/*
* 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 <asm/uaccess.h>
#include <asm/traps.h>
#include <asm/cacheflush.h>
#include <asm/blackfin.h>
#include <asm/uaccess.h>
#include <asm/irq_handler.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/kallsyms.h>
#ifdef CONFIG_KGDB
# include <linux/debugger.h>
# include <linux/kgdb.h>
#endif
/* Initiate the event table handler */
void __init trap_init(void)
{
CSYNC();
bfin_write_EVT3(trap);
CSYNC();
}
asmlinkage void trap_c(struct pt_regs *fp);
int kstack_depth_to_print = 48;
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);
}
#define trace_buffer_save(x) \
do { \
(x) = bfin_read_TBUFCTL(); \
bfin_write_TBUFCTL((x) & ~TBUFEN); \
} while (0)
#define trace_buffer_restore(x) \
do { \
bfin_write_TBUFCTL((x)); \
} while (0)
asmlinkage void trap_c(struct pt_regs *fp)
{
int j, 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 - Atomic test and set */
case VEC_EXCPT03:
info.si_code = SEGV_STACKFLOW;
sig = SIGSEGV;
printk(KERN_EMERG EXC_0x03);
CHK_DEBUGGER_TRAP();
break;
/* 0x04 - spinlock - handled by _ex_spinlock,
getting here is an error */
/* 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 */
void dump_bfin_trace_buffer(void)
{
int tflags;
trace_buffer_save(tflags);
if (likely(bfin_read_TBUFSTAT() & TBUFCNT)) {
int i;
printk(KERN_EMERG "Hardware Trace:\n");
for (i = 0; bfin_read_TBUFSTAT() & TBUFCNT; i++) {
printk(KERN_EMERG "%2i Target : ", i);
printk_address((unsigned long)bfin_read_TBUF());
printk("\n" KERN_EMERG " Source : ");
printk_address((unsigned long)bfin_read_TBUF());
printk("\n");
}
}
trace_buffer_restore(tflags);
}
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;
int tflags;
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(KERN_EMERG "\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;
}
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");
}
