| 1 | /* |
| 2 | * QEMU AVR gdbstub |
| 3 | * |
| 4 | * Copyright (c) 2016-2020 Michael Rolnik |
| 5 | * |
| 6 | * This library is free software; you can redistribute it and/or |
| 7 | * modify it under the terms of the GNU Lesser General Public |
| 8 | * License as published by the Free Software Foundation; either |
| 9 | * version 2.1 of the License, or (at your option) any later version. |
| 10 | * |
| 11 | * This library is distributed in the hope that it will be useful, |
| 12 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 14 | * Lesser General Public License for more details. |
| 15 | * |
| 16 | * You should have received a copy of the GNU Lesser General Public |
| 17 | * License along with this library; if not, see |
| 18 | * <http://www.gnu.org/licenses/lgpl-2.1.html> |
| 19 | */ |
| 20 | |
| 21 | #include "qemu/osdep.h" |
| 22 | #include "gdbstub/helpers.h" |
| 23 | #include "cpu.h" |
| 24 | |
| 25 | int avr_cpu_gdb_read_register(CPUState *cs, GByteArray *mem_buf, int n) |
| 26 | { |
| 27 | CPUAVRState *env = cpu_env(cs); |
| 28 | |
| 29 | /* R */ |
| 30 | if (n < 32) { |
| 31 | return gdb_get_reg8(mem_buf, env->r[n]); |
| 32 | } |
| 33 | |
| 34 | /* SREG */ |
| 35 | if (n == 32) { |
| 36 | uint8_t sreg = cpu_get_sreg(env); |
| 37 | |
| 38 | return gdb_get_reg8(mem_buf, sreg); |
| 39 | } |
| 40 | |
| 41 | /* SP */ |
| 42 | if (n == 33) { |
| 43 | return gdb_get_reg16(mem_buf, env->sp & 0x0000ffff); |
| 44 | } |
| 45 | |
| 46 | /* PC */ |
| 47 | if (n == 34) { |
| 48 | return gdb_get_reg32(mem_buf, env->pc_w * 2); |
| 49 | } |
| 50 | |
| 51 | return 0; |
| 52 | } |
| 53 | |
| 54 | int avr_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n) |
| 55 | { |
| 56 | CPUAVRState *env = cpu_env(cs); |
| 57 | |
| 58 | /* R */ |
| 59 | if (n < 32) { |
| 60 | env->r[n] = *mem_buf; |
| 61 | return 1; |
| 62 | } |
| 63 | |
| 64 | /* SREG */ |
| 65 | if (n == 32) { |
| 66 | cpu_set_sreg(env, *mem_buf); |
| 67 | return 1; |
| 68 | } |
| 69 | |
| 70 | /* SP */ |
| 71 | if (n == 33) { |
| 72 | env->sp = lduw_le_p(mem_buf); |
| 73 | return 2; |
| 74 | } |
| 75 | |
| 76 | /* PC */ |
| 77 | if (n == 34) { |
| 78 | env->pc_w = ldl_le_p(mem_buf) / 2; |
| 79 | return 4; |
| 80 | } |
| 81 | |
| 82 | return 0; |
| 83 | } |
| 84 | |
| 85 | vaddr avr_cpu_gdb_adjust_breakpoint(CPUState *cpu, vaddr addr) |
| 86 | { |
| 87 | /* |
| 88 | * This is due to some strange GDB behavior |
| 89 | * Let's assume main has address 0x100: |
| 90 | * b main - sets breakpoint at address 0x00000100 (code) |
| 91 | * b *0x100 - sets breakpoint at address 0x00800100 (data) |
| 92 | * |
| 93 | * Force all breakpoints into code space. |
| 94 | */ |
| 95 | return addr % OFFSET_DATA; |
| 96 | } |