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author | Vineet Gupta <vgupta@synopsys.com> | 2013-01-18 09:42:18 (GMT) |
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committer | Vineet Gupta <vgupta@synopsys.com> | 2013-02-11 14:30:37 (GMT) |
commit | 054419ed8405da7aa93f88f698d696980efd3e37 (patch) | |
tree | 16b0376000cd0383eb8c5c064984c5c414042551 /arch/arc/kernel | |
parent | bacdf4809afade180a8f2171adb4cf7ec715d139 (diff) | |
download | linux-fsl-qoriq-054419ed8405da7aa93f88f698d696980efd3e37.tar.xz |
ARC: Non-MMU Exception Handling
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Diffstat (limited to 'arch/arc/kernel')
-rw-r--r-- | arch/arc/kernel/traps.c | 125 |
1 files changed, 125 insertions, 0 deletions
diff --git a/arch/arc/kernel/traps.c b/arch/arc/kernel/traps.c new file mode 100644 index 0000000..fd2457ce --- /dev/null +++ b/arch/arc/kernel/traps.c @@ -0,0 +1,125 @@ +/* + * Traps/Non-MMU Exception handling for ARC + * + * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * Rahul Trivedi: Codito Technologies 2004 + */ + +#include <linux/sched.h> +#include <linux/kdebug.h> +#include <linux/uaccess.h> +#include <asm/ptrace.h> +#include <asm/setup.h> + +void __init trap_init(void) +{ + return; +} + +void die(const char *str, struct pt_regs *regs, unsigned long address, + unsigned long cause_reg) +{ + show_kernel_fault_diag(str, regs, address, cause_reg); + + /* DEAD END */ + __asm__("flag 1"); +} + +/* + * Helper called for bulk of exceptions NOT needing specific handling + * -for user faults enqueues requested signal + * -for kernel, chk if due to copy_(to|from)_user, otherwise die() + */ +static noinline int handle_exception(unsigned long cause, char *str, + struct pt_regs *regs, siginfo_t *info) +{ + if (user_mode(regs)) { + struct task_struct *tsk = current; + + tsk->thread.fault_address = (__force unsigned int)info->si_addr; + tsk->thread.cause_code = cause; + + force_sig_info(info->si_signo, info, tsk); + + } else { + /* If not due to copy_(to|from)_user, we are doomed */ + if (fixup_exception(regs)) + return 0; + + die(str, regs, (unsigned long)info->si_addr, cause); + } + + return 1; +} + +#define DO_ERROR_INFO(signr, str, name, sicode) \ +int name(unsigned long cause, unsigned long address, struct pt_regs *regs) \ +{ \ + siginfo_t info = { \ + .si_signo = signr, \ + .si_errno = 0, \ + .si_code = sicode, \ + .si_addr = (void __user *)address, \ + }; \ + return handle_exception(cause, str, regs, &info);\ +} + +/* + * Entry points for exceptions NOT needing specific handling + */ +DO_ERROR_INFO(SIGILL, "Priv Op/Disabled Extn", do_privilege_fault, ILL_PRVOPC) +DO_ERROR_INFO(SIGILL, "Invalid Extn Insn", do_extension_fault, ILL_ILLOPC) +DO_ERROR_INFO(SIGILL, "Illegal Insn (or Seq)", insterror_is_error, ILL_ILLOPC) +DO_ERROR_INFO(SIGBUS, "Invalid Mem Access", do_memory_error, BUS_ADRERR) +DO_ERROR_INFO(SIGTRAP, "Breakpoint Set", trap_is_brkpt, TRAP_BRKPT) + +DO_ERROR_INFO(SIGSEGV, "Misaligned Access", do_misaligned_access, SEGV_ACCERR) + +/* + * Entry point for miscll errors such as Nested Exceptions + * -Duplicate TLB entry is handled seperately though + */ +void do_machine_check_fault(unsigned long cause, unsigned long address, + struct pt_regs *regs) +{ + die("Machine Check Exception", regs, address, cause); +} + +/* + * Entry point for traps induced by ARCompact TRAP_S <n> insn + * This is same family as TRAP0/SWI insn (use the same vector). + * The only difference being SWI insn take no operand, while TRAP_S does + * which reflects in ECR Reg as 8 bit param. + * Thus TRAP_S <n> can be used for specific purpose + * -1 used for software breakpointing (gdb) + * -2 used by kprobes + */ +void do_non_swi_trap(unsigned long cause, unsigned long address, + struct pt_regs *regs) +{ + unsigned int param = cause & 0xff; + + switch (param) { + case 1: + trap_is_brkpt(cause, address, regs); + break; + + default: + break; + } +} + +/* + * Entry point for Instruction Error Exception + */ +void do_insterror_or_kprobe(unsigned long cause, + unsigned long address, + struct pt_regs *regs) +{ + insterror_is_error(cause, address, regs); +} |