linux/arch/mn10300/mm/misalignment.c
David Howells b308bf3be1 MN10300: Extract the displacement from an insn correctly in misalignment fixup
Extract the displacement from an MN10300 instruction correctly in the
misalignment fixup handler.

The code should extract the displacement in LSB order, not MSB order.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2008-11-12 10:41:17 -08:00

865 lines
26 KiB
C

/* MN10300 Misalignment fixup handler
*
* Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
* Written by David Howells (dhowells@redhat.com)
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public Licence
* as published by the Free Software Foundation; either version
* 2 of the Licence, or (at your option) any later version.
*/
#include <linux/module.h>
#include <linux/sched.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/ptrace.h>
#include <linux/timer.h>
#include <linux/mm.h>
#include <linux/smp.h>
#include <linux/smp_lock.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/spinlock.h>
#include <linux/interrupt.h>
#include <linux/pci.h>
#include <asm/processor.h>
#include <asm/system.h>
#include <asm/uaccess.h>
#include <asm/io.h>
#include <asm/atomic.h>
#include <asm/smp.h>
#include <asm/pgalloc.h>
#include <asm/cpu-regs.h>
#include <asm/busctl-regs.h>
#include <asm/fpu.h>
#include <asm/gdb-stub.h>
#include <asm/asm-offsets.h>
#if 0
#define kdebug(FMT, ...) printk(KERN_DEBUG "MISALIGN: "FMT"\n", ##__VA_ARGS__)
#else
#define kdebug(FMT, ...) do {} while (0)
#endif
static int misalignment_addr(unsigned long *registers, unsigned params,
unsigned opcode, unsigned long disp,
void **_address, unsigned long **_postinc);
static int misalignment_reg(unsigned long *registers, unsigned params,
unsigned opcode, unsigned long disp,
unsigned long **_register);
static const unsigned Dreg_index[] = {
REG_D0 >> 2, REG_D1 >> 2, REG_D2 >> 2, REG_D3 >> 2
};
static const unsigned Areg_index[] = {
REG_A0 >> 2, REG_A1 >> 2, REG_A2 >> 2, REG_A3 >> 2
};
static const unsigned Rreg_index[] = {
REG_E0 >> 2, REG_E1 >> 2, REG_E2 >> 2, REG_E3 >> 2,
REG_E4 >> 2, REG_E5 >> 2, REG_E6 >> 2, REG_E7 >> 2,
REG_A0 >> 2, REG_A1 >> 2, REG_A2 >> 2, REG_A3 >> 2,
REG_D0 >> 2, REG_D1 >> 2, REG_D2 >> 2, REG_D3 >> 2
};
enum format_id {
FMT_S0,
FMT_S1,
FMT_S2,
FMT_S4,
FMT_D0,
FMT_D1,
FMT_D2,
FMT_D4,
FMT_D6,
FMT_D7,
FMT_D8,
FMT_D9,
};
static const struct {
u_int8_t opsz, dispsz;
} format_tbl[16] = {
[FMT_S0] = { 8, 0 },
[FMT_S1] = { 8, 8 },
[FMT_S2] = { 8, 16 },
[FMT_S4] = { 8, 32 },
[FMT_D0] = { 16, 0 },
[FMT_D1] = { 16, 8 },
[FMT_D2] = { 16, 16 },
[FMT_D4] = { 16, 32 },
[FMT_D6] = { 24, 0 },
[FMT_D7] = { 24, 8 },
[FMT_D8] = { 24, 24 },
[FMT_D9] = { 24, 32 },
};
enum value_id {
DM0, /* data reg in opcode in bits 0-1 */
DM1, /* data reg in opcode in bits 2-3 */
DM2, /* data reg in opcode in bits 4-5 */
AM0, /* addr reg in opcode in bits 0-1 */
AM1, /* addr reg in opcode in bits 2-3 */
AM2, /* addr reg in opcode in bits 4-5 */
RM0, /* reg in opcode in bits 0-3 */
RM1, /* reg in opcode in bits 2-5 */
RM2, /* reg in opcode in bits 4-7 */
RM4, /* reg in opcode in bits 8-11 */
RM6, /* reg in opcode in bits 12-15 */
RD0, /* reg in displacement in bits 0-3 */
RD2, /* reg in displacement in bits 4-7 */
SP, /* stack pointer */
SD8, /* 8-bit signed displacement */
SD16, /* 16-bit signed displacement */
SD24, /* 24-bit signed displacement */
SIMM4_2, /* 4-bit signed displacement in opcode bits 4-7 */
SIMM8, /* 8-bit signed immediate */
IMM8, /* 8-bit unsigned immediate */
IMM16, /* 16-bit unsigned immediate */
IMM24, /* 24-bit unsigned immediate */
IMM32, /* 32-bit unsigned immediate */
IMM32_HIGH8, /* 32-bit unsigned immediate, LSB in opcode */
IMM32_MEM, /* 32-bit unsigned displacement */
IMM32_HIGH8_MEM, /* 32-bit unsigned displacement, LSB in opcode */
DN0 = DM0,
DN1 = DM1,
DN2 = DM2,
AN0 = AM0,
AN1 = AM1,
AN2 = AM2,
RN0 = RM0,
RN1 = RM1,
RN2 = RM2,
RN4 = RM4,
RN6 = RM6,
DI = DM1,
RI = RM2,
};
struct mn10300_opcode {
const char *name;
u_int32_t opcode;
u_int32_t opmask;
unsigned exclusion;
enum format_id format;
unsigned cpu_mask;
#define AM33 330
unsigned params[2];
#define MEM(ADDR) (0x80000000 | (ADDR))
#define MEM2(ADDR1, ADDR2) (0x80000000 | (ADDR1) << 8 | (ADDR2))
#define MEMINC(ADDR) (0x81000000 | (ADDR))
#define MEMINC2(ADDR, INC) (0x81000000 | (ADDR) << 8 | (INC))
};
/* LIBOPCODES EXCERPT
Assemble Matsushita MN10300 instructions.
Copyright 1996, 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public Licence as published by
the Free Software Foundation; either version 2 of the Licence, 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 Licence for more details.
You should have received a copy of the GNU General Public Licence
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
static const struct mn10300_opcode mn10300_opcodes[] = {
{ "mov", 0x4200, 0xf300, 0, FMT_S1, 0, {DM1, MEM2(IMM8, SP)}},
{ "mov", 0x4300, 0xf300, 0, FMT_S1, 0, {AM1, MEM2(IMM8, SP)}},
{ "mov", 0x5800, 0xfc00, 0, FMT_S1, 0, {MEM2(IMM8, SP), DN0}},
{ "mov", 0x5c00, 0xfc00, 0, FMT_S1, 0, {MEM2(IMM8, SP), AN0}},
{ "mov", 0x60, 0xf0, 0, FMT_S0, 0, {DM1, MEM(AN0)}},
{ "mov", 0x70, 0xf0, 0, FMT_S0, 0, {MEM(AM0), DN1}},
{ "mov", 0xf000, 0xfff0, 0, FMT_D0, 0, {MEM(AM0), AN1}},
{ "mov", 0xf010, 0xfff0, 0, FMT_D0, 0, {AM1, MEM(AN0)}},
{ "mov", 0xf300, 0xffc0, 0, FMT_D0, 0, {MEM2(DI, AM0), DN2}},
{ "mov", 0xf340, 0xffc0, 0, FMT_D0, 0, {DM2, MEM2(DI, AN0)}},
{ "mov", 0xf380, 0xffc0, 0, FMT_D0, 0, {MEM2(DI, AM0), AN2}},
{ "mov", 0xf3c0, 0xffc0, 0, FMT_D0, 0, {AM2, MEM2(DI, AN0)}},
{ "mov", 0xf80000, 0xfff000, 0, FMT_D1, 0, {MEM2(SD8, AM0), DN1}},
{ "mov", 0xf81000, 0xfff000, 0, FMT_D1, 0, {DM1, MEM2(SD8, AN0)}},
{ "mov", 0xf82000, 0xfff000, 0, FMT_D1, 0, {MEM2(SD8,AM0), AN1}},
{ "mov", 0xf83000, 0xfff000, 0, FMT_D1, 0, {AM1, MEM2(SD8, AN0)}},
{ "mov", 0xf8f000, 0xfffc00, 0, FMT_D1, AM33, {MEM2(SD8, AM0), SP}},
{ "mov", 0xf8f400, 0xfffc00, 0, FMT_D1, AM33, {SP, MEM2(SD8, AN0)}},
{ "mov", 0xf90a00, 0xffff00, 0, FMT_D6, AM33, {MEM(RM0), RN2}},
{ "mov", 0xf91a00, 0xffff00, 0, FMT_D6, AM33, {RM2, MEM(RN0)}},
{ "mov", 0xf96a00, 0xffff00, 0x12, FMT_D6, AM33, {MEMINC(RM0), RN2}},
{ "mov", 0xf97a00, 0xffff00, 0, FMT_D6, AM33, {RM2, MEMINC(RN0)}},
{ "mov", 0xfa000000, 0xfff00000, 0, FMT_D2, 0, {MEM2(SD16, AM0), DN1}},
{ "mov", 0xfa100000, 0xfff00000, 0, FMT_D2, 0, {DM1, MEM2(SD16, AN0)}},
{ "mov", 0xfa200000, 0xfff00000, 0, FMT_D2, 0, {MEM2(SD16, AM0), AN1}},
{ "mov", 0xfa300000, 0xfff00000, 0, FMT_D2, 0, {AM1, MEM2(SD16, AN0)}},
{ "mov", 0xfa900000, 0xfff30000, 0, FMT_D2, 0, {AM1, MEM2(IMM16, SP)}},
{ "mov", 0xfa910000, 0xfff30000, 0, FMT_D2, 0, {DM1, MEM2(IMM16, SP)}},
{ "mov", 0xfab00000, 0xfffc0000, 0, FMT_D2, 0, {MEM2(IMM16, SP), AN0}},
{ "mov", 0xfab40000, 0xfffc0000, 0, FMT_D2, 0, {MEM2(IMM16, SP), DN0}},
{ "mov", 0xfb0a0000, 0xffff0000, 0, FMT_D7, AM33, {MEM2(SD8, RM0), RN2}},
{ "mov", 0xfb1a0000, 0xffff0000, 0, FMT_D7, AM33, {RM2, MEM2(SD8, RN0)}},
{ "mov", 0xfb6a0000, 0xffff0000, 0x22, FMT_D7, AM33, {MEMINC2 (RM0, SIMM8), RN2}},
{ "mov", 0xfb7a0000, 0xffff0000, 0, FMT_D7, AM33, {RM2, MEMINC2 (RN0, SIMM8)}},
{ "mov", 0xfb8a0000, 0xffff0f00, 0, FMT_D7, AM33, {MEM2(IMM8, SP), RN2}},
{ "mov", 0xfb8e0000, 0xffff000f, 0, FMT_D7, AM33, {MEM2(RI, RM0), RD2}},
{ "mov", 0xfb9a0000, 0xffff0f00, 0, FMT_D7, AM33, {RM2, MEM2(IMM8, SP)}},
{ "mov", 0xfb9e0000, 0xffff000f, 0, FMT_D7, AM33, {RD2, MEM2(RI, RN0)}},
{ "mov", 0xfc000000, 0xfff00000, 0, FMT_D4, 0, {MEM2(IMM32,AM0), DN1}},
{ "mov", 0xfc100000, 0xfff00000, 0, FMT_D4, 0, {DM1, MEM2(IMM32,AN0)}},
{ "mov", 0xfc200000, 0xfff00000, 0, FMT_D4, 0, {MEM2(IMM32,AM0), AN1}},
{ "mov", 0xfc300000, 0xfff00000, 0, FMT_D4, 0, {AM1, MEM2(IMM32,AN0)}},
{ "mov", 0xfc800000, 0xfff30000, 0, FMT_D4, 0, {AM1, MEM(IMM32_MEM)}},
{ "mov", 0xfc810000, 0xfff30000, 0, FMT_D4, 0, {DM1, MEM(IMM32_MEM)}},
{ "mov", 0xfc900000, 0xfff30000, 0, FMT_D4, 0, {AM1, MEM2(IMM32, SP)}},
{ "mov", 0xfc910000, 0xfff30000, 0, FMT_D4, 0, {DM1, MEM2(IMM32, SP)}},
{ "mov", 0xfca00000, 0xfffc0000, 0, FMT_D4, 0, {MEM(IMM32_MEM), AN0}},
{ "mov", 0xfca40000, 0xfffc0000, 0, FMT_D4, 0, {MEM(IMM32_MEM), DN0}},
{ "mov", 0xfcb00000, 0xfffc0000, 0, FMT_D4, 0, {MEM2(IMM32, SP), AN0}},
{ "mov", 0xfcb40000, 0xfffc0000, 0, FMT_D4, 0, {MEM2(IMM32, SP), DN0}},
{ "mov", 0xfd0a0000, 0xffff0000, 0, FMT_D8, AM33, {MEM2(SD24, RM0), RN2}},
{ "mov", 0xfd1a0000, 0xffff0000, 0, FMT_D8, AM33, {RM2, MEM2(SD24, RN0)}},
{ "mov", 0xfd6a0000, 0xffff0000, 0x22, FMT_D8, AM33, {MEMINC2 (RM0, IMM24), RN2}},
{ "mov", 0xfd7a0000, 0xffff0000, 0, FMT_D8, AM33, {RM2, MEMINC2 (RN0, IMM24)}},
{ "mov", 0xfd8a0000, 0xffff0f00, 0, FMT_D8, AM33, {MEM2(IMM24, SP), RN2}},
{ "mov", 0xfd9a0000, 0xffff0f00, 0, FMT_D8, AM33, {RM2, MEM2(IMM24, SP)}},
{ "mov", 0xfe0a0000, 0xffff0000, 0, FMT_D9, AM33, {MEM2(IMM32_HIGH8,RM0), RN2}},
{ "mov", 0xfe0a0000, 0xffff0000, 0, FMT_D9, AM33, {MEM2(IMM32_HIGH8,RM0), RN2}},
{ "mov", 0xfe0e0000, 0xffff0f00, 0, FMT_D9, AM33, {MEM(IMM32_HIGH8_MEM), RN2}},
{ "mov", 0xfe1a0000, 0xffff0000, 0, FMT_D9, AM33, {RM2, MEM2(IMM32_HIGH8, RN0)}},
{ "mov", 0xfe1a0000, 0xffff0000, 0, FMT_D9, AM33, {RM2, MEM2(IMM32_HIGH8, RN0)}},
{ "mov", 0xfe1e0000, 0xffff0f00, 0, FMT_D9, AM33, {RM2, MEM(IMM32_HIGH8_MEM)}},
{ "mov", 0xfe6a0000, 0xffff0000, 0x22, FMT_D9, AM33, {MEMINC2 (RM0, IMM32_HIGH8), RN2}},
{ "mov", 0xfe7a0000, 0xffff0000, 0, FMT_D9, AM33, {RN2, MEMINC2 (RM0, IMM32_HIGH8)}},
{ "mov", 0xfe8a0000, 0xffff0f00, 0, FMT_D9, AM33, {MEM2(IMM32_HIGH8, SP), RN2}},
{ "mov", 0xfe9a0000, 0xffff0f00, 0, FMT_D9, AM33, {RM2, MEM2(IMM32_HIGH8, SP)}},
{ "movhu", 0xf060, 0xfff0, 0, FMT_D0, 0, {MEM(AM0), DN1}},
{ "movhu", 0xf070, 0xfff0, 0, FMT_D0, 0, {DM1, MEM(AN0)}},
{ "movhu", 0xf480, 0xffc0, 0, FMT_D0, 0, {MEM2(DI, AM0), DN2}},
{ "movhu", 0xf4c0, 0xffc0, 0, FMT_D0, 0, {DM2, MEM2(DI, AN0)}},
{ "movhu", 0xf86000, 0xfff000, 0, FMT_D1, 0, {MEM2(SD8, AM0), DN1}},
{ "movhu", 0xf87000, 0xfff000, 0, FMT_D1, 0, {DM1, MEM2(SD8, AN0)}},
{ "movhu", 0xf89300, 0xfff300, 0, FMT_D1, 0, {DM1, MEM2(IMM8, SP)}},
{ "movhu", 0xf8bc00, 0xfffc00, 0, FMT_D1, 0, {MEM2(IMM8, SP), DN0}},
{ "movhu", 0xf94a00, 0xffff00, 0, FMT_D6, AM33, {MEM(RM0), RN2}},
{ "movhu", 0xf95a00, 0xffff00, 0, FMT_D6, AM33, {RM2, MEM(RN0)}},
{ "movhu", 0xf9ea00, 0xffff00, 0x12, FMT_D6, AM33, {MEMINC(RM0), RN2}},
{ "movhu", 0xf9fa00, 0xffff00, 0, FMT_D6, AM33, {RM2, MEMINC(RN0)}},
{ "movhu", 0xfa600000, 0xfff00000, 0, FMT_D2, 0, {MEM2(SD16, AM0), DN1}},
{ "movhu", 0xfa700000, 0xfff00000, 0, FMT_D2, 0, {DM1, MEM2(SD16, AN0)}},
{ "movhu", 0xfa930000, 0xfff30000, 0, FMT_D2, 0, {DM1, MEM2(IMM16, SP)}},
{ "movhu", 0xfabc0000, 0xfffc0000, 0, FMT_D2, 0, {MEM2(IMM16, SP), DN0}},
{ "movhu", 0xfb4a0000, 0xffff0000, 0, FMT_D7, AM33, {MEM2(SD8, RM0), RN2}},
{ "movhu", 0xfb5a0000, 0xffff0000, 0, FMT_D7, AM33, {RM2, MEM2(SD8, RN0)}},
{ "movhu", 0xfbca0000, 0xffff0f00, 0, FMT_D7, AM33, {MEM2(IMM8, SP), RN2}},
{ "movhu", 0xfbce0000, 0xffff000f, 0, FMT_D7, AM33, {MEM2(RI, RM0), RD2}},
{ "movhu", 0xfbda0000, 0xffff0f00, 0, FMT_D7, AM33, {RM2, MEM2(IMM8, SP)}},
{ "movhu", 0xfbde0000, 0xffff000f, 0, FMT_D7, AM33, {RD2, MEM2(RI, RN0)}},
{ "movhu", 0xfbea0000, 0xffff0000, 0x22, FMT_D7, AM33, {MEMINC2 (RM0, SIMM8), RN2}},
{ "movhu", 0xfbfa0000, 0xffff0000, 0, FMT_D7, AM33, {RM2, MEMINC2 (RN0, SIMM8)}},
{ "movhu", 0xfc600000, 0xfff00000, 0, FMT_D4, 0, {MEM2(IMM32,AM0), DN1}},
{ "movhu", 0xfc700000, 0xfff00000, 0, FMT_D4, 0, {DM1, MEM2(IMM32,AN0)}},
{ "movhu", 0xfc830000, 0xfff30000, 0, FMT_D4, 0, {DM1, MEM(IMM32_MEM)}},
{ "movhu", 0xfc930000, 0xfff30000, 0, FMT_D4, 0, {DM1, MEM2(IMM32, SP)}},
{ "movhu", 0xfcac0000, 0xfffc0000, 0, FMT_D4, 0, {MEM(IMM32_MEM), DN0}},
{ "movhu", 0xfcbc0000, 0xfffc0000, 0, FMT_D4, 0, {MEM2(IMM32, SP), DN0}},
{ "movhu", 0xfd4a0000, 0xffff0000, 0, FMT_D8, AM33, {MEM2(SD24, RM0), RN2}},
{ "movhu", 0xfd5a0000, 0xffff0000, 0, FMT_D8, AM33, {RM2, MEM2(SD24, RN0)}},
{ "movhu", 0xfdca0000, 0xffff0f00, 0, FMT_D8, AM33, {MEM2(IMM24, SP), RN2}},
{ "movhu", 0xfdda0000, 0xffff0f00, 0, FMT_D8, AM33, {RM2, MEM2(IMM24, SP)}},
{ "movhu", 0xfdea0000, 0xffff0000, 0x22, FMT_D8, AM33, {MEMINC2 (RM0, IMM24), RN2}},
{ "movhu", 0xfdfa0000, 0xffff0000, 0, FMT_D8, AM33, {RM2, MEMINC2 (RN0, IMM24)}},
{ "movhu", 0xfe4a0000, 0xffff0000, 0, FMT_D9, AM33, {MEM2(IMM32_HIGH8,RM0), RN2}},
{ "movhu", 0xfe4e0000, 0xffff0f00, 0, FMT_D9, AM33, {MEM(IMM32_HIGH8_MEM), RN2}},
{ "movhu", 0xfe5a0000, 0xffff0000, 0, FMT_D9, AM33, {RM2, MEM2(IMM32_HIGH8, RN0)}},
{ "movhu", 0xfe5e0000, 0xffff0f00, 0, FMT_D9, AM33, {RM2, MEM(IMM32_HIGH8_MEM)}},
{ "movhu", 0xfeca0000, 0xffff0f00, 0, FMT_D9, AM33, {MEM2(IMM32_HIGH8, SP), RN2}},
{ "movhu", 0xfeda0000, 0xffff0f00, 0, FMT_D9, AM33, {RM2, MEM2(IMM32_HIGH8, SP)}},
{ "movhu", 0xfeea0000, 0xffff0000, 0x22, FMT_D9, AM33, {MEMINC2 (RM0, IMM32_HIGH8), RN2}},
{ "movhu", 0xfefa0000, 0xffff0000, 0, FMT_D9, AM33, {RN2, MEMINC2 (RM0, IMM32_HIGH8)}},
{ 0, 0, 0, 0, 0, 0, {0}},
};
/*
* fix up misalignment problems where possible
*/
asmlinkage void misalignment(struct pt_regs *regs, enum exception_code code)
{
const struct exception_table_entry *fixup;
const struct mn10300_opcode *pop;
unsigned long *registers = (unsigned long *) regs;
unsigned long data, *store, *postinc, disp;
mm_segment_t seg;
siginfo_t info;
uint32_t opcode, noc, xo, xm;
uint8_t *pc, byte;
void *address;
unsigned tmp, npop, dispsz, loop;
kdebug("==>misalignment({pc=%lx})", regs->pc);
if (in_interrupt())
die("Misalignment trap in interrupt context", regs, code);
if (regs->epsw & EPSW_IE)
asm volatile("or %0,epsw" : : "i"(EPSW_IE));
seg = get_fs();
set_fs(KERNEL_DS);
fixup = search_exception_tables(regs->pc);
/* first thing to do is to match the opcode */
pc = (u_int8_t *) regs->pc;
if (__get_user(byte, pc) != 0)
goto fetch_error;
opcode = byte;
noc = 8;
for (pop = mn10300_opcodes; pop->name; pop++) {
npop = ilog2(pop->opcode | pop->opmask);
if (npop <= 0 || npop > 31)
continue;
npop = (npop + 8) & ~7;
got_more_bits:
if (npop == noc) {
if ((opcode & pop->opmask) == pop->opcode)
goto found_opcode;
} else if (npop > noc) {
xo = pop->opcode >> (npop - noc);
xm = pop->opmask >> (npop - noc);
if ((opcode & xm) != xo)
continue;
/* we've got a partial match (an exact match on the
* first N bytes), so we need to get some more data */
pc++;
if (__get_user(byte, pc) != 0)
goto fetch_error;
opcode = opcode << 8 | byte;
noc += 8;
goto got_more_bits;
} else {
/* there's already been a partial match as long as the
* complete match we're now considering, so this one
* should't match */
continue;
}
}
/* didn't manage to find a fixup */
if (!user_mode(regs))
printk(KERN_CRIT "MISALIGN: %lx: unsupported instruction %x\n",
regs->pc, opcode);
failed:
set_fs(seg);
if (die_if_no_fixup("misalignment error", regs, code))
return;
info.si_signo = SIGBUS;
info.si_errno = 0;
info.si_code = BUS_ADRALN;
info.si_addr = (void *) regs->pc;
force_sig_info(SIGBUS, &info, current);
return;
/* error reading opcodes */
fetch_error:
if (!user_mode(regs))
printk(KERN_CRIT
"MISALIGN: %p: fault whilst reading instruction data\n",
pc);
goto failed;
bad_addr_mode:
if (!user_mode(regs))
printk(KERN_CRIT
"MISALIGN: %lx: unsupported addressing mode %x\n",
regs->pc, opcode);
goto failed;
bad_reg_mode:
if (!user_mode(regs))
printk(KERN_CRIT
"MISALIGN: %lx: unsupported register mode %x\n",
regs->pc, opcode);
goto failed;
unsupported_instruction:
if (!user_mode(regs))
printk(KERN_CRIT
"MISALIGN: %lx: unsupported instruction %x (%s)\n",
regs->pc, opcode, pop->name);
goto failed;
transfer_failed:
set_fs(seg);
if (fixup) {
regs->pc = fixup->fixup;
return;
}
if (die_if_no_fixup("misalignment fixup", regs, code))
return;
info.si_signo = SIGSEGV;
info.si_errno = 0;
info.si_code = 0;
info.si_addr = (void *) regs->pc;
force_sig_info(SIGSEGV, &info, current);
return;
/* we matched the opcode */
found_opcode:
kdebug("%lx: %x==%x { %x, %x }",
regs->pc, opcode, pop->opcode, pop->params[0], pop->params[1]);
tmp = format_tbl[pop->format].opsz;
if (tmp > noc)
BUG(); /* match was less complete than it ought to have been */
if (tmp < noc) {
tmp = noc - tmp;
opcode >>= tmp;
pc -= tmp >> 3;
}
/* grab the extra displacement (note it's LSB first) */
disp = 0;
dispsz = format_tbl[pop->format].dispsz;
for (loop = 0; loop < dispsz; loop += 8) {
pc++;
if (__get_user(byte, pc) != 0)
goto fetch_error;
disp |= byte << loop;
kdebug("{%p} disp[%02x]=%02x", pc, loop, byte);
}
kdebug("disp=%lx", disp);
set_fs(KERNEL_XDS);
if (fixup || regs->epsw & EPSW_nSL)
set_fs(seg);
tmp = (pop->params[0] ^ pop->params[1]) & 0x80000000;
if (!tmp) {
if (!user_mode(regs))
printk(KERN_CRIT
"MISALIGN: %lx:"
" insn not move to/from memory %x\n",
regs->pc, opcode);
goto failed;
}
if (pop->params[0] & 0x80000000) {
/* move memory to register */
if (!misalignment_addr(registers, pop->params[0], opcode, disp,
&address, &postinc))
goto bad_addr_mode;
if (!misalignment_reg(registers, pop->params[1], opcode, disp,
&store))
goto bad_reg_mode;
if (strcmp(pop->name, "mov") == 0) {
kdebug("mov (%p),DARn", address);
if (copy_from_user(&data, (void *) address, 4) != 0)
goto transfer_failed;
if (pop->params[0] & 0x1000000)
*postinc += 4;
} else if (strcmp(pop->name, "movhu") == 0) {
kdebug("movhu (%p),DARn", address);
data = 0;
if (copy_from_user(&data, (void *) address, 2) != 0)
goto transfer_failed;
if (pop->params[0] & 0x1000000)
*postinc += 2;
} else {
goto unsupported_instruction;
}
*store = data;
} else {
/* move register to memory */
if (!misalignment_reg(registers, pop->params[0], opcode, disp,
&store))
goto bad_reg_mode;
if (!misalignment_addr(registers, pop->params[1], opcode, disp,
&address, &postinc))
goto bad_addr_mode;
data = *store;
if (strcmp(pop->name, "mov") == 0) {
kdebug("mov %lx,(%p)", data, address);
if (copy_to_user((void *) address, &data, 4) != 0)
goto transfer_failed;
if (pop->params[1] & 0x1000000)
*postinc += 4;
} else if (strcmp(pop->name, "movhu") == 0) {
kdebug("movhu %hx,(%p)", (uint16_t) data, address);
if (copy_to_user((void *) address, &data, 2) != 0)
goto transfer_failed;
if (pop->params[1] & 0x1000000)
*postinc += 2;
} else {
goto unsupported_instruction;
}
}
tmp = format_tbl[pop->format].opsz + format_tbl[pop->format].dispsz;
regs->pc += tmp >> 3;
set_fs(seg);
return;
}
/*
* determine the address that was being accessed
*/
static int misalignment_addr(unsigned long *registers, unsigned params,
unsigned opcode, unsigned long disp,
void **_address, unsigned long **_postinc)
{
unsigned long *postinc = NULL, address = 0, tmp;
params &= 0x7fffffff;
do {
switch (params & 0xff) {
case DM0:
postinc = &registers[Dreg_index[opcode & 0x03]];
address += *postinc;
break;
case DM1:
postinc = &registers[Dreg_index[opcode >> 2 & 0x0c]];
address += *postinc;
break;
case DM2:
postinc = &registers[Dreg_index[opcode >> 4 & 0x30]];
address += *postinc;
break;
case AM0:
postinc = &registers[Areg_index[opcode & 0x03]];
address += *postinc;
break;
case AM1:
postinc = &registers[Areg_index[opcode >> 2 & 0x0c]];
address += *postinc;
break;
case AM2:
postinc = &registers[Areg_index[opcode >> 4 & 0x30]];
address += *postinc;
break;
case RM0:
postinc = &registers[Rreg_index[opcode & 0x0f]];
address += *postinc;
break;
case RM1:
postinc = &registers[Rreg_index[opcode >> 2 & 0x0f]];
address += *postinc;
break;
case RM2:
postinc = &registers[Rreg_index[opcode >> 4 & 0x0f]];
address += *postinc;
break;
case RM4:
postinc = &registers[Rreg_index[opcode >> 8 & 0x0f]];
address += *postinc;
break;
case RM6:
postinc = &registers[Rreg_index[opcode >> 12 & 0x0f]];
address += *postinc;
break;
case RD0:
postinc = &registers[Rreg_index[disp & 0x0f]];
address += *postinc;
break;
case RD2:
postinc = &registers[Rreg_index[disp >> 4 & 0x0f]];
address += *postinc;
break;
case SP:
address += registers[REG_SP >> 2];
break;
case SD8:
case SIMM8:
address += (int32_t) (int8_t) (disp & 0xff);
break;
case SD16:
address += (int32_t) (int16_t) (disp & 0xffff);
break;
case SD24:
tmp = disp << 8;
asm("asr 8,%0" : "=r"(tmp) : "0"(tmp));
address += tmp;
break;
case SIMM4_2:
tmp = opcode >> 4 & 0x0f;
tmp <<= 28;
asm("asr 28,%0" : "=r"(tmp) : "0"(tmp));
address += tmp;
break;
case IMM24:
address += disp & 0x00ffffff;
break;
case IMM32:
case IMM32_MEM:
case IMM32_HIGH8:
case IMM32_HIGH8_MEM:
address += disp;
break;
default:
return 0;
}
} while ((params >>= 8));
*_address = (void *) address;
*_postinc = postinc;
return 1;
}
/*
* determine the register that is acting as source/dest
*/
static int misalignment_reg(unsigned long *registers, unsigned params,
unsigned opcode, unsigned long disp,
unsigned long **_register)
{
params &= 0x7fffffff;
if (params & 0xffffff00)
return 0;
switch (params & 0xff) {
case DM0:
*_register = &registers[Dreg_index[opcode & 0x03]];
break;
case DM1:
*_register = &registers[Dreg_index[opcode >> 2 & 0x03]];
break;
case DM2:
*_register = &registers[Dreg_index[opcode >> 4 & 0x03]];
break;
case AM0:
*_register = &registers[Areg_index[opcode & 0x03]];
break;
case AM1:
*_register = &registers[Areg_index[opcode >> 2 & 0x03]];
break;
case AM2:
*_register = &registers[Areg_index[opcode >> 4 & 0x03]];
break;
case RM0:
*_register = &registers[Rreg_index[opcode & 0x0f]];
break;
case RM1:
*_register = &registers[Rreg_index[opcode >> 2 & 0x0f]];
break;
case RM2:
*_register = &registers[Rreg_index[opcode >> 4 & 0x0f]];
break;
case RM4:
*_register = &registers[Rreg_index[opcode >> 8 & 0x0f]];
break;
case RM6:
*_register = &registers[Rreg_index[opcode >> 12 & 0x0f]];
break;
case RD0:
*_register = &registers[Rreg_index[disp & 0x0f]];
break;
case RD2:
*_register = &registers[Rreg_index[disp >> 4 & 0x0f]];
break;
case SP:
*_register = &registers[REG_SP >> 2];
break;
default:
return 0;
}
return 1;
}
/*
* misalignment handler tests
*/
#ifdef CONFIG_TEST_MISALIGNMENT_HANDLER
static u8 __initdata testbuf[512] __attribute__((aligned(16))) = {
[257] = 0x11,
[258] = 0x22,
[259] = 0x33,
[260] = 0x44,
};
#define ASSERTCMP(X, OP, Y) \
do { \
if (unlikely(!((X) OP (Y)))) { \
printk(KERN_ERR "\n"); \
printk(KERN_ERR "MISALIGN: Assertion failed at line %u\n", \
__LINE__); \
printk(KERN_ERR "0x%lx " #OP " 0x%lx is false\n", \
(unsigned long)(X), (unsigned long)(Y)); \
BUG(); \
} \
} while(0)
static int __init test_misalignment(void)
{
register void *r asm("e0");
register u32 y asm("e1");
void *p = testbuf, *q;
u32 tmp, tmp2, x;
printk(KERN_NOTICE "==>test_misalignment() [testbuf=%p]\n", p);
p++;
printk(KERN_NOTICE "___ MOV (Am),Dn ___\n");
q = p + 256;
asm volatile("mov (%0),%1" : "+a"(q), "=d"(x));
ASSERTCMP(q, ==, p + 256);
ASSERTCMP(x, ==, 0x44332211);
printk(KERN_NOTICE "___ MOV (256,Am),Dn ___\n");
q = p;
asm volatile("mov (256,%0),%1" : "+a"(q), "=d"(x));
ASSERTCMP(q, ==, p);
ASSERTCMP(x, ==, 0x44332211);
printk(KERN_NOTICE "___ MOV (Di,Am),Dn ___\n");
tmp = 256;
q = p;
asm volatile("mov (%2,%0),%1" : "+a"(q), "=d"(x), "+d"(tmp));
ASSERTCMP(q, ==, p);
ASSERTCMP(x, ==, 0x44332211);
ASSERTCMP(tmp, ==, 256);
printk(KERN_NOTICE "___ MOV (256,Rm),Rn ___\n");
r = p;
asm volatile("mov (256,%0),%1" : "+r"(r), "=r"(y));
ASSERTCMP(r, ==, p);
ASSERTCMP(y, ==, 0x44332211);
printk(KERN_NOTICE "___ MOV (Rm+),Rn ___\n");
r = p + 256;
asm volatile("mov (%0+),%1" : "+r"(r), "=r"(y));
ASSERTCMP(r, ==, p + 256 + 4);
ASSERTCMP(y, ==, 0x44332211);
printk(KERN_NOTICE "___ MOV (Rm+,8),Rn ___\n");
r = p + 256;
asm volatile("mov (%0+,8),%1" : "+r"(r), "=r"(y));
ASSERTCMP(r, ==, p + 256 + 8);
ASSERTCMP(y, ==, 0x44332211);
printk(KERN_NOTICE "___ MOV (7,SP),Rn ___\n");
asm volatile(
"add -16,sp \n"
"mov +0x11,%0 \n"
"movbu %0,(7,sp) \n"
"mov +0x22,%0 \n"
"movbu %0,(8,sp) \n"
"mov +0x33,%0 \n"
"movbu %0,(9,sp) \n"
"mov +0x44,%0 \n"
"movbu %0,(10,sp) \n"
"mov (7,sp),%1 \n"
"add +16,sp \n"
: "+a"(q), "=d"(x));
ASSERTCMP(x, ==, 0x44332211);
printk(KERN_NOTICE "___ MOV (259,SP),Rn ___\n");
asm volatile(
"add -264,sp \n"
"mov +0x11,%0 \n"
"movbu %0,(259,sp) \n"
"mov +0x22,%0 \n"
"movbu %0,(260,sp) \n"
"mov +0x33,%0 \n"
"movbu %0,(261,sp) \n"
"mov +0x55,%0 \n"
"movbu %0,(262,sp) \n"
"mov (259,sp),%1 \n"
"add +264,sp \n"
: "+d"(tmp), "=d"(x));
ASSERTCMP(x, ==, 0x55332211);
printk(KERN_NOTICE "___ MOV (260,SP),Rn ___\n");
asm volatile(
"add -264,sp \n"
"mov +0x11,%0 \n"
"movbu %0,(260,sp) \n"
"mov +0x22,%0 \n"
"movbu %0,(261,sp) \n"
"mov +0x33,%0 \n"
"movbu %0,(262,sp) \n"
"mov +0x55,%0 \n"
"movbu %0,(263,sp) \n"
"mov (260,sp),%1 \n"
"add +264,sp \n"
: "+d"(tmp), "=d"(x));
ASSERTCMP(x, ==, 0x55332211);
printk(KERN_NOTICE "___ MOV_LNE ___\n");
tmp = 1;
tmp2 = 2;
q = p + 256;
asm volatile(
"setlb \n"
"mov %2,%3 \n"
"mov %1,%2 \n"
"cmp +0,%1 \n"
"mov_lne (%0+,4),%1"
: "+r"(q), "+d"(tmp), "+d"(tmp2), "=d"(x)
:
: "cc");
ASSERTCMP(q, ==, p + 256 + 12);
ASSERTCMP(x, ==, 0x44332211);
printk(KERN_NOTICE "___ MOV in SETLB ___\n");
tmp = 1;
tmp2 = 2;
q = p + 256;
asm volatile(
"setlb \n"
"mov %1,%3 \n"
"mov (%0+),%1 \n"
"cmp +0,%1 \n"
"lne "
: "+a"(q), "+d"(tmp), "+d"(tmp2), "=d"(x)
:
: "cc");
ASSERTCMP(q, ==, p + 256 + 8);
ASSERTCMP(x, ==, 0x44332211);
printk(KERN_NOTICE "<==test_misalignment()\n");
return 0;
}
arch_initcall(test_misalignment);
#endif /* CONFIG_TEST_MISALIGNMENT_HANDLER */