/* * \brief Fiasco.OC(ARM)-specific helper functions for GDB server * \author Christian Prochaska * \date 2011-08-01 */ /* * Copyright (C) 2011-2017 Genode Labs GmbH * * This file is part of the Genode OS framework, which is distributed * under the terms of the GNU Affero General Public License version 3. */ /* Genode includes */ #include /* GDB monitor includes */ #include "cpu_session_component.h" #include "reg-arm.h" #include "gdbserver_platform_helper.h" #include "genode_child_resources.h" extern "C" { #define private _private #include "genode-low.h" #define _private private } using namespace Genode; static bool in_syscall(Thread_state const &ts) { try { /* looking for syscall pattern: * (PC-8: e1a0e00f mov lr, pc) * PC-4: e3e0f00b mvn pc, #11 * (PC: e1a02004 mov r2, r4) */ if ((genode_read_memory_byte((void*)(ts.ip - 1)) == 0xe3) && (genode_read_memory_byte((void*)(ts.ip - 2)) == 0xe0) && (genode_read_memory_byte((void*)(ts.ip - 3)) == 0xf0) && (genode_read_memory_byte((void*)(ts.ip - 4)) == 0x0b)) return true; } catch (No_memory_at_address) { return false; } return false; } extern "C" int genode_fetch_register(int regno, unsigned long *value) { Thread_state ts; try { ts = get_current_thread_state(); } catch (...) { error(__PRETTY_FUNCTION__, ": could not get current thread state"); return -1; } if (in_syscall(ts) || ts.unresolved_page_fault) { switch((enum reg_index)regno) { case R0: cannot_fetch_register("R0"); return -1; case R1: cannot_fetch_register("R1"); return -1; case R2: cannot_fetch_register("R2"); return -1; case R3: cannot_fetch_register("R3"); return -1; case R4: cannot_fetch_register("R4"); return -1; case R5: cannot_fetch_register("R5"); return -1; case R6: cannot_fetch_register("R6"); return -1; case R7: cannot_fetch_register("R7"); return -1; case R8: cannot_fetch_register("R8"); return -1; case R9: cannot_fetch_register("R9"); return -1; case R10: cannot_fetch_register("R10"); return -1; case R11: if (in_syscall(ts)) { /* R11 can be calculated from SP. The offset can be found in * the disassembled 'Fiasco::l4_ipc()' function: * add r11, sp, #8 -> r11 = sp + 8 * sub sp, sp, #20 -> r11 = (sp + 20) + 8 */ *value = (ts.sp + 20) + 8; /* for the debug output, if enabled */ fetch_register("R11", *value, *value); return 0; } else { cannot_fetch_register("R11"); return -1; } case R12: cannot_fetch_register("R12"); return -1; case SP: fetch_register("SP ", ts.sp, *value); return 0; case LR: cannot_fetch_register("LR"); return -1; case PC: fetch_register("PC ", ts.ip, *value); return 0; case F0: cannot_fetch_register("F0"); return -1; case F1: cannot_fetch_register("F1"); return -1; case F2: cannot_fetch_register("F2"); return -1; case F3: cannot_fetch_register("F3"); return -1; case F4: cannot_fetch_register("F4"); return -1; case F5: cannot_fetch_register("F5"); return -1; case F6: cannot_fetch_register("F6"); return -1; case F7: cannot_fetch_register("F7"); return -1; case FPS: cannot_fetch_register("FPS"); return -1; case CPSR: cannot_fetch_register("CPSR"); return -1; default: error("unhandled register ", regno); return -1; } } else { switch((enum reg_index)regno) { case R0: fetch_register("R0 ", ts.r0, *value); return 0; case R1: fetch_register("R1 ", ts.r1, *value); return 0; case R2: fetch_register("R2 ", ts.r2, *value); return 0; case R3: fetch_register("R3 ", ts.r3, *value); return 0; case R4: fetch_register("R4 ", ts.r4, *value); return 0; case R5: fetch_register("R5 ", ts.r5, *value); return 0; case R6: fetch_register("R6 ", ts.r6, *value); return 0; case R7: fetch_register("R7 ", ts.r7, *value); return 0; case R8: fetch_register("R8 ", ts.r8, *value); return 0; case R9: fetch_register("R9 ", ts.r9, *value); return 0; case R10: fetch_register("R10 ", ts.r10, *value); return 0; case R11: fetch_register("R11 ", ts.r11, *value); return 0; case R12: fetch_register("R12 ", ts.r12, *value); return 0; case SP: fetch_register("SP ", ts.sp, *value); return 0; case LR: fetch_register("LR ", ts.lr, *value); return 0; case PC: fetch_register("PC ", ts.ip, *value); return 0; case F0: cannot_fetch_register("F0"); return -1; case F1: cannot_fetch_register("F1"); return -1; case F2: cannot_fetch_register("F2"); return -1; case F3: cannot_fetch_register("F3"); return -1; case F4: cannot_fetch_register("F4"); return -1; case F5: cannot_fetch_register("F5"); return -1; case F6: cannot_fetch_register("F6"); return -1; case F7: cannot_fetch_register("F7"); return -1; case FPS: cannot_fetch_register("FPS"); return -1; case CPSR: fetch_register("CPSR", ts.cpsr, *value); return 0; default: error("unhandled register ", regno); return -1; } } return -1; } extern "C" void genode_store_register(int regno, unsigned long value) { Thread_state ts; try { ts = get_current_thread_state(); } catch (...) { error(__PRETTY_FUNCTION__, ": could not get current thread state"); return; } if (in_syscall(ts)) { log("cannot set registers while thread is in syscall"); return; } switch((enum reg_index)regno) { case R0: if (!store_register("R0 ", ts.r0, value)) return; break; case R1: if (!store_register("R1 ", ts.r1, value)) return; break; case R2: if (!store_register("R2 ", ts.r2, value)) return; break; case R3: if (!store_register("R3 ", ts.r3, value)) return; break; case R4: if (!store_register("R4 ", ts.r4, value)) return; break; case R5: if (!store_register("R5 ", ts.r5, value)) return; break; case R6: if (!store_register("R6 ", ts.r6, value)) return; break; case R7: if (!store_register("R7 ", ts.r7, value)) return; break; case R8: if (!store_register("R8 ", ts.r8, value)) return; break; case R9: if (!store_register("R9 ", ts.r9, value)) return; break; case R10: if (!store_register("R10 ", ts.r10, value)) return; break; case R11: if (!store_register("R11 ", ts.r11, value)) return; break; case R12: if (!store_register("R12 ", ts.r12, value)) return; break; case SP: if (!store_register("SP ", ts.sp, value)) return; break; case LR: if (!store_register("LR ", ts.lr, value)) return; break; case PC: if (!store_register("PC ", ts.ip, value)) return; break; case F0: cannot_store_register("F0 ", value); return; case F1: cannot_store_register("F1 ", value); return; case F2: cannot_store_register("F2 ", value); return; case F3: cannot_store_register("F3 ", value); return; case F4: cannot_store_register("F4 ", value); return; case F5: cannot_store_register("F5 ", value); return; case F6: cannot_store_register("F6 ", value); return; case F7: cannot_store_register("F7 ", value); return; case FPS: cannot_store_register("FPS", value); return; case CPSR: if (!store_register("CPSR", ts.cpsr, value)) return; break; } set_current_thread_state(ts); }