2 * File: arch/blackfin/kernel/traps.c
4 * Author: Hamish Macdonald
7 * Description: uses S/W interrupt 15 for the system calls
10 * Copyright 2004-2006 Analog Devices Inc.
12 * Bugs: Enter bugs at http://blackfin.uclinux.org/
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or
17 * (at your option) any later version.
19 * This program is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU General Public License for more details.
24 * You should have received a copy of the GNU General Public License
25 * along with this program; if not, see the file COPYING, or write
26 * to the Free Software Foundation, Inc.,
27 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
30 #include <linux/uaccess.h>
31 #include <linux/interrupt.h>
32 #include <linux/module.h>
33 #include <linux/kallsyms.h>
35 #include <asm/traps.h>
36 #include <asm/cacheflush.h>
37 #include <asm/blackfin.h>
38 #include <asm/irq_handler.h>
39 #include <asm/trace.h>
42 # include <linux/debugger.h>
43 # include <linux/kgdb.h>
46 /* Initiate the event table handler */
47 void __init trap_init(void)
50 bfin_write_EVT3(trap);
54 int kstack_depth_to_print = 48;
56 #ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON
57 static int printk_address(unsigned long address)
59 struct vm_list_struct *vml;
60 struct task_struct *p;
64 #ifdef CONFIG_KALLSYMS
65 unsigned long symsize;
71 /* look up the address and see if we are in kernel space */
72 symname = kallsyms_lookup(address, &symsize, &offset, &modname, namebuf);
75 /* yeah! kernel space! */
78 return printk("<0x%p> { %s%s%s%s + 0x%lx }",
79 (void *)address, delim, modname, delim, symname,
80 (unsigned long)offset);
85 /* looks like we're off in user-land, so let's walk all the
86 * mappings of all our processes and see if we can't be a whee
89 write_lock_irq(&tasklist_lock);
95 vml = mm->context.vmlist;
97 struct vm_area_struct *vma = vml->vma;
99 if (address >= vma->vm_start && address < vma->vm_end) {
100 char *name = p->comm;
101 struct file *file = vma->vm_file;
104 name = d_path(file->f_dentry,
110 /* FLAT does not have its text aligned to the start of
111 * the map while FDPIC ELF does ...
114 (address > current->mm->start_code) &&
115 (address < current->mm->end_code))
116 offset = address - current->mm->start_code;
118 offset = (address - vma->vm_start) + (vma->vm_pgoff << PAGE_SHIFT);
120 write_unlock_irq(&tasklist_lock);
122 return printk("<0x%p> [ %s + 0x%lx ]",
123 (void *)address, name, offset);
130 write_unlock_irq(&tasklist_lock);
132 /* we were unable to find this address anywhere */
133 return printk("[<0x%p>]", (void *)address);
137 asmlinkage void double_fault_c(struct pt_regs *fp)
139 printk(KERN_EMERG "\n" KERN_EMERG "Double Fault\n");
140 dump_bfin_regs(fp, (void *)fp->retx);
141 panic("Double Fault - unrecoverable event\n");
145 asmlinkage void trap_c(struct pt_regs *fp)
147 #ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON
152 unsigned long trapnr = fp->seqstat & SEQSTAT_EXCAUSE;
155 # define CHK_DEBUGGER_TRAP() \
157 CHK_DEBUGGER(trapnr, sig, info.si_code, fp, ); \
159 # define CHK_DEBUGGER_TRAP_MAYBE() \
161 if (kgdb_connected) \
162 CHK_DEBUGGER_TRAP(); \
165 # define CHK_DEBUGGER_TRAP() do { } while (0)
166 # define CHK_DEBUGGER_TRAP_MAYBE() do { } while (0)
169 trace_buffer_save(j);
171 /* trap_c() will be called for exceptions. During exceptions
172 * processing, the pc value should be set with retx value.
173 * With this change we can cleanup some code in signal.c- TODO
175 fp->orig_pc = fp->retx;
176 /* printk("exception: 0x%x, ipend=%x, reti=%x, retx=%x\n",
177 trapnr, fp->ipend, fp->pc, fp->retx); */
179 /* send the appropriate signal to the user program */
182 /* This table works in conjuction with the one in ./mach-common/entry.S
183 * Some exceptions are handled there (in assembly, in exception space)
184 * Some are handled here, (in C, in interrupt space)
185 * Some, like CPLB, are handled in both, where the normal path is
186 * handled in assembly/exception space, and the error path is handled
190 /* 0x00 - Linux Syscall, getting here is an error */
191 /* 0x01 - userspace gdb breakpoint, handled here */
193 info.si_code = TRAP_ILLTRAP;
195 CHK_DEBUGGER_TRAP_MAYBE();
196 /* Check if this is a breakpoint in kernel space */
197 if (fp->ipend & 0xffc0)
202 case VEC_EXCPT02 : /* gdb connection */
203 info.si_code = TRAP_ILLTRAP;
208 /* 0x02 - User Defined, Caught by default */
210 /* 0x03 - User Defined, userspace stack overflow */
212 info.si_code = SEGV_STACKFLOW;
214 printk(KERN_EMERG EXC_0x03);
217 /* 0x04 - User Defined, Caught by default */
218 /* 0x05 - User Defined, Caught by default */
219 /* 0x06 - User Defined, Caught by default */
220 /* 0x07 - User Defined, Caught by default */
221 /* 0x08 - User Defined, Caught by default */
222 /* 0x09 - User Defined, Caught by default */
223 /* 0x0A - User Defined, Caught by default */
224 /* 0x0B - User Defined, Caught by default */
225 /* 0x0C - User Defined, Caught by default */
226 /* 0x0D - User Defined, Caught by default */
227 /* 0x0E - User Defined, Caught by default */
228 /* 0x0F - User Defined, Caught by default */
229 /* 0x10 HW Single step, handled here */
231 info.si_code = TRAP_STEP;
233 CHK_DEBUGGER_TRAP_MAYBE();
234 /* Check if this is a single step in kernel space */
235 if (fp->ipend & 0xffc0)
239 /* 0x11 - Trace Buffer Full, handled here */
241 info.si_code = TRAP_TRACEFLOW;
243 printk(KERN_EMERG EXC_0x11);
246 /* 0x12 - Reserved, Caught by default */
247 /* 0x13 - Reserved, Caught by default */
248 /* 0x14 - Reserved, Caught by default */
249 /* 0x15 - Reserved, Caught by default */
250 /* 0x16 - Reserved, Caught by default */
251 /* 0x17 - Reserved, Caught by default */
252 /* 0x18 - Reserved, Caught by default */
253 /* 0x19 - Reserved, Caught by default */
254 /* 0x1A - Reserved, Caught by default */
255 /* 0x1B - Reserved, Caught by default */
256 /* 0x1C - Reserved, Caught by default */
257 /* 0x1D - Reserved, Caught by default */
258 /* 0x1E - Reserved, Caught by default */
259 /* 0x1F - Reserved, Caught by default */
260 /* 0x20 - Reserved, Caught by default */
261 /* 0x21 - Undefined Instruction, handled here */
263 info.si_code = ILL_ILLOPC;
265 printk(KERN_EMERG EXC_0x21);
268 /* 0x22 - Illegal Instruction Combination, handled here */
270 info.si_code = ILL_ILLPARAOP;
272 printk(KERN_EMERG EXC_0x22);
275 /* 0x23 - Data CPLB Protection Violation,
276 normal case is handled in _cplb_hdr */
278 info.si_code = ILL_CPLB_VI;
280 printk(KERN_EMERG EXC_0x23);
283 /* 0x24 - Data access misaligned, handled here */
285 info.si_code = BUS_ADRALN;
287 printk(KERN_EMERG EXC_0x24);
290 /* 0x25 - Unrecoverable Event, handled here */
292 info.si_code = ILL_ILLEXCPT;
294 printk(KERN_EMERG EXC_0x25);
297 /* 0x26 - Data CPLB Miss, normal case is handled in _cplb_hdr,
298 error case is handled here */
300 info.si_code = BUS_ADRALN;
302 printk(KERN_EMERG EXC_0x26);
305 /* 0x27 - Data CPLB Multiple Hits - Linux Trap Zero, handled here */
307 info.si_code = ILL_CPLB_MULHIT;
308 #ifdef CONFIG_DEBUG_HUNT_FOR_ZERO
310 printk(KERN_EMERG "\n"
311 KERN_EMERG "NULL pointer access (probably)\n");
314 printk(KERN_EMERG EXC_0x27);
318 /* 0x28 - Emulation Watchpoint, handled here */
320 info.si_code = TRAP_WATCHPT;
323 CHK_DEBUGGER_TRAP_MAYBE();
324 /* Check if this is a watchpoint in kernel space */
325 if (fp->ipend & 0xffc0)
330 /* 0x29 - Instruction fetch access error (535 only) */
331 case VEC_ISTRU_VL: /* ADSP-BF535 only (MH) */
332 info.si_code = BUS_OPFETCH;
334 printk(KERN_EMERG "BF535: VEC_ISTRU_VL\n");
338 /* 0x29 - Reserved, Caught by default */
340 /* 0x2A - Instruction fetch misaligned, handled here */
342 info.si_code = BUS_ADRALN;
344 printk(KERN_EMERG EXC_0x2A);
347 /* 0x2B - Instruction CPLB protection Violation,
348 handled in _cplb_hdr */
350 info.si_code = ILL_CPLB_VI;
352 printk(KERN_EMERG EXC_0x2B);
355 /* 0x2C - Instruction CPLB miss, handled in _cplb_hdr */
357 info.si_code = ILL_CPLB_MISS;
359 printk(KERN_EMERG EXC_0x2C);
362 /* 0x2D - Instruction CPLB Multiple Hits, handled here */
363 case VEC_CPLB_I_MHIT:
364 info.si_code = ILL_CPLB_MULHIT;
365 #ifdef CONFIG_DEBUG_HUNT_FOR_ZERO
367 printk(KERN_EMERG "\n\nJump to address 0 - 0x0fff\n");
370 printk(KERN_EMERG EXC_0x2D);
374 /* 0x2E - Illegal use of Supervisor Resource, handled here */
376 info.si_code = ILL_PRVOPC;
378 printk(KERN_EMERG EXC_0x2E);
381 /* 0x2F - Reserved, Caught by default */
382 /* 0x30 - Reserved, Caught by default */
383 /* 0x31 - Reserved, Caught by default */
384 /* 0x32 - Reserved, Caught by default */
385 /* 0x33 - Reserved, Caught by default */
386 /* 0x34 - Reserved, Caught by default */
387 /* 0x35 - Reserved, Caught by default */
388 /* 0x36 - Reserved, Caught by default */
389 /* 0x37 - Reserved, Caught by default */
390 /* 0x38 - Reserved, Caught by default */
391 /* 0x39 - Reserved, Caught by default */
392 /* 0x3A - Reserved, Caught by default */
393 /* 0x3B - Reserved, Caught by default */
394 /* 0x3C - Reserved, Caught by default */
395 /* 0x3D - Reserved, Caught by default */
396 /* 0x3E - Reserved, Caught by default */
397 /* 0x3F - Reserved, Caught by default */
399 info.si_code = TRAP_ILLTRAP;
401 printk(KERN_EMERG "Caught Unhandled Exception, code = %08lx\n",
402 (fp->seqstat & SEQSTAT_EXCAUSE));
407 if (sig != 0 && sig != SIGTRAP) {
409 dump_bfin_regs(fp, (void *)fp->retx);
410 dump_bfin_trace_buffer();
411 show_stack(current, &stack);
412 if (current->mm == NULL)
413 panic("Kernel exception");
417 info.si_addr = (void *)fp->pc;
418 force_sig_info(sig, &info, current);
420 /* if the address that we are about to return to is not valid, set it
421 * to a valid address, if we have a current application or panic
423 if (!(fp->pc <= physical_mem_end
424 #if L1_CODE_LENGTH != 0
425 || (fp->pc >= L1_CODE_START &&
426 fp->pc <= (L1_CODE_START + L1_CODE_LENGTH))
430 fp->pc = current->mm->start_code;
433 "I can't return to memory that doesn't exist"
434 " - bad things happen\n");
435 panic("Help - I've fallen and can't get up\n");
439 trace_buffer_restore(j);
443 /* Typical exception handling routines */
445 #define EXPAND_LEN ((1 << CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN) * 256 - 1)
447 void dump_bfin_trace_buffer(void)
449 #ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON
451 #ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND
455 trace_buffer_save(tflags);
457 printk(KERN_EMERG "Hardware Trace:\n");
459 if (likely(bfin_read_TBUFSTAT() & TBUFCNT)) {
460 for (; bfin_read_TBUFSTAT() & TBUFCNT; i++) {
461 printk(KERN_EMERG "%4i Target : ", i);
462 printk_address((unsigned long)bfin_read_TBUF());
463 printk("\n" KERN_EMERG " Source : ");
464 printk_address((unsigned long)bfin_read_TBUF());
469 #ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND
470 if (trace_buff_offset)
471 index = trace_buff_offset/4 - 1;
475 j = (1 << CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN) * 128;
477 printk(KERN_EMERG "%4i Target : ", i);
478 printk_address(software_trace_buff[index]);
482 printk("\n" KERN_EMERG " Source : ");
483 printk_address(software_trace_buff[index]);
493 trace_buffer_restore(tflags);
496 EXPORT_SYMBOL(dump_bfin_trace_buffer);
498 static void show_trace(struct task_struct *tsk, unsigned long *sp)
502 printk("\nCall Trace:");
503 #ifdef CONFIG_KALLSYMS
507 while (!kstack_end(sp)) {
510 * If the address is either in the text segment of the
511 * kernel, or in the region which contains vmalloc'ed
512 * memory, it *may* be the address of a calling
513 * routine; if so, print it so that someone tracing
514 * down the cause of the crash will be able to figure
515 * out the call path that was taken.
517 if (kernel_text_address(addr))
524 void show_stack(struct task_struct *task, unsigned long *stack)
526 unsigned long *endstack, addr;
529 /* Cannot call dump_bfin_trace_buffer() here as show_stack() is
530 * called externally in some places in the kernel.
535 stack = (unsigned long *)task->thread.ksp;
537 stack = (unsigned long *)&stack;
540 addr = (unsigned long)stack;
541 endstack = (unsigned long *)PAGE_ALIGN(addr);
543 printk(KERN_EMERG "Stack from %08lx:", (unsigned long)stack);
544 for (i = 0; i < kstack_depth_to_print; i++) {
545 if (stack + 1 > endstack)
548 printk("\n" KERN_EMERG " ");
549 printk(" %08lx", *stack++);
552 show_trace(task, stack);
555 void dump_stack(void)
558 #ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON
561 trace_buffer_save(tflags);
562 dump_bfin_trace_buffer();
563 show_stack(current, &stack);
564 trace_buffer_restore(tflags);
567 EXPORT_SYMBOL(dump_stack);
569 void dump_bfin_regs(struct pt_regs *fp, void *retaddr)
572 printk(KERN_EMERG "\n" KERN_EMERG "CURRENT PROCESS:\n"
574 printk(KERN_EMERG "COMM=%s PID=%d\n",
575 current->comm, current->pid);
578 (KERN_EMERG "\n" KERN_EMERG
579 "No Valid pid - Either things are really messed up,"
580 " or you are in the kernel\n");
584 printk(KERN_EMERG "TEXT = 0x%p-0x%p DATA = 0x%p-0x%p\n"
585 KERN_EMERG "BSS = 0x%p-0x%p USER-STACK = 0x%p\n"
587 (void *)current->mm->start_code,
588 (void *)current->mm->end_code,
589 (void *)current->mm->start_data,
590 (void *)current->mm->end_data,
591 (void *)current->mm->end_data,
592 (void *)current->mm->brk,
593 (void *)current->mm->start_stack);
596 printk(KERN_EMERG "return address: [0x%p]; contents of:", retaddr);
597 if (retaddr != 0 && retaddr <= (void *)physical_mem_end
598 #if L1_CODE_LENGTH != 0
599 /* FIXME: Copy the code out of L1 Instruction SRAM through dma
601 && !(retaddr >= (void *)L1_CODE_START
602 && retaddr < (void *)(L1_CODE_START + L1_CODE_LENGTH))
605 int i = ((unsigned int)retaddr & 0xFFFFFFF0) - 32;
606 unsigned short x = 0;
607 for (; i < ((unsigned int)retaddr & 0xFFFFFFF0) + 32; i += 2) {
609 printk("\n" KERN_EMERG "0x%08x: ", i);
611 if (get_user(x, (unsigned short *)i))
613 #ifndef CONFIG_DEBUG_HWERR
614 /* If one of the last few instructions was a STI
615 * it is likely that the error occured awhile ago
616 * and we just noticed
618 if (x >= 0x0040 && x <= 0x0047 && i <= 0)
619 panic("\n\nWARNING : You should reconfigure"
620 " the kernel to turn on\n"
621 " 'Hardware error interrupt"
623 " The rest of this error"
626 if (i == (unsigned int)retaddr)
631 printk("\n" KERN_EMERG "\n");
634 "Cannot look at the [PC] for it is"
635 "in unreadable L1 SRAM - sorry\n");
639 "RETE: %08lx RETN: %08lx RETX: %08lx RETS: %08lx\n",
640 fp->rete, fp->retn, fp->retx, fp->rets);
641 printk(KERN_EMERG "IPEND: %04lx SYSCFG: %04lx\n",
642 fp->ipend, fp->syscfg);
643 printk(KERN_EMERG "SEQSTAT: %08lx SP: %08lx\n",
644 (long)fp->seqstat, (long)fp);
645 printk(KERN_EMERG "R0: %08lx R1: %08lx R2: %08lx R3: %08lx\n",
646 fp->r0, fp->r1, fp->r2, fp->r3);
647 printk(KERN_EMERG "R4: %08lx R5: %08lx R6: %08lx R7: %08lx\n",
648 fp->r4, fp->r5, fp->r6, fp->r7);
649 printk(KERN_EMERG "P0: %08lx P1: %08lx P2: %08lx P3: %08lx\n",
650 fp->p0, fp->p1, fp->p2, fp->p3);
652 "P4: %08lx P5: %08lx FP: %08lx\n",
653 fp->p4, fp->p5, fp->fp);
655 "A0.w: %08lx A0.x: %08lx A1.w: %08lx A1.x: %08lx\n",
656 fp->a0w, fp->a0x, fp->a1w, fp->a1x);
658 printk(KERN_EMERG "LB0: %08lx LT0: %08lx LC0: %08lx\n",
659 fp->lb0, fp->lt0, fp->lc0);
660 printk(KERN_EMERG "LB1: %08lx LT1: %08lx LC1: %08lx\n",
661 fp->lb1, fp->lt1, fp->lc1);
662 printk(KERN_EMERG "B0: %08lx L0: %08lx M0: %08lx I0: %08lx\n",
663 fp->b0, fp->l0, fp->m0, fp->i0);
664 printk(KERN_EMERG "B1: %08lx L1: %08lx M1: %08lx I1: %08lx\n",
665 fp->b1, fp->l1, fp->m1, fp->i1);
666 printk(KERN_EMERG "B2: %08lx L2: %08lx M2: %08lx I2: %08lx\n",
667 fp->b2, fp->l2, fp->m2, fp->i2);
668 printk(KERN_EMERG "B3: %08lx L3: %08lx M3: %08lx I3: %08lx\n",
669 fp->b3, fp->l3, fp->m3, fp->i3);
671 printk(KERN_EMERG "\n" KERN_EMERG "USP: %08lx ASTAT: %08lx\n",
673 if ((long)fp->seqstat & SEQSTAT_EXCAUSE) {
674 printk(KERN_EMERG "DCPLB_FAULT_ADDR=%p\n",
675 (void *)bfin_read_DCPLB_FAULT_ADDR());
676 printk(KERN_EMERG "ICPLB_FAULT_ADDR=%p\n",
677 (void *)bfin_read_ICPLB_FAULT_ADDR());
683 #ifdef CONFIG_SYS_BFIN_SPINLOCK_L1
684 asmlinkage int sys_bfin_spinlock(int *spinlock)__attribute__((l1_text));
687 asmlinkage int sys_bfin_spinlock(int *spinlock)
693 ret = get_user(tmp, spinlock);
698 put_user(tmp, spinlock);
704 int bfin_request_exception(unsigned int exception, void (*handler)(void))
706 void (*curr_handler)(void);
708 if (exception > 0x3F)
711 curr_handler = ex_table[exception];
713 if (curr_handler != ex_replaceable)
716 ex_table[exception] = handler;
720 EXPORT_SYMBOL(bfin_request_exception);
722 int bfin_free_exception(unsigned int exception, void (*handler)(void))
724 void (*curr_handler)(void);
726 if (exception > 0x3F)
729 curr_handler = ex_table[exception];
731 if (curr_handler != handler)
734 ex_table[exception] = ex_replaceable;
738 EXPORT_SYMBOL(bfin_free_exception);
740 void panic_cplb_error(int cplb_panic, struct pt_regs *fp)
742 switch (cplb_panic) {
743 case CPLB_NO_UNLOCKED:
744 printk(KERN_EMERG "All CPLBs are locked\n");
748 case CPLB_NO_ADDR_MATCH:
750 case CPLB_UNKNOWN_ERR:
751 printk(KERN_EMERG "Unknown CPLB Exception\n");
755 printk(KERN_EMERG "DCPLB_FAULT_ADDR=%p\n", (void *)bfin_read_DCPLB_FAULT_ADDR());
756 printk(KERN_EMERG "ICPLB_FAULT_ADDR=%p\n", (void *)bfin_read_ICPLB_FAULT_ADDR());
757 dump_bfin_regs(fp, (void *)fp->retx);
759 panic("Unrecoverable event\n");