| /* |
| * '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/kallsyms.h> |
| #include <linux/io.h> |
| #include <linux/bug.h> |
| #include <linux/debug_locks.h> |
| #include <linux/kdebug.h> |
| #include <linux/limits.h> |
| #include <linux/sysfs.h> |
| #include <linux/uaccess.h> |
| #include <linux/perf_event.h> |
| #include <linux/sched/task_stack.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 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; |
| 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); |
| |
| force_sig_fault(SIGBUS, si_code, (void __user *)address, 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) |
| { |
| int code; |
| |
| switch (r4) { |
| case TRAP_DIVZERO_ERROR: |
| code = FPE_INTDIV; |
| break; |
| case TRAP_DIVOVF_ERROR: |
| code = FPE_INTOVF; |
| break; |
| default: |
| /* Let gcc know unhandled cases don't make it past here */ |
| return; |
| } |
| force_sig_fault(SIGFPE, code, NULL, current); |
| } |
| #endif |
| |
| asmlinkage void do_reserved_inst(void) |
| { |
| struct pt_regs *regs = current_pt_regs(); |
| 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(void) |
| { |
| struct pt_regs *regs = current_pt_regs(); |
| 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(void) |
| { |
| long ex; |
| |
| ex = lookup_exception_vector(); |
| die_if_kernel("exception", current_pt_regs(), ex); |
| } |
| |
| void 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 |
| } |