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-rw-r--r--arch/tile/kernel/traps.c421
1 files changed, 0 insertions, 421 deletions
diff --git a/arch/tile/kernel/traps.c b/arch/tile/kernel/traps.c
deleted file mode 100644
index 83a7186198d7..000000000000
--- a/arch/tile/kernel/traps.c
+++ /dev/null
@@ -1,421 +0,0 @@
-/*
- * Copyright 2010 Tilera 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, version 2.
- *
- * 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, GOOD TITLE or
- * NON INFRINGEMENT. See the GNU General Public License for
- * more details.
- */
-
-#include <linux/sched.h>
-#include <linux/sched/debug.h>
-#include <linux/kernel.h>
-#include <linux/kprobes.h>
-#include <linux/kdebug.h>
-#include <linux/module.h>
-#include <linux/reboot.h>
-#include <linux/uaccess.h>
-#include <linux/ptrace.h>
-#include <linux/hardirq.h>
-#include <linux/nmi.h>
-#include <asm/stack.h>
-#include <asm/traps.h>
-#include <asm/setup.h>
-
-#include <arch/interrupts.h>
-#include <arch/spr_def.h>
-#include <arch/opcode.h>
-
-void __init trap_init(void)
-{
- /* Nothing needed here since we link code at .intrpt */
-}
-
-int unaligned_fixup = 1;
-
-static int __init setup_unaligned_fixup(char *str)
-{
- /*
- * Say "=-1" to completely disable it. If you just do "=0", we
- * will still parse the instruction, then fire a SIGBUS with
- * the correct address from inside the single_step code.
- */
- if (kstrtoint(str, 0, &unaligned_fixup) != 0)
- return 0;
-
- pr_info("Fixups for unaligned data accesses are %s\n",
- unaligned_fixup >= 0 ?
- (unaligned_fixup ? "enabled" : "disabled") :
- "completely disabled");
- return 1;
-}
-__setup("unaligned_fixup=", setup_unaligned_fixup);
-
-#if CHIP_HAS_TILE_DMA()
-
-static int dma_disabled;
-
-static int __init nodma(char *str)
-{
- pr_info("User-space DMA is disabled\n");
- dma_disabled = 1;
- return 1;
-}
-__setup("nodma", nodma);
-
-/* How to decode SPR_GPV_REASON */
-#define IRET_ERROR (1U << 31)
-#define MT_ERROR (1U << 30)
-#define MF_ERROR (1U << 29)
-#define SPR_INDEX ((1U << 15) - 1)
-#define SPR_MPL_SHIFT 9 /* starting bit position for MPL encoded in SPR */
-
-/*
- * See if this GPV is just to notify the kernel of SPR use and we can
- * retry the user instruction after adjusting some MPLs suitably.
- */
-static int retry_gpv(unsigned int gpv_reason)
-{
- int mpl;
-
- if (gpv_reason & IRET_ERROR)
- return 0;
-
- BUG_ON((gpv_reason & (MT_ERROR|MF_ERROR)) == 0);
- mpl = (gpv_reason & SPR_INDEX) >> SPR_MPL_SHIFT;
- if (mpl == INT_DMA_NOTIFY && !dma_disabled) {
- /* User is turning on DMA. Allow it and retry. */
- printk(KERN_DEBUG "Process %d/%s is now enabled for DMA\n",
- current->pid, current->comm);
- BUG_ON(current->thread.tile_dma_state.enabled);
- current->thread.tile_dma_state.enabled = 1;
- grant_dma_mpls();
- return 1;
- }
-
- return 0;
-}
-
-#endif /* CHIP_HAS_TILE_DMA() */
-
-extern tile_bundle_bits bpt_code;
-
-asm(".pushsection .rodata.bpt_code,\"a\";"
- ".align 8;"
- "bpt_code: bpt;"
- ".size bpt_code,.-bpt_code;"
- ".popsection");
-
-static int special_ill(tile_bundle_bits bundle, int *sigp, int *codep)
-{
- int sig, code, maxcode;
-
- if (bundle == bpt_code) {
- *sigp = SIGTRAP;
- *codep = TRAP_BRKPT;
- return 1;
- }
-
- /* If it's a "raise" bundle, then "ill" must be in pipe X1. */
-#ifdef __tilegx__
- if ((bundle & TILEGX_BUNDLE_MODE_MASK) != 0)
- return 0;
- if (get_Opcode_X1(bundle) != RRR_0_OPCODE_X1)
- return 0;
- if (get_RRROpcodeExtension_X1(bundle) != UNARY_RRR_0_OPCODE_X1)
- return 0;
- if (get_UnaryOpcodeExtension_X1(bundle) != ILL_UNARY_OPCODE_X1)
- return 0;
-#else
- if (bundle & TILEPRO_BUNDLE_Y_ENCODING_MASK)
- return 0;
- if (get_Opcode_X1(bundle) != SHUN_0_OPCODE_X1)
- return 0;
- if (get_UnShOpcodeExtension_X1(bundle) != UN_0_SHUN_0_OPCODE_X1)
- return 0;
- if (get_UnOpcodeExtension_X1(bundle) != ILL_UN_0_SHUN_0_OPCODE_X1)
- return 0;
-#endif
-
- /* Check that the magic distinguishers are set to mean "raise". */
- if (get_Dest_X1(bundle) != 29 || get_SrcA_X1(bundle) != 37)
- return 0;
-
- /* There must be an "addli zero, zero, VAL" in X0. */
- if (get_Opcode_X0(bundle) != ADDLI_OPCODE_X0)
- return 0;
- if (get_Dest_X0(bundle) != TREG_ZERO)
- return 0;
- if (get_SrcA_X0(bundle) != TREG_ZERO)
- return 0;
-
- /*
- * Validate the proposed signal number and si_code value.
- * Note that we embed these in the static instruction itself
- * so that we perturb the register state as little as possible
- * at the time of the actual fault; it's unlikely you'd ever
- * need to dynamically choose which kind of fault to raise
- * from user space.
- */
- sig = get_Imm16_X0(bundle) & 0x3f;
- switch (sig) {
- case SIGILL:
- maxcode = NSIGILL;
- break;
- case SIGFPE:
- maxcode = NSIGFPE;
- break;
- case SIGSEGV:
- maxcode = NSIGSEGV;
- break;
- case SIGBUS:
- maxcode = NSIGBUS;
- break;
- case SIGTRAP:
- maxcode = NSIGTRAP;
- break;
- default:
- return 0;
- }
- code = (get_Imm16_X0(bundle) >> 6) & 0xf;
- if (code <= 0 || code > maxcode)
- return 0;
-
- /* Make it the requested signal. */
- *sigp = sig;
- *codep = code;
- return 1;
-}
-
-static const char *const int_name[] = {
- [INT_MEM_ERROR] = "Memory error",
- [INT_ILL] = "Illegal instruction",
- [INT_GPV] = "General protection violation",
- [INT_UDN_ACCESS] = "UDN access",
- [INT_IDN_ACCESS] = "IDN access",
-#if CHIP_HAS_SN()
- [INT_SN_ACCESS] = "SN access",
-#endif
- [INT_SWINT_3] = "Software interrupt 3",
- [INT_SWINT_2] = "Software interrupt 2",
- [INT_SWINT_0] = "Software interrupt 0",
- [INT_UNALIGN_DATA] = "Unaligned data",
- [INT_DOUBLE_FAULT] = "Double fault",
-#ifdef __tilegx__
- [INT_ILL_TRANS] = "Illegal virtual address",
-#endif
-};
-
-static int do_bpt(struct pt_regs *regs)
-{
- unsigned long bundle, bcode, bpt;
-
- bundle = *(unsigned long *)instruction_pointer(regs);
-
- /*
- * bpt shoule be { bpt; nop }, which is 0x286a44ae51485000ULL.
- * we encode the unused least significant bits for other purpose.
- */
- bpt = bundle & ~((1ULL << 12) - 1);
- if (bpt != TILE_BPT_BUNDLE)
- return 0;
-
- bcode = bundle & ((1ULL << 12) - 1);
- /*
- * notify the kprobe handlers, if instruction is likely to
- * pertain to them.
- */
- switch (bcode) {
- /* breakpoint_insn */
- case 0:
- notify_die(DIE_BREAK, "debug", regs, bundle,
- INT_ILL, SIGTRAP);
- break;
- /* compiled_bpt */
- case DIE_COMPILED_BPT:
- notify_die(DIE_COMPILED_BPT, "debug", regs, bundle,
- INT_ILL, SIGTRAP);
- break;
- /* breakpoint2_insn */
- case DIE_SSTEPBP:
- notify_die(DIE_SSTEPBP, "single_step", regs, bundle,
- INT_ILL, SIGTRAP);
- break;
- default:
- return 0;
- }
-
- return 1;
-}
-
-void __kprobes do_trap(struct pt_regs *regs, int fault_num,
- unsigned long reason)
-{
- siginfo_t info;
- int signo, code;
- unsigned long address = 0;
- tile_bundle_bits instr;
- int is_kernel = !user_mode(regs);
-
- clear_siginfo(&info);
-
- /* Handle breakpoints, etc. */
- if (is_kernel && fault_num == INT_ILL && do_bpt(regs))
- return;
-
- /* Re-enable interrupts, if they were previously enabled. */
- if (!(regs->flags & PT_FLAGS_DISABLE_IRQ))
- local_irq_enable();
-
- /*
- * If it hits in kernel mode and we can't fix it up, just exit the
- * current process and hope for the best.
- */
- if (is_kernel) {
- const char *name;
- char buf[100];
- if (fixup_exception(regs)) /* ILL_TRANS or UNALIGN_DATA */
- return;
- if (fault_num >= 0 &&
- fault_num < ARRAY_SIZE(int_name) &&
- int_name[fault_num] != NULL)
- name = int_name[fault_num];
- else
- name = "Unknown interrupt";
- if (fault_num == INT_GPV)
- snprintf(buf, sizeof(buf), "; GPV_REASON %#lx", reason);
-#ifdef __tilegx__
- else if (fault_num == INT_ILL_TRANS)
- snprintf(buf, sizeof(buf), "; address %#lx", reason);
-#endif
- else
- buf[0] = '\0';
- pr_alert("Kernel took bad trap %d (%s) at PC %#lx%s\n",
- fault_num, name, regs->pc, buf);
- show_regs(regs);
- do_exit(SIGKILL); /* FIXME: implement i386 die() */
- }
-
- switch (fault_num) {
- case INT_MEM_ERROR:
- signo = SIGBUS;
- code = BUS_OBJERR;
- break;
- case INT_ILL:
- if (copy_from_user(&instr, (void __user *)regs->pc,
- sizeof(instr))) {
- pr_err("Unreadable instruction for INT_ILL: %#lx\n",
- regs->pc);
- do_exit(SIGKILL);
- }
- if (!special_ill(instr, &signo, &code)) {
- signo = SIGILL;
- code = ILL_ILLOPC;
- }
- address = regs->pc;
- break;
- case INT_GPV:
-#if CHIP_HAS_TILE_DMA()
- if (retry_gpv(reason))
- return;
-#endif
- /*FALLTHROUGH*/
- case INT_UDN_ACCESS:
- case INT_IDN_ACCESS:
-#if CHIP_HAS_SN()
- case INT_SN_ACCESS:
-#endif
- signo = SIGILL;
- code = ILL_PRVREG;
- address = regs->pc;
- break;
- case INT_SWINT_3:
- case INT_SWINT_2:
- case INT_SWINT_0:
- signo = SIGILL;
- code = ILL_ILLTRP;
- address = regs->pc;
- break;
- case INT_UNALIGN_DATA:
-#ifndef __tilegx__ /* Emulated support for single step debugging */
- if (unaligned_fixup >= 0) {
- struct single_step_state *state =
- current_thread_info()->step_state;
- if (!state ||
- (void __user *)(regs->pc) != state->buffer) {
- single_step_once(regs);
- return;
- }
- }
-#endif
- signo = SIGBUS;
- code = BUS_ADRALN;
- address = 0;
- break;
- case INT_DOUBLE_FAULT:
- /*
- * For double fault, "reason" is actually passed as
- * SYSTEM_SAVE_K_2, the hypervisor's double-fault info, so
- * we can provide the original fault number rather than
- * the uninteresting "INT_DOUBLE_FAULT" so the user can
- * learn what actually struck while PL0 ICS was set.
- */
- fault_num = reason;
- signo = SIGILL;
- code = ILL_DBLFLT;
- address = regs->pc;
- break;
-#ifdef __tilegx__
- case INT_ILL_TRANS: {
- /* Avoid a hardware erratum with the return address stack. */
- fill_ra_stack();
-
- signo = SIGSEGV;
- address = reason;
- code = SEGV_MAPERR;
- break;
- }
-#endif
- default:
- panic("Unexpected do_trap interrupt number %d", fault_num);
- }
-
- info.si_signo = signo;
- info.si_code = code;
- info.si_addr = (void __user *)address;
- if (signo == SIGILL)
- info.si_trapno = fault_num;
- if (signo != SIGTRAP)
- trace_unhandled_signal("trap", regs, address, signo);
- force_sig_info(signo, &info, current);
-}
-
-void do_nmi(struct pt_regs *regs, int fault_num, unsigned long reason)
-{
- nmi_enter();
- switch (reason) {
-#ifdef arch_trigger_cpumask_backtrace
- case TILE_NMI_DUMP_STACK:
- nmi_cpu_backtrace(regs);
- break;
-#endif
- default:
- panic("Unexpected do_nmi type %ld", reason);
- }
- nmi_exit();
-}
-
-/* Deprecated function currently only used here. */
-extern void _dump_stack(int dummy, ulong pc, ulong lr, ulong sp, ulong r52);
-
-void kernel_double_fault(int dummy, ulong pc, ulong lr, ulong sp, ulong r52)
-{
- _dump_stack(dummy, pc, lr, sp, r52);
- pr_emerg("Double fault: exiting\n");
- machine_halt();
-}
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