xref: /openbmc/qemu/target/xtensa/helper.c (revision dd8d6a2d)
1 /*
2  * Copyright (c) 2011, Max Filippov, Open Source and Linux Lab.
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions are met:
7  *     * Redistributions of source code must retain the above copyright
8  *       notice, this list of conditions and the following disclaimer.
9  *     * Redistributions in binary form must reproduce the above copyright
10  *       notice, this list of conditions and the following disclaimer in the
11  *       documentation and/or other materials provided with the distribution.
12  *     * Neither the name of the Open Source and Linux Lab nor the
13  *       names of its contributors may be used to endorse or promote products
14  *       derived from this software without specific prior written permission.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
17  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
20  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
21  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
22  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
23  * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
25  * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include "qemu/osdep.h"
29 #include "cpu.h"
30 #include "exec/exec-all.h"
31 #include "exec/gdbstub.h"
32 #include "exec/helper-proto.h"
33 #include "qemu/error-report.h"
34 #include "qemu/host-utils.h"
35 
36 static struct XtensaConfigList *xtensa_cores;
37 
38 static void add_translator_to_hash(GHashTable *translator,
39                                    const char *name,
40                                    const XtensaOpcodeOps *opcode)
41 {
42     if (!g_hash_table_insert(translator, (void *)name, (void *)opcode)) {
43         error_report("Multiple definitions of '%s' opcode in a single table",
44                      name);
45     }
46 }
47 
48 static GHashTable *hash_opcode_translators(const XtensaOpcodeTranslators *t)
49 {
50     unsigned i, j;
51     GHashTable *translator = g_hash_table_new(g_str_hash, g_str_equal);
52 
53     for (i = 0; i < t->num_opcodes; ++i) {
54         if (t->opcode[i].op_flags & XTENSA_OP_NAME_ARRAY) {
55             const char * const *name = t->opcode[i].name;
56 
57             for (j = 0; name[j]; ++j) {
58                 add_translator_to_hash(translator,
59                                        (void *)name[j],
60                                        (void *)(t->opcode + i));
61             }
62         } else {
63             add_translator_to_hash(translator,
64                                    (void *)t->opcode[i].name,
65                                    (void *)(t->opcode + i));
66         }
67     }
68     return translator;
69 }
70 
71 static XtensaOpcodeOps *
72 xtensa_find_opcode_ops(const XtensaOpcodeTranslators *t,
73                        const char *name)
74 {
75     static GHashTable *translators;
76     GHashTable *translator;
77 
78     if (translators == NULL) {
79         translators = g_hash_table_new(g_direct_hash, g_direct_equal);
80     }
81     translator = g_hash_table_lookup(translators, t);
82     if (translator == NULL) {
83         translator = hash_opcode_translators(t);
84         g_hash_table_insert(translators, (void *)t, translator);
85     }
86     return g_hash_table_lookup(translator, name);
87 }
88 
89 static void init_libisa(XtensaConfig *config)
90 {
91     unsigned i, j;
92     unsigned opcodes;
93     unsigned formats;
94     unsigned regfiles;
95 
96     config->isa = xtensa_isa_init(config->isa_internal, NULL, NULL);
97     assert(xtensa_isa_maxlength(config->isa) <= MAX_INSN_LENGTH);
98     opcodes = xtensa_isa_num_opcodes(config->isa);
99     formats = xtensa_isa_num_formats(config->isa);
100     regfiles = xtensa_isa_num_regfiles(config->isa);
101     config->opcode_ops = g_new(XtensaOpcodeOps *, opcodes);
102 
103     for (i = 0; i < formats; ++i) {
104         assert(xtensa_format_num_slots(config->isa, i) <= MAX_INSN_SLOTS);
105     }
106 
107     for (i = 0; i < opcodes; ++i) {
108         const char *opc_name = xtensa_opcode_name(config->isa, i);
109         XtensaOpcodeOps *ops = NULL;
110 
111         assert(xtensa_opcode_num_operands(config->isa, i) <= MAX_OPCODE_ARGS);
112         if (!config->opcode_translators) {
113             ops = xtensa_find_opcode_ops(&xtensa_core_opcodes, opc_name);
114         } else {
115             for (j = 0; !ops && config->opcode_translators[j]; ++j) {
116                 ops = xtensa_find_opcode_ops(config->opcode_translators[j],
117                                              opc_name);
118             }
119         }
120 #ifdef DEBUG
121         if (ops == NULL) {
122             fprintf(stderr,
123                     "opcode translator not found for %s's opcode '%s'\n",
124                     config->name, opc_name);
125         }
126 #endif
127         config->opcode_ops[i] = ops;
128     }
129     config->a_regfile = xtensa_regfile_lookup(config->isa, "AR");
130 
131     config->regfile = g_new(void **, regfiles);
132     for (i = 0; i < regfiles; ++i) {
133         const char *name = xtensa_regfile_name(config->isa, i);
134 
135         config->regfile[i] = xtensa_get_regfile_by_name(name);
136 #ifdef DEBUG
137         if (config->regfile[i] == NULL) {
138             fprintf(stderr, "regfile '%s' not found for %s\n",
139                     name, config->name);
140         }
141 #endif
142     }
143 }
144 
145 static void xtensa_finalize_config(XtensaConfig *config)
146 {
147     if (config->isa_internal) {
148         init_libisa(config);
149     }
150 
151     if (config->gdb_regmap.num_regs == 0 ||
152         config->gdb_regmap.num_core_regs == 0) {
153         unsigned n_regs = 0;
154         unsigned n_core_regs = 0;
155 
156         xtensa_count_regs(config, &n_regs, &n_core_regs);
157         if (config->gdb_regmap.num_regs == 0) {
158             config->gdb_regmap.num_regs = n_regs;
159         }
160         if (config->gdb_regmap.num_core_regs == 0) {
161             config->gdb_regmap.num_core_regs = n_core_regs;
162         }
163     }
164 }
165 
166 static void xtensa_core_class_init(ObjectClass *oc, void *data)
167 {
168     CPUClass *cc = CPU_CLASS(oc);
169     XtensaCPUClass *xcc = XTENSA_CPU_CLASS(oc);
170     XtensaConfig *config = data;
171 
172     xtensa_finalize_config(config);
173     xcc->config = config;
174 
175     /*
176      * Use num_core_regs to see only non-privileged registers in an unmodified
177      * gdb. Use num_regs to see all registers. gdb modification is required
178      * for that: reset bit 0 in the 'flags' field of the registers definitions
179      * in the gdb/xtensa-config.c inside gdb source tree or inside gdb overlay.
180      */
181     cc->gdb_num_core_regs = config->gdb_regmap.num_regs;
182 }
183 
184 void xtensa_register_core(XtensaConfigList *node)
185 {
186     TypeInfo type = {
187         .parent = TYPE_XTENSA_CPU,
188         .class_init = xtensa_core_class_init,
189         .class_data = (void *)node->config,
190     };
191 
192     node->next = xtensa_cores;
193     xtensa_cores = node;
194     type.name = g_strdup_printf(XTENSA_CPU_TYPE_NAME("%s"), node->config->name);
195     type_register(&type);
196     g_free((gpointer)type.name);
197 }
198 
199 static uint32_t check_hw_breakpoints(CPUXtensaState *env)
200 {
201     unsigned i;
202 
203     for (i = 0; i < env->config->ndbreak; ++i) {
204         if (env->cpu_watchpoint[i] &&
205                 env->cpu_watchpoint[i]->flags & BP_WATCHPOINT_HIT) {
206             return DEBUGCAUSE_DB | (i << DEBUGCAUSE_DBNUM_SHIFT);
207         }
208     }
209     return 0;
210 }
211 
212 void xtensa_breakpoint_handler(CPUState *cs)
213 {
214     XtensaCPU *cpu = XTENSA_CPU(cs);
215     CPUXtensaState *env = &cpu->env;
216 
217     if (cs->watchpoint_hit) {
218         if (cs->watchpoint_hit->flags & BP_CPU) {
219             uint32_t cause;
220 
221             cs->watchpoint_hit = NULL;
222             cause = check_hw_breakpoints(env);
223             if (cause) {
224                 debug_exception_env(env, cause);
225             }
226             cpu_loop_exit_noexc(cs);
227         }
228     }
229 }
230 
231 void xtensa_cpu_list(FILE *f, fprintf_function cpu_fprintf)
232 {
233     XtensaConfigList *core = xtensa_cores;
234     cpu_fprintf(f, "Available CPUs:\n");
235     for (; core; core = core->next) {
236         cpu_fprintf(f, "  %s\n", core->config->name);
237     }
238 }
239 
240 #ifdef CONFIG_USER_ONLY
241 
242 int xtensa_cpu_handle_mmu_fault(CPUState *cs, vaddr address, int size, int rw,
243                                 int mmu_idx)
244 {
245     XtensaCPU *cpu = XTENSA_CPU(cs);
246     CPUXtensaState *env = &cpu->env;
247 
248     qemu_log_mask(CPU_LOG_INT,
249                   "%s: rw = %d, address = 0x%08" VADDR_PRIx ", size = %d\n",
250                   __func__, rw, address, size);
251     env->sregs[EXCVADDR] = address;
252     env->sregs[EXCCAUSE] = rw ? STORE_PROHIBITED_CAUSE : LOAD_PROHIBITED_CAUSE;
253     cs->exception_index = EXC_USER;
254     return 1;
255 }
256 
257 #else
258 
259 void xtensa_cpu_do_unaligned_access(CPUState *cs,
260                                     vaddr addr, MMUAccessType access_type,
261                                     int mmu_idx, uintptr_t retaddr)
262 {
263     XtensaCPU *cpu = XTENSA_CPU(cs);
264     CPUXtensaState *env = &cpu->env;
265 
266     if (xtensa_option_enabled(env->config, XTENSA_OPTION_UNALIGNED_EXCEPTION) &&
267         !xtensa_option_enabled(env->config, XTENSA_OPTION_HW_ALIGNMENT)) {
268         cpu_restore_state(CPU(cpu), retaddr, true);
269         HELPER(exception_cause_vaddr)(env,
270                                       env->pc, LOAD_STORE_ALIGNMENT_CAUSE,
271                                       addr);
272     }
273 }
274 
275 void tlb_fill(CPUState *cs, target_ulong vaddr, int size,
276               MMUAccessType access_type, int mmu_idx, uintptr_t retaddr)
277 {
278     XtensaCPU *cpu = XTENSA_CPU(cs);
279     CPUXtensaState *env = &cpu->env;
280     uint32_t paddr;
281     uint32_t page_size;
282     unsigned access;
283     int ret = xtensa_get_physical_addr(env, true, vaddr, access_type, mmu_idx,
284                                        &paddr, &page_size, &access);
285 
286     qemu_log_mask(CPU_LOG_MMU, "%s(%08x, %d, %d) -> %08x, ret = %d\n",
287                   __func__, vaddr, access_type, mmu_idx, paddr, ret);
288 
289     if (ret == 0) {
290         tlb_set_page(cs,
291                      vaddr & TARGET_PAGE_MASK,
292                      paddr & TARGET_PAGE_MASK,
293                      access, mmu_idx, page_size);
294     } else {
295         cpu_restore_state(cs, retaddr, true);
296         HELPER(exception_cause_vaddr)(env, env->pc, ret, vaddr);
297     }
298 }
299 
300 void xtensa_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr, vaddr addr,
301                                       unsigned size, MMUAccessType access_type,
302                                       int mmu_idx, MemTxAttrs attrs,
303                                       MemTxResult response, uintptr_t retaddr)
304 {
305     XtensaCPU *cpu = XTENSA_CPU(cs);
306     CPUXtensaState *env = &cpu->env;
307 
308     cpu_restore_state(cs, retaddr, true);
309     HELPER(exception_cause_vaddr)(env, env->pc,
310                                   access_type == MMU_INST_FETCH ?
311                                   INSTR_PIF_ADDR_ERROR_CAUSE :
312                                   LOAD_STORE_PIF_ADDR_ERROR_CAUSE,
313                                   addr);
314 }
315 
316 void xtensa_runstall(CPUXtensaState *env, bool runstall)
317 {
318     CPUState *cpu = CPU(xtensa_env_get_cpu(env));
319 
320     env->runstall = runstall;
321     cpu->halted = runstall;
322     if (runstall) {
323         cpu_interrupt(cpu, CPU_INTERRUPT_HALT);
324     } else {
325         qemu_cpu_kick(cpu);
326     }
327 }
328 #endif
329