1 /* Lattice Mico32 exception and system call support.
2 Contributed by Jon Beniston <jon@beniston.com>
4 Copyright (C) 2009-2015 Free Software Foundation, Inc.
6 This file is part of GDB.
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
21 #define WANT_CPU lm32bf
22 #define WANT_CPU_LM32BF
26 #include "targ-vals.h"
28 /* Read memory function for system call interface. */
31 syscall_read_mem (host_callback * cb, struct cb_syscall *sc,
32 unsigned long taddr, char *buf, int bytes)
34 SIM_DESC sd = (SIM_DESC) sc->p1;
35 SIM_CPU *cpu = (SIM_CPU *) sc->p2;
37 return sim_core_read_buffer (sd, cpu, read_map, buf, taddr, bytes);
40 /* Write memory function for system call interface. */
43 syscall_write_mem (host_callback * cb, struct cb_syscall *sc,
44 unsigned long taddr, const char *buf, int bytes)
46 SIM_DESC sd = (SIM_DESC) sc->p1;
47 SIM_CPU *cpu = (SIM_CPU *) sc->p2;
49 return sim_core_write_buffer (sd, cpu, write_map, buf, taddr, bytes);
52 /* Handle invalid instructions. */
55 sim_engine_invalid_insn (SIM_CPU * current_cpu, IADDR cia, SEM_PC pc)
57 SIM_DESC sd = CPU_STATE (current_cpu);
59 sim_engine_halt (sd, current_cpu, NULL, cia, sim_stopped, SIM_SIGILL);
64 /* Handle divide instructions. */
67 lm32bf_divu_insn (SIM_CPU * current_cpu, IADDR pc, USI r0, USI r1, USI r2)
69 SIM_DESC sd = CPU_STATE (current_cpu);
70 host_callback *cb = STATE_CALLBACK (sd);
72 /* Check for divide by zero */
73 if (GET_H_GR (r1) == 0)
75 if (STATE_ENVIRONMENT (sd) != OPERATING_ENVIRONMENT)
76 sim_engine_halt (sd, current_cpu, NULL, pc, sim_stopped, SIM_SIGFPE);
79 /* Save PC in exception address register. */
81 /* Save and clear interrupt enable. */
82 SET_H_CSR (LM32_CSR_IE, (GET_H_CSR (LM32_CSR_IE) & 1) << 1);
83 /* Branch to divide by zero exception handler. */
84 return GET_H_CSR (LM32_CSR_EBA) + LM32_EID_DIVIDE_BY_ZERO * 32;
89 SET_H_GR (r2, (USI) GET_H_GR (r0) / (USI) GET_H_GR (r1));
95 lm32bf_modu_insn (SIM_CPU * current_cpu, IADDR pc, USI r0, USI r1, USI r2)
97 SIM_DESC sd = CPU_STATE (current_cpu);
98 host_callback *cb = STATE_CALLBACK (sd);
100 /* Check for divide by zero. */
101 if (GET_H_GR (r1) == 0)
103 if (STATE_ENVIRONMENT (sd) != OPERATING_ENVIRONMENT)
104 sim_engine_halt (sd, current_cpu, NULL, pc, sim_stopped, SIM_SIGFPE);
107 /* Save PC in exception address register. */
109 /* Save and clear interrupt enable. */
110 SET_H_CSR (LM32_CSR_IE, (GET_H_CSR (LM32_CSR_IE) & 1) << 1);
111 /* Branch to divide by zero exception handler. */
112 return GET_H_CSR (LM32_CSR_EBA) + LM32_EID_DIVIDE_BY_ZERO * 32;
117 SET_H_GR (r2, (USI) GET_H_GR (r0) % (USI) GET_H_GR (r1));
122 /* Handle break instructions. */
125 lm32bf_break_insn (SIM_CPU * current_cpu, IADDR pc)
127 SIM_DESC sd = CPU_STATE (current_cpu);
128 host_callback *cb = STATE_CALLBACK (sd);
130 if (STATE_ENVIRONMENT (sd) != OPERATING_ENVIRONMENT)
132 sim_engine_halt (sd, current_cpu, NULL, pc, sim_stopped, SIM_SIGTRAP);
137 /* Save PC in breakpoint address register. */
139 /* Save and clear interrupt enable. */
140 SET_H_CSR (LM32_CSR_IE, (GET_H_CSR (LM32_CSR_IE) & 1) << 2);
141 /* Branch to breakpoint exception handler. */
142 return GET_H_CSR (LM32_CSR_DEBA) + LM32_EID_BREAKPOINT * 32;
146 /* Handle scall instructions. */
149 lm32bf_scall_insn (SIM_CPU * current_cpu, IADDR pc)
151 SIM_DESC sd = CPU_STATE (current_cpu);
152 host_callback *cb = STATE_CALLBACK (sd);
154 if ((STATE_ENVIRONMENT (sd) != OPERATING_ENVIRONMENT)
155 || (GET_H_GR (8) == TARGET_SYS_exit))
157 /* Delegate system call to host O/S. */
159 CB_SYSCALL_INIT (&s);
161 s.p2 = (PTR) current_cpu;
162 s.read_mem = syscall_read_mem;
163 s.write_mem = syscall_write_mem;
164 /* Extract parameters. */
165 s.func = GET_H_GR (8);
166 s.arg1 = GET_H_GR (1);
167 s.arg2 = GET_H_GR (2);
168 s.arg3 = GET_H_GR (3);
169 /* Halt the simulator if the requested system call is _exit. */
170 if (s.func == TARGET_SYS_exit)
171 sim_engine_halt (sd, current_cpu, NULL, pc, sim_exited, s.arg1);
172 /* Perform the system call. */
174 /* Store the return value in the CPU's registers. */
175 SET_H_GR (1, s.result);
176 SET_H_GR (2, s.result2);
177 SET_H_GR (3, s.errcode);
178 /* Skip over scall instruction. */
183 /* Save PC in exception address register. */
185 /* Save and clear interrupt enable */
186 SET_H_CSR (LM32_CSR_IE, (GET_H_CSR (LM32_CSR_IE) & 1) << 1);
187 /* Branch to system call exception handler. */
188 return GET_H_CSR (LM32_CSR_EBA) + LM32_EID_SYSTEM_CALL * 32;
192 /* Handle b instructions. */
195 lm32bf_b_insn (SIM_CPU * current_cpu, USI r0, USI f_r0)
197 SIM_DESC sd = CPU_STATE (current_cpu);
198 host_callback *cb = STATE_CALLBACK (sd);
200 /* Restore interrupt enable. */
202 SET_H_CSR (LM32_CSR_IE, (GET_H_CSR (LM32_CSR_IE) & 2) >> 1);
204 SET_H_CSR (LM32_CSR_IE, (GET_H_CSR (LM32_CSR_IE) & 4) >> 2);
208 /* Handle wcsr instructions. */
211 lm32bf_wcsr_insn (SIM_CPU * current_cpu, USI f_csr, USI r1)
213 SIM_DESC sd = CPU_STATE (current_cpu);
214 host_callback *cb = STATE_CALLBACK (sd);
216 /* Writing a 1 to IP CSR clears a bit, writing 0 has no effect. */
217 if (f_csr == LM32_CSR_IP)
218 SET_H_CSR (f_csr, GET_H_CSR (f_csr) & ~r1);
220 SET_H_CSR (f_csr, r1);
223 /* Handle signals. */
226 lm32_core_signal (SIM_DESC sd,
232 transfer_type transfer, sim_core_signals sig)
234 const char *copy = (transfer == read_transfer ? "read" : "write");
235 address_word ip = CIA_ADDR (cia);
236 SIM_CPU *current_cpu = cpu;
240 case sim_core_unmapped_signal:
242 "core: %d byte %s to unmapped address 0x%lx at 0x%lx\n",
243 nr_bytes, copy, (unsigned long) addr,
246 /* Save and clear interrupt enable. */
247 SET_H_CSR (LM32_CSR_IE, (GET_H_CSR (LM32_CSR_IE) & 1) << 1);
248 CIA_SET (cpu, GET_H_CSR (LM32_CSR_EBA) + LM32_EID_DATA_BUS_ERROR * 32);
249 sim_engine_halt (sd, cpu, NULL, LM32_EID_DATA_BUS_ERROR * 32,
250 sim_stopped, SIM_SIGSEGV);
252 case sim_core_unaligned_signal:
254 "core: %d byte misaligned %s to address 0x%lx at 0x%lx\n",
255 nr_bytes, copy, (unsigned long) addr,
258 /* Save and clear interrupt enable. */
259 SET_H_CSR (LM32_CSR_IE, (GET_H_CSR (LM32_CSR_IE) & 1) << 1);
260 CIA_SET (cpu, GET_H_CSR (LM32_CSR_EBA) + LM32_EID_DATA_BUS_ERROR * 32);
261 sim_engine_halt (sd, cpu, NULL, LM32_EID_DATA_BUS_ERROR * 32,
262 sim_stopped, SIM_SIGBUS);
265 sim_engine_abort (sd, cpu, cia,
266 "sim_core_signal - internal error - bad switch");