926 lines
21 KiB
C
926 lines
21 KiB
C
/*
|
|
* 'traps.c' handles hardware traps and faults after we have saved some
|
|
* state in 'entry.S'.
|
|
*
|
|
* SuperH version: Copyright (C) 1999 Niibe Yutaka
|
|
* Copyright (C) 2000 Philipp Rumpf
|
|
* Copyright (C) 2000 David Howells
|
|
* Copyright (C) 2002 - 2010 Paul Mundt
|
|
*
|
|
* This file is subject to the terms and conditions of the GNU General Public
|
|
* License. See the file "COPYING" in the main directory of this archive
|
|
* for more details.
|
|
*/
|
|
#include <linux/kernel.h>
|
|
#include <linux/ptrace.h>
|
|
#include <linux/hardirq.h>
|
|
#include <linux/init.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/module.h>
|
|
#include <linux/kallsyms.h>
|
|
#include <linux/io.h>
|
|
#include <linux/bug.h>
|
|
#include <linux/debug_locks.h>
|
|
#include <linux/kdebug.h>
|
|
#include <linux/kexec.h>
|
|
#include <linux/limits.h>
|
|
#include <linux/sysfs.h>
|
|
#include <linux/uaccess.h>
|
|
#include <linux/perf_event.h>
|
|
#include <asm/alignment.h>
|
|
#include <asm/fpu.h>
|
|
#include <asm/kprobes.h>
|
|
#include <asm/traps.h>
|
|
#include <asm/bl_bit.h>
|
|
|
|
#ifdef CONFIG_CPU_SH2
|
|
# define TRAP_RESERVED_INST 4
|
|
# define TRAP_ILLEGAL_SLOT_INST 6
|
|
# define TRAP_ADDRESS_ERROR 9
|
|
# ifdef CONFIG_CPU_SH2A
|
|
# define TRAP_UBC 12
|
|
# define TRAP_FPU_ERROR 13
|
|
# define TRAP_DIVZERO_ERROR 17
|
|
# define TRAP_DIVOVF_ERROR 18
|
|
# endif
|
|
#else
|
|
#define TRAP_RESERVED_INST 12
|
|
#define TRAP_ILLEGAL_SLOT_INST 13
|
|
#endif
|
|
|
|
static void dump_mem(const char *str, unsigned long bottom, unsigned long top)
|
|
{
|
|
unsigned long p;
|
|
int i;
|
|
|
|
printk("%s(0x%08lx to 0x%08lx)\n", str, bottom, top);
|
|
|
|
for (p = bottom & ~31; p < top; ) {
|
|
printk("%04lx: ", p & 0xffff);
|
|
|
|
for (i = 0; i < 8; i++, p += 4) {
|
|
unsigned int val;
|
|
|
|
if (p < bottom || p >= top)
|
|
printk(" ");
|
|
else {
|
|
if (__get_user(val, (unsigned int __user *)p)) {
|
|
printk("\n");
|
|
return;
|
|
}
|
|
printk("%08x ", val);
|
|
}
|
|
}
|
|
printk("\n");
|
|
}
|
|
}
|
|
|
|
static DEFINE_SPINLOCK(die_lock);
|
|
|
|
void die(const char * str, struct pt_regs * regs, long err)
|
|
{
|
|
static int die_counter;
|
|
|
|
oops_enter();
|
|
|
|
spin_lock_irq(&die_lock);
|
|
console_verbose();
|
|
bust_spinlocks(1);
|
|
|
|
printk("%s: %04lx [#%d]\n", str, err & 0xffff, ++die_counter);
|
|
print_modules();
|
|
show_regs(regs);
|
|
|
|
printk("Process: %s (pid: %d, stack limit = %p)\n", current->comm,
|
|
task_pid_nr(current), task_stack_page(current) + 1);
|
|
|
|
if (!user_mode(regs) || in_interrupt())
|
|
dump_mem("Stack: ", regs->regs[15], THREAD_SIZE +
|
|
(unsigned long)task_stack_page(current));
|
|
|
|
notify_die(DIE_OOPS, str, regs, err, 255, SIGSEGV);
|
|
|
|
bust_spinlocks(0);
|
|
add_taint(TAINT_DIE);
|
|
spin_unlock_irq(&die_lock);
|
|
oops_exit();
|
|
|
|
if (kexec_should_crash(current))
|
|
crash_kexec(regs);
|
|
|
|
if (in_interrupt())
|
|
panic("Fatal exception in interrupt");
|
|
|
|
if (panic_on_oops)
|
|
panic("Fatal exception");
|
|
|
|
do_exit(SIGSEGV);
|
|
}
|
|
|
|
static inline void die_if_kernel(const char *str, struct pt_regs *regs,
|
|
long err)
|
|
{
|
|
if (!user_mode(regs))
|
|
die(str, regs, err);
|
|
}
|
|
|
|
/*
|
|
* try and fix up kernelspace address errors
|
|
* - userspace errors just cause EFAULT to be returned, resulting in SEGV
|
|
* - kernel/userspace interfaces cause a jump to an appropriate handler
|
|
* - other kernel errors are bad
|
|
*/
|
|
static void die_if_no_fixup(const char * str, struct pt_regs * regs, long err)
|
|
{
|
|
if (!user_mode(regs)) {
|
|
const struct exception_table_entry *fixup;
|
|
fixup = search_exception_tables(regs->pc);
|
|
if (fixup) {
|
|
regs->pc = fixup->fixup;
|
|
return;
|
|
}
|
|
|
|
die(str, regs, err);
|
|
}
|
|
}
|
|
|
|
static inline void sign_extend(unsigned int count, unsigned char *dst)
|
|
{
|
|
#ifdef __LITTLE_ENDIAN__
|
|
if ((count == 1) && dst[0] & 0x80) {
|
|
dst[1] = 0xff;
|
|
dst[2] = 0xff;
|
|
dst[3] = 0xff;
|
|
}
|
|
if ((count == 2) && dst[1] & 0x80) {
|
|
dst[2] = 0xff;
|
|
dst[3] = 0xff;
|
|
}
|
|
#else
|
|
if ((count == 1) && dst[3] & 0x80) {
|
|
dst[2] = 0xff;
|
|
dst[1] = 0xff;
|
|
dst[0] = 0xff;
|
|
}
|
|
if ((count == 2) && dst[2] & 0x80) {
|
|
dst[1] = 0xff;
|
|
dst[0] = 0xff;
|
|
}
|
|
#endif
|
|
}
|
|
|
|
static struct mem_access user_mem_access = {
|
|
copy_from_user,
|
|
copy_to_user,
|
|
};
|
|
|
|
/*
|
|
* handle an instruction that does an unaligned memory access by emulating the
|
|
* desired behaviour
|
|
* - note that PC _may not_ point to the faulting instruction
|
|
* (if that instruction is in a branch delay slot)
|
|
* - return 0 if emulation okay, -EFAULT on existential error
|
|
*/
|
|
static int handle_unaligned_ins(insn_size_t instruction, struct pt_regs *regs,
|
|
struct mem_access *ma)
|
|
{
|
|
int ret, index, count;
|
|
unsigned long *rm, *rn;
|
|
unsigned char *src, *dst;
|
|
unsigned char __user *srcu, *dstu;
|
|
|
|
index = (instruction>>8)&15; /* 0x0F00 */
|
|
rn = ®s->regs[index];
|
|
|
|
index = (instruction>>4)&15; /* 0x00F0 */
|
|
rm = ®s->regs[index];
|
|
|
|
count = 1<<(instruction&3);
|
|
|
|
switch (count) {
|
|
case 1: inc_unaligned_byte_access(); break;
|
|
case 2: inc_unaligned_word_access(); break;
|
|
case 4: inc_unaligned_dword_access(); break;
|
|
case 8: inc_unaligned_multi_access(); break;
|
|
}
|
|
|
|
ret = -EFAULT;
|
|
switch (instruction>>12) {
|
|
case 0: /* mov.[bwl] to/from memory via r0+rn */
|
|
if (instruction & 8) {
|
|
/* from memory */
|
|
srcu = (unsigned char __user *)*rm;
|
|
srcu += regs->regs[0];
|
|
dst = (unsigned char *)rn;
|
|
*(unsigned long *)dst = 0;
|
|
|
|
#if !defined(__LITTLE_ENDIAN__)
|
|
dst += 4-count;
|
|
#endif
|
|
if (ma->from(dst, srcu, count))
|
|
goto fetch_fault;
|
|
|
|
sign_extend(count, dst);
|
|
} else {
|
|
/* to memory */
|
|
src = (unsigned char *)rm;
|
|
#if !defined(__LITTLE_ENDIAN__)
|
|
src += 4-count;
|
|
#endif
|
|
dstu = (unsigned char __user *)*rn;
|
|
dstu += regs->regs[0];
|
|
|
|
if (ma->to(dstu, src, count))
|
|
goto fetch_fault;
|
|
}
|
|
ret = 0;
|
|
break;
|
|
|
|
case 1: /* mov.l Rm,@(disp,Rn) */
|
|
src = (unsigned char*) rm;
|
|
dstu = (unsigned char __user *)*rn;
|
|
dstu += (instruction&0x000F)<<2;
|
|
|
|
if (ma->to(dstu, src, 4))
|
|
goto fetch_fault;
|
|
ret = 0;
|
|
break;
|
|
|
|
case 2: /* mov.[bwl] to memory, possibly with pre-decrement */
|
|
if (instruction & 4)
|
|
*rn -= count;
|
|
src = (unsigned char*) rm;
|
|
dstu = (unsigned char __user *)*rn;
|
|
#if !defined(__LITTLE_ENDIAN__)
|
|
src += 4-count;
|
|
#endif
|
|
if (ma->to(dstu, src, count))
|
|
goto fetch_fault;
|
|
ret = 0;
|
|
break;
|
|
|
|
case 5: /* mov.l @(disp,Rm),Rn */
|
|
srcu = (unsigned char __user *)*rm;
|
|
srcu += (instruction & 0x000F) << 2;
|
|
dst = (unsigned char *)rn;
|
|
*(unsigned long *)dst = 0;
|
|
|
|
if (ma->from(dst, srcu, 4))
|
|
goto fetch_fault;
|
|
ret = 0;
|
|
break;
|
|
|
|
case 6: /* mov.[bwl] from memory, possibly with post-increment */
|
|
srcu = (unsigned char __user *)*rm;
|
|
if (instruction & 4)
|
|
*rm += count;
|
|
dst = (unsigned char*) rn;
|
|
*(unsigned long*)dst = 0;
|
|
|
|
#if !defined(__LITTLE_ENDIAN__)
|
|
dst += 4-count;
|
|
#endif
|
|
if (ma->from(dst, srcu, count))
|
|
goto fetch_fault;
|
|
sign_extend(count, dst);
|
|
ret = 0;
|
|
break;
|
|
|
|
case 8:
|
|
switch ((instruction&0xFF00)>>8) {
|
|
case 0x81: /* mov.w R0,@(disp,Rn) */
|
|
src = (unsigned char *) ®s->regs[0];
|
|
#if !defined(__LITTLE_ENDIAN__)
|
|
src += 2;
|
|
#endif
|
|
dstu = (unsigned char __user *)*rm; /* called Rn in the spec */
|
|
dstu += (instruction & 0x000F) << 1;
|
|
|
|
if (ma->to(dstu, src, 2))
|
|
goto fetch_fault;
|
|
ret = 0;
|
|
break;
|
|
|
|
case 0x85: /* mov.w @(disp,Rm),R0 */
|
|
srcu = (unsigned char __user *)*rm;
|
|
srcu += (instruction & 0x000F) << 1;
|
|
dst = (unsigned char *) ®s->regs[0];
|
|
*(unsigned long *)dst = 0;
|
|
|
|
#if !defined(__LITTLE_ENDIAN__)
|
|
dst += 2;
|
|
#endif
|
|
if (ma->from(dst, srcu, 2))
|
|
goto fetch_fault;
|
|
sign_extend(2, dst);
|
|
ret = 0;
|
|
break;
|
|
}
|
|
break;
|
|
|
|
case 9: /* mov.w @(disp,PC),Rn */
|
|
srcu = (unsigned char __user *)regs->pc;
|
|
srcu += 4;
|
|
srcu += (instruction & 0x00FF) << 1;
|
|
dst = (unsigned char *)rn;
|
|
*(unsigned long *)dst = 0;
|
|
|
|
#if !defined(__LITTLE_ENDIAN__)
|
|
dst += 2;
|
|
#endif
|
|
|
|
if (ma->from(dst, srcu, 2))
|
|
goto fetch_fault;
|
|
sign_extend(2, dst);
|
|
ret = 0;
|
|
break;
|
|
|
|
case 0xd: /* mov.l @(disp,PC),Rn */
|
|
srcu = (unsigned char __user *)(regs->pc & ~0x3);
|
|
srcu += 4;
|
|
srcu += (instruction & 0x00FF) << 2;
|
|
dst = (unsigned char *)rn;
|
|
*(unsigned long *)dst = 0;
|
|
|
|
if (ma->from(dst, srcu, 4))
|
|
goto fetch_fault;
|
|
ret = 0;
|
|
break;
|
|
}
|
|
return ret;
|
|
|
|
fetch_fault:
|
|
/* Argh. Address not only misaligned but also non-existent.
|
|
* Raise an EFAULT and see if it's trapped
|
|
*/
|
|
die_if_no_fixup("Fault in unaligned fixup", regs, 0);
|
|
return -EFAULT;
|
|
}
|
|
|
|
/*
|
|
* emulate the instruction in the delay slot
|
|
* - fetches the instruction from PC+2
|
|
*/
|
|
static inline int handle_delayslot(struct pt_regs *regs,
|
|
insn_size_t old_instruction,
|
|
struct mem_access *ma)
|
|
{
|
|
insn_size_t instruction;
|
|
void __user *addr = (void __user *)(regs->pc +
|
|
instruction_size(old_instruction));
|
|
|
|
if (copy_from_user(&instruction, addr, sizeof(instruction))) {
|
|
/* the instruction-fetch faulted */
|
|
if (user_mode(regs))
|
|
return -EFAULT;
|
|
|
|
/* kernel */
|
|
die("delay-slot-insn faulting in handle_unaligned_delayslot",
|
|
regs, 0);
|
|
}
|
|
|
|
return handle_unaligned_ins(instruction, regs, ma);
|
|
}
|
|
|
|
/*
|
|
* handle an instruction that does an unaligned memory access
|
|
* - have to be careful of branch delay-slot instructions that fault
|
|
* SH3:
|
|
* - if the branch would be taken PC points to the branch
|
|
* - if the branch would not be taken, PC points to delay-slot
|
|
* SH4:
|
|
* - PC always points to delayed branch
|
|
* - return 0 if handled, -EFAULT if failed (may not return if in kernel)
|
|
*/
|
|
|
|
/* Macros to determine offset from current PC for branch instructions */
|
|
/* Explicit type coercion is used to force sign extension where needed */
|
|
#define SH_PC_8BIT_OFFSET(instr) ((((signed char)(instr))*2) + 4)
|
|
#define SH_PC_12BIT_OFFSET(instr) ((((signed short)(instr<<4))>>3) + 4)
|
|
|
|
int handle_unaligned_access(insn_size_t instruction, struct pt_regs *regs,
|
|
struct mem_access *ma, int expected,
|
|
unsigned long address)
|
|
{
|
|
u_int rm;
|
|
int ret, index;
|
|
|
|
/*
|
|
* XXX: We can't handle mixed 16/32-bit instructions yet
|
|
*/
|
|
if (instruction_size(instruction) != 2)
|
|
return -EINVAL;
|
|
|
|
index = (instruction>>8)&15; /* 0x0F00 */
|
|
rm = regs->regs[index];
|
|
|
|
/*
|
|
* Log the unexpected fixups, and then pass them on to perf.
|
|
*
|
|
* We intentionally don't report the expected cases to perf as
|
|
* otherwise the trapped I/O case will skew the results too much
|
|
* to be useful.
|
|
*/
|
|
if (!expected) {
|
|
unaligned_fixups_notify(current, instruction, regs);
|
|
perf_sw_event(PERF_COUNT_SW_ALIGNMENT_FAULTS, 1,
|
|
regs, address);
|
|
}
|
|
|
|
ret = -EFAULT;
|
|
switch (instruction&0xF000) {
|
|
case 0x0000:
|
|
if (instruction==0x000B) {
|
|
/* rts */
|
|
ret = handle_delayslot(regs, instruction, ma);
|
|
if (ret==0)
|
|
regs->pc = regs->pr;
|
|
}
|
|
else if ((instruction&0x00FF)==0x0023) {
|
|
/* braf @Rm */
|
|
ret = handle_delayslot(regs, instruction, ma);
|
|
if (ret==0)
|
|
regs->pc += rm + 4;
|
|
}
|
|
else if ((instruction&0x00FF)==0x0003) {
|
|
/* bsrf @Rm */
|
|
ret = handle_delayslot(regs, instruction, ma);
|
|
if (ret==0) {
|
|
regs->pr = regs->pc + 4;
|
|
regs->pc += rm + 4;
|
|
}
|
|
}
|
|
else {
|
|
/* mov.[bwl] to/from memory via r0+rn */
|
|
goto simple;
|
|
}
|
|
break;
|
|
|
|
case 0x1000: /* mov.l Rm,@(disp,Rn) */
|
|
goto simple;
|
|
|
|
case 0x2000: /* mov.[bwl] to memory, possibly with pre-decrement */
|
|
goto simple;
|
|
|
|
case 0x4000:
|
|
if ((instruction&0x00FF)==0x002B) {
|
|
/* jmp @Rm */
|
|
ret = handle_delayslot(regs, instruction, ma);
|
|
if (ret==0)
|
|
regs->pc = rm;
|
|
}
|
|
else if ((instruction&0x00FF)==0x000B) {
|
|
/* jsr @Rm */
|
|
ret = handle_delayslot(regs, instruction, ma);
|
|
if (ret==0) {
|
|
regs->pr = regs->pc + 4;
|
|
regs->pc = rm;
|
|
}
|
|
}
|
|
else {
|
|
/* mov.[bwl] to/from memory via r0+rn */
|
|
goto simple;
|
|
}
|
|
break;
|
|
|
|
case 0x5000: /* mov.l @(disp,Rm),Rn */
|
|
goto simple;
|
|
|
|
case 0x6000: /* mov.[bwl] from memory, possibly with post-increment */
|
|
goto simple;
|
|
|
|
case 0x8000: /* bf lab, bf/s lab, bt lab, bt/s lab */
|
|
switch (instruction&0x0F00) {
|
|
case 0x0100: /* mov.w R0,@(disp,Rm) */
|
|
goto simple;
|
|
case 0x0500: /* mov.w @(disp,Rm),R0 */
|
|
goto simple;
|
|
case 0x0B00: /* bf lab - no delayslot*/
|
|
ret = 0;
|
|
break;
|
|
case 0x0F00: /* bf/s lab */
|
|
ret = handle_delayslot(regs, instruction, ma);
|
|
if (ret==0) {
|
|
#if defined(CONFIG_CPU_SH4) || defined(CONFIG_SH7705_CACHE_32KB)
|
|
if ((regs->sr & 0x00000001) != 0)
|
|
regs->pc += 4; /* next after slot */
|
|
else
|
|
#endif
|
|
regs->pc += SH_PC_8BIT_OFFSET(instruction);
|
|
}
|
|
break;
|
|
case 0x0900: /* bt lab - no delayslot */
|
|
ret = 0;
|
|
break;
|
|
case 0x0D00: /* bt/s lab */
|
|
ret = handle_delayslot(regs, instruction, ma);
|
|
if (ret==0) {
|
|
#if defined(CONFIG_CPU_SH4) || defined(CONFIG_SH7705_CACHE_32KB)
|
|
if ((regs->sr & 0x00000001) == 0)
|
|
regs->pc += 4; /* next after slot */
|
|
else
|
|
#endif
|
|
regs->pc += SH_PC_8BIT_OFFSET(instruction);
|
|
}
|
|
break;
|
|
}
|
|
break;
|
|
|
|
case 0x9000: /* mov.w @(disp,Rm),Rn */
|
|
goto simple;
|
|
|
|
case 0xA000: /* bra label */
|
|
ret = handle_delayslot(regs, instruction, ma);
|
|
if (ret==0)
|
|
regs->pc += SH_PC_12BIT_OFFSET(instruction);
|
|
break;
|
|
|
|
case 0xB000: /* bsr label */
|
|
ret = handle_delayslot(regs, instruction, ma);
|
|
if (ret==0) {
|
|
regs->pr = regs->pc + 4;
|
|
regs->pc += SH_PC_12BIT_OFFSET(instruction);
|
|
}
|
|
break;
|
|
|
|
case 0xD000: /* mov.l @(disp,Rm),Rn */
|
|
goto simple;
|
|
}
|
|
return ret;
|
|
|
|
/* handle non-delay-slot instruction */
|
|
simple:
|
|
ret = handle_unaligned_ins(instruction, regs, ma);
|
|
if (ret==0)
|
|
regs->pc += instruction_size(instruction);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Handle various address error exceptions:
|
|
* - instruction address error:
|
|
* misaligned PC
|
|
* PC >= 0x80000000 in user mode
|
|
* - data address error (read and write)
|
|
* misaligned data access
|
|
* access to >= 0x80000000 is user mode
|
|
* Unfortuntaly we can't distinguish between instruction address error
|
|
* and data address errors caused by read accesses.
|
|
*/
|
|
asmlinkage void do_address_error(struct pt_regs *regs,
|
|
unsigned long writeaccess,
|
|
unsigned long address)
|
|
{
|
|
unsigned long error_code = 0;
|
|
mm_segment_t oldfs;
|
|
siginfo_t info;
|
|
insn_size_t instruction;
|
|
int tmp;
|
|
|
|
/* Intentional ifdef */
|
|
#ifdef CONFIG_CPU_HAS_SR_RB
|
|
error_code = lookup_exception_vector();
|
|
#endif
|
|
|
|
oldfs = get_fs();
|
|
|
|
if (user_mode(regs)) {
|
|
int si_code = BUS_ADRERR;
|
|
unsigned int user_action;
|
|
|
|
local_irq_enable();
|
|
inc_unaligned_user_access();
|
|
|
|
set_fs(USER_DS);
|
|
if (copy_from_user(&instruction, (insn_size_t *)(regs->pc & ~1),
|
|
sizeof(instruction))) {
|
|
set_fs(oldfs);
|
|
goto uspace_segv;
|
|
}
|
|
set_fs(oldfs);
|
|
|
|
/* shout about userspace fixups */
|
|
unaligned_fixups_notify(current, instruction, regs);
|
|
|
|
user_action = unaligned_user_action();
|
|
if (user_action & UM_FIXUP)
|
|
goto fixup;
|
|
if (user_action & UM_SIGNAL)
|
|
goto uspace_segv;
|
|
else {
|
|
/* ignore */
|
|
regs->pc += instruction_size(instruction);
|
|
return;
|
|
}
|
|
|
|
fixup:
|
|
/* bad PC is not something we can fix */
|
|
if (regs->pc & 1) {
|
|
si_code = BUS_ADRALN;
|
|
goto uspace_segv;
|
|
}
|
|
|
|
set_fs(USER_DS);
|
|
tmp = handle_unaligned_access(instruction, regs,
|
|
&user_mem_access, 0,
|
|
address);
|
|
set_fs(oldfs);
|
|
|
|
if (tmp == 0)
|
|
return; /* sorted */
|
|
uspace_segv:
|
|
printk(KERN_NOTICE "Sending SIGBUS to \"%s\" due to unaligned "
|
|
"access (PC %lx PR %lx)\n", current->comm, regs->pc,
|
|
regs->pr);
|
|
|
|
info.si_signo = SIGBUS;
|
|
info.si_errno = 0;
|
|
info.si_code = si_code;
|
|
info.si_addr = (void __user *)address;
|
|
force_sig_info(SIGBUS, &info, current);
|
|
} else {
|
|
inc_unaligned_kernel_access();
|
|
|
|
if (regs->pc & 1)
|
|
die("unaligned program counter", regs, error_code);
|
|
|
|
set_fs(KERNEL_DS);
|
|
if (copy_from_user(&instruction, (void __user *)(regs->pc),
|
|
sizeof(instruction))) {
|
|
/* Argh. Fault on the instruction itself.
|
|
This should never happen non-SMP
|
|
*/
|
|
set_fs(oldfs);
|
|
die("insn faulting in do_address_error", regs, 0);
|
|
}
|
|
|
|
unaligned_fixups_notify(current, instruction, regs);
|
|
|
|
handle_unaligned_access(instruction, regs, &user_mem_access,
|
|
0, address);
|
|
set_fs(oldfs);
|
|
}
|
|
}
|
|
|
|
#ifdef CONFIG_SH_DSP
|
|
/*
|
|
* SH-DSP support gerg@snapgear.com.
|
|
*/
|
|
int is_dsp_inst(struct pt_regs *regs)
|
|
{
|
|
unsigned short inst = 0;
|
|
|
|
/*
|
|
* Safe guard if DSP mode is already enabled or we're lacking
|
|
* the DSP altogether.
|
|
*/
|
|
if (!(current_cpu_data.flags & CPU_HAS_DSP) || (regs->sr & SR_DSP))
|
|
return 0;
|
|
|
|
get_user(inst, ((unsigned short *) regs->pc));
|
|
|
|
inst &= 0xf000;
|
|
|
|
/* Check for any type of DSP or support instruction */
|
|
if ((inst == 0xf000) || (inst == 0x4000))
|
|
return 1;
|
|
|
|
return 0;
|
|
}
|
|
#else
|
|
#define is_dsp_inst(regs) (0)
|
|
#endif /* CONFIG_SH_DSP */
|
|
|
|
#ifdef CONFIG_CPU_SH2A
|
|
asmlinkage void do_divide_error(unsigned long r4, unsigned long r5,
|
|
unsigned long r6, unsigned long r7,
|
|
struct pt_regs __regs)
|
|
{
|
|
siginfo_t info;
|
|
|
|
switch (r4) {
|
|
case TRAP_DIVZERO_ERROR:
|
|
info.si_code = FPE_INTDIV;
|
|
break;
|
|
case TRAP_DIVOVF_ERROR:
|
|
info.si_code = FPE_INTOVF;
|
|
break;
|
|
}
|
|
|
|
force_sig_info(SIGFPE, &info, current);
|
|
}
|
|
#endif
|
|
|
|
asmlinkage void do_reserved_inst(unsigned long r4, unsigned long r5,
|
|
unsigned long r6, unsigned long r7,
|
|
struct pt_regs __regs)
|
|
{
|
|
struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
|
|
unsigned long error_code;
|
|
struct task_struct *tsk = current;
|
|
|
|
#ifdef CONFIG_SH_FPU_EMU
|
|
unsigned short inst = 0;
|
|
int err;
|
|
|
|
get_user(inst, (unsigned short*)regs->pc);
|
|
|
|
err = do_fpu_inst(inst, regs);
|
|
if (!err) {
|
|
regs->pc += instruction_size(inst);
|
|
return;
|
|
}
|
|
/* not a FPU inst. */
|
|
#endif
|
|
|
|
#ifdef CONFIG_SH_DSP
|
|
/* Check if it's a DSP instruction */
|
|
if (is_dsp_inst(regs)) {
|
|
/* Enable DSP mode, and restart instruction. */
|
|
regs->sr |= SR_DSP;
|
|
/* Save DSP mode */
|
|
tsk->thread.dsp_status.status |= SR_DSP;
|
|
return;
|
|
}
|
|
#endif
|
|
|
|
error_code = lookup_exception_vector();
|
|
|
|
local_irq_enable();
|
|
force_sig(SIGILL, tsk);
|
|
die_if_no_fixup("reserved instruction", regs, error_code);
|
|
}
|
|
|
|
#ifdef CONFIG_SH_FPU_EMU
|
|
static int emulate_branch(unsigned short inst, struct pt_regs *regs)
|
|
{
|
|
/*
|
|
* bfs: 8fxx: PC+=d*2+4;
|
|
* bts: 8dxx: PC+=d*2+4;
|
|
* bra: axxx: PC+=D*2+4;
|
|
* bsr: bxxx: PC+=D*2+4 after PR=PC+4;
|
|
* braf:0x23: PC+=Rn*2+4;
|
|
* bsrf:0x03: PC+=Rn*2+4 after PR=PC+4;
|
|
* jmp: 4x2b: PC=Rn;
|
|
* jsr: 4x0b: PC=Rn after PR=PC+4;
|
|
* rts: 000b: PC=PR;
|
|
*/
|
|
if (((inst & 0xf000) == 0xb000) || /* bsr */
|
|
((inst & 0xf0ff) == 0x0003) || /* bsrf */
|
|
((inst & 0xf0ff) == 0x400b)) /* jsr */
|
|
regs->pr = regs->pc + 4;
|
|
|
|
if ((inst & 0xfd00) == 0x8d00) { /* bfs, bts */
|
|
regs->pc += SH_PC_8BIT_OFFSET(inst);
|
|
return 0;
|
|
}
|
|
|
|
if ((inst & 0xe000) == 0xa000) { /* bra, bsr */
|
|
regs->pc += SH_PC_12BIT_OFFSET(inst);
|
|
return 0;
|
|
}
|
|
|
|
if ((inst & 0xf0df) == 0x0003) { /* braf, bsrf */
|
|
regs->pc += regs->regs[(inst & 0x0f00) >> 8] + 4;
|
|
return 0;
|
|
}
|
|
|
|
if ((inst & 0xf0df) == 0x400b) { /* jmp, jsr */
|
|
regs->pc = regs->regs[(inst & 0x0f00) >> 8];
|
|
return 0;
|
|
}
|
|
|
|
if ((inst & 0xffff) == 0x000b) { /* rts */
|
|
regs->pc = regs->pr;
|
|
return 0;
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
#endif
|
|
|
|
asmlinkage void do_illegal_slot_inst(unsigned long r4, unsigned long r5,
|
|
unsigned long r6, unsigned long r7,
|
|
struct pt_regs __regs)
|
|
{
|
|
struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
|
|
unsigned long inst;
|
|
struct task_struct *tsk = current;
|
|
|
|
if (kprobe_handle_illslot(regs->pc) == 0)
|
|
return;
|
|
|
|
#ifdef CONFIG_SH_FPU_EMU
|
|
get_user(inst, (unsigned short *)regs->pc + 1);
|
|
if (!do_fpu_inst(inst, regs)) {
|
|
get_user(inst, (unsigned short *)regs->pc);
|
|
if (!emulate_branch(inst, regs))
|
|
return;
|
|
/* fault in branch.*/
|
|
}
|
|
/* not a FPU inst. */
|
|
#endif
|
|
|
|
inst = lookup_exception_vector();
|
|
|
|
local_irq_enable();
|
|
force_sig(SIGILL, tsk);
|
|
die_if_no_fixup("illegal slot instruction", regs, inst);
|
|
}
|
|
|
|
asmlinkage void do_exception_error(unsigned long r4, unsigned long r5,
|
|
unsigned long r6, unsigned long r7,
|
|
struct pt_regs __regs)
|
|
{
|
|
struct pt_regs *regs = RELOC_HIDE(&__regs, 0);
|
|
long ex;
|
|
|
|
ex = lookup_exception_vector();
|
|
die_if_kernel("exception", regs, ex);
|
|
}
|
|
|
|
void __cpuinit per_cpu_trap_init(void)
|
|
{
|
|
extern void *vbr_base;
|
|
|
|
/* NOTE: The VBR value should be at P1
|
|
(or P2, virtural "fixed" address space).
|
|
It's definitely should not in physical address. */
|
|
|
|
asm volatile("ldc %0, vbr"
|
|
: /* no output */
|
|
: "r" (&vbr_base)
|
|
: "memory");
|
|
|
|
/* disable exception blocking now when the vbr has been setup */
|
|
clear_bl_bit();
|
|
}
|
|
|
|
void *set_exception_table_vec(unsigned int vec, void *handler)
|
|
{
|
|
extern void *exception_handling_table[];
|
|
void *old_handler;
|
|
|
|
old_handler = exception_handling_table[vec];
|
|
exception_handling_table[vec] = handler;
|
|
return old_handler;
|
|
}
|
|
|
|
void __init trap_init(void)
|
|
{
|
|
set_exception_table_vec(TRAP_RESERVED_INST, do_reserved_inst);
|
|
set_exception_table_vec(TRAP_ILLEGAL_SLOT_INST, do_illegal_slot_inst);
|
|
|
|
#if defined(CONFIG_CPU_SH4) && !defined(CONFIG_SH_FPU) || \
|
|
defined(CONFIG_SH_FPU_EMU)
|
|
/*
|
|
* For SH-4 lacking an FPU, treat floating point instructions as
|
|
* reserved. They'll be handled in the math-emu case, or faulted on
|
|
* otherwise.
|
|
*/
|
|
set_exception_table_evt(0x800, do_reserved_inst);
|
|
set_exception_table_evt(0x820, do_illegal_slot_inst);
|
|
#elif defined(CONFIG_SH_FPU)
|
|
set_exception_table_evt(0x800, fpu_state_restore_trap_handler);
|
|
set_exception_table_evt(0x820, fpu_state_restore_trap_handler);
|
|
#endif
|
|
|
|
#ifdef CONFIG_CPU_SH2
|
|
set_exception_table_vec(TRAP_ADDRESS_ERROR, address_error_trap_handler);
|
|
#endif
|
|
#ifdef CONFIG_CPU_SH2A
|
|
set_exception_table_vec(TRAP_DIVZERO_ERROR, do_divide_error);
|
|
set_exception_table_vec(TRAP_DIVOVF_ERROR, do_divide_error);
|
|
#ifdef CONFIG_SH_FPU
|
|
set_exception_table_vec(TRAP_FPU_ERROR, fpu_error_trap_handler);
|
|
#endif
|
|
#endif
|
|
|
|
#ifdef TRAP_UBC
|
|
set_exception_table_vec(TRAP_UBC, breakpoint_trap_handler);
|
|
#endif
|
|
}
|
|
|
|
void show_stack(struct task_struct *tsk, unsigned long *sp)
|
|
{
|
|
unsigned long stack;
|
|
|
|
if (!tsk)
|
|
tsk = current;
|
|
if (tsk == current)
|
|
sp = (unsigned long *)current_stack_pointer;
|
|
else
|
|
sp = (unsigned long *)tsk->thread.sp;
|
|
|
|
stack = (unsigned long)sp;
|
|
dump_mem("Stack: ", stack, THREAD_SIZE +
|
|
(unsigned long)task_stack_page(tsk));
|
|
show_trace(tsk, sp, NULL);
|
|
}
|
|
|
|
void dump_stack(void)
|
|
{
|
|
show_stack(NULL, NULL);
|
|
}
|
|
EXPORT_SYMBOL(dump_stack);
|