xref: /netbsd-src/external/gpl3/gdb/dist/sim/or1k/or1k.c (revision 0388e998654430ce19a2917dec7ff0950bcf2e1c)
1 /* OpenRISC simulator support code
2    Copyright (C) 2017-2024 Free Software Foundation, Inc.
3 
4    This file is part of GDB, the GNU debugger.
5 
6    This program is free software; you can redistribute it and/or modify
7    it under the terms of the GNU General Public License as published by
8    the Free Software Foundation; either version 3 of the License, or
9    (at your option) any later version.
10 
11    This program 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
14    GNU General Public License for more details.
15 
16    You should have received a copy of the GNU General Public License
17    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
18 
19 /* This must come before any other includes.  */
20 #include "defs.h"
21 
22 #define WANT_CPU_OR1K32BF
23 #define WANT_CPU
24 
25 #include "sim-main.h"
26 #include "symcat.h"
27 #include "cgen-ops.h"
28 #include "cgen-mem.h"
29 #include "cpuall.h"
30 
31 #include <string.h>
32 
33 int
34 or1k32bf_fetch_register (sim_cpu *current_cpu, int rn, void *buf, int len)
35 {
36   if (rn < 32)
37     SETTWI (buf, GET_H_GPR (rn));
38   else
39     switch (rn)
40       {
41       case PPC_REGNUM:
42 	SETTWI (buf, GET_H_SYS_PPC ());
43 	break;
44       case PC_REGNUM:
45 	SETTWI (buf, GET_H_PC ());
46 	break;
47       case SR_REGNUM:
48 	SETTWI (buf, GET_H_SYS_SR ());
49 	break;
50       default:
51 	return 0;
52       }
53   return sizeof (WI);		/* WI from arch.h */
54 }
55 
56 int
57 or1k32bf_store_register (sim_cpu *current_cpu, int rn, const void *buf, int len)
58 {
59   if (rn < 32)
60     SET_H_GPR (rn, GETTWI (buf));
61   else
62     switch (rn)
63       {
64       case PPC_REGNUM:
65 	SET_H_SYS_PPC (GETTWI (buf));
66 	break;
67       case PC_REGNUM:
68 	SET_H_PC (GETTWI (buf));
69 	break;
70       case SR_REGNUM:
71 	SET_H_SYS_SR (GETTWI (buf));
72 	break;
73       default:
74 	return 0;
75       }
76   return sizeof (WI);		/* WI from arch.h */
77 }
78 
79 int
80 or1k32bf_model_or1200_u_exec (sim_cpu *current_cpu, const IDESC *idesc,
81 			      int unit_num, int referenced)
82 {
83   return -1;
84 }
85 
86 int
87 or1k32bf_model_or1200nd_u_exec (sim_cpu *current_cpu, const IDESC *idesc,
88 				int unit_num, int referenced)
89 {
90   return -1;
91 }
92 
93 void
94 or1k32bf_model_insn_before (sim_cpu *current_cpu, int first_p)
95 {
96 }
97 
98 void
99 or1k32bf_model_insn_after (sim_cpu *current_cpu, int last_p, int cycles)
100 {
101 }
102 
103 USI
104 or1k32bf_h_spr_get_raw (sim_cpu *current_cpu, USI addr)
105 {
106   SIM_DESC sd = CPU_STATE (current_cpu);
107   struct or1k_sim_cpu *or1k_cpu = OR1K_SIM_CPU (current_cpu);
108 
109   SIM_ASSERT (addr < NUM_SPR);
110   return or1k_cpu->spr[addr];
111 }
112 
113 void
114 or1k32bf_h_spr_set_raw (sim_cpu *current_cpu, USI addr, USI val)
115 {
116   SIM_DESC sd = CPU_STATE (current_cpu);
117   struct or1k_sim_cpu *or1k_cpu = OR1K_SIM_CPU (current_cpu);
118 
119   SIM_ASSERT (addr < NUM_SPR);
120   or1k_cpu->spr[addr] = val;
121 }
122 
123 USI
124 or1k32bf_h_spr_field_get_raw (sim_cpu *current_cpu, USI addr, int msb, int lsb)
125 {
126   SIM_DESC sd = CPU_STATE (current_cpu);
127   struct or1k_sim_cpu *or1k_cpu = OR1K_SIM_CPU (current_cpu);
128 
129   SIM_ASSERT (addr < NUM_SPR);
130   return LSEXTRACTED (or1k_cpu->spr[addr], msb, lsb);
131 }
132 
133 void
134 or1k32bf_h_spr_field_set_raw (sim_cpu *current_cpu, USI addr, int msb, int lsb,
135 			      USI val)
136 {
137   struct or1k_sim_cpu *or1k_cpu = OR1K_SIM_CPU (current_cpu);
138 
139   or1k_cpu->spr[addr] &= ~LSMASK32 (msb, lsb);
140   or1k_cpu->spr[addr] |= LSINSERTED (val, msb, lsb);
141 }
142 
143 /* Initialize a sim cpu object.  */
144 void
145 or1k_cpu_init (SIM_DESC sd, sim_cpu *current_cpu, const USI or1k_vr,
146 	       const USI or1k_upr, const USI or1k_cpucfgr)
147 {
148   struct or1k_sim_cpu *or1k_cpu = OR1K_SIM_CPU (current_cpu);
149 
150   /* Set the configuration registers passed from the user.  */
151   SET_H_SYS_VR (or1k_vr);
152   SET_H_SYS_UPR (or1k_upr);
153   SET_H_SYS_CPUCFGR (or1k_cpucfgr);
154 
155 #define CHECK_SPR_FIELD(GROUP, INDEX, FIELD, test) \
156   do \
157     { \
158       USI field = GET_H_##SYS##_##INDEX##_##FIELD (); \
159       if (!(test)) \
160 	sim_io_eprintf \
161 	  (sd, "WARNING: unsupported %s field in %s register: 0x%x\n", \
162 	   #FIELD, #INDEX, field); \
163     } while (0)
164 
165   /* Set flags indicating if we are in a delay slot or not.  */
166   or1k_cpu->next_delay_slot = 0;
167   or1k_cpu->delay_slot = 0;
168 
169   /* Verify any user passed fields and warn on configurations we don't
170      support.  */
171   CHECK_SPR_FIELD (SYS, UPR, UP, field == 1);
172   CHECK_SPR_FIELD (SYS, UPR, DCP, field == 0);
173   CHECK_SPR_FIELD (SYS, UPR, ICP, field == 0);
174   CHECK_SPR_FIELD (SYS, UPR, DMP, field == 0);
175   CHECK_SPR_FIELD (SYS, UPR, MP, field == 0);
176   CHECK_SPR_FIELD (SYS, UPR, IMP, field == 0);
177   CHECK_SPR_FIELD (SYS, UPR, DUP, field == 0);
178   CHECK_SPR_FIELD (SYS, UPR, PCUP, field == 0);
179   CHECK_SPR_FIELD (SYS, UPR, PICP, field == 0);
180   CHECK_SPR_FIELD (SYS, UPR, PMP, field == 0);
181   CHECK_SPR_FIELD (SYS, UPR, TTP, field == 0);
182   CHECK_SPR_FIELD (SYS, UPR, CUP, field == 0);
183 
184   CHECK_SPR_FIELD (SYS, CPUCFGR, NSGR, field == 0);
185   CHECK_SPR_FIELD (SYS, CPUCFGR, CGF, field == 0);
186   CHECK_SPR_FIELD (SYS, CPUCFGR, OB32S, field == 1);
187   CHECK_SPR_FIELD (SYS, CPUCFGR, OF32S, field == 1);
188   CHECK_SPR_FIELD (SYS, CPUCFGR, OB64S, field == 0);
189   CHECK_SPR_FIELD (SYS, CPUCFGR, OF64S, field == 0);
190   CHECK_SPR_FIELD (SYS, CPUCFGR, OV64S, field == 0);
191 
192 #undef CHECK_SPR_FIELD
193 
194   /* Configure the fpu operations and mark fpu available.  */
195   cgen_init_accurate_fpu (current_cpu, CGEN_CPU_FPU (current_cpu),
196 			  or1k32bf_fpu_error);
197   SET_H_SYS_CPUCFGR_OF32S (1);
198 
199   /* Set the UPR[UP] flag, even if the user tried to unset it, as we always
200      support the Unit Present Register.  */
201   SET_H_SYS_UPR_UP (1);
202 
203   /* Set the supervisor register to indicate we are in supervisor mode and
204      set the Fixed-One bit which must always be set.  */
205   SET_H_SYS_SR (SPR_FIELD_MASK_SYS_SR_SM | SPR_FIELD_MASK_SYS_SR_FO);
206 
207   /* Clear the floating point control status register.  */
208   SET_H_SYS_FPCSR (0);
209 }
210 
211 void
212 or1k32bf_insn_before (sim_cpu *current_cpu, SEM_PC vpc, const IDESC *idesc)
213 {
214   SIM_DESC sd = CPU_STATE (current_cpu);
215   struct or1k_sim_cpu *or1k_cpu = OR1K_SIM_CPU (current_cpu);
216 
217   or1k_cpu->delay_slot = or1k_cpu->next_delay_slot;
218   or1k_cpu->next_delay_slot = 0;
219 
220   if (or1k_cpu->delay_slot &&
221       CGEN_ATTR_BOOLS (CGEN_INSN_ATTRS ((idesc)->idata)) &
222       CGEN_ATTR_MASK (CGEN_INSN_NOT_IN_DELAY_SLOT))
223     {
224       USI pc;
225 #ifdef WITH_SCACHE
226       pc = vpc->argbuf.addr;
227 #else
228       pc = vpc;
229 #endif
230       sim_io_error (sd, "invalid instruction in a delay slot at PC 0x%08x",
231 		    pc);
232     }
233 
234 }
235 
236 void
237 or1k32bf_insn_after (sim_cpu *current_cpu, SEM_PC vpc, const IDESC *idesc)
238 {
239   SIM_DESC sd = CPU_STATE (current_cpu);
240   struct or1k_sim_cpu *or1k_cpu = OR1K_SIM_CPU (current_cpu);
241   USI ppc;
242 
243 #ifdef WITH_SCACHE
244   ppc = vpc->argbuf.addr;
245 #else
246   ppc = vpc;
247 #endif
248 
249   SET_H_SYS_PPC (ppc);
250 
251   if (!GET_H_SYS_CPUCFGR_ND () &&
252       CGEN_ATTR_BOOLS (CGEN_INSN_ATTRS ((idesc)->idata)) &
253       CGEN_ATTR_MASK (CGEN_INSN_DELAYED_CTI))
254     {
255       SIM_ASSERT (!or1k_cpu->delay_slot);
256       or1k_cpu->next_delay_slot = 1;
257     }
258 }
259 
260 void
261 or1k32bf_nop (sim_cpu *current_cpu, USI uimm16)
262 {
263   SIM_DESC sd = CPU_STATE (current_cpu);
264 
265   switch (uimm16)
266     {
267 
268     case NOP_NOP:
269       break;
270 
271     case NOP_EXIT:
272       sim_io_printf (CPU_STATE (current_cpu), "exit(%d)\n", GET_H_GPR (3));
273       ATTRIBUTE_FALLTHROUGH;
274     case NOP_EXIT_SILENT:
275       sim_engine_halt (sd, current_cpu, NULL, CPU_PC_GET (current_cpu),
276 		       sim_exited, GET_H_GPR (3));
277       break;
278 
279     case NOP_REPORT:
280       sim_io_printf (CPU_STATE (current_cpu), "report(0x%08x);\n",
281 		     GET_H_GPR (3));
282       break;
283 
284     case NOP_PUTC:
285       sim_io_printf (CPU_STATE (current_cpu), "%c",
286 		     (char) (GET_H_GPR (3) & 0xff));
287       break;
288 
289     default:
290       sim_io_eprintf (sd, "WARNING: l.nop with unsupported code 0x%08x\n",
291 		      uimm16);
292       break;
293     }
294 
295 }
296 
297 /* Build an address value used for load and store instructions.  For example,
298    the instruction 'l.lws rD, I(rA)' will require to load data from the 4 byte
299    address represented by rA + I.  Here the argument base is rA, offset is I
300    and the size is the read size in bytes.  Note, OpenRISC requires that word
301    and half-word access be word and half-word aligned respectively, the check
302    for alignment is not needed here.  */
303 
304 USI
305 or1k32bf_make_load_store_addr (sim_cpu *current_cpu, USI base, SI offset,
306 			       int size)
307 {
308   SIM_DESC sd = CPU_STATE (current_cpu);
309 
310   USI addr = base + offset;
311 
312   /* If little endian load/store is enabled we adjust the byte and half-word
313      addresses to the little endian equivalent.  */
314   if (GET_H_SYS_SR_LEE ())
315     {
316       switch (size)
317 	{
318 
319 	case 4: /* We are retrieving the entire word no adjustment.  */
320 	  break;
321 
322 	case 2: /* Perform half-word adjustment 0 -> 2, 2 -> 0.  */
323 	  addr ^= 0x2;
324 	  break;
325 
326 	case 1: /* Perform byte adjustment, 0 -> 3, 2 -> 3, etc.  */
327 	  addr ^= 0x3;
328 	  break;
329 
330 	default:
331 	  SIM_ASSERT (0);
332 	  return 0;
333 	}
334     }
335 
336   return addr;
337 }
338 
339 /* The find first 1 instruction returns the location of the first set bit
340    in the argument register.  */
341 
342 USI
343 or1k32bf_ff1 (sim_cpu *current_cpu, USI val)
344 {
345   USI bit;
346   USI ret;
347   for (bit = 1, ret = 1; bit; bit <<= 1, ret++)
348     {
349       if (val & bit)
350 	return ret;
351     }
352   return 0;
353 }
354 
355 /* The find last 1 instruction returns the location of the last set bit in
356    the argument register.  */
357 
358 USI
359 or1k32bf_fl1 (sim_cpu *current_cpu, USI val)
360 {
361   USI bit;
362   USI ret;
363   for (bit = 1 << 31, ret = 32; bit; bit >>= 1, ret--)
364     {
365       if (val & bit)
366 	return ret;
367     }
368   return 0;
369 }
370