arch/arm/common/fiq_debugger.c

   1 /*
   2  * arch/arm/common/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_debugger.h>
  26 #include <linux/kernel_stat.h>
  27 #include <linux/irq.h>
  28 #include <linux/delay.h>
  29 #include <linux/sched.h>
  30 #include <linux/slab.h>
  31 #include <linux/timer.h>
  32 #include <linux/tty.h>
  33 #include <linux/tty_flip.h>
  34 #include <linux/wakelock.h>
  35
  36 #include <asm/fiq_debugger.h>
  37 #include <asm/fiq_glue.h>
  38 #include <asm/stacktrace.h>
  39
  40 #include <mach/system.h>
  41
  42 #include <linux/uaccess.h>
  43
  44 #include "fiq_debugger_ringbuf.h"
  45
  46 #define DEBUG_MAX 64
  47
  48 struct fiq_debugger_state {
  49         struct fiq_glue_handler handler;
  50
  51         int fiq;
  52         int signal_irq;
  53         int wakeup_irq;
  54         bool wakeup_irq_no_set_wake;
  55         struct clk *clk;
  56         struct fiq_debugger_pdata *pdata;
  57         struct platform_device *pdev;
  58
  59         char debug_cmd[DEBUG_MAX];
  60         int debug_busy;
  61         int debug_abort;
  62
  63         char debug_buf[DEBUG_MAX];
  64         int debug_count;
  65
  66         bool no_sleep;
  67         bool debug_enable;
  68         bool ignore_next_wakeup_irq;
  69         struct timer_list sleep_timer;
  70         bool uart_clk_enabled;
  71         struct wake_lock debugger_wake_lock;
  72         bool console_enable;
  73
  74 #ifdef CONFIG_FIQ_DEBUGGER_CONSOLE
  75         struct console console;
  76         struct tty_driver *tty_driver;
  77         struct tty_struct *tty;
  78         int tty_open_count;
  79         struct fiq_debugger_ringbuf *tty_rbuf;
  80 #endif
  81
  82         unsigned int last_irqs[NR_IRQS];
  83 };
  84
  85 #ifdef CONFIG_FIQ_DEBUGGER_NO_SLEEP
  86 static bool initial_no_sleep = true;
  87 #else
  88 static bool initial_no_sleep;
  89 #endif
  90 static bool initial_debug_enable;
  91 static bool initial_console_enable;
  92
  93 module_param_named(no_sleep, initial_no_sleep, bool, 0644);
  94 module_param_named(debug_enable, initial_debug_enable, bool, 0644);
  95 module_param_named(console_enable, initial_console_enable, bool, 0644);
  96
  97 #ifdef CONFIG_FIQ_DEBUGGER_WAKEUP_IRQ_ALWAYS_ON
  98 static inline void enable_wakeup_irq(struct fiq_debugger_state *state) {}
  99 static inline void disable_wakeup_irq(struct fiq_debugger_state *state) {}
 100 #else
 101 static inline void enable_wakeup_irq(struct fiq_debugger_state *state)
 102 {
 103         if (state->wakeup_irq < 0)
 104                 return;
 105         enable_irq(state->wakeup_irq);
 106         if (!state->wakeup_irq_no_set_wake)
 107                 enable_irq_wake(state->wakeup_irq);
 108 }
 109 static inline void disable_wakeup_irq(struct fiq_debugger_state *state)
 110 {
 111         if (state->wakeup_irq < 0)
 112                 return;
 113         disable_irq_nosync(state->wakeup_irq);
 114         if (!state->wakeup_irq_no_set_wake)
 115                 disable_irq_wake(state->wakeup_irq);
 116 }
 117 #endif
 118
 119 static void debug_force_irq(struct fiq_debugger_state *state)
 120 {
 121         unsigned int irq = state->signal_irq;
 122         if (state->pdata->force_irq)
 123                 state->pdata->force_irq(state->pdev, irq);
 124         else {
 125                 struct irq_chip *chip = get_irq_chip(irq);
 126                 if (chip && chip->retrigger)
 127                         chip->retrigger(irq);
 128         }
 129 }
 130
 131 static void debug_uart_flush(struct fiq_debugger_state *state)
 132 {
 133         if (state->pdata->uart_flush)
 134                 state->pdata->uart_flush(state->pdev);
 135 }
 136
 137 static void debug_puts(struct fiq_debugger_state *state, char *s)
 138 {
 139         unsigned c;
 140         while ((c = *s++)) {
 141                 if (c == '\n')
 142                         state->pdata->uart_putc(state->pdev, '\r');
 143                 state->pdata->uart_putc(state->pdev, c);
 144         }
 145 }
 146
 147 static void debug_prompt(struct fiq_debugger_state *state)
 148 {
 149         debug_puts(state, "debug> ");
 150 }
 151
 152 int log_buf_copy(char *dest, int idx, int len);
 153 static void dump_kernel_log(struct fiq_debugger_state *state)
 154 {
 155         char buf[1024];
 156         int idx = 0;
 157         int ret;
 158         int saved_oip;
 159
 160         /* setting oops_in_progress prevents log_buf_copy()
 161          * from trying to take a spinlock which will make it
 162          * very unhappy in some cases...
 163          */
 164         saved_oip = oops_in_progress;
 165         oops_in_progress = 1;
 166         for (;;) {
 167                 ret = log_buf_copy(buf, idx, 1023);
 168                 if (ret <= 0)
 169                         break;
 170                 buf[ret] = 0;
 171                 debug_puts(state, buf);
 172                 idx += ret;
 173         }
 174         oops_in_progress = saved_oip;
 175 }
 176
 177 static char *mode_name(unsigned cpsr)
 178 {
 179         switch (cpsr & MODE_MASK) {
 180         case USR_MODE: return "USR";
 181         case FIQ_MODE: return "FIQ";
 182         case IRQ_MODE: return "IRQ";
 183         case SVC_MODE: return "SVC";
 184         case ABT_MODE: return "ABT";
 185         case UND_MODE: return "UND";
 186         case SYSTEM_MODE: return "SYS";
 187         default: return "???";
 188         }
 189 }
 190
 191 static int debug_printf(void *cookie, const char *fmt, ...)
 192 {
 193         struct fiq_debugger_state *state = cookie;
 194         char buf[256];
 195         va_list ap;
 196
 197         va_start(ap, fmt);
 198         vsnprintf(buf, sizeof(buf), fmt, ap);
 199         va_end(ap);
 200
 201         debug_puts(state, buf);
 202         return state->debug_abort;
 203 }
 204
 205 /* Safe outside fiq context */
 206 static int debug_printf_nfiq(void *cookie, const char *fmt, ...)
 207 {
 208         struct fiq_debugger_state *state = cookie;
 209         char buf[256];
 210         va_list ap;
 211         unsigned long irq_flags;
 212
 213         va_start(ap, fmt);
 214         vsnprintf(buf, 128, fmt, ap);
 215         va_end(ap);
 216
 217         local_irq_save(irq_flags);
 218         debug_puts(state, buf);
 219         debug_uart_flush(state);
 220         local_irq_restore(irq_flags);
 221         return state->debug_abort;
 222 }
 223
 224 static void dump_regs(struct fiq_debugger_state *state, unsigned *regs)
 225 {
 226         debug_printf(state, " r0 %08x  r1 %08x  r2 %08x  r3 %08x\n",
 227                         regs[0], regs[1], regs[2], regs[3]);
 228         debug_printf(state, " r4 %08x  r5 %08x  r6 %08x  r7 %08x\n",
 229                         regs[4], regs[5], regs[6], regs[7]);
 230         debug_printf(state, " r8 %08x  r9 %08x r10 %08x r11 %08x  mode %s\n",
 231                         regs[8], regs[9], regs[10], regs[11],
 232                         mode_name(regs[16]));
 233         if ((regs[16] & MODE_MASK) == USR_MODE)
 234                 debug_printf(state, " ip %08x  sp %08x  lr %08x  pc %08x  "
 235                                 "cpsr %08x\n", regs[12], regs[13], regs[14],
 236                                 regs[15], regs[16]);
 237         else
 238                 debug_printf(state, " ip %08x  sp %08x  lr %08x  pc %08x  "
 239                                 "cpsr %08x  spsr %08x\n", regs[12], regs[13],
 240                                 regs[14], regs[15], regs[16], regs[17]);
 241 }
 242
 243 struct mode_regs {
 244         unsigned long sp_svc;
 245         unsigned long lr_svc;
 246         unsigned long spsr_svc;
 247
 248         unsigned long sp_abt;
 249         unsigned long lr_abt;
 250         unsigned long spsr_abt;
 251
 252         unsigned long sp_und;
 253         unsigned long lr_und;
 254         unsigned long spsr_und;
 255
 256         unsigned long sp_irq;
 257         unsigned long lr_irq;
 258         unsigned long spsr_irq;
 259
 260         unsigned long r8_fiq;
 261         unsigned long r9_fiq;
 262         unsigned long r10_fiq;
 263         unsigned long r11_fiq;
 264         unsigned long r12_fiq;
 265         unsigned long sp_fiq;
 266         unsigned long lr_fiq;
 267         unsigned long spsr_fiq;
 268 };
 269
 270 void __naked get_mode_regs(struct mode_regs *regs)
 271 {
 272         asm volatile (
 273         "mrs    r1, cpsr\n"
 274         "msr    cpsr_c, #0xd3 @(SVC_MODE | PSR_I_BIT | PSR_F_BIT)\n"
 275         "stmia  r0!, {r13 - r14}\n"
 276         "mrs    r2, spsr\n"
 277         "msr    cpsr_c, #0xd7 @(ABT_MODE | PSR_I_BIT | PSR_F_BIT)\n"
 278         "stmia  r0!, {r2, r13 - r14}\n"
 279         "mrs    r2, spsr\n"
 280         "msr    cpsr_c, #0xdb @(UND_MODE | PSR_I_BIT | PSR_F_BIT)\n"
 281         "stmia  r0!, {r2, r13 - r14}\n"
 282         "mrs    r2, spsr\n"
 283         "msr    cpsr_c, #0xd2 @(IRQ_MODE | PSR_I_BIT | PSR_F_BIT)\n"
 284         "stmia  r0!, {r2, r13 - r14}\n"
 285         "mrs    r2, spsr\n"
 286         "msr    cpsr_c, #0xd1 @(FIQ_MODE | PSR_I_BIT | PSR_F_BIT)\n"
 287         "stmia  r0!, {r2, r8 - r14}\n"
 288         "mrs    r2, spsr\n"
 289         "stmia  r0!, {r2}\n"
 290         "msr    cpsr_c, r1\n"
 291         "bx     lr\n");
 292 }
 293
 294
 295 static void dump_allregs(struct fiq_debugger_state *state, unsigned *regs)
 296 {
 297         struct mode_regs mode_regs;
 298         dump_regs(state, regs);
 299         get_mode_regs(&mode_regs);
 300         debug_printf(state, " svc: sp %08x  lr %08x  spsr %08x\n",
 301                         mode_regs.sp_svc, mode_regs.lr_svc, mode_regs.spsr_svc);
 302         debug_printf(state, " abt: sp %08x  lr %08x  spsr %08x\n",
 303                         mode_regs.sp_abt, mode_regs.lr_abt, mode_regs.spsr_abt);
 304         debug_printf(state, " und: sp %08x  lr %08x  spsr %08x\n",
 305                         mode_regs.sp_und, mode_regs.lr_und, mode_regs.spsr_und);
 306         debug_printf(state, " irq: sp %08x  lr %08x  spsr %08x\n",
 307                         mode_regs.sp_irq, mode_regs.lr_irq, mode_regs.spsr_irq);
 308         debug_printf(state, " fiq: r8 %08x  r9 %08x  r10 %08x  r11 %08x  "
 309                         "r12 %08x\n",
 310                         mode_regs.r8_fiq, mode_regs.r9_fiq, mode_regs.r10_fiq,
 311                         mode_regs.r11_fiq, mode_regs.r12_fiq);
 312         debug_printf(state, " fiq: sp %08x  lr %08x  spsr %08x\n",
 313                         mode_regs.sp_fiq, mode_regs.lr_fiq, mode_regs.spsr_fiq);
 314 }
 315
 316 static void dump_irqs(struct fiq_debugger_state *state)
 317 {
 318         int n;
 319         debug_printf(state, "irqnr       total  since-last   status  name\n");
 320         for (n = 0; n < NR_IRQS; n++) {
 321                 struct irqaction *act = irq_desc[n].action;
 322                 if (!act && !kstat_irqs(n))
 323                         continue;
 324                 debug_printf(state, "%5d: %10u %11u %8x  %s\n", n,
 325                         kstat_irqs(n),
 326                         kstat_irqs(n) - state->last_irqs[n],
 327                         irq_desc[n].status,
 328                         (act && act->name) ? act->name : "???");
 329                 state->last_irqs[n] = kstat_irqs(n);
 330         }
 331 }
 332
 333 struct stacktrace_state {
 334         struct fiq_debugger_state *state;
 335         unsigned int depth;
 336 };
 337
 338 static int report_trace(struct stackframe *frame, void *d)
 339 {
 340         struct stacktrace_state *sts = d;
 341
 342         if (sts->depth) {
 343                 debug_printf(sts->state,
 344                         "  pc: %p (%pF), lr %p (%pF), sp %p, fp %p\n",
 345                         frame->pc, frame->pc, frame->lr, frame->lr,
 346                         frame->sp, frame->fp);
 347                 sts->depth--;
 348                 return 0;
 349         }
 350         debug_printf(sts->state, "  ...\n");
 351
 352         return sts->depth == 0;
 353 }
 354
 355 struct frame_tail {
 356         struct frame_tail *fp;
 357         unsigned long sp;
 358         unsigned long lr;
 359 } __attribute__((packed));
 360
 361 static struct frame_tail *user_backtrace(struct fiq_debugger_state *state,
 362                                         struct frame_tail *tail)
 363 {
 364         struct frame_tail buftail[2];
 365
 366         /* Also check accessibility of one struct frame_tail beyond */
 367         if (!access_ok(VERIFY_READ, tail, sizeof(buftail))) {
 368                 debug_printf(state, "  invalid frame pointer %p\n", tail);
 369                 return NULL;
 370         }
 371         if (__copy_from_user_inatomic(buftail, tail, sizeof(buftail))) {
 372                 debug_printf(state,
 373                         "  failed to copy frame pointer %p\n", tail);
 374                 return NULL;
 375         }
 376
 377         debug_printf(state, "  %p\n", buftail[0].lr);
 378
 379         /* frame pointers should strictly progress back up the stack
 380          * (towards higher addresses) */
 381         if (tail >= buftail[0].fp)
 382                 return NULL;
 383
 384         return buftail[0].fp-1;
 385 }
 386
 387 void dump_stacktrace(struct fiq_debugger_state *state,
 388                 struct pt_regs * const regs, unsigned int depth, void *ssp)
 389 {
 390         struct frame_tail *tail;
 391         struct thread_info *real_thread_info = (struct thread_info *)
 392                                 ((unsigned long)ssp & ~(THREAD_SIZE - 1));
 393         struct stacktrace_state sts;
 394
 395         sts.depth = depth;
 396         sts.state = state;
 397         *current_thread_info() = *real_thread_info;
 398
 399         if (!current)
 400                 debug_printf(state, "current NULL\n");
 401         else
 402                 debug_printf(state, "pid: %d  comm: %s\n",
 403                         current->pid, current->comm);
 404         dump_regs(state, (unsigned *)regs);
 405
 406         if (!user_mode(regs)) {
 407                 struct stackframe frame;
 408                 frame.fp = regs->ARM_fp;
 409                 frame.sp = regs->ARM_sp;
 410                 frame.lr = regs->ARM_lr;
 411                 frame.pc = regs->ARM_pc;
 412                 debug_printf(state,
 413                         "  pc: %p (%pF), lr %p (%pF), sp %p, fp %p\n",
 414                         regs->ARM_pc, regs->ARM_pc, regs->ARM_lr, regs->ARM_lr,
 415                         regs->ARM_sp, regs->ARM_fp);
 416                 walk_stackframe(&frame, report_trace, &sts);
 417                 return;
 418         }
 419
 420         tail = ((struct frame_tail *) regs->ARM_fp) - 1;
 421         while (depth-- && tail && !((unsigned long) tail & 3))
 422                 tail = user_backtrace(state, tail);
 423 }
 424
 425 static void debug_exec(struct fiq_debugger_state *state,
 426                         const char *cmd, unsigned *regs, void *svc_sp)
 427 {
 428         if (!strcmp(cmd, "pc")) {
 429                 debug_printf(state, " pc %08x cpsr %08x mode %s\n",
 430                         regs[15], regs[16], mode_name(regs[16]));
 431         } else if (!strcmp(cmd, "regs")) {
 432                 dump_regs(state, regs);
 433         } else if (!strcmp(cmd, "allregs")) {
 434                 dump_allregs(state, regs);
 435         } else if (!strcmp(cmd, "bt")) {
 436                 dump_stacktrace(state, (struct pt_regs *)regs, 100, svc_sp);
 437         } else if (!strcmp(cmd, "reboot")) {
 438                 arch_reset(0, 0);
 439         } else if (!strcmp(cmd, "irqs")) {
 440                 dump_irqs(state);
 441         } else if (!strcmp(cmd, "kmsg")) {
 442                 dump_kernel_log(state);
 443         } else if (!strcmp(cmd, "version")) {
 444                 debug_printf(state, "%s\n", linux_banner);
 445         } else if (!strcmp(cmd, "sleep")) {
 446                 state->no_sleep = false;
 447         } else if (!strcmp(cmd, "nosleep")) {
 448                 state->no_sleep = true;
 449         } else if (!strcmp(cmd, "console")) {
 450                 state->console_enable = true;
 451                 debug_printf(state, "console mode\n");
 452         } else {
 453                 if (state->debug_busy) {
 454                         debug_printf(state,
 455                                 "command processor busy. trying to abort.\n");
 456                         state->debug_abort = -1;
 457                 } else {
 458                         strcpy(state->debug_cmd, cmd);
 459                         state->debug_busy = 1;
 460                 }
 461
 462                 debug_force_irq(state);
 463
 464                 return;
 465         }
 466         if (!state->console_enable)
 467                 debug_prompt(state);
 468 }
 469
 470 static void sleep_timer_expired(unsigned long data)
 471 {
 472         struct fiq_debugger_state *state = (struct fiq_debugger_state *)data;
 473
 474         if (state->uart_clk_enabled && !state->no_sleep) {
 475                 if (state->debug_enable) {
 476                         state->debug_enable = false;
 477                         debug_printf_nfiq(state, "suspending fiq debugger\n");
 478                 }
 479                 state->ignore_next_wakeup_irq = true;
 480                 if (state->clk)
 481                         clk_disable(state->clk);
 482                 state->uart_clk_enabled = false;
 483                 enable_wakeup_irq(state);
 484         }
 485         wake_unlock(&state->debugger_wake_lock);
 486 }
 487
 488 static irqreturn_t wakeup_irq_handler(int irq, void *dev)
 489 {
 490         struct fiq_debugger_state *state = dev;
 491
 492         if (!state->no_sleep)
 493                 debug_puts(state, "WAKEUP\n");
 494         if (state->ignore_next_wakeup_irq)
 495                 state->ignore_next_wakeup_irq = false;
 496         else if (!state->uart_clk_enabled) {
 497                 wake_lock(&state->debugger_wake_lock);
 498                 if (state->clk)
 499                         clk_enable(state->clk);
 500                 state->uart_clk_enabled = true;
 501                 disable_wakeup_irq(state);
 502                 mod_timer(&state->sleep_timer, jiffies + HZ / 2);
 503         }
 504         return IRQ_HANDLED;
 505 }
 506
 507 static irqreturn_t debug_irq(int irq, void *dev)
 508 {
 509         struct fiq_debugger_state *state = dev;
 510         if (state->pdata->force_irq_ack)
 511                 state->pdata->force_irq_ack(state->pdev, state->signal_irq);
 512
 513         if (!state->no_sleep) {
 514                 wake_lock(&state->debugger_wake_lock);
 515                 mod_timer(&state->sleep_timer, jiffies + HZ * 5);
 516         }
 517 #if defined(CONFIG_FIQ_DEBUGGER_CONSOLE)
 518         if (state->tty) {
 519                 int i;
 520                 int count = fiq_debugger_ringbuf_level(state->tty_rbuf);
 521                 for (i = 0; i < count; i++) {
 522                         int c = fiq_debugger_ringbuf_peek(state->tty_rbuf, i);
 523                         tty_insert_flip_char(state->tty, c, TTY_NORMAL);
 524                         if (!fiq_debugger_ringbuf_consume(state->tty_rbuf, 1))
 525                                 pr_warn("fiq tty failed to consume byte\n");
 526                 }
 527                 tty_flip_buffer_push(state->tty);
 528         }
 529 #endif
 530         if (state->debug_busy) {
 531                 struct kdbg_ctxt ctxt;
 532
 533                 ctxt.printf = debug_printf_nfiq;
 534                 ctxt.cookie = state;
 535                 kernel_debugger(&ctxt, state->debug_cmd);
 536                 debug_prompt(state);
 537
 538                 state->debug_busy = 0;
 539         }
 540         return IRQ_HANDLED;
 541 }
 542
 543 static int debug_getc(struct fiq_debugger_state *state)
 544 {
 545         return state->pdata->uart_getc(state->pdev);
 546 }
 547
 548 static void debug_fiq(struct fiq_glue_handler *h, void *regs, void *svc_sp)
 549 {
 550         struct fiq_debugger_state *state =
 551                 container_of(h, struct fiq_debugger_state, handler);
 552         int c;
 553         static int last_c;
 554         int count = 0;
 555
 556         while ((c = debug_getc(state)) != FIQ_DEBUGGER_NO_CHAR) {
 557                 count++;
 558                 if (!state->debug_enable) {
 559                         if ((c == 13) || (c == 10)) {
 560                                 state->debug_enable = true;
 561                                 state->debug_count = 0;
 562                                 debug_prompt(state);
 563                         }
 564                 } else if (c == FIQ_DEBUGGER_BREAK) {
 565                         state->console_enable = false;
 566                         debug_puts(state, "fiq debugger mode\n");
 567                         state->debug_count = 0;
 568                         debug_prompt(state);
 569 #ifdef CONFIG_FIQ_DEBUGGER_CONSOLE
 570                 } else if (state->console_enable && state->tty_rbuf) {
 571                         fiq_debugger_ringbuf_push(state->tty_rbuf, c);
 572                         debug_force_irq(state);
 573 #endif
 574                 } else if ((c >= ' ') && (c < 127)) {
 575                         if (state->debug_count < (DEBUG_MAX - 1)) {
 576                                 state->debug_buf[state->debug_count++] = c;
 577                                 state->pdata->uart_putc(state->pdev, c);
 578                         }
 579                 } else if ((c == 8) || (c == 127)) {
 580                         if (state->debug_count > 0) {
 581                                 state->debug_count--;
 582                                 state->pdata->uart_putc(state->pdev, 8);
 583                                 state->pdata->uart_putc(state->pdev, ' ');
 584                                 state->pdata->uart_putc(state->pdev, 8);
 585                         }
 586                 } else if ((c == 13) || (c == 10)) {
 587                         if (c == '\r' || (c == '\n' && last_c != '\r')) {
 588                                 state->pdata->uart_putc(state->pdev, '\r');
 589                                 state->pdata->uart_putc(state->pdev, '\n');
 590                         }
 591                         if (state->debug_count) {
 592                                 state->debug_buf[state->debug_count] = 0;
 593                                 state->debug_count = 0;
 594                                 debug_exec(state, state->debug_buf,
 595                                         regs, svc_sp);
 596                         } else {
 597                                 debug_prompt(state);
 598                         }
 599                 }
 600                 last_c = c;
 601         }
 602         debug_uart_flush(state);
 603         if (state->pdata->fiq_ack)
 604                 state->pdata->fiq_ack(state->pdev, state->fiq);
 605
 606         /* poke sleep timer if necessary */
 607         if (state->debug_enable && !state->no_sleep)
 608                 debug_force_irq(state);
 609 }
 610
 611 static void debug_resume(struct fiq_glue_handler *h)
 612 {
 613         struct fiq_debugger_state *state =
 614                 container_of(h, struct fiq_debugger_state, handler);
 615         if (state->pdata->uart_resume)
 616                 state->pdata->uart_resume(state->pdev);
 617 }
 618
 619 #if defined(CONFIG_FIQ_DEBUGGER_CONSOLE)
 620 struct tty_driver *debug_console_device(struct console *co, int *index)
 621 {
 622         struct fiq_debugger_state *state;
 623         state = container_of(co, struct fiq_debugger_state, console);
 624         *index = 0;
 625         return state->tty_driver;
 626 }
 627
 628 static void debug_console_write(struct console *co,
 629                                 const char *s, unsigned int count)
 630 {
 631         struct fiq_debugger_state *state;
 632
 633         state = container_of(co, struct fiq_debugger_state, console);
 634
 635         if (!state->console_enable)
 636                 return;
 637
 638         while (count--) {
 639                 if (*s == '\n')
 640                         state->pdata->uart_putc(state->pdev, '\r');
 641                 state->pdata->uart_putc(state->pdev, *s++);
 642         }
 643         debug_uart_flush(state);
 644 }
 645
 646 static struct console fiq_debugger_console = {
 647         .name = "ttyFIQ",
 648         .device = debug_console_device,
 649         .write = debug_console_write,
 650         .flags = CON_PRINTBUFFER | CON_ANYTIME | CON_ENABLED,
 651 };
 652
 653 int fiq_tty_open(struct tty_struct *tty, struct file *filp)
 654 {
 655         struct fiq_debugger_state *state = tty->driver->driver_state;
 656         if (state->tty_open_count++)
 657                 return 0;
 658
 659         tty->driver_data = state;
 660         state->tty = tty;
 661         return 0;
 662 }
 663
 664 void fiq_tty_close(struct tty_struct *tty, struct file *filp)
 665 {
 666         struct fiq_debugger_state *state = tty->driver_data;
 667         if (--state->tty_open_count)
 668                 return;
 669         state->tty = NULL;
 670 }
 671
 672 int  fiq_tty_write(struct tty_struct *tty, const unsigned char *buf, int count)
 673 {
 674         int i;
 675         struct fiq_debugger_state *state = tty->driver_data;
 676
 677         if (!state->console_enable)
 678                 return count;
 679
 680         if (state->clk)
 681                 clk_enable(state->clk);
 682         for (i = 0; i < count; i++)
 683                 state->pdata->uart_putc(state->pdev, *buf++);
 684         if (state->clk)
 685                 clk_disable(state->clk);
 686
 687         return count;
 688 }
 689
 690 int  fiq_tty_write_room(struct tty_struct *tty)
 691 {
 692         return 1024;
 693 }
 694
 695 static const struct tty_operations fiq_tty_driver_ops = {
 696         .write = fiq_tty_write,
 697         .write_room = fiq_tty_write_room,
 698         .open = fiq_tty_open,
 699         .close = fiq_tty_close,
 700 };
 701
 702 static int fiq_debugger_tty_init(struct fiq_debugger_state *state)
 703 {
 704         int ret = -EINVAL;
 705
 706         state->tty_driver = alloc_tty_driver(1);
 707         if (!state->tty_driver) {
 708                 pr_err("Failed to allocate fiq debugger tty\n");
 709                 return -ENOMEM;
 710         }
 711
 712         state->tty_driver->owner                = THIS_MODULE;
 713         state->tty_driver->driver_name  = "fiq-debugger";
 714         state->tty_driver->name         = "ttyFIQ";
 715         state->tty_driver->type         = TTY_DRIVER_TYPE_SERIAL;
 716         state->tty_driver->subtype      = SERIAL_TYPE_NORMAL;
 717         state->tty_driver->init_termios = tty_std_termios;
 718         state->tty_driver->init_termios.c_cflag =
 719                                         B115200 | CS8 | CREAD | HUPCL | CLOCAL;
 720         state->tty_driver->init_termios.c_ispeed =
 721                 state->tty_driver->init_termios.c_ospeed = 115200;
 722         state->tty_driver->flags                = TTY_DRIVER_REAL_RAW;
 723         tty_set_operations(state->tty_driver, &fiq_tty_driver_ops);
 724         state->tty_driver->driver_state = state;
 725
 726         ret = tty_register_driver(state->tty_driver);
 727         if (ret) {
 728                 pr_err("Failed to register fiq tty: %d\n", ret);
 729                 goto err;
 730         }
 731
 732         state->tty_rbuf = fiq_debugger_ringbuf_alloc(1024);
 733         if (!state->tty_rbuf) {
 734                 pr_err("Failed to allocate fiq debugger ringbuf\n");
 735                 ret = -ENOMEM;
 736                 goto err;
 737         }
 738
 739         pr_info("Registered FIQ tty driver %p\n", state->tty_driver);
 740         return 0;
 741
 742 err:
 743         fiq_debugger_ringbuf_free(state->tty_rbuf);
 744         state->tty_rbuf = NULL;
 745         put_tty_driver(state->tty_driver);
 746         return ret;
 747 }
 748 #endif
 749
 750 static int fiq_debugger_probe(struct platform_device *pdev)
 751 {
 752         int ret;
 753         struct fiq_debugger_pdata *pdata = dev_get_platdata(&pdev->dev);
 754         struct fiq_debugger_state *state;
 755
 756         if (!pdata->uart_getc || !pdata->uart_putc || !pdata->fiq_enable)
 757                 return -EINVAL;
 758
 759         state = kzalloc(sizeof(*state), GFP_KERNEL);
 760         state->handler.fiq = debug_fiq;
 761         state->handler.resume = debug_resume;
 762         setup_timer(&state->sleep_timer, sleep_timer_expired,
 763                     (unsigned long)state);
 764         state->pdata = pdata;
 765         state->pdev = pdev;
 766         state->no_sleep = initial_no_sleep;
 767         state->debug_enable = initial_debug_enable;
 768         state->console_enable = initial_console_enable;
 769
 770         state->fiq = platform_get_irq_byname(pdev, "fiq");
 771         state->signal_irq = platform_get_irq_byname(pdev, "signal");
 772         state->wakeup_irq = platform_get_irq_byname(pdev, "wakeup");
 773
 774         if (state->wakeup_irq < 0)
 775                 state->no_sleep = true;
 776         state->ignore_next_wakeup_irq = !state->no_sleep;
 777
 778         wake_lock_init(&state->debugger_wake_lock,
 779                         WAKE_LOCK_SUSPEND, "serial-debug");
 780
 781         state->clk = clk_get(&pdev->dev, NULL);
 782         if (IS_ERR(state->clk))
 783                 state->clk = NULL;
 784
 785         if (state->clk)
 786                 clk_enable(state->clk);
 787
 788         if (pdata->uart_init) {
 789                 ret = pdata->uart_init(pdev);
 790                 if (ret)
 791                         goto err_uart_init;
 792         }
 793
 794         debug_printf_nfiq(state, "<hit enter %sto activate fiq debugger>\n",
 795                                 state->no_sleep ? "" : "twice ");
 796
 797         ret = fiq_glue_register_handler(&state->handler);
 798         if (ret) {
 799                 pr_err("serial_debugger: could not install fiq handler\n");
 800                 goto err_register_fiq;
 801         }
 802
 803         pdata->fiq_enable(pdev, state->fiq, 1);
 804
 805         if (state->clk)
 806                 clk_disable(state->clk);
 807
 808         ret = request_irq(state->signal_irq, debug_irq,
 809                           IRQF_TRIGGER_RISING, "debug", state);
 810         if (ret)
 811                 pr_err("serial_debugger: could not install signal_irq");
 812
 813         if (state->wakeup_irq >= 0) {
 814                 ret = request_irq(state->wakeup_irq, wakeup_irq_handler,
 815                                   IRQF_TRIGGER_FALLING | IRQF_DISABLED,
 816                                   "debug-wakeup", state);
 817                 if (ret) {
 818                         pr_err("serial_debugger: "
 819                                 "could not install wakeup irq\n");
 820                         state->wakeup_irq = -1;
 821                 } else {
 822                         ret = enable_irq_wake(state->wakeup_irq);
 823                         if (ret) {
 824                                 pr_err("serial_debugger: "
 825                                         "could not enable wakeup\n");
 826                                 state->wakeup_irq_no_set_wake = true;
 827                         }
 828                 }
 829         }
 830         if (state->no_sleep)
 831                 wakeup_irq_handler(state->wakeup_irq, state);
 832
 833 #if defined(CONFIG_FIQ_DEBUGGER_CONSOLE)
 834         state->console = fiq_debugger_console;
 835         register_console(&state->console);
 836         fiq_debugger_tty_init(state);
 837 #endif
 838         return 0;
 839
 840 err_register_fiq:
 841         if (pdata->uart_free)
 842                 pdata->uart_free(pdev);
 843 err_uart_init:
 844         kfree(state);
 845         if (state->clk)
 846                 clk_put(state->clk);
 847         return ret;
 848 }
 849
 850 static struct platform_driver fiq_debugger_driver = {
 851         .probe = fiq_debugger_probe,
 852         .driver.name = "fiq_debugger",
 853 };
 854
 855 static int __init fiq_debugger_init(void)
 856 {
 857         return platform_driver_register(&fiq_debugger_driver);
 858 }
 859
 860 postcore_initcall(fiq_debugger_init);