1 /* 2 * Copyright (C) 2012 ARM Ltd. 3 * 4 * This program is free software; you can redistribute it and/or modify 5 * it under the terms of the GNU General Public License version 2 as 6 * published by the Free Software Foundation. 7 * 8 * This program is distributed in the hope that it will be useful, 9 * but WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 11 * GNU General Public License for more details. 12 * 13 * You should have received a copy of the GNU General Public License 14 * along with this program. If not, see <http://www.gnu.org/licenses/>. 15 */ 16 #ifndef __ASM_DEBUG_MONITORS_H 17 #define __ASM_DEBUG_MONITORS_H 18 19 #ifdef __KERNEL__ 20 21 #include <linux/errno.h> 22 #include <linux/types.h> 23 #include <asm/brk-imm.h> 24 #include <asm/esr.h> 25 #include <asm/insn.h> 26 #include <asm/ptrace.h> 27 28 /* Low-level stepping controls. */ 29 #define DBG_MDSCR_SS (1 << 0) 30 #define DBG_SPSR_SS (1 << 21) 31 32 /* MDSCR_EL1 enabling bits */ 33 #define DBG_MDSCR_KDE (1 << 13) 34 #define DBG_MDSCR_MDE (1 << 15) 35 #define DBG_MDSCR_MASK ~(DBG_MDSCR_KDE | DBG_MDSCR_MDE) 36 37 #define DBG_ESR_EVT(x) (((x) >> 27) & 0x7) 38 39 /* AArch64 */ 40 #define DBG_ESR_EVT_HWBP 0x0 41 #define DBG_ESR_EVT_HWSS 0x1 42 #define DBG_ESR_EVT_HWWP 0x2 43 #define DBG_ESR_EVT_BRK 0x6 44 45 /* 46 * Break point instruction encoding 47 */ 48 #define BREAK_INSTR_SIZE AARCH64_INSN_SIZE 49 50 /* 51 * BRK instruction encoding 52 * The #imm16 value should be placed at bits[20:5] within BRK ins 53 */ 54 #define AARCH64_BREAK_MON 0xd4200000 55 56 /* 57 * BRK instruction for provoking a fault on purpose 58 * Unlike kgdb, #imm16 value with unallocated handler is used for faulting. 59 */ 60 #define AARCH64_BREAK_FAULT (AARCH64_BREAK_MON | (FAULT_BRK_IMM << 5)) 61 62 #define AARCH64_BREAK_KGDB_DYN_DBG \ 63 (AARCH64_BREAK_MON | (KGDB_DYN_DBG_BRK_IMM << 5)) 64 #define KGDB_DYN_BRK_INS_BYTE(x) \ 65 ((AARCH64_BREAK_KGDB_DYN_DBG >> (8 * (x))) & 0xff) 66 67 #define CACHE_FLUSH_IS_SAFE 1 68 69 /* AArch32 */ 70 #define DBG_ESR_EVT_BKPT 0x4 71 #define DBG_ESR_EVT_VECC 0x5 72 73 #define AARCH32_BREAK_ARM 0x07f001f0 74 #define AARCH32_BREAK_THUMB 0xde01 75 #define AARCH32_BREAK_THUMB2_LO 0xf7f0 76 #define AARCH32_BREAK_THUMB2_HI 0xa000 77 78 #ifndef __ASSEMBLY__ 79 struct task_struct; 80 81 #define DBG_ARCH_ID_RESERVED 0 /* In case of ptrace ABI updates. */ 82 83 #define DBG_HOOK_HANDLED 0 84 #define DBG_HOOK_ERROR 1 85 86 struct step_hook { 87 struct list_head node; 88 int (*fn)(struct pt_regs *regs, unsigned int esr); 89 }; 90 91 void register_step_hook(struct step_hook *hook); 92 void unregister_step_hook(struct step_hook *hook); 93 94 struct break_hook { 95 struct list_head node; 96 u32 esr_val; 97 u32 esr_mask; 98 int (*fn)(struct pt_regs *regs, unsigned int esr); 99 }; 100 101 void register_break_hook(struct break_hook *hook); 102 void unregister_break_hook(struct break_hook *hook); 103 104 u8 debug_monitors_arch(void); 105 106 enum dbg_active_el { 107 DBG_ACTIVE_EL0 = 0, 108 DBG_ACTIVE_EL1, 109 }; 110 111 void enable_debug_monitors(enum dbg_active_el el); 112 void disable_debug_monitors(enum dbg_active_el el); 113 114 void user_rewind_single_step(struct task_struct *task); 115 void user_fastforward_single_step(struct task_struct *task); 116 117 void kernel_enable_single_step(struct pt_regs *regs); 118 void kernel_disable_single_step(void); 119 int kernel_active_single_step(void); 120 121 #ifdef CONFIG_HAVE_HW_BREAKPOINT 122 int reinstall_suspended_bps(struct pt_regs *regs); 123 #else 124 static inline int reinstall_suspended_bps(struct pt_regs *regs) 125 { 126 return -ENODEV; 127 } 128 #endif 129 130 int aarch32_break_handler(struct pt_regs *regs); 131 132 #endif /* __ASSEMBLY */ 133 #endif /* __KERNEL__ */ 134 #endif /* __ASM_DEBUG_MONITORS_H */ 135