Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754131AbaDRSVl (ORCPT ); Fri, 18 Apr 2014 14:21:41 -0400 Received: from [207.46.100.130] ([207.46.100.130]:23810 "EHLO na01-by2-obe.outbound.protection.outlook.com" rhost-flags-FAIL-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1752940AbaDRSVb (ORCPT ); Fri, 18 Apr 2014 14:21:31 -0400 From: Ley Foon Tan To: , , CC: Ley Foon Tan , , Subject: [PATCH 05/28] nios2: Traps exception handling Date: Sat, 19 Apr 2014 02:19:07 +0800 Message-ID: <1397845149-3141-2-git-send-email-lftan@altera.com> X-Mailer: git-send-email 1.8.3.2 In-Reply-To: <1397845149-3141-1-git-send-email-lftan@altera.com> References: <1397824031-4892-1-git-send-email-lftan@altera.com> <1397845149-3141-1-git-send-email-lftan@altera.com> MIME-Version: 1.0 Content-Type: text/plain X-EOPAttributedMessage: 0 X-Forefront-Antispam-Report: CIP:66.35.236.232;CTRY:US;IPV:NLI;EFV:NLI;SFV:NSPM;SFS:(10019001)(6009001)(22564002)(43544003)(199002)(189002)(92726001)(4396001)(50466002)(2201001)(50226001)(92566001)(76482001)(33646001)(19580405001)(97736001)(42186004)(31966008)(16796002)(80022001)(86362001)(74502001)(48376002)(93916002)(74662001)(62966002)(76176999)(44976005)(84676001)(88136002)(19580395003)(6806004)(83322001)(80976001)(85852003)(50986999)(87286001)(87936001)(83072002)(2009001)(77982001)(79102001)(77156001)(99396002)(81342001)(81542001)(20776003)(89996001)(36756003)(47776003)(46102001)(2004002);DIR:OUT;SFP:1102;SCL:1;SRVR:BL2FFO11HUB005;H:SJ-ITEXEDGE02.altera.priv.altera.com;FPR:20A1D356.409A5389.7CD29676.42DB785A.20BB9;MLV:sfv;PTR:InfoDomainNonexistent;A:1;MX:1;LANG:en; X-OriginatorOrg: altera.onmicrosoft.com X-Forefront-PRVS: 018577E36E Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch contains traps exception handling. Signed-off-by: Ley Foon Tan --- arch/nios2/include/asm/traps.h | 19 ++ arch/nios2/kernel/insnemu.S | 592 +++++++++++++++++++++++++++++++++++++++++ arch/nios2/kernel/traps.c | 185 +++++++++++++ 3 files changed, 796 insertions(+) create mode 100644 arch/nios2/include/asm/traps.h create mode 100644 arch/nios2/kernel/insnemu.S create mode 100644 arch/nios2/kernel/traps.c diff --git a/arch/nios2/include/asm/traps.h b/arch/nios2/include/asm/traps.h new file mode 100644 index 0000000..82a48473280d870e813c6a298e51166f869c6487 --- /dev/null +++ b/arch/nios2/include/asm/traps.h @@ -0,0 +1,19 @@ +/* + * Copyright (C) 2011 Tobias Klauser + * Copyright (C) 2004 Microtronix Datacom Ltd. + * + * 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. + */ + +#ifndef _ASM_NIOS2_TRAPS_H +#define _ASM_NIOS2_TRAPS_H + +#define TRAP_ID_SYSCALL 0 + +#ifndef __ASSEMBLY__ +void _exception(int signo, struct pt_regs *regs, int code, unsigned long addr); +#endif + +#endif /* _ASM_NIOS2_TRAPS_H */ diff --git a/arch/nios2/kernel/insnemu.S b/arch/nios2/kernel/insnemu.S new file mode 100644 index 0000000..8a47a77d314538d2a1f82501c205970b2dea1f3c --- /dev/null +++ b/arch/nios2/kernel/insnemu.S @@ -0,0 +1,592 @@ +/* + * Copyright (C) 2003-2013 Altera Corporation + * All rights reserved. + * + * 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 . + */ + + +#include +#include + +.set noat +.set nobreak + +/* +* Explicitly allow the use of r1 (the assembler temporary register) +* within this code. This register is normally reserved for the use of +* the compiler. +*/ + +ENTRY(instruction_trap) + ldw r1, PT_R1(sp) // Restore registers + ldw r2, PT_R2(sp) + ldw r3, PT_R3(sp) + ldw r4, PT_R4(sp) + ldw r5, PT_R5(sp) + ldw r6, PT_R6(sp) + ldw r7, PT_R7(sp) + ldw r8, PT_R8(sp) + ldw r9, PT_R9(sp) + ldw r10, PT_R10(sp) + ldw r11, PT_R11(sp) + ldw r12, PT_R12(sp) + ldw r13, PT_R13(sp) + ldw r14, PT_R14(sp) + ldw r15, PT_R15(sp) + ldw ra, PT_RA(sp) + ldw fp, PT_FP(sp) + ldw gp, PT_GP(sp) + ldw et, PT_ESTATUS(sp) + wrctl estatus, et + ldw ea, PT_EA(sp) + ldw et, PT_SP(sp) /* backup sp in et */ + + addi sp, sp, PT_REGS_SIZE + + /* INSTRUCTION EMULATION + * --------------------- + * + * Nios II processors generate exceptions for unimplemented instructions. + * The routines below emulate these instructions. Depending on the + * processor core, the only instructions that might need to be emulated + * are div, divu, mul, muli, mulxss, mulxsu, and mulxuu. + * + * The emulations match the instructions, except for the following + * limitations: + * + * 1) The emulation routines do not emulate the use of the exception + * temporary register (et) as a source operand because the exception + * handler already has modified it. + * + * 2) The routines do not emulate the use of the stack pointer (sp) or + * the exception return address register (ea) as a destination because + * modifying these registers crashes the exception handler or the + * interrupted routine. + * + * Detailed Design + * --------------- + * + * The emulation routines expect the contents of integer registers r0-r31 + * to be on the stack at addresses sp, 4(sp), 8(sp), ... 124(sp). The + * routines retrieve source operands from the stack and modify the + * destination register's value on the stack prior to the end of the + * exception handler. Then all registers except the destination register + * are restored to their previous values. + * + * The instruction that causes the exception is found at address -4(ea). + * The instruction's OP and OPX fields identify the operation to be + * performed. + * + * One instruction, muli, is an I-type instruction that is identified by + * an OP field of 0x24. + * + * muli AAAAA,BBBBB,IIIIIIIIIIIIIIII,-0x24- + * 27 22 6 0 <-- LSB of field + * + * The remaining emulated instructions are R-type and have an OP field + * of 0x3a. Their OPX fields identify them. + * + * R-type AAAAA,BBBBB,CCCCC,XXXXXX,NNNNN,-0x3a- + * 27 22 17 11 6 0 <-- LSB of field + * + * + * Opcode Encoding. muli is identified by its OP value. Then OPX & 0x02 + * is used to differentiate between the division opcodes and the + * remaining multiplication opcodes. + * + * Instruction OP OPX OPX & 0x02 + * ----------- ---- ---- ---------- + * muli 0x24 + * divu 0x3a 0x24 0 + * div 0x3a 0x25 0 + * mul 0x3a 0x27 != 0 + * mulxuu 0x3a 0x07 != 0 + * mulxsu 0x3a 0x17 != 0 + * mulxss 0x3a 0x1f != 0 + */ + + + /* + * Save everything on the stack to make it easy for the emulation + * routines to retrieve the source register operands. + */ + + addi sp, sp, -128 + stw zero, 0(sp) /* Save zero on stack to avoid special case for r0. */ + stw r1, 4(sp) + stw r2, 8(sp) + stw r3, 12(sp) + stw r4, 16(sp) + stw r5, 20(sp) + stw r6, 24(sp) + stw r7, 28(sp) + stw r8, 32(sp) + stw r9, 36(sp) + stw r10, 40(sp) + stw r11, 44(sp) + stw r12, 48(sp) + stw r13, 52(sp) + stw r14, 56(sp) + stw r15, 60(sp) + stw r16, 64(sp) + stw r17, 68(sp) + stw r18, 72(sp) + stw r19, 76(sp) + stw r20, 80(sp) + stw r21, 84(sp) + stw r22, 88(sp) + stw r23, 92(sp) + /* Don't bother to save et. It's already been changed. */ + rdctl r5, estatus + stw r5, 100(sp) + + stw gp, 104(sp) + stw et, 108(sp) /* et containts previous sp value. */ + stw fp, 112(sp) + stw ea, 116(sp) + stw ra, 120(sp) + + + /* + * Split the instruction into its fields. We need 4*A, 4*B, and 4*C as + * offsets to the stack pointer for access to the stored register values. + */ + ldw r2,-4(ea) /* r2 = AAAAA,BBBBB,IIIIIIIIIIIIIIII,PPPPPP */ + roli r3, r2, 7 /* r3 = BBB,IIIIIIIIIIIIIIII,PPPPPP,AAAAA,BB */ + roli r4, r3, 3 /* r4 = IIIIIIIIIIIIIIII,PPPPPP,AAAAA,BBBBB */ + roli r5, r4, 2 /* r5 = IIIIIIIIIIIIII,PPPPPP,AAAAA,BBBBB,II */ + srai r4, r4, 16 /* r4 = (sign-extended) IMM16 */ + roli r6, r5, 5 /* r6 = XXXX,NNNNN,PPPPPP,AAAAA,BBBBB,CCCCC,XX */ + andi r2, r2, 0x3f /* r2 = 00000000000000000000000000,PPPPPP */ + andi r3, r3, 0x7c /* r3 = 0000000000000000000000000,AAAAA,00 */ + andi r5, r5, 0x7c /* r5 = 0000000000000000000000000,BBBBB,00 */ + andi r6, r6, 0x7c /* r6 = 0000000000000000000000000,CCCCC,00 */ + + /* Now + * r2 = OP + * r3 = 4*A + * r4 = IMM16 (sign extended) + * r5 = 4*B + * r6 = 4*C + */ + + /* + * Get the operands. + * + * It is necessary to check for muli because it uses an I-type + * instruction format, while the other instructions are have an R-type + * format. + * + * Prepare for either multiplication or division loop. + * They both loop 32 times. + */ + movi r14, 32 + + add r3, r3, sp /* r3 = address of A-operand. */ + ldw r3, 0(r3) /* r3 = A-operand. */ + movi r7, 0x24 /* muli opcode (I-type instruction format) */ + beq r2, r7, mul_immed /* muli doesn't use the B register as a source */ + + add r5, r5, sp /* r5 = address of B-operand. */ + ldw r5, 0(r5) /* r5 = B-operand. */ + /* r4 = SSSSSSSSSSSSSSSS,-----IMM16------ */ + /* IMM16 not needed, align OPX portion */ + /* r4 = SSSSSSSSSSSSSSSS,CCCCC,-OPX--,00000 */ + srli r4, r4, 5 /* r4 = 00000,SSSSSSSSSSSSSSSS,CCCCC,-OPX-- */ + andi r4, r4, 0x3f /* r4 = 00000000000000000000000000,-OPX-- */ + + /* Now + * r2 = OP + * r3 = src1 + * r5 = src2 + * r4 = OPX (no longer can be muli) + * r6 = 4*C + */ + + + /* + * Multiply or Divide? + */ + andi r7, r4, 0x02 /* For R-type multiply instructions, + OPX & 0x02 != 0 */ + bne r7, zero, multiply + + + /* DIVISION + * + * Divide an unsigned dividend by an unsigned divisor using + * a shift-and-subtract algorithm. The example below shows + * 43 div 7 = 6 for 8-bit integers. This classic algorithm uses a + * single register to store both the dividend and the quotient, + * allowing both values to be shifted with a single instruction. + * + * remainder dividend:quotient + * --------- ----------------- + * initialize 00000000 00101011: + * shift 00000000 0101011:_ + * remainder >= divisor? no 00000000 0101011:0 + * shift 00000000 101011:0_ + * remainder >= divisor? no 00000000 101011:00 + * shift 00000001 01011:00_ + * remainder >= divisor? no 00000001 01011:000 + * shift 00000010 1011:000_ + * remainder >= divisor? no 00000010 1011:0000 + * shift 00000101 011:0000_ + * remainder >= divisor? no 00000101 011:00000 + * shift 00001010 11:00000_ + * remainder >= divisor? yes 00001010 11:000001 + * remainder -= divisor - 00000111 + * ---------- + * 00000011 11:000001 + * shift 00000111 1:000001_ + * remainder >= divisor? yes 00000111 1:0000011 + * remainder -= divisor - 00000111 + * ---------- + * 00000000 1:0000011 + * shift 00000001 :0000011_ + * remainder >= divisor? no 00000001 :00000110 + * + * The quotient is 00000110. + */ + +divide: + /* + * Prepare for division by assuming the result + * is unsigned, and storing its "sign" as 0. + */ + movi r17, 0 + + + /* Which division opcode? */ + xori r7, r4, 0x25 /* OPX of div */ + bne r7, zero, unsigned_division + + + /* + * OPX is div. Determine and store the sign of the quotient. + * Then take the absolute value of both operands. + */ + xor r17, r3, r5 /* MSB contains sign of quotient */ + bge r3,zero,dividend_is_nonnegative + sub r3, zero, r3 /* -r3 */ +dividend_is_nonnegative: + bge r5, zero, divisor_is_nonnegative + sub r5, zero, r5 /* -r5 */ +divisor_is_nonnegative: + + +unsigned_division: + /* Initialize the unsigned-division loop. */ + movi r13, 0 /* remainder = 0 */ + + /* Now + * r3 = dividend : quotient + * r4 = 0x25 for div, 0x24 for divu + * r5 = divisor + * r13 = remainder + * r14 = loop counter (already initialized to 32) + * r17 = MSB contains sign of quotient + */ + + + /* + * for (count = 32; count > 0; --count) + * { + */ +divide_loop: + + /* + * Division: + * + * (remainder:dividend:quotient) <<= 1; + */ + slli r13, r13, 1 + cmplt r7, r3, zero /* r7 = MSB of r3 */ + or r13, r13, r7 + slli r3, r3, 1 + + + /* + * if (remainder >= divisor) + * { + * set LSB of quotient + * remainder -= divisor; + * } + */ + bltu r13, r5, div_skip + ori r3, r3, 1 + sub r13, r13, r5 +div_skip: + + /* + * } + */ + subi r14, r14, 1 + bne r14, zero, divide_loop + + + /* Now + * r3 = quotient + * r4 = 0x25 for div, 0x24 for divu + * r6 = 4*C + * r17 = MSB contains sign of quotient + */ + + + /* + * Conditionally negate signed quotient. If quotient is unsigned, + * the sign already is initialized to 0. + */ + bge r17, zero, quotient_is_nonnegative + sub r3, zero, r3 /* -r3 */ + quotient_is_nonnegative: + + + /* + * Final quotient is in r3. + */ + add r6, r6, sp + stw r3, 0(r6) /* write quotient to stack */ + br restore_registers + + + + + /* MULTIPLICATION + * + * A "product" is the number that one gets by summing a "multiplicand" + * several times. The "multiplier" specifies the number of copies of the + * multiplicand that are summed. + * + * Actual multiplication algorithms don't use repeated addition, however. + * Shift-and-add algorithms get the same answer as repeated addition, and + * they are faster. To compute the lower half of a product (pppp below) + * one shifts the product left before adding in each of the partial + * products (a * mmmm) through (d * mmmm). + * + * To compute the upper half of a product (PPPP below), one adds in the + * partial products (d * mmmm) through (a * mmmm), each time following + * the add by a right shift of the product. + * + * mmmm + * * abcd + * ------ + * #### = d * mmmm + * #### = c * mmmm + * #### = b * mmmm + * #### = a * mmmm + * -------- + * PPPPpppp + * + * The example above shows 4 partial products. Computing actual Nios II + * products requires 32 partials. + * + * It is possible to compute the result of mulxsu from the result of + * mulxuu because the only difference between the results of these two + * opcodes is the value of the partial product associated with the sign + * bit of rA. + * + * mulxsu = mulxuu - (rA < 0) ? rB : 0; + * + * It is possible to compute the result of mulxss from the result of + * mulxsu because the only difference between the results of these two + * opcodes is the value of the partial product associated with the sign + * bit of rB. + * + * mulxss = mulxsu - (rB < 0) ? rA : 0; + * + */ + +mul_immed: + /* Opcode is muli. Change it into mul for remainder of algorithm. */ + mov r6, r5 /* Field B is dest register, not field C. */ + mov r5, r4 /* Field IMM16 is src2, not field B. */ + movi r4, 0x27 /* OPX of mul is 0x27 */ + +multiply: + /* Initialize the multiplication loop. */ + movi r9, 0 /* mul_product = 0 */ + movi r10, 0 /* mulxuu_product = 0 */ + mov r11, r5 /* save original multiplier for mulxsu and mulxss */ + mov r12, r5 /* mulxuu_multiplier (will be shifted) */ + movi r16, 1 /* used to create "rori B,A,1" from "ror B,A,r16" */ + + /* Now + * r3 = multiplicand + * r5 = mul_multiplier + * r6 = 4 * dest_register (used later as offset to sp) + * r7 = temp + * r9 = mul_product + * r10 = mulxuu_product + * r11 = original multiplier + * r12 = mulxuu_multiplier + * r14 = loop counter (already initialized) + * r16 = 1 + */ + + + /* + * for (count = 32; count > 0; --count) + * { + */ +multiply_loop: + + /* + * mul_product <<= 1; + * lsb = multiplier & 1; + */ + slli r9, r9, 1 + andi r7, r12, 1 + + /* + * if (lsb == 1) + * { + * mulxuu_product += multiplicand; + * } + */ + beq r7, zero, mulx_skip + add r10, r10, r3 + cmpltu r7, r10, r3 /* Save the carry from the MSB of mulxuu_product. */ + ror r7, r7, r16 /* r7 = 0x80000000 on carry, or else 0x00000000 */ +mulx_skip: + + /* + * if (MSB of mul_multiplier == 1) + * { + * mul_product += multiplicand; + * } + */ + bge r5, zero, mul_skip + add r9, r9, r3 +mul_skip: + + /* + * mulxuu_product >>= 1; logical shift + * mul_multiplier <<= 1; done with MSB + * mulx_multiplier >>= 1; done with LSB + */ + srli r10, r10, 1 + or r10, r10, r7 /* OR in the saved carry bit. */ + slli r5, r5, 1 + srli r12, r12, 1 + + + /* + * } + */ + subi r14, r14, 1 + bne r14, zero, multiply_loop + + + /* + * Multiply emulation loop done. + */ + + /* Now + * r3 = multiplicand + * r4 = OPX + * r6 = 4 * dest_register (used later as offset to sp) + * r7 = temp + * r9 = mul_product + * r10 = mulxuu_product + * r11 = original multiplier + */ + + + /* Calculate address for result from 4 * dest_register */ + add r6, r6, sp + + + /* + * Select/compute the result based on OPX. + */ + + + /* OPX == mul? Then store. */ + xori r7, r4, 0x27 + beq r7, zero, store_product + + /* It's one of the mulx.. opcodes. Move over the result. */ + mov r9, r10 + + /* OPX == mulxuu? Then store. */ + xori r7, r4, 0x07 + beq r7, zero, store_product + + /* Compute mulxsu + * + * mulxsu = mulxuu - (rA < 0) ? rB : 0; + */ + bge r3, zero, mulxsu_skip + sub r9, r9, r11 +mulxsu_skip: + + /* OPX == mulxsu? Then store. */ + xori r7, r4, 0x17 + beq r7, zero, store_product + + /* Compute mulxss + * + * mulxss = mulxsu - (rB < 0) ? rA : 0; + */ + bge r11,zero,mulxss_skip + sub r9, r9, r3 +mulxss_skip: + /* At this point, assume that OPX is mulxss, so store*/ + + +store_product: + stw r9, 0(r6) + + +restore_registers: + /* No need to restore r0. */ + ldw r5, 100(sp) + wrctl estatus, r5 + + ldw r1, 4(sp) + ldw r2, 8(sp) + ldw r3, 12(sp) + ldw r4, 16(sp) + ldw r5, 20(sp) + ldw r6, 24(sp) + ldw r7, 28(sp) + ldw r8, 32(sp) + ldw r9, 36(sp) + ldw r10, 40(sp) + ldw r11, 44(sp) + ldw r12, 48(sp) + ldw r13, 52(sp) + ldw r14, 56(sp) + ldw r15, 60(sp) + ldw r16, 64(sp) + ldw r17, 68(sp) + ldw r18, 72(sp) + ldw r19, 76(sp) + ldw r20, 80(sp) + ldw r21, 84(sp) + ldw r22, 88(sp) + ldw r23, 92(sp) + /* Does not need to restore et */ + ldw gp, 104(sp) + + ldw fp, 112(sp) + ldw ea, 116(sp) + ldw ra, 120(sp) + ldw sp, 108(sp) /* last restore sp */ + eret + +.set at +.set break diff --git a/arch/nios2/kernel/traps.c b/arch/nios2/kernel/traps.c new file mode 100644 index 0000000..53ddf8d --- /dev/null +++ b/arch/nios2/kernel/traps.c @@ -0,0 +1,185 @@ +/* + * Hardware exception handling + * + * Copyright (C) 2010 Tobias Klauser + * Copyright (C) 2004 Microtronix Datacom Ltd. + * Copyright (C) 2001 Vic Phillips + * + * 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 +#include +#include +#include +#include +#include + +#include +#include + + +static DEFINE_SPINLOCK(die_lock); + +void die(const char *str, struct pt_regs *regs, long err) +{ + console_verbose(); + spin_lock_irq(&die_lock); + pr_warn("Oops: %s, sig: %ld\n", str, err); + show_regs(regs); + spin_unlock_irq(&die_lock); + /* + * do_exit() should take care of panic'ing from an interrupt + * context so we don't handle it here + */ + do_exit(err); +} + +void _exception(int signo, struct pt_regs *regs, int code, unsigned long addr) +{ + siginfo_t info; + + if (!user_mode(regs)) + die("Exception in kernel mode", regs, signo); + + info.si_signo = signo; + info.si_errno = 0; + info.si_code = code; + info.si_addr = (void __user *) addr; + force_sig_info(signo, &info, current); +} + +/* + * The show_stack is an external API which we do not use ourselves. + */ + +int kstack_depth_to_print = 48; + +void show_stack(struct task_struct *task, unsigned long *stack) +{ + unsigned long *endstack, addr; + int i; + + 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); + + pr_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) + pr_emerg("\n "); + pr_emerg(" %08lx", *stack++); + } + + pr_emerg("\nCall Trace:"); + i = 0; + while (stack + 1 <= endstack) { + addr = *stack++; + /* + * 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 (((addr >= (unsigned long) _stext) && + (addr <= (unsigned long) _etext))) { + if (i % 4 == 0) + pr_emerg("\n "); + pr_emerg(" [<%08lx>]", addr); + i++; + } + } + pr_emerg("\n"); +} + +void __init trap_init(void) +{ + /* Nothing to do here */ +} + +/* Breakpoint handler */ +asmlinkage void breakpoint_c(struct pt_regs *fp) +{ + /* + * The breakpoint entry code has moved the PC on by 4 bytes, so we must + * move it back. This could be done on the host but we do it here + * because monitor.S of JTAG gdbserver does it too. + */ + fp->ea -= 4; + _exception(SIGTRAP, fp, TRAP_BRKPT, fp->ea); +} + +#ifndef CONFIG_ALIGNMENT_TRAP +/* Alignment exception handler */ +asmlinkage void handle_unaligned_c(struct pt_regs *fp, int cause) +{ + unsigned long addr = RDCTL(CTL_BADADDR); + + cause >>= 2; + fp->ea -= 4; + + if (fixup_exception(fp)) + return; + + if (!user_mode(fp)) { + pr_alert("Unaligned access from kernel mode, this might be a hardware\n"); + pr_alert("problem, dump registers and restart the instruction\n"); + pr_alert(" BADADDR 0x%08lx\n", addr); + pr_alert(" cause %d\n", cause); + pr_alert(" op-code 0x%08lx\n", *(unsigned long *)(fp->ea)); + show_regs(fp); + return; + } + + _exception(SIGBUS, fp, BUS_ADRALN, addr); +} +#endif /* CONFIG_ALIGNMENT_TRAP */ + +/* Illegal instruction handler */ +asmlinkage void handle_illegal_c(struct pt_regs *fp) +{ + fp->ea -= 4; + _exception(SIGILL, fp, ILL_ILLOPC, fp->ea); +} + +/* Supervisor instruction handler */ +asmlinkage void handle_supervisor_instr(struct pt_regs *fp) +{ + fp->ea -= 4; + _exception(SIGILL, fp, ILL_PRVOPC, fp->ea); +} + +/* Division error handler */ +asmlinkage void handle_diverror_c(struct pt_regs *fp) +{ + fp->ea -= 4; + _exception(SIGFPE, fp, FPE_INTDIV, fp->ea); +} + +/* Unhandled exception handler */ +asmlinkage void unhandled_exception(struct pt_regs *regs, int cause) +{ + unsigned long addr = RDCTL(CTL_BADADDR); + + cause /= 4; + + pr_emerg("Unhandled exception #%d in %s mode (badaddr=0x%08lx)\n", + cause, user_mode(regs) ? "user" : "kernel", addr); + + regs->ea -= 4; + show_regs(regs); + + pr_emerg("opcode: 0x%08lx\n", *(unsigned long *)(regs->ea)); +} -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/