/* * File: arch/blackfin/kernel/traps.c * Based on: * Author: Hamish Macdonald * * Created: * Description: uses S/W interrupt 15 for the system calls * * Modified: * Copyright 2004-2006 Analog Devices Inc. * * Bugs: Enter bugs at http://blackfin.uclinux.org/ * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, see the file COPYING, or write * to the Free Software Foundation, Inc., * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ #include #include #include #include #include #include #include #include #include #include #ifdef CONFIG_KGDB # include # include #endif /* Initiate the event table handler */ void __init trap_init(void) { CSYNC(); bfin_write_EVT3(trap); CSYNC(); } int kstack_depth_to_print = 48; #ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON static int printk_address(unsigned long address) { struct vm_list_struct *vml; struct task_struct *p; struct mm_struct *mm; unsigned long offset; #ifdef CONFIG_KALLSYMS unsigned long symsize; const char *symname; char *modname; char *delim = ":"; char namebuf[128]; /* look up the address and see if we are in kernel space */ symname = kallsyms_lookup(address, &symsize, &offset, &modname, namebuf); if (symname) { /* yeah! kernel space! */ if (!modname) modname = delim = ""; return printk("<0x%p> { %s%s%s%s + 0x%lx }", (void *)address, delim, modname, delim, symname, (unsigned long)offset); } #endif /* looks like we're off in user-land, so let's walk all the * mappings of all our processes and see if we can't be a whee * bit more specific */ write_lock_irq(&tasklist_lock); for_each_process(p) { mm = get_task_mm(p); if (!mm) continue; vml = mm->context.vmlist; while (vml) { struct vm_area_struct *vma = vml->vma; if (address >= vma->vm_start && address < vma->vm_end) { char *name = p->comm; struct file *file = vma->vm_file; if (file) { char _tmpbuf[256]; name = d_path(file->f_dentry, file->f_vfsmnt, _tmpbuf, sizeof(_tmpbuf)); } /* FLAT does not have its text aligned to the start of * the map while FDPIC ELF does ... */ if (current->mm && (address > current->mm->start_code) && (address < current->mm->end_code)) offset = address - current->mm->start_code; else offset = (address - vma->vm_start) + (vma->vm_pgoff << PAGE_SHIFT); write_unlock_irq(&tasklist_lock); return printk("<0x%p> [ %s + 0x%lx ]", (void *)address, name, offset); } vml = vml->next; } } write_unlock_irq(&tasklist_lock); /* we were unable to find this address anywhere */ return printk("[<0x%p>]", (void *)address); } #endif asmlinkage void double_fault_c(struct pt_regs *fp) { printk(KERN_EMERG "\n" KERN_EMERG "Double Fault\n"); dump_bfin_regs(fp, (void *)fp->retx); panic("Double Fault - unrecoverable event\n"); } asmlinkage void trap_c(struct pt_regs *fp) { #ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON int j; #endif int sig = 0; siginfo_t info; unsigned long trapnr = fp->seqstat & SEQSTAT_EXCAUSE; #ifdef CONFIG_KGDB # define CHK_DEBUGGER_TRAP() \ do { \ CHK_DEBUGGER(trapnr, sig, info.si_code, fp, ); \ } while (0) # define CHK_DEBUGGER_TRAP_MAYBE() \ do { \ if (kgdb_connected) \ CHK_DEBUGGER_TRAP(); \ } while (0) #else # define CHK_DEBUGGER_TRAP() do { } while (0) # define CHK_DEBUGGER_TRAP_MAYBE() do { } while (0) #endif trace_buffer_save(j); /* trap_c() will be called for exceptions. During exceptions * processing, the pc value should be set with retx value. * With this change we can cleanup some code in signal.c- TODO */ fp->orig_pc = fp->retx; /* printk("exception: 0x%x, ipend=%x, reti=%x, retx=%x\n", trapnr, fp->ipend, fp->pc, fp->retx); */ /* send the appropriate signal to the user program */ switch (trapnr) { /* This table works in conjuction with the one in ./mach-common/entry.S * Some exceptions are handled there (in assembly, in exception space) * Some are handled here, (in C, in interrupt space) * Some, like CPLB, are handled in both, where the normal path is * handled in assembly/exception space, and the error path is handled * here */ /* 0x00 - Linux Syscall, getting here is an error */ /* 0x01 - userspace gdb breakpoint, handled here */ case VEC_EXCPT01: info.si_code = TRAP_ILLTRAP; sig = SIGTRAP; CHK_DEBUGGER_TRAP_MAYBE(); /* Check if this is a breakpoint in kernel space */ if (fp->ipend & 0xffc0) return; else break; #ifdef CONFIG_KGDB case VEC_EXCPT02 : /* gdb connection */ info.si_code = TRAP_ILLTRAP; sig = SIGTRAP; CHK_DEBUGGER_TRAP(); return; #else /* 0x02 - User Defined, Caught by default */ #endif /* 0x03 - User Defined, userspace stack overflow */ case VEC_EXCPT03: info.si_code = SEGV_STACKFLOW; sig = SIGSEGV; printk(KERN_EMERG EXC_0x03); CHK_DEBUGGER_TRAP(); break; /* 0x04 - User Defined, Caught by default */ /* 0x05 - User Defined, Caught by default */ /* 0x06 - User Defined, Caught by default */ /* 0x07 - User Defined, Caught by default */ /* 0x08 - User Defined, Caught by default */ /* 0x09 - User Defined, Caught by default */ /* 0x0A - User Defined, Caught by default */ /* 0x0B - User Defined, Caught by default */ /* 0x0C - User Defined, Caught by default */ /* 0x0D - User Defined, Caught by default */ /* 0x0E - User Defined, Caught by default */ /* 0x0F - User Defined, Caught by default */ /* 0x10 HW Single step, handled here */ case VEC_STEP: info.si_code = TRAP_STEP; sig = SIGTRAP; CHK_DEBUGGER_TRAP_MAYBE(); /* Check if this is a single step in kernel space */ if (fp->ipend & 0xffc0) return; else break; /* 0x11 - Trace Buffer Full, handled here */ case VEC_OVFLOW: info.si_code = TRAP_TRACEFLOW; sig = SIGTRAP; printk(KERN_EMERG EXC_0x11); CHK_DEBUGGER_TRAP(); break; /* 0x12 - Reserved, Caught by default */ /* 0x13 - Reserved, Caught by default */ /* 0x14 - Reserved, Caught by default */ /* 0x15 - Reserved, Caught by default */ /* 0x16 - Reserved, Caught by default */ /* 0x17 - Reserved, Caught by default */ /* 0x18 - Reserved, Caught by default */ /* 0x19 - Reserved, Caught by default */ /* 0x1A - Reserved, Caught by default */ /* 0x1B - Reserved, Caught by default */ /* 0x1C - Reserved, Caught by default */ /* 0x1D - Reserved, Caught by default */ /* 0x1E - Reserved, Caught by default */ /* 0x1F - Reserved, Caught by default */ /* 0x20 - Reserved, Caught by default */ /* 0x21 - Undefined Instruction, handled here */ case VEC_UNDEF_I: info.si_code = ILL_ILLOPC; sig = SIGILL; printk(KERN_EMERG EXC_0x21); CHK_DEBUGGER_TRAP(); break; /* 0x22 - Illegal Instruction Combination, handled here */ case VEC_ILGAL_I: info.si_code = ILL_ILLPARAOP; sig = SIGILL; printk(KERN_EMERG EXC_0x22); CHK_DEBUGGER_TRAP(); break; /* 0x23 - Data CPLB Protection Violation, normal case is handled in _cplb_hdr */ case VEC_CPLB_VL: info.si_code = ILL_CPLB_VI; sig = SIGILL; printk(KERN_EMERG EXC_0x23); CHK_DEBUGGER_TRAP(); break; /* 0x24 - Data access misaligned, handled here */ case VEC_MISALI_D: info.si_code = BUS_ADRALN; sig = SIGBUS; printk(KERN_EMERG EXC_0x24); CHK_DEBUGGER_TRAP(); break; /* 0x25 - Unrecoverable Event, handled here */ case VEC_UNCOV: info.si_code = ILL_ILLEXCPT; sig = SIGILL; printk(KERN_EMERG EXC_0x25); CHK_DEBUGGER_TRAP(); break; /* 0x26 - Data CPLB Miss, normal case is handled in _cplb_hdr, error case is handled here */ case VEC_CPLB_M: info.si_code = BUS_ADRALN; sig = SIGBUS; printk(KERN_EMERG EXC_0x26); CHK_DEBUGGER_TRAP(); break; /* 0x27 - Data CPLB Multiple Hits - Linux Trap Zero, handled here */ case VEC_CPLB_MHIT: info.si_code = ILL_CPLB_MULHIT; #ifdef CONFIG_DEBUG_HUNT_FOR_ZERO sig = SIGSEGV; printk(KERN_EMERG "\n" KERN_EMERG "NULL pointer access (probably)\n"); #else sig = SIGILL; printk(KERN_EMERG EXC_0x27); #endif CHK_DEBUGGER_TRAP(); break; /* 0x28 - Emulation Watchpoint, handled here */ case VEC_WATCH: info.si_code = TRAP_WATCHPT; sig = SIGTRAP; pr_debug(EXC_0x28); CHK_DEBUGGER_TRAP_MAYBE(); /* Check if this is a watchpoint in kernel space */ if (fp->ipend & 0xffc0) return; else break; #ifdef CONFIG_BF535 /* 0x29 - Instruction fetch access error (535 only) */ case VEC_ISTRU_VL: /* ADSP-BF535 only (MH) */ info.si_code = BUS_OPFETCH; sig = SIGBUS; printk(KERN_EMERG "BF535: VEC_ISTRU_VL\n"); CHK_DEBUGGER_TRAP(); break; #else /* 0x29 - Reserved, Caught by default */ #endif /* 0x2A - Instruction fetch misaligned, handled here */ case VEC_MISALI_I: info.si_code = BUS_ADRALN; sig = SIGBUS; printk(KERN_EMERG EXC_0x2A); CHK_DEBUGGER_TRAP(); break; /* 0x2B - Instruction CPLB protection Violation, handled in _cplb_hdr */ case VEC_CPLB_I_VL: info.si_code = ILL_CPLB_VI; sig = SIGILL; printk(KERN_EMERG EXC_0x2B); CHK_DEBUGGER_TRAP(); break; /* 0x2C - Instruction CPLB miss, handled in _cplb_hdr */ case VEC_CPLB_I_M: info.si_code = ILL_CPLB_MISS; sig = SIGBUS; printk(KERN_EMERG EXC_0x2C); CHK_DEBUGGER_TRAP(); break; /* 0x2D - Instruction CPLB Multiple Hits, handled here */ case VEC_CPLB_I_MHIT: info.si_code = ILL_CPLB_MULHIT; #ifdef CONFIG_DEBUG_HUNT_FOR_ZERO sig = SIGSEGV; printk(KERN_EMERG "\n\nJump to address 0 - 0x0fff\n"); #else sig = SIGILL; printk(KERN_EMERG EXC_0x2D); #endif CHK_DEBUGGER_TRAP(); break; /* 0x2E - Illegal use of Supervisor Resource, handled here */ case VEC_ILL_RES: info.si_code = ILL_PRVOPC; sig = SIGILL; printk(KERN_EMERG EXC_0x2E); CHK_DEBUGGER_TRAP(); break; /* 0x2F - Reserved, Caught by default */ /* 0x30 - Reserved, Caught by default */ /* 0x31 - Reserved, Caught by default */ /* 0x32 - Reserved, Caught by default */ /* 0x33 - Reserved, Caught by default */ /* 0x34 - Reserved, Caught by default */ /* 0x35 - Reserved, Caught by default */ /* 0x36 - Reserved, Caught by default */ /* 0x37 - Reserved, Caught by default */ /* 0x38 - Reserved, Caught by default */ /* 0x39 - Reserved, Caught by default */ /* 0x3A - Reserved, Caught by default */ /* 0x3B - Reserved, Caught by default */ /* 0x3C - Reserved, Caught by default */ /* 0x3D - Reserved, Caught by default */ /* 0x3E - Reserved, Caught by default */ /* 0x3F - Reserved, Caught by default */ default: info.si_code = TRAP_ILLTRAP; sig = SIGTRAP; printk(KERN_EMERG "Caught Unhandled Exception, code = %08lx\n", (fp->seqstat & SEQSTAT_EXCAUSE)); CHK_DEBUGGER_TRAP(); break; } info.si_signo = sig; info.si_errno = 0; info.si_addr = (void *)fp->pc; force_sig_info(sig, &info, current); if (sig != 0 && sig != SIGTRAP) { unsigned long stack; dump_bfin_regs(fp, (void *)fp->retx); dump_bfin_trace_buffer(); show_stack(current, &stack); if (current->mm == NULL) panic("Kernel exception"); } /* if the address that we are about to return to is not valid, set it * to a valid address, if we have a current application or panic */ if (!(fp->pc <= physical_mem_end #if L1_CODE_LENGTH != 0 || (fp->pc >= L1_CODE_START && fp->pc <= (L1_CODE_START + L1_CODE_LENGTH)) #endif )) { if (current->mm) { fp->pc = current->mm->start_code; } else { printk(KERN_EMERG "I can't return to memory that doesn't exist" " - bad things happen\n"); panic("Help - I've fallen and can't get up\n"); } } trace_buffer_restore(j); return; } /* Typical exception handling routines */ #define EXPAND_LEN ((1 << CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN) * 256 - 1) void dump_bfin_trace_buffer(void) { #ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON int tflags, i = 0; #ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND int j, index; #endif trace_buffer_save(tflags); printk(KERN_EMERG "Hardware Trace:\n"); if (likely(bfin_read_TBUFSTAT() & TBUFCNT)) { for (; bfin_read_TBUFSTAT() & TBUFCNT; i++) { printk(KERN_EMERG "%4i Target : ", i); printk_address((unsigned long)bfin_read_TBUF()); printk("\n" KERN_EMERG " Source : "); printk_address((unsigned long)bfin_read_TBUF()); printk("\n"); } } #ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND if (trace_buff_offset) index = trace_buff_offset/4 - 1; else index = EXPAND_LEN; j = (1 << CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN) * 128; while (j) { printk(KERN_EMERG "%4i Target : ", i); printk_address(software_trace_buff[index]); index -= 1; if (index < 0 ) index = EXPAND_LEN; printk("\n" KERN_EMERG " Source : "); printk_address(software_trace_buff[index]); index -= 1; if (index < 0) index = EXPAND_LEN; printk("\n"); j--; i++; } #endif trace_buffer_restore(tflags); #endif } EXPORT_SYMBOL(dump_bfin_trace_buffer); static void show_trace(struct task_struct *tsk, unsigned long *sp) { unsigned long addr; printk("\nCall Trace:"); #ifdef CONFIG_KALLSYMS printk("\n"); #endif while (!kstack_end(sp)) { addr = *sp++; /* * If the address is either in the text segment of the * kernel, or in the region which contains vmalloc'ed * memory, it *may* be the address of a calling * routine; if so, print it so that someone tracing * down the cause of the crash will be able to figure * out the call path that was taken. */ if (kernel_text_address(addr)) print_ip_sym(addr); } printk("\n"); } void show_stack(struct task_struct *task, unsigned long *stack) { unsigned long *endstack, addr; int i; /* Cannot call dump_bfin_trace_buffer() here as show_stack() is * called externally in some places in the kernel. */ if (!stack) { if (task) stack = (unsigned long *)task->thread.ksp; else stack = (unsigned long *)&stack; } addr = (unsigned long)stack; endstack = (unsigned long *)PAGE_ALIGN(addr); printk(KERN_EMERG "Stack from %08lx:", (unsigned long)stack); for (i = 0; i < kstack_depth_to_print; i++) { if (stack + 1 > endstack) break; if (i % 8 == 0) printk("\n" KERN_EMERG " "); printk(" %08lx", *stack++); } show_trace(task, stack); } void dump_stack(void) { unsigned long stack; #ifdef CONFIG_DEBUG_BFIN_HWTRACE_ON int tflags; #endif trace_buffer_save(tflags); dump_bfin_trace_buffer(); show_stack(current, &stack); trace_buffer_restore(tflags); } EXPORT_SYMBOL(dump_stack); void dump_bfin_regs(struct pt_regs *fp, void *retaddr) { if (current->pid) { printk(KERN_EMERG "\n" KERN_EMERG "CURRENT PROCESS:\n" KERN_EMERG "\n"); printk(KERN_EMERG "COMM=%s PID=%d\n", current->comm, current->pid); } else { printk (KERN_EMERG "\n" KERN_EMERG "No Valid pid - Either things are really messed up," " or you are in the kernel\n"); } if (current->mm) { printk(KERN_EMERG "TEXT = 0x%p-0x%p DATA = 0x%p-0x%p\n" KERN_EMERG "BSS = 0x%p-0x%p USER-STACK = 0x%p\n" KERN_EMERG "\n", (void *)current->mm->start_code, (void *)current->mm->end_code, (void *)current->mm->start_data, (void *)current->mm->end_data, (void *)current->mm->end_data, (void *)current->mm->brk, (void *)current->mm->start_stack); } printk(KERN_EMERG "return address: [0x%p]; contents of:", retaddr); if (retaddr != 0 && retaddr <= (void *)physical_mem_end #if L1_CODE_LENGTH != 0 /* FIXME: Copy the code out of L1 Instruction SRAM through dma memcpy. */ && !(retaddr >= (void *)L1_CODE_START && retaddr < (void *)(L1_CODE_START + L1_CODE_LENGTH)) #endif ) { int i = ((unsigned int)retaddr & 0xFFFFFFF0) - 32; unsigned short x = 0; for (; i < ((unsigned int)retaddr & 0xFFFFFFF0) + 32; i += 2) { if (!(i & 0xF)) printk("\n" KERN_EMERG "0x%08x: ", i); if (get_user(x, (unsigned short *)i)) break; #ifndef CONFIG_DEBUG_HWERR /* If one of the last few instructions was a STI * it is likely that the error occured awhile ago * and we just noticed */ if (x >= 0x0040 && x <= 0x0047 && i <= 0) panic("\n\nWARNING : You should reconfigure" " the kernel to turn on\n" " 'Hardware error interrupt" " debugging'\n" " The rest of this error" " is meanless\n"); #endif if (i == (unsigned int)retaddr) printk("[%04x]", x); else printk(" %04x ", x); } printk("\n" KERN_EMERG "\n"); } else printk(KERN_EMERG "Cannot look at the [PC] for it is" "in unreadable L1 SRAM - sorry\n"); printk(KERN_EMERG "RETE: %08lx RETN: %08lx RETX: %08lx RETS: %08lx\n", fp->rete, fp->retn, fp->retx, fp->rets); printk(KERN_EMERG "IPEND: %04lx SYSCFG: %04lx\n", fp->ipend, fp->syscfg); printk(KERN_EMERG "SEQSTAT: %08lx SP: %08lx\n", (long)fp->seqstat, (long)fp); printk(KERN_EMERG "R0: %08lx R1: %08lx R2: %08lx R3: %08lx\n", fp->r0, fp->r1, fp->r2, fp->r3); printk(KERN_EMERG "R4: %08lx R5: %08lx R6: %08lx R7: %08lx\n", fp->r4, fp->r5, fp->r6, fp->r7); printk(KERN_EMERG "P0: %08lx P1: %08lx P2: %08lx P3: %08lx\n", fp->p0, fp->p1, fp->p2, fp->p3); printk(KERN_EMERG "P4: %08lx P5: %08lx FP: %08lx\n", fp->p4, fp->p5, fp->fp); printk(KERN_EMERG "A0.w: %08lx A0.x: %08lx A1.w: %08lx A1.x: %08lx\n", fp->a0w, fp->a0x, fp->a1w, fp->a1x); printk(KERN_EMERG "LB0: %08lx LT0: %08lx LC0: %08lx\n", fp->lb0, fp->lt0, fp->lc0); printk(KERN_EMERG "LB1: %08lx LT1: %08lx LC1: %08lx\n", fp->lb1, fp->lt1, fp->lc1); printk(KERN_EMERG "B0: %08lx L0: %08lx M0: %08lx I0: %08lx\n", fp->b0, fp->l0, fp->m0, fp->i0); printk(KERN_EMERG "B1: %08lx L1: %08lx M1: %08lx I1: %08lx\n", fp->b1, fp->l1, fp->m1, fp->i1); printk(KERN_EMERG "B2: %08lx L2: %08lx M2: %08lx I2: %08lx\n", fp->b2, fp->l2, fp->m2, fp->i2); printk(KERN_EMERG "B3: %08lx L3: %08lx M3: %08lx I3: %08lx\n", fp->b3, fp->l3, fp->m3, fp->i3); printk(KERN_EMERG "\n" KERN_EMERG "USP: %08lx ASTAT: %08lx\n", rdusp(), fp->astat); if ((long)fp->seqstat & SEQSTAT_EXCAUSE) { printk(KERN_EMERG "DCPLB_FAULT_ADDR=%p\n", (void *)bfin_read_DCPLB_FAULT_ADDR()); printk(KERN_EMERG "ICPLB_FAULT_ADDR=%p\n", (void *)bfin_read_ICPLB_FAULT_ADDR()); } printk("\n\n"); } #ifdef CONFIG_SYS_BFIN_SPINLOCK_L1 asmlinkage int sys_bfin_spinlock(int *spinlock)__attribute__((l1_text)); #endif asmlinkage int sys_bfin_spinlock(int *spinlock) { int ret = 0; int tmp = 0; local_irq_disable(); ret = get_user(tmp, spinlock); if (ret == 0) { if (tmp) ret = 1; tmp = 1; put_user(tmp, spinlock); } local_irq_enable(); return ret; } int bfin_request_exception(unsigned int exception, void (*handler)(void)) { void (*curr_handler)(void); if (exception > 0x3F) return -EINVAL; curr_handler = ex_table[exception]; if (curr_handler != ex_replaceable) return -EBUSY; ex_table[exception] = handler; return 0; } EXPORT_SYMBOL(bfin_request_exception); int bfin_free_exception(unsigned int exception, void (*handler)(void)) { void (*curr_handler)(void); if (exception > 0x3F) return -EINVAL; curr_handler = ex_table[exception]; if (curr_handler != handler) return -EBUSY; ex_table[exception] = ex_replaceable; return 0; } EXPORT_SYMBOL(bfin_free_exception); void panic_cplb_error(int cplb_panic, struct pt_regs *fp) { switch (cplb_panic) { case CPLB_NO_UNLOCKED: printk(KERN_EMERG "All CPLBs are locked\n"); break; case CPLB_PROT_VIOL: return; case CPLB_NO_ADDR_MATCH: return; case CPLB_UNKNOWN_ERR: printk(KERN_EMERG "Unknown CPLB Exception\n"); break; } printk(KERN_EMERG "DCPLB_FAULT_ADDR=%p\n", (void *)bfin_read_DCPLB_FAULT_ADDR()); printk(KERN_EMERG "ICPLB_FAULT_ADDR=%p\n", (void *)bfin_read_ICPLB_FAULT_ADDR()); dump_bfin_regs(fp, (void *)fp->retx); dump_stack(); panic("Unrecoverable event\n"); }