1 /* 2 * RISC-V GDB Server Stub 3 * 4 * Copyright (c) 2016-2017 Sagar Karandikar, sagark@eecs.berkeley.edu 5 * 6 * This program is free software; you can redistribute it and/or modify it 7 * under the terms and conditions of the GNU General Public License, 8 * version 2 or later, as published by the Free Software Foundation. 9 * 10 * This program is distributed in the hope it will be useful, but WITHOUT 11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 13 * more details. 14 * 15 * You should have received a copy of the GNU General Public License along with 16 * this program. If not, see <http://www.gnu.org/licenses/>. 17 */ 18 19 #include "qemu/osdep.h" 20 #include "qemu-common.h" 21 #include "exec/gdbstub.h" 22 #include "cpu.h" 23 24 int riscv_cpu_gdb_read_register(CPUState *cs, uint8_t *mem_buf, int n) 25 { 26 RISCVCPU *cpu = RISCV_CPU(cs); 27 CPURISCVState *env = &cpu->env; 28 29 if (n < 32) { 30 return gdb_get_regl(mem_buf, env->gpr[n]); 31 } else if (n == 32) { 32 return gdb_get_regl(mem_buf, env->pc); 33 } else if (n < 65) { 34 return gdb_get_reg64(mem_buf, env->fpr[n - 33]); 35 } else if (n < 4096 + 65) { 36 target_ulong val = 0; 37 if (riscv_csrrw(env, n - 65, &val, 0, 0) == 0) { 38 return gdb_get_regl(mem_buf, val); 39 } 40 } 41 return 0; 42 } 43 44 int riscv_cpu_gdb_write_register(CPUState *cs, uint8_t *mem_buf, int n) 45 { 46 RISCVCPU *cpu = RISCV_CPU(cs); 47 CPURISCVState *env = &cpu->env; 48 49 if (n == 0) { 50 /* discard writes to x0 */ 51 return sizeof(target_ulong); 52 } else if (n < 32) { 53 env->gpr[n] = ldtul_p(mem_buf); 54 return sizeof(target_ulong); 55 } else if (n == 32) { 56 env->pc = ldtul_p(mem_buf); 57 return sizeof(target_ulong); 58 } else if (n < 65) { 59 env->fpr[n - 33] = ldq_p(mem_buf); /* always 64-bit */ 60 return sizeof(uint64_t); 61 } else if (n < 4096 + 65) { 62 target_ulong val = ldtul_p(mem_buf); 63 if (riscv_csrrw(env, n - 65, NULL, val, -1) == 0) { 64 return sizeof(target_ulong); 65 } 66 } 67 return 0; 68 } 69