail[0].lr);
 454
 455         /* frame pointers should strictly progress back up the stack
 456          * (towards higher addresses) */
 457         if (tail >= buftail[0].fp)
 458                 return NULL;
 459
 460         return buftail[0].fp-1;
 461 }
 462
 463 void fiq_debugger_dump_stacktrace(struct fiq_debugger_state *state,
 464                 const struct pt_regs *regs, unsigned int depth, void *ssp)
 465 {
 466         struct frame_tail *tail;
 467         struct thread_info *real_thread_info = THREAD_INFO(ssp);
 468         struct stacktrace_state sts;
 469
 470         sts.depth = depth;
 471         sts.state = state;
 472         *current_thread_info() = *real_thread_info;
 473
 474         if (!current)
 475                 fiq_debugger_printf(state, "current NULL\n");
 476         else
 477                 fiq_debugger_printf(state, "pid: %d  comm: %s\n",
 478                         current->pid, current->comm);
 479         fiq_debugger_dump_regs(state, regs);
 480
 481         if (!user_mode(regs)) {
 482                 struct stackframe frame;
 483                 frame.fp = regs->ARM_fp;
 484                 frame.sp = regs->ARM_sp;
 485                 frame.lr = regs->ARM_lr;
 486                 frame.pc = regs->ARM_pc;
 487                 fiq_debugger_printf(state,
 488                         "  pc: %p (%pF), lr %p (%pF), sp %p, fp %p\n",
 489                         regs->ARM_pc, regs->ARM_pc, regs->ARM_lr, regs->ARM_lr,
 490                         regs->ARM_sp, regs->ARM_fp);
 491                 walk_stackframe(&frame, report_trace, &sts);
 492                 return;
 493         }
 494
 495         tail = ((struct frame_tail *) regs->ARM_fp) - 1;
 496         while (depth-- && tail && !((unsigned long) tail & 3))
 497                 tail = user_backtrace(state, tail);
 498 }
 499
 500 static void fiq_debugger_do_ps(struct fiq_debugger_state *state)
 501 {
 502         struct task_struct *g;
 503         struct task_struct *p;
 504         unsigned task_state;
 505         static const char stat_nam[] = "RSDTtZX";
 506
 507         fiq_debugger_printf(state, "pid   ppid  prio task            pc\n");
 508         read_lock(&tasklist_lock);
 509         do_each_thread(g, p) {
 510                 task_state = p->state ? __ffs(p->state) + 1 : 0;
 511                 fiq_debugger_printf(state,
 512                              "%5d %5d %4d ", p->pid, p->parent->pid, p->prio);
 513                 fiq_debugger_printf(state, "%-13.13s %c", p->comm,
 514                              task_state >= sizeof(stat_nam) ? '?' : stat_nam[task_state]);
 515                 if (task_state == TASK_RUNNING)
 516                         fiq_debugger_printf(state, " running\n");
 517                 else
 518                         fiq_debugger_printf(state, " %08lx\n",
 519                                         thread_saved_pc(p));
 520         } while_each_thread(g, p);
 521         read_unlock(&tasklist_lock);
 522 }
 523
 524 #ifdef CONFIG_FIQ_DEBUGGER_CONSOLE
 525 static void fiq_debugger_begin_syslog_dump(struct fiq_debugger_state *state)
 526 {
 527         state->syslog_dumping = true;
 528 }
 529
 530 static void fiq_debugger_end_syslog_dump(struct fiq_debugger_state *state)
 531 {
 532         state->syslog_dumping = false;
 533 }
 534 #else
 535 extern int do_syslog(int type, char __user *bug, int count);
 536 static void fiq_debugger_begin_syslog_dump(struct fiq_debugger_state *state)
 537 {
 538         do_syslog(5 /* clear */, NULL, 0);
 539 }
 540
 541 static void fiq_debugger_end_syslog_dump(struct fiq_debugger_state *state)
 542 {
 543         fiq_debugger_dump_kernel_log(state);
 544 }
 545 #endif
 546
 547 static void fiq_debugger_do_sysrq(struct fiq_debugger_state *state, char rq)
 548 {
 549         if ((rq == 'g' || rq == 'G') && !fiq_kgdb_enable) {
 550                 fiq_debugger_printf(state, "sysrq-g blocked\n");
 551                 return;
 552         }
 553         fiq_debugger_begin_syslog_dump(state);
 554         handle_sysrq(rq);
 555         fiq_debugger_end_syslog_dump(state);
 556 }
 557
 558 #ifdef CONFIG_KGDB
 559 static void fiq_debugger_do_kgdb(struct fiq_debugger_state *state)
 560 {
 561         if (!fiq_kgdb_enable) {
 562                 fiq_debugger_printf(state, "kgdb through fiq debugger not enabled\n");
 563                 return;
 564         }
 565
 566         fiq_debugger_printf(state, "enabling console and triggering kgdb\n");
 567         state->console_enable = true;
 568         handle_sysrq('g');
 569 }
 570 #endif
 571
 572 static void fiq_debugger_schedule_work(struct fiq_debugger_state *state,
 573                 char *cmd)
 574 {
 575         unsigned long flags;
 576
 577         spin_lock_irqsave(&state->work_lock, flags);
 578         if (state->work_cmd[0] != '\0') {
 579                 fiq_debugger_printf(state, "work command processor busy\n");
 580                 spin_unlock_irqrestore(&state->work_lock, flags);
 581                 return;
 582         }
 583
 584         strlcpy(state->work_cmd, cmd, sizeof(state->work_cmd));
 585         spin_unlock_irqrestore(&state->work_lock, flags);
 586
 587         schedule_work(&state->work);
 588 }
 589
 590 static void fiq_debugger_work(struct work_struct *work)
 591 {
 592         struct fiq_debugger_state *state;
 593         char work_cmd[DEBUG_MAX];
 594         char *cmd;
 595         unsigned long flags;
 596
 597         state = container_of(work, struct fiq_debugger_state, work);
 598
 599         spin_lock_irqsave(&state->work_lock, flags);
 600
 601         strlcpy(work_cmd, state->work_cmd, sizeof(work_cmd));
 602         state->work_cmd[0] = '\0';
 603
 604         spin_unlock_irqrestore(&state->work_lock, flags);
 605
 606         cmd = work_cmd;
 607         if (!strncmp(cmd, "reboot", 6)) {
 608                 cmd += 6;
 609                 while (*cmd == ' ')
 610                         cmd++;
 611                 if (cmd != '\0')
 612                         kernel_restart(cmd);
 613                 else
 614                         kernel_restart(NULL);
 615         } else {
 616                 fiq_debugger_printf(state, "unknown work command '%s'\n",
 617                                 work_cmd);
 618         }
 619 }
 620
 621 /* This function CANNOT be called in FIQ context */
 622 static void fiq_debugger_irq_exec(struct fiq_debugger_state *state, char *cmd)
 623 {
 624         if (!strcmp(cmd, "ps"))
 625                 fiq_debugger_do_ps(state);
 626         if (!strcmp(cmd, "sysrq"))
 627                 fiq_debugger_do_sysrq(state, 'h');
 628         if (!strncmp(cmd, "sysrq ", 6))
 629                 fiq_debugger_do_sysrq(state, cmd[6]);
 630 #ifdef CONFIG_KGDB
 631         if (!strcmp(cmd, "kgdb"))
 632                 fiq_debugger_do_kgdb(state);
 633 #endif
 634         if (!strncmp(cmd, "reboot", 6))
 635                 fiq_debugger_schedule_work(state, cmd);
 636 }
 637
 638 static void fiq_debugger_help(struct fiq_debugger_state *state)
 639 {
 640         fiq_debugger_printf(state,
 641                                 "FIQ Debugger commands:\n"
 642                                 " pc            PC status\n"
 643                                 " regs          Register dump\n"
 644                                 " allregs       Extended Register dump\n"
 645                                 " bt            Stack trace\n"
 646                                 " reboot [<c>]  Reboot with command <c>\n"
 647                                 " reset [<c>]   Hard reset with command <c>\n"
 648                                 " irqs          Interupt status\n"
 649                                 " kmsg          Kernel log\n"
 650                                 " version       Kernel version\n");
 651         fiq_debugger_printf(state,
 652                                 " sleep         Allow sleep while in FIQ\n"
 653                                 " nosleep       Disable sleep while in FIQ\n"
 654                                 " console       Switch terminal to console\n"
 655                                 " cpu           Current CPU\n"
 656                                 " cpu <number>  Switch to CPU<number>\n");
 657         fiq_debugger_printf(state,
 658                                 " ps            Process list\n"
 659                                 " sysrq         sysrq options\n"
 660                                 " sysrq <param> Execute sysrq with <param>\n");
 661 #ifdef CONFIG_KGDB
 662         fiq_debugger_printf(state,
 663                                 " kgdb          Enter kernel debugger\n");
 664 #endif
 665 }
 666
 667 static void fiq_debugger_take_affinity(void *info)
 668 {
 669         struct fiq_debugger_state *state = info;
 670         struct cpumask cpumask;
 671
 672         cpumask_clear(&cpumask);
 673         cpumask_set_cpu(get_cpu(), &cpumask);
 674
 675         irq_set_affinity(state->uart_irq, &cpumask);
 676 }
 677
 678 static void fiq_debugger_switch_cpu(struct fiq_debugger_state *state, int cpu)
 679 {
 680         if (!fiq_debugger_have_fiq(state))
 681                 smp_call_function_single(cpu, fiq_debugger_take_affinity, state,
 682                                 false);
 683         state->current_cpu = cpu;
 684 }
 685
 686 static bool fiq_debugger_fiq_exec(struct fiq_debugger_state *state,
 687                         const char *cmd, const struct pt_regs *regs,
 688                         void *svc_sp)
 689 {
 690         bool signal_helper = false;
 691
 692         if (!strcmp(cmd, "help") || !strcmp(cmd, "?")) {
 693                 fiq_debugger_help(state);
 694         } else if (!strcmp(cmd, "pc")) {
 695                 fiq_debugger_printf(state, " pc %08x cpsr %08x mode %s\n",
 696                         regs->ARM_pc, regs->ARM_cpsr,
 697                         mode_name(regs->ARM_cpsr));
 698         } else if (!strcmp(cmd, "regs")) {
 699                 fiq_debugger_dump_regs(state, regs);
 700         } else if (!strcmp(cmd, "allregs")) {
 701                 fiq_debugger_dump_allregs(state, regs);
 702         } else if (!strcmp(cmd, "bt")) {
 703                 fiq_debugger_dump_stacktrace(state, regs, 100, svc_sp);
 704         } else if (!strncmp(cmd, "reset", 5)) {
 705                 cmd += 5;
 706                 while (*cmd == ' ')
 707                         cmd++;
 708                 if (*cmd) {
 709                         char tmp_cmd[32];
 710                         strlcpy(tmp_cmd, cmd, sizeof(tmp_cmd));
 711                         machine_restart(tmp_cmd);
 712                 } else {
 713                         machine_restart(NULL);
 714                 }
 715         } else if (!strcmp(cmd, "irqs")) {
 716                 fiq_debugger_dump_irqs(state);
 717         } else if (!strcmp(cmd, "kmsg")) {
 718                 fiq_debugger_dump_kernel_log(state);
 719         } else if (!strcmp(cmd, "version")) {
 720                 fiq_debugger_printf(state, "%s\n", linux_banner);
 721         } else if (!strcmp(cmd, "sleep")) {
 722                 state->no_sleep = false;
 723                 fiq_debugger_printf(state, "enabling sleep\n");
 724         } else if (!strcmp(cmd, "nosleep")) {
 725                 state->no_sleep = true;
 726                 fiq_debugger_printf(state, "disabling sleep\n");
 727         } else if (!strcmp(cmd, "console")) {
 728                 fiq_debugger_printf(state, "console mode\n");
 729                 fiq_debugger_uart_flush(state);
 730                 state->console_enable = true;
 731         } else if (!strcmp(cmd, "cpu")) {
 732                 fiq_debugger_printf(state, "cpu %d\n", state->current_cpu);
 733         } else if (!strncmp(cmd, "cpu ", 4)) {
 734                 unsigned long cpu = 0;
 735                 if (strict_strtoul(cmd + 4, 10, &cpu) == 0)
 736                         fiq_debugger_switch_cpu(state, cpu);
 737                 else
 738                         fiq_debugger_printf(state, "invalid cpu\n");
 739                 fiq_debugger_printf(state, "cpu %d\n", state->current_cpu);
 740         } else {
 741                 if (state->debug_busy) {
 742                         fiq_debugger_printf(state,
 743                                 "command processor busy. trying to abort.\n");
 744                         state->debug_abort = -1;
 745                 } else {
 746                         strcpy(state->debug_cmd, cmd);
 747                         state->debug_busy = 1;
 748                 }
 749
 750                 return true;
 751         }
 752         if (!state->console_enable)
 753                 fiq_debugger_prompt(state);
 754
 755         return signal_helper;
 756 }
 757
 758 static void fiq_debugger_sleep_timer_expired(unsigned long data)
 759 {
 760         struct fiq_debugger_state *state = (struct fiq_debugger_state *)data;
 761         unsigned long flags;
 762
 763         spin_lock_irqsave(&state->sleep_timer_lock, flags);
 764         if (state->uart_enabled && !state->no_sleep) {
 765                 if (state->debug_enable && !state->console_enable) {
 766                         state->debug_enable = false;
 767                         fiq_debugger_printf_nfiq(state,
 768                                         "suspending fiq debugger\n");
 769                 }
 770                 state->ignore_next_wakeup_irq = true;
 771                 fiq_debugger_uart_disable(state);
 772                 state->uart_enabled = false;
 773                 fiq_debugger_enable_wakeup_irq(state);
 774         }
 775         wake_unlock(&state->debugger_wake_lock);
 776         spin_unlock_irqrestore(&state->sleep_timer_lock, flags);
 777 }
 778
 779 static void fiq_debugger_handle_wakeup(struct fiq_debugger_state *state)
 780 {
 781         unsigned long flags;
 782
 783         spin_lock_irqsave(&state->sleep_timer_lock, flags);
 784         if (state->wakeup_irq >= 0 && state->ignore_next_wakeup_irq) {
 785                 state->ignore_next_wakeup_irq = false;
 786         } else if (!state->uart_enabled) {
 787                 wake_lock(&state->debugger_wake_lock);
 788                 fiq_debugger_uart_enable(state);
 789                 state->uart_enabled = true;
 790                 fiq_debugger_disable_wakeup_irq(state);
 791                 mod_timer(&state->sleep_timer, jiffies + HZ / 2);
 792         }
 793         spin_unlock_irqrestore(&state->sleep_timer_lock, flags);
 794 }
 795
 796 static irqreturn_t fiq_debugger_wakeup_irq_handler(int irq, void *dev)
 797 {
 798         struct fiq_debugger_state *state = dev;
 799
 800         if (!state->no_sleep)
 801                 fiq_debugger_puts(state, "WAKEUP\n");
 802         fiq_debugger_handle_wakeup(state);
 803
 804         return IRQ_HANDLED;
 805 }
 806
 807 static
 808 void fiq_debugger_handle_console_irq_context(struct fiq_debugger_state *state)
 809 {
 810 #if defined(CONFIG_FIQ_DEBUGGER_CONSOLE)
 811         if (state->tty_port.ops) {
 812                 int i;
 813                 int count = fiq_debugger_ringbuf_level(state->tty_rbuf);
 814                 for (i = 0; i < count; i++) {
 815                         int c = fiq_debugger_ringbuf_peek(state->tty_rbuf, 0);
 816                         tty_insert_flip_char(&state->tty_port, c, TTY_NORMAL);
 817                         if (!fiq_debugger_ringbuf_consume(state->tty_rbuf, 1))
 818                                 pr_warn("fiq tty failed to consume byte\n");
 819                 }
 820                 tty_flip_buffer_push(&state->tty_port);
 821         }
 822 #endif
 823 }
 824
 825 static void fiq_debugger_handle_irq_context(struct fiq_debugger_state *state)
 826 {
 827         if (!state->no_sleep) {
 828                 unsigned long flags;
 829
 830                 spin_lock_irqsave(&state->sleep_timer_lock, flags);
 831                 wake_lock(&state->debugger_wake_lock);
 832                 mod_timer(&state->sleep_timer, jiffies + HZ * 5);
 833                 spin_unlock_irqrestore(&state->sleep_timer_lock, flags);
 834         }
 835         fiq_debugger_handle_console_irq_context(state);
 836         if (state->debug_busy) {
 837                 fiq_debugger_irq_exec(state, state->debug_cmd);
 838                 if (!state->console_enable)
 839                         fiq_debugger_prompt(state);
 840                 state->debug_busy = 0;
 841         }
 842 }
 843
 844 static int fiq_debugger_getc(struct fiq_debugger_state *state)
 845 {
 846         return state->pdata->uart_getc(state->pdev);
 847 }
 848
 849 static bool fiq_debugger_handle_uart_interrupt(struct fiq_debugger_state *state,
 850                         int this_cpu, const struct pt_regs *regs, void *svc_sp)
 851 {
 852         int c;
 853         static int last_c;
 854         int count = 0;
 855         bool signal_helper = false;
 856
 857         if (this_cpu != state->current_cpu) {
 858                 if (state->in_fiq)
 859                         return false;
 860
 861                 if (atomic_inc_return(&state->unhandled_fiq_count) !=
 862                                         MAX_UNHANDLED_FIQ_COUNT)
 863                         return false;
 864
 865                 fiq_debugger_printf(state,
 866                         "fiq_debugger: cpu %d not responding, "
 867                         "reverting to cpu %d\n", state->current_cpu,
 868                         this_cpu);
 869
 870                 atomic_set(&state->unhandled_fiq_count, 0);
 871                 fiq_debugger_switch_cpu(state, this_cpu);
 872                 return false;
 873         }
 874
 875         state->in_fiq = true;
 876
 877         while ((c = fiq_debugger_getc(state)) != FIQ_DEBUGGER_NO_CHAR) {
 878                 count++;
 879                 if (!state->debug_enable) {
 880                         if ((c == 13) || (c == 10)) {
 881                                 state->debug_enable = true;
 882                                 state->debug_count = 0;
 883                                 fiq_debugger_prompt(state);
 884                         }
 885                 } else if (c == FIQ_DEBUGGER_BREAK) {
 886                         state->console_enable = false;
 887                         fiq_debugger_puts(state, "fiq debugger mode\n");
 888                         state->debug_count = 0;
 889                         fiq_debugger_prompt(state);
 890 #ifdef CONFIG_FIQ_DEBUGGER_CONSOLE
 891                 } else if (state->console_enable && state->tty_rbuf) {
 892                         fiq_debugger_ringbuf_push(state->tty_rbuf, c);
 893                         signal_helper = true;
 894 #endif
 895                 } else if ((c >= ' ') && (c < 127)) {
 896                         if (state->debug_count < (DEBUG_MAX - 1)) {
 897                                 state->debug_buf[state->debug_count++] = c;
 898                                 fiq_debugger_putc(state, c);
 899                         }
 900                 } else if ((c == 8) || (c == 127)) {
 901                         if (state->debug_count > 0) {
 902                                 state->debug_count--;
 903                                 fiq_debugger_putc(state, 8);
 904                                 fiq_debugger_putc(state, ' ');
 905                                 fiq_debugger_putc(state, 8);
 906                         }
 907                 } else if ((c == 13) || (c == 10)) {
 908                         if (c == '\r' || (c == '\n' && last_c != '\r')) {
 909                                 fiq_debugger_putc(state, '\r');
 910                                 fiq_debugger_putc(state, '\n');
 911                         }
 912                         if (state->debug_count) {
 913                                 state->debug_buf[state->debug_count] = 0;
 914                                 state->debug_count = 0;
 915                                 signal_helper |=
 916                                         fiq_debugger_fiq_exec(state,
 917                                                         state->debug_buf,
 918                                                         regs, svc_sp);
 919                         } else {
 920                                 fiq_debugger_prompt(state);
 921                         }
 922                 }
 923                 last_c = c;
 924         }
 925         if (!state->console_enable)
 926                 fiq_debugger_uart_flush(state);
 927         if (state->pdata->fiq_ack)
 928                 state->pdata->fiq_ack(state->pdev, state->fiq);
 929
 930         /* poke sleep timer if necessary */
 931         if (state->debug_enable && !state->no_sleep)
 932                 signal_helper = true;
 933
 934         atomic_set(&state->unhandled_fiq_count, 0);
 935         state->in_fiq = false;
 936
 937         return signal_helper;
 938 }
 939
 940 #ifdef CONFIG_FIQ_GLUE
 941 static void fiq_debugger_fiq(struct fiq_glue_handler *h,
 942                 const struct pt_regs *regs, void *svc_sp)
 943 {
 944         struct fiq_debugger_state *state =
 945                 container_of(h, struct fiq_debugger_state, handler);
 946         unsigned int this_cpu = THREAD_INFO(svc_sp)->cpu;
 947         bool need_irq;
 948
 949         need_irq = fiq_debugger_handle_uart_interrupt(state, this_cpu, regs,
 950                         svc_sp);
 951         if (need_irq)
 952                 fiq_debugger_force_irq(state);
 953 }
 954 #endif
 955
 956 /*
 957  * When not using FIQs, we only use this single interrupt as an entry point.
 958  * This just effectively takes over the UART interrupt and does all the work
 959  * in this context.
 960  */
 961 static irqreturn_t fiq_debugger_uart_irq(int irq, void *dev)
 962 {
 963         struct fiq_debugger_state *state = dev;
 964         bool not_done;
 965
 966         fiq_debugger_handle_wakeup(state);
 967
 968         /* handle the debugger irq in regular context */
 969         not_done = fiq_debugger_handle_uart_interrupt(state, smp_processor_id(),
 970                                               get_irq_regs(),
 971                                               current_thread_info());
 972         if (not_done)
 973                 fiq_debugger_handle_irq_context(state);
 974
 975         return IRQ_HANDLED;
 976 }
 977
 978 /*
 979  * If FIQs are used, not everything can happen in fiq context.
 980  * FIQ handler does what it can and then signals this interrupt to finish the
 981  * job in irq context.
 982  */
 983 static irqreturn_t fiq_debugger_signal_irq(int irq, void *dev)
 984 {
 985         struct fiq_debugger_state *state = dev;
 986
 987         if (state->pdata->force_irq_ack)
 988                 state->pdata->force_irq_ack(state->pdev, state->signal_irq);
 989
 990         fiq_debugger_handle_irq_context(state);
 991
 992         return IRQ_HANDLED;
 993 }
 994
 995 #ifdef CONFIG_FIQ_GLUE
 996 static void fiq_debugger_resume(struct fiq_glue_handler *h)
 997 {
 998         struct fiq_debugger_state *state =
 999                 container_of(h, struct fiq_debugger_state, handler);
1000         if (state->pdata->uart_resume)
1001                 state->pdata->uart_resume(state->pdev);
1002 }
1003 #endif
1004
1005 #if defined(CONFIG_FIQ_DEBUGGER_CONSOLE)
1006 struct tty_driver *fiq_debugger_console_device(struct console *co, int *index)
1007 {
1008         *index = co->index;
1009         return fiq_tty_driver;
1010 }
1011
1012 static void fiq_debugger_console_write(struct console *co,
1013                                 const char *s, unsigned int count)
1014 {
1015         struct fiq_debugger_state *state;
1016         unsigned long flags;
1017
1018         state = container_of(co, struct fiq_debugger_state, console);
1019
1020         if (!state->console_enable && !state->syslog_dumping)
1021                 return;
1022
1023         fiq_debugger_uart_enable(state);
1024         spin_lock_irqsave(&state->console_lock, flags);
1025         while (count--) {
1026                 if (*s == '\n')
1027                         fiq_debugger_putc(state, '\r');
1028                 fiq_debugger_putc(state, *s++);
1029         }
1030         fiq_debugger_uart_flush(state);
1031         spin_unlock_irqrestore(&state->console_lock, flags);
1032         fiq_debugger_uart_disable(state);
1033 }
1034
1035 static struct console fiq_debugger_console = {
1036         .name = "ttyFIQ",
1037         .device = fiq_debugger_console_device,
1038         .write = fiq_debugger_console_write,
1039         .flags = CON_PRINTBUFFER | CON_ANYTIME | CON_ENABLED,
1040 };
1041
1042 int fiq_tty_open(struct tty_struct *tty, struct file *filp)
1043 {
1044         int line = tty->index;
1045         struct fiq_debugger_state **states = tty->driver->driver_state;
1046         struct fiq_debugger_state *state = states[line];
1047
1048         return tty_port_open(&state->tty_port, tty, filp);
1049 }
1050
1051 void fiq_tty_close(struct tty_struct *tty, struct file *filp)
1052 {
1053         tty_port_close(tty->port, tty, filp);
1054 }
1055
1056 int  fiq_tty_write(struct tty_struct *tty, const unsigned char *buf, int count)
1057 {
1058         int i;
1059         int line = tty->index;
1060         struct fiq_debugger_state **states = tty->driver->driver_state;
1061         struct fiq_debugger_state *state = states[line];
1062
1063         if (!state->console_enable)
1064                 return count;
1065
1066         fiq_debugger_uart_enable(state);
1067         spin_lock_irq(&state->console_lock);
1068         for (i = 0; i < count; i++)
1069                 fiq_debugger_putc(state, *buf++);
1070         spin_unlock_irq(&state->console_lock);
1071         fiq_debugger_uart_disable(state);
1072
1073         return count;
1074 }
1075
1076 int  fiq_tty_write_room(struct tty_struct *tty)
1077 {
1078         return 16;
1079 }
1080
1081 #ifdef CONFIG_CONSOLE_POLL
1082 static int fiq_tty_poll_init(struct tty_driver *driver, int line, char *options)
1083 {
1084         return 0;
1085 }
1086
1087 static int fiq_tty_poll_get_char(struct tty_driver *driver, int line)
1088 {
1089         struct fiq_debugger_state **states = driver->driver_state;
1090         struct fiq_debugger_state *state = states[line];
1091         int c = NO_POLL_CHAR;
1092
1093         fiq_debugger_uart_enable(state);
1094         if (fiq_debugger_have_fiq(state)) {
1095                 int count = fiq_debugger_ringbuf_level(state->tty_rbuf);
1096                 if (count > 0) {
1097                         c = fiq_debugger_ringbuf_peek(state->tty_rbuf, 0);
1098                         fiq_debugger_ringbuf_consume(state->tty_rbuf, 1);
1099                 }
1100         } else {
1101                 c = fiq_debugger_getc(state);
1102                 if (c == FIQ_DEBUGGER_NO_CHAR)
1103                         c = NO_POLL_CHAR;
1104         }
1105         fiq_debugger_uart_disable(state);
1106
1107         return c;
1108 }
1109
1110 static void fiq_tty_poll_put_char(struct tty_driver *driver, int line, char ch)
1111 {
1112         struct fiq_debugger_state **states = driver->driver_state;
1113         struct fiq_debugger_state *state = states[line];
1114         fiq_debugger_uart_enable(state);
1115         fiq_debugger_putc(state, ch);
1116         fiq_debugger_uart_disable(state);
1117 }
1118 #endif
1119
1120 static const struct tty_port_operations fiq_tty_port_ops;
1121
1122 static const struct tty_operations fiq_tty_driver_ops = {
1123         .write = fiq_tty_write,
1124         .write_room = fiq_tty_write_room,
1125         .open = fiq_tty_open,
1126         .close = fiq_tty_close,
1127 #ifdef CONFIG_CONSOLE_POLL
1128         .poll_init = fiq_tty_poll_init,
1129         .poll_get_char = fiq_tty_poll_get_char,
1130         .poll_put_char = fiq_tty_poll_put_char,
1131 #endif
1132 };
1133
1134 static int fiq_debugger_tty_init(void)
1135 {
1136         int ret;
1137         struct fiq_debugger_state **states = NULL;
1138
1139         states = kzalloc(sizeof(*states) * MAX_FIQ_DEBUGGER_PORTS, GFP_KERNEL);
1140         if (!states) {
1141                 pr_err("Failed to allocate fiq debugger state structres\n");
1142                 return -ENOMEM;
1143         }
1144
1145         fiq_tty_driver = alloc_tty_driver(MAX_FIQ_DEBUGGER_PORTS);
1146         if (!fiq_tty_driver) {
1147                 pr_err("Failed to allocate fiq debugger tty\n");
1148                 ret = -ENOMEM;
1149                 goto err_free_state;
1150         }
1151
1152         fiq_tty_driver->owner           = THIS_MODULE;
1153         fiq_tty_driver->driver_name     = "fiq-debugger";
1154         fiq_tty_driver->name            = "ttyFIQ";
1155         fiq_tty_driver->type            = TTY_DRIVER_TYPE_SERIAL;
1156         fiq_tty_driver->subtype         = SERIAL_TYPE_NORMAL;
1157         fiq_tty_driver->init_termios    = tty_std_termios;
1158         fiq_tty_driver->flags           = TTY_DRIVER_REAL_RAW |
1159                                           TTY_DRIVER_DYNAMIC_DEV;
1160         fiq_tty_driver->driver_state    = states;
1161
1162         fiq_tty_driver->init_termios.c_cflag =
1163                                         B115200 | CS8 | CREAD | HUPCL | CLOCAL;
1164         fiq_tty_driver->init_termios.c_ispeed = 115200;
1165         fiq_tty_driver->init_termios.c_ospeed = 115200;
1166
1167         tty_set_operations(fiq_tty_driver, &fiq_tty_driver_ops);
1168
1169         ret = tty_register_driver(fiq_tty_driver);
1170         if (ret) {
1171                 pr_err("Failed to register fiq tty: %d\n", ret);
1172                 goto err_free_tty;
1173         }
1174
1175         pr_info("Registered FIQ tty driver\n");
1176         return 0;
1177
1178 err_free_tty:
1179         put_tty_driver(fiq_tty_driver);
1180         fiq_tty_driver = NULL;
1181 err_free_state:
1182         kfree(states);
1183         return ret;
1184 }
1185
1186 static int fiq_debugger_tty_init_one(struct fiq_debugger_state *state)
1187 {
1188         int ret;
1189         struct device *tty_dev;
1190         struct fiq_debugger_state **states = fiq_tty_driver->driver_state;
1191
1192         states[state->pdev->id] = state;
1193
1194         state->tty_rbuf = fiq_debugger_ringbuf_alloc(1024);
1195         if (!state->tty_rbuf) {
1196                 pr_err("Failed to allocate fiq debugger ringbuf\n");
1197                 ret = -ENOMEM;
1198                 goto err;
1199         }
1200
1201         tty_port_init(&state->tty_port);
1202         state->tty_port.ops = &fiq_tty_port_ops;
1203
1204         tty_dev = tty_port_register_device(&state->tty_port, fiq_tty_driver,
1205                                            state->pdev->id, &state->pdev->dev);
1206         if (IS_ERR(tty_dev)) {
1207                 pr_err("Failed to register fiq debugger tty device\n");
1208                 ret = PTR_ERR(tty_dev);
1209                 goto err;
1210         }
1211
1212         device_set_wakeup_capable(tty_dev, 1);
1213
1214         pr_info("Registered fiq debugger ttyFIQ%d\n", state->pdev->id);
1215
1216         return 0;
1217
1218 err:
1219         fiq_debugger_ringbuf_free(state->tty_rbuf);
1220         state->tty_rbuf = NULL;
1221         return ret;
1222 }
1223 #endif
1224
1225 static int fiq_debugger_dev_suspend(struct device *dev)
1226 {
1227         struct platform_device *pdev = to_platform_device(dev);
1228         struct fiq_debugger_state *state = platform_get_drvdata(pdev);
1229
1230         if (state->pdata->uart_dev_suspend)
1231                 return state->pdata->uart_dev_suspend(pdev);
1232         return 0;
1233 }
1234
1235 static int fiq_debugger_dev_resume(struct device *dev)
1236 {
1237         struct platform_device *pdev = to_platform_device(dev);
1238         struct fiq_debugger_state *state = platform_get_drvdata(pdev);
1239
1240         if (state->pdata->uart_dev_resume)
1241                 return state->pdata->uart_dev_resume(pdev);
1242         return 0;
1243 }
1244
1245 static int fiq_debugger_probe(struct platform_device *pdev)
1246 {
1247         int ret;
1248         struct fiq_debugger_pdata *pdata = dev_get_platdata(&pdev->dev);
1249         struct fiq_debugger_state *state;
1250         int fiq;
1251         int uart_irq;
1252
1253         if (pdev->id >= MAX_FIQ_DEBUGGER_PORTS)
1254                 return -EINVAL;
1255
1256         if (!pdata->uart_getc || !pdata->uart_putc)
1257                 return -EINVAL;
1258         if ((pdata->uart_enable && !pdata->uart_disable) ||
1259             (!pdata->uart_enable && pdata->uart_disable))
1260                 return -EINVAL;
1261
1262         fiq = platform_get_irq_byname(pdev, "fiq");
1263         uart_irq = platform_get_irq_byname(pdev, "uart_irq");
1264
1265         /* uart_irq mode and fiq mode are mutually exclusive, but one of them
1266          * is required */
1267         if ((uart_irq < 0 && fiq < 0) || (uart_irq >= 0 && fiq >= 0))
1268                 return -EINVAL;
1269         if (fiq >= 0 && !pdata->fiq_enable)
1270                 return -EINVAL;
1271
1272         state = kzalloc(sizeof(*state), GFP_KERNEL);
1273         setup_timer(&state->sleep_timer, fiq_debugger_sleep_timer_expired,
1274                     (unsigned long)state);
1275         state->pdata = pdata;
1276         state->pdev = pdev;
1277         state->no_sleep = initial_no_sleep;
1278         state->debug_enable = initial_debug_enable;
1279         state->console_enable = initial_console_enable;
1280
1281         state->fiq = fiq;
1282         state->uart_irq = uart_irq;
1283         state->signal_irq = platform_get_irq_byname(pdev, "signal");
1284         state->wakeup_irq = platform_get_irq_byname(pdev, "wakeup");
1285
1286         INIT_WORK(&state->work, fiq_debugger_work);
1287         spin_lock_init(&state->work_lock);
1288
1289         platform_set_drvdata(pdev, state);
1290
1291         spin_lock_init(&state->sleep_timer_lock);
1292
1293         if (state->wakeup_irq < 0 && fiq_debugger_have_fiq(state))
1294                 state->no_sleep = true;
1295         state->ignore_next_wakeup_irq = !state->no_sleep;
1296
1297         wake_lock_init(&state->debugger_wake_lock,
1298                         WAKE_LOCK_SUSPEND, "serial-debug");
1299
1300         state->clk = clk_get(&pdev->dev, NULL);
1301         if (IS_ERR(state->clk))
1302                 state->clk = NULL;
1303
1304         /* do not call pdata->uart_enable here since uart_init may still
1305          * need to do some initialization before uart_enable can work.
1306          * So, only try to manage the clock during init.
1307          */
1308         if (state->clk)
1309                 clk_enable(state->clk);
1310
1311         if (pdata->uart_init) {
1312                 ret = pdata->uart_init(pdev);
1313                 if (ret)
1314                         goto err_uart_init;
1315         }
1316
1317         fiq_debugger_printf_nfiq(state,
1318                                 "<hit enter %sto activate fiq debugger>\n",
1319                                 state->no_sleep ? "" : "twice ");
1320
1321 #ifdef CONFIG_FIQ_GLUE
1322         if (fiq_debugger_have_fiq(state)) {
1323                 state->handler.fiq = fiq_debugger_fiq;
1324                 state->handler.resume = fiq_debugger_resume;
1325                 ret = fiq_glue_register_handler(&state->handler);
1326                 if (ret) {
1327                         pr_err("%s: could not install fiq handler\n", __func__);
1328                         goto err_register_irq;
1329                 }
1330
1331                 pdata->fiq_enable(pdev, state->fiq, 1);
1332         } else
1333 #endif
1334         {
1335                 ret = request_irq(state->uart_irq, fiq_debugger_uart_irq,
1336                                   IRQF_NO_SUSPEND, "debug", state);
1337                 if (ret) {
1338                         pr_err("%s: could not install irq handler\n", __func__);
1339                         goto err_register_irq;
1340                 }
1341
1342                 /* for irq-only mode, we want this irq to wake us up, if it
1343                  * can.
1344                  */
1345                 enable_irq_wake(state->uart_irq);
1346         }
1347
1348         if (state->clk)
1349                 clk_disable(state->clk);
1350
1351         if (state->signal_irq >= 0) {
1352                 ret = request_irq(state->signal_irq, fiq_debugger_signal_irq,
1353                           IRQF_TRIGGER_RISING, "debug-signal", state);
1354                 if (ret)
1355                         pr_err("serial_debugger: could not install signal_irq");
1356         }
1357
1358         if (state->wakeup_irq >= 0) {
1359                 ret = request_irq(state->wakeup_irq,
1360                                   fiq_debugger_wakeup_irq_handler,
1361                                   IRQF_TRIGGER_FALLING | IRQF_DISABLED,
1362                                   "debug-wakeup", state);
1363                 if (ret) {
1364                         pr_err("serial_debugger: "
1365                                 "could not install wakeup irq\n");
1366                         state->wakeup_irq = -1;
1367                 } else {
1368                         ret = enable_irq_wake(state->wakeup_irq);
1369                         if (ret) {
1370                                 pr_err("serial_debugger: "
1371                                         "could not enable wakeup\n");
1372                                 state->wakeup_irq_no_set_wake = true;
1373                         }
1374                 }
1375         }
1376         if (state->no_sleep)
1377                 fiq_debugger_handle_wakeup(state);
1378
1379 #if defined(CONFIG_FIQ_DEBUGGER_CONSOLE)
1380         spin_lock_init(&state->console_lock);
1381         state->console = fiq_debugger_console;
1382         state->console.index = pdev->id;
1383         if (!console_set_on_cmdline)
1384                 add_preferred_console(state->console.name,
1385                         state->console.index, NULL);
1386         register_console(&state->console);
1387         fiq_debugger_tty_init_one(state);
1388 #endif
1389         return 0;
1390
1391 err_register_irq:
1392         if (pdata->uart_free)
1393                 pdata->uart_free(pdev);
1394 err_uart_init:
1395         if (state->clk)
1396                 clk_disable(state->clk);
1397         if (state->clk)
1398                 clk_put(state->clk);
1399         wake_lock_destroy(&state->debugger_wake_lock);
1400         platform_set_drvdata(pdev, NULL);
1401         kfree(state);
1402         return ret;
1403 }
1404
1405 static const struct dev_pm_ops fiq_debugger_dev_pm_ops = {
1406         .suspend        = fiq_debugger_dev_suspend,
1407         .resume         = fiq_debugger_dev_resume,
1408 };
1409
1410 static struct platform_driver fiq_debugger_driver = {
1411         .probe  = fiq_debugger_probe,
1412         .driver = {
1413                 .name   = "fiq_debugger",
1414                 .pm     = &fiq_debugger_dev_pm_ops,
1415         },
1416 };
1417
1418 static int __init fiq_debugger_init(void)
1419 {
1420 #if defined(CONFIG_FIQ_DEBUGGER_CONSOLE)
1421         fiq_debugger_tty_init();
1422 #endif
1423         return platform_driver_register(&fiq_debugger_driver);
1424 }
1425
1426 postcore_initcall(fiq_debugger_init);