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-rw-r--r--arch/sh/kernel/traps_32.c919
1 files changed, 919 insertions, 0 deletions
diff --git a/arch/sh/kernel/traps_32.c b/arch/sh/kernel/traps_32.c
new file mode 100644
index 000000000000..2e58f7a6b746
--- /dev/null
+++ b/arch/sh/kernel/traps_32.c
@@ -0,0 +1,919 @@
+/*
+ * '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 - 2007 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/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 <asm/system.h>
+#include <asm/uaccess.h>
+
+#ifdef CONFIG_SH_KGDB
+#include <asm/kgdb.h>
+#define CHK_REMOTE_DEBUG(regs) \
+{ \
+ if (kgdb_debug_hook && !user_mode(regs))\
+ (*kgdb_debug_hook)(regs); \
+}
+#else
+#define CHK_REMOTE_DEBUG(regs)
+#endif
+
+#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_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();
+
+ console_verbose();
+ spin_lock_irq(&die_lock);
+ bust_spinlocks(1);
+
+ printk("%s: %04lx [#%d]\n", str, err & 0xffff, ++die_counter);
+
+ CHK_REMOTE_DEBUG(regs);
+ 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));
+
+ bust_spinlocks(0);
+ add_taint(TAINT_DIE);
+ spin_unlock_irq(&die_lock);
+
+ if (kexec_should_crash(current))
+ crash_kexec(regs);
+
+ if (in_interrupt())
+ panic("Fatal exception in interrupt");
+
+ if (panic_on_oops)
+ panic("Fatal exception");
+
+ oops_exit();
+ 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
+ * - return 0 if fixed-up, -EFAULT if non-fatal (to the kernel) fault
+ */
+static int 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 0;
+ }
+ die(str, regs, err);
+ }
+ return -EFAULT;
+}
+
+/*
+ * 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(u16 instruction, struct pt_regs *regs)
+{
+ int ret, index, count;
+ unsigned long *rm, *rn;
+ unsigned char *src, *dst;
+
+ index = (instruction>>8)&15; /* 0x0F00 */
+ rn = &regs->regs[index];
+
+ index = (instruction>>4)&15; /* 0x00F0 */
+ rm = &regs->regs[index];
+
+ count = 1<<(instruction&3);
+
+ ret = -EFAULT;
+ switch (instruction>>12) {
+ case 0: /* mov.[bwl] to/from memory via r0+rn */
+ if (instruction & 8) {
+ /* from memory */
+ src = (unsigned char*) *rm;
+ src += regs->regs[0];
+ dst = (unsigned char*) rn;
+ *(unsigned long*)dst = 0;
+
+#ifdef __LITTLE_ENDIAN__
+ if (copy_from_user(dst, src, count))
+ goto fetch_fault;
+
+ if ((count == 2) && dst[1] & 0x80) {
+ dst[2] = 0xff;
+ dst[3] = 0xff;
+ }
+#else
+ dst += 4-count;
+
+ if (__copy_user(dst, src, count))
+ goto fetch_fault;
+
+ if ((count == 2) && dst[2] & 0x80) {
+ dst[0] = 0xff;
+ dst[1] = 0xff;
+ }
+#endif
+ } else {
+ /* to memory */
+ src = (unsigned char*) rm;
+#if !defined(__LITTLE_ENDIAN__)
+ src += 4-count;
+#endif
+ dst = (unsigned char*) *rn;
+ dst += regs->regs[0];
+
+ if (copy_to_user(dst, src, count))
+ goto fetch_fault;
+ }
+ ret = 0;
+ break;
+
+ case 1: /* mov.l Rm,@(disp,Rn) */
+ src = (unsigned char*) rm;
+ dst = (unsigned char*) *rn;
+ dst += (instruction&0x000F)<<2;
+
+ if (copy_to_user(dst,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;
+ dst = (unsigned char*) *rn;
+#if !defined(__LITTLE_ENDIAN__)
+ src += 4-count;
+#endif
+ if (copy_to_user(dst, src, count))
+ goto fetch_fault;
+ ret = 0;
+ break;
+
+ case 5: /* mov.l @(disp,Rm),Rn */
+ src = (unsigned char*) *rm;
+ src += (instruction&0x000F)<<2;
+ dst = (unsigned char*) rn;
+ *(unsigned long*)dst = 0;
+
+ if (copy_from_user(dst,src,4))
+ goto fetch_fault;
+ ret = 0;
+ break;
+
+ case 6: /* mov.[bwl] from memory, possibly with post-increment */
+ src = (unsigned char*) *rm;
+ if (instruction & 4)
+ *rm += count;
+ dst = (unsigned char*) rn;
+ *(unsigned long*)dst = 0;
+
+#ifdef __LITTLE_ENDIAN__
+ if (copy_from_user(dst, src, count))
+ goto fetch_fault;
+
+ if ((count == 2) && dst[1] & 0x80) {
+ dst[2] = 0xff;
+ dst[3] = 0xff;
+ }
+#else
+ dst += 4-count;
+
+ if (copy_from_user(dst, src, count))
+ goto fetch_fault;
+
+ if ((count == 2) && dst[2] & 0x80) {
+ dst[0] = 0xff;
+ dst[1] = 0xff;
+ }
+#endif
+ ret = 0;
+ break;
+
+ case 8:
+ switch ((instruction&0xFF00)>>8) {
+ case 0x81: /* mov.w R0,@(disp,Rn) */
+ src = (unsigned char*) &regs->regs[0];
+#if !defined(__LITTLE_ENDIAN__)
+ src += 2;
+#endif
+ dst = (unsigned char*) *rm; /* called Rn in the spec */
+ dst += (instruction&0x000F)<<1;
+
+ if (copy_to_user(dst, src, 2))
+ goto fetch_fault;
+ ret = 0;
+ break;
+
+ case 0x85: /* mov.w @(disp,Rm),R0 */
+ src = (unsigned char*) *rm;
+ src += (instruction&0x000F)<<1;
+ dst = (unsigned char*) &regs->regs[0];
+ *(unsigned long*)dst = 0;
+
+#if !defined(__LITTLE_ENDIAN__)
+ dst += 2;
+#endif
+
+ if (copy_from_user(dst, src, 2))
+ goto fetch_fault;
+
+#ifdef __LITTLE_ENDIAN__
+ if (dst[1] & 0x80) {
+ dst[2] = 0xff;
+ dst[3] = 0xff;
+ }
+#else
+ if (dst[2] & 0x80) {
+ dst[0] = 0xff;
+ dst[1] = 0xff;
+ }
+#endif
+ ret = 0;
+ break;
+ }
+ break;
+ }
+ return ret;
+
+ fetch_fault:
+ /* Argh. Address not only misaligned but also non-existent.
+ * Raise an EFAULT and see if it's trapped
+ */
+ return die_if_no_fixup("Fault in unaligned fixup", regs, 0);
+}
+
+/*
+ * emulate the instruction in the delay slot
+ * - fetches the instruction from PC+2
+ */
+static inline int handle_unaligned_delayslot(struct pt_regs *regs)
+{
+ u16 instruction;
+
+ if (copy_from_user(&instruction, (u16 *)(regs->pc+2), 2)) {
+ /* 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);
+}
+
+/*
+ * 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)
+
+/*
+ * XXX: SH-2A needs this too, but it needs an overhaul thanks to mixed 32-bit
+ * opcodes..
+ */
+#ifndef CONFIG_CPU_SH2A
+static int handle_unaligned_notify_count = 10;
+
+static int handle_unaligned_access(u16 instruction, struct pt_regs *regs)
+{
+ u_int rm;
+ int ret, index;
+
+ index = (instruction>>8)&15; /* 0x0F00 */
+ rm = regs->regs[index];
+
+ /* shout about the first ten userspace fixups */
+ if (user_mode(regs) && handle_unaligned_notify_count>0) {
+ handle_unaligned_notify_count--;
+
+ printk(KERN_NOTICE "Fixing up unaligned userspace access "
+ "in \"%s\" pid=%d pc=0x%p ins=0x%04hx\n",
+ current->comm, task_pid_nr(current),
+ (u16 *)regs->pc, instruction);
+ }
+
+ ret = -EFAULT;
+ switch (instruction&0xF000) {
+ case 0x0000:
+ if (instruction==0x000B) {
+ /* rts */
+ ret = handle_unaligned_delayslot(regs);
+ if (ret==0)
+ regs->pc = regs->pr;
+ }
+ else if ((instruction&0x00FF)==0x0023) {
+ /* braf @Rm */
+ ret = handle_unaligned_delayslot(regs);
+ if (ret==0)
+ regs->pc += rm + 4;
+ }
+ else if ((instruction&0x00FF)==0x0003) {
+ /* bsrf @Rm */
+ ret = handle_unaligned_delayslot(regs);
+ 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_unaligned_delayslot(regs);
+ if (ret==0)
+ regs->pc = rm;
+ }
+ else if ((instruction&0x00FF)==0x000B) {
+ /* jsr @Rm */
+ ret = handle_unaligned_delayslot(regs);
+ 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*/
+ break;
+ case 0x0F00: /* bf/s lab */
+ ret = handle_unaligned_delayslot(regs);
+ 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 */
+ break;
+ case 0x0D00: /* bt/s lab */
+ ret = handle_unaligned_delayslot(regs);
+ 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 0xA000: /* bra label */
+ ret = handle_unaligned_delayslot(regs);
+ if (ret==0)
+ regs->pc += SH_PC_12BIT_OFFSET(instruction);
+ break;
+
+ case 0xB000: /* bsr label */
+ ret = handle_unaligned_delayslot(regs);
+ if (ret==0) {
+ regs->pr = regs->pc + 4;
+ regs->pc += SH_PC_12BIT_OFFSET(instruction);
+ }
+ break;
+ }
+ return ret;
+
+ /* handle non-delay-slot instruction */
+ simple:
+ ret = handle_unaligned_ins(instruction,regs);
+ if (ret==0)
+ regs->pc += instruction_size(instruction);
+ return ret;
+}
+#endif /* CONFIG_CPU_SH2A */
+
+#ifdef CONFIG_CPU_HAS_SR_RB
+#define lookup_exception_vector(x) \
+ __asm__ __volatile__ ("stc r2_bank, %0\n\t" : "=r" ((x)))
+#else
+#define lookup_exception_vector(x) \
+ __asm__ __volatile__ ("mov r4, %0\n\t" : "=r" ((x)))
+#endif
+
+/*
+ * 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;
+#ifndef CONFIG_CPU_SH2A
+ u16 instruction;
+ int tmp;
+#endif
+
+ /* Intentional ifdef */
+#ifdef CONFIG_CPU_HAS_SR_RB
+ lookup_exception_vector(error_code);
+#endif
+
+ oldfs = get_fs();
+
+ if (user_mode(regs)) {
+ int si_code = BUS_ADRERR;
+
+ local_irq_enable();
+
+ /* bad PC is not something we can fix */
+ if (regs->pc & 1) {
+ si_code = BUS_ADRALN;
+ goto uspace_segv;
+ }
+
+#ifndef CONFIG_CPU_SH2A
+ set_fs(USER_DS);
+ if (copy_from_user(&instruction, (u16 *)(regs->pc), 2)) {
+ /* Argh. Fault on the instruction itself.
+ This should never happen non-SMP
+ */
+ set_fs(oldfs);
+ goto uspace_segv;
+ }
+
+ tmp = handle_unaligned_access(instruction, regs);
+ set_fs(oldfs);
+
+ if (tmp==0)
+ return; /* sorted */
+#endif
+
+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 {
+ if (regs->pc & 1)
+ die("unaligned program counter", regs, error_code);
+
+#ifndef CONFIG_CPU_SH2A
+ set_fs(KERNEL_DS);
+ if (copy_from_user(&instruction, (u16 *)(regs->pc), 2)) {
+ /* Argh. Fault on the instruction itself.
+ This should never happen non-SMP
+ */
+ set_fs(oldfs);
+ die("insn faulting in do_address_error", regs, 0);
+ }
+
+ handle_unaligned_access(instruction, regs);
+ set_fs(oldfs);
+#else
+ printk(KERN_NOTICE "Killing process \"%s\" due to unaligned "
+ "access\n", current->comm);
+
+ force_sig(SIGSEGV, current);
+#endif
+ }
+}
+
+#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;
+ return;
+ }
+#endif
+
+ lookup_exception_vector(error_code);
+
+ local_irq_enable();
+ CHK_REMOTE_DEBUG(regs);
+ 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 & 0xfd00) == 0x8d00) {
+ regs->pc += SH_PC_8BIT_OFFSET(inst);
+ return 0;
+ }
+
+ if ((inst & 0xe000) == 0xa000) {
+ regs->pc += SH_PC_12BIT_OFFSET(inst);
+ return 0;
+ }
+
+ if ((inst & 0xf0df) == 0x0003) {
+ regs->pc += regs->regs[(inst & 0x0f00) >> 8] + 4;
+ return 0;
+ }
+
+ if ((inst & 0xf0df) == 0x400b) {
+ regs->pc = regs->regs[(inst & 0x0f00) >> 8];
+ return 0;
+ }
+
+ if ((inst & 0xffff) == 0x000b) {
+ 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 error_code;
+ struct task_struct *tsk = current;
+#ifdef CONFIG_SH_FPU_EMU
+ unsigned short inst = 0;
+
+ 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
+
+ lookup_exception_vector(error_code);
+
+ local_irq_enable();
+ CHK_REMOTE_DEBUG(regs);
+ force_sig(SIGILL, tsk);
+ die_if_no_fixup("illegal slot instruction", regs, error_code);
+}
+
+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;
+
+ lookup_exception_vector(ex);
+ die_if_kernel("exception", regs, ex);
+}
+
+#if defined(CONFIG_SH_STANDARD_BIOS)
+void *gdb_vbr_vector;
+
+static inline void __init gdb_vbr_init(void)
+{
+ register unsigned long vbr;
+
+ /*
+ * Read the old value of the VBR register to initialise
+ * the vector through which debug and BIOS traps are
+ * delegated by the Linux trap handler.
+ */
+ asm volatile("stc vbr, %0" : "=r" (vbr));
+
+ gdb_vbr_vector = (void *)(vbr + 0x100);
+ printk("Setting GDB trap vector to 0x%08lx\n",
+ (unsigned long)gdb_vbr_vector);
+}
+#endif
+
+void __cpuinit per_cpu_trap_init(void)
+{
+ extern void *vbr_base;
+
+#ifdef CONFIG_SH_STANDARD_BIOS
+ if (raw_smp_processor_id() == 0)
+ gdb_vbr_init();
+#endif
+
+ /* 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");
+}
+
+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)
+#ifdef CONFIG_CPU_SUBTYPE_SHX3
+ set_exception_table_evt(0xd80, fpu_state_restore_trap_handler);
+ set_exception_table_evt(0xda0, fpu_state_restore_trap_handler);
+#else
+ set_exception_table_evt(0x800, fpu_state_restore_trap_handler);
+ set_exception_table_evt(0x820, fpu_state_restore_trap_handler);
+#endif
+#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);
+#endif
+
+ /* Setup VBR for boot cpu */
+ per_cpu_trap_init();
+}
+
+void show_trace(struct task_struct *tsk, unsigned long *sp,
+ struct pt_regs *regs)
+{
+ unsigned long addr;
+
+ if (regs && user_mode(regs))
+ return;
+
+ printk("\nCall trace: ");
+#ifdef CONFIG_KALLSYMS
+ printk("\n");
+#endif
+
+ while (!kstack_end(sp)) {
+ addr = *sp++;
+ if (kernel_text_address(addr))
+ print_ip_sym(addr);
+ }
+
+ printk("\n");
+
+ if (!tsk)
+ tsk = current;
+
+ debug_show_held_locks(tsk);
+}
+
+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);
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-18 23:01:30 +0100