1 /*- 2 * Copyright (c) 2015 The FreeBSD Foundation 3 * All rights reserved. 4 * 5 * This software was developed by Semihalf under 6 * the sponsorship of the FreeBSD Foundation. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 27 * SUCH DAMAGE. 28 */ 29 30 #include <sys/cdefs.h> 31 __FBSDID("$FreeBSD$"); 32 #include <sys/param.h> 33 #include <sys/proc.h> 34 #include <sys/kdb.h> 35 #include <machine/pcb.h> 36 #include <ddb/ddb.h> 37 #include <ddb/db_sym.h> 38 39 #include <machine/armreg.h> 40 #include <machine/debug_monitor.h> 41 42 struct unwind_state { 43 uint64_t fp; 44 uint64_t sp; 45 uint64_t pc; 46 }; 47 48 void 49 db_md_list_watchpoints() 50 { 51 52 dbg_show_watchpoint(); 53 } 54 55 int 56 db_md_clr_watchpoint(db_expr_t addr, db_expr_t size) 57 { 58 59 return (dbg_remove_watchpoint(addr, size, DBG_FROM_EL1)); 60 } 61 62 int 63 db_md_set_watchpoint(db_expr_t addr, db_expr_t size) 64 { 65 66 return (dbg_setup_watchpoint(addr, size, DBG_FROM_EL1, 67 HW_BREAKPOINT_RW)); 68 } 69 70 static int 71 db_unwind_frame(struct unwind_state *frame) 72 { 73 uint64_t fp = frame->fp; 74 75 if (fp == 0) 76 return -1; 77 78 frame->sp = fp + 0x10; 79 /* FP to previous frame (X29) */ 80 frame->fp = *(uint64_t *)(fp); 81 /* LR (X30) */ 82 frame->pc = *(uint64_t *)(fp + 8) - 4; 83 return (0); 84 } 85 86 static void 87 db_stack_trace_cmd(struct unwind_state *frame) 88 { 89 c_db_sym_t sym; 90 const char *name; 91 db_expr_t value; 92 db_expr_t offset; 93 94 while (1) { 95 uint64_t pc = frame->pc; 96 int ret; 97 98 ret = db_unwind_frame(frame); 99 if (ret < 0) 100 break; 101 102 sym = db_search_symbol(pc, DB_STGY_ANY, &offset); 103 if (sym == C_DB_SYM_NULL) { 104 value = 0; 105 name = "(null)"; 106 } else 107 db_symbol_values(sym, &name, &value); 108 109 db_printf("%s() at ", name); 110 db_printsym(frame->pc, DB_STGY_PROC); 111 db_printf("\n"); 112 113 db_printf("\t pc = 0x%016lx lr = 0x%016lx\n", pc, 114 frame->pc); 115 db_printf("\t sp = 0x%016lx fp = 0x%016lx\n", frame->sp, 116 frame->fp); 117 /* TODO: Show some more registers */ 118 db_printf("\n"); 119 } 120 } 121 122 int 123 db_trace_thread(struct thread *thr, int count) 124 { 125 struct unwind_state frame; 126 struct pcb *ctx; 127 128 if (thr != curthread) { 129 ctx = kdb_thr_ctx(thr); 130 131 frame.sp = (uint64_t)ctx->pcb_sp; 132 frame.fp = (uint64_t)ctx->pcb_x[29]; 133 frame.pc = (uint64_t)ctx->pcb_x[30]; 134 db_stack_trace_cmd(&frame); 135 } else 136 db_trace_self(); 137 return (0); 138 } 139 140 void 141 db_trace_self(void) 142 { 143 struct unwind_state frame; 144 uint64_t sp; 145 146 __asm __volatile("mov %0, sp" : "=&r" (sp)); 147 148 frame.sp = sp; 149 frame.fp = (uint64_t)__builtin_frame_address(0); 150 frame.pc = (uint64_t)db_trace_self; 151 db_stack_trace_cmd(&frame); 152 } 153