xref: /openbmc/qemu/target/xtensa/helper.c (revision 520e210c)
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/host-utils.h"
34 
35 static struct XtensaConfigList *xtensa_cores;
36 
37 static void xtensa_core_class_init(ObjectClass *oc, void *data)
38 {
39     CPUClass *cc = CPU_CLASS(oc);
40     XtensaCPUClass *xcc = XTENSA_CPU_CLASS(oc);
41     const XtensaConfig *config = data;
42 
43     xcc->config = config;
44 
45     /* Use num_core_regs to see only non-privileged registers in an unmodified
46      * gdb. Use num_regs to see all registers. gdb modification is required
47      * for that: reset bit 0 in the 'flags' field of the registers definitions
48      * in the gdb/xtensa-config.c inside gdb source tree or inside gdb overlay.
49      */
50     cc->gdb_num_core_regs = config->gdb_regmap.num_regs;
51 }
52 
53 static void init_libisa(XtensaConfig *config)
54 {
55     unsigned i, j;
56     unsigned opcodes;
57     unsigned formats;
58 
59     config->isa = xtensa_isa_init(config->isa_internal, NULL, NULL);
60     assert(xtensa_isa_maxlength(config->isa) <= MAX_INSN_LENGTH);
61     opcodes = xtensa_isa_num_opcodes(config->isa);
62     formats = xtensa_isa_num_formats(config->isa);
63     config->opcode_ops = g_new(XtensaOpcodeOps *, opcodes);
64 
65     for (i = 0; i < formats; ++i) {
66         assert(xtensa_format_num_slots(config->isa, i) <= MAX_INSN_SLOTS);
67     }
68 
69     for (i = 0; i < opcodes; ++i) {
70         const char *opc_name = xtensa_opcode_name(config->isa, i);
71         XtensaOpcodeOps *ops = NULL;
72 
73         assert(xtensa_opcode_num_operands(config->isa, i) <= MAX_OPCODE_ARGS);
74         if (!config->opcode_translators) {
75             ops = xtensa_find_opcode_ops(&xtensa_core_opcodes, opc_name);
76         } else {
77             for (j = 0; !ops && config->opcode_translators[j]; ++j) {
78                 ops = xtensa_find_opcode_ops(config->opcode_translators[j],
79                                              opc_name);
80             }
81         }
82 #ifdef DEBUG
83         if (ops == NULL) {
84             fprintf(stderr,
85                     "opcode translator not found for %s's opcode '%s'\n",
86                     config->name, opc_name);
87         }
88 #endif
89         config->opcode_ops[i] = ops;
90     }
91 }
92 
93 void xtensa_finalize_config(XtensaConfig *config)
94 {
95     if (config->isa_internal) {
96         init_libisa(config);
97     }
98 
99     if (config->gdb_regmap.num_regs == 0 ||
100         config->gdb_regmap.num_core_regs == 0) {
101         unsigned n_regs = 0;
102         unsigned n_core_regs = 0;
103 
104         xtensa_count_regs(config, &n_regs, &n_core_regs);
105         if (config->gdb_regmap.num_regs == 0) {
106             config->gdb_regmap.num_regs = n_regs;
107         }
108         if (config->gdb_regmap.num_core_regs == 0) {
109             config->gdb_regmap.num_core_regs = n_core_regs;
110         }
111     }
112 }
113 
114 void xtensa_register_core(XtensaConfigList *node)
115 {
116     TypeInfo type = {
117         .parent = TYPE_XTENSA_CPU,
118         .class_init = xtensa_core_class_init,
119         .class_data = (void *)node->config,
120     };
121 
122     node->next = xtensa_cores;
123     xtensa_cores = node;
124     type.name = g_strdup_printf(XTENSA_CPU_TYPE_NAME("%s"), node->config->name);
125     type_register(&type);
126     g_free((gpointer)type.name);
127 }
128 
129 static uint32_t check_hw_breakpoints(CPUXtensaState *env)
130 {
131     unsigned i;
132 
133     for (i = 0; i < env->config->ndbreak; ++i) {
134         if (env->cpu_watchpoint[i] &&
135                 env->cpu_watchpoint[i]->flags & BP_WATCHPOINT_HIT) {
136             return DEBUGCAUSE_DB | (i << DEBUGCAUSE_DBNUM_SHIFT);
137         }
138     }
139     return 0;
140 }
141 
142 void xtensa_breakpoint_handler(CPUState *cs)
143 {
144     XtensaCPU *cpu = XTENSA_CPU(cs);
145     CPUXtensaState *env = &cpu->env;
146 
147     if (cs->watchpoint_hit) {
148         if (cs->watchpoint_hit->flags & BP_CPU) {
149             uint32_t cause;
150 
151             cs->watchpoint_hit = NULL;
152             cause = check_hw_breakpoints(env);
153             if (cause) {
154                 debug_exception_env(env, cause);
155             }
156             cpu_loop_exit_noexc(cs);
157         }
158     }
159 }
160 
161 void xtensa_cpu_list(FILE *f, fprintf_function cpu_fprintf)
162 {
163     XtensaConfigList *core = xtensa_cores;
164     cpu_fprintf(f, "Available CPUs:\n");
165     for (; core; core = core->next) {
166         cpu_fprintf(f, "  %s\n", core->config->name);
167     }
168 }
169 
170 #ifdef CONFIG_USER_ONLY
171 
172 int xtensa_cpu_handle_mmu_fault(CPUState *cs, vaddr address, int size, int rw,
173                                 int mmu_idx)
174 {
175     XtensaCPU *cpu = XTENSA_CPU(cs);
176     CPUXtensaState *env = &cpu->env;
177 
178     qemu_log_mask(CPU_LOG_INT,
179                   "%s: rw = %d, address = 0x%08" VADDR_PRIx ", size = %d\n",
180                   __func__, rw, address, size);
181     env->sregs[EXCVADDR] = address;
182     env->sregs[EXCCAUSE] = rw ? STORE_PROHIBITED_CAUSE : LOAD_PROHIBITED_CAUSE;
183     cs->exception_index = EXC_USER;
184     return 1;
185 }
186 
187 #else
188 
189 void xtensa_cpu_do_unaligned_access(CPUState *cs,
190                                     vaddr addr, MMUAccessType access_type,
191                                     int mmu_idx, uintptr_t retaddr)
192 {
193     XtensaCPU *cpu = XTENSA_CPU(cs);
194     CPUXtensaState *env = &cpu->env;
195 
196     if (xtensa_option_enabled(env->config, XTENSA_OPTION_UNALIGNED_EXCEPTION) &&
197         !xtensa_option_enabled(env->config, XTENSA_OPTION_HW_ALIGNMENT)) {
198         cpu_restore_state(CPU(cpu), retaddr, true);
199         HELPER(exception_cause_vaddr)(env,
200                                       env->pc, LOAD_STORE_ALIGNMENT_CAUSE,
201                                       addr);
202     }
203 }
204 
205 void tlb_fill(CPUState *cs, target_ulong vaddr, int size,
206               MMUAccessType access_type, int mmu_idx, uintptr_t retaddr)
207 {
208     XtensaCPU *cpu = XTENSA_CPU(cs);
209     CPUXtensaState *env = &cpu->env;
210     uint32_t paddr;
211     uint32_t page_size;
212     unsigned access;
213     int ret = xtensa_get_physical_addr(env, true, vaddr, access_type, mmu_idx,
214                                        &paddr, &page_size, &access);
215 
216     qemu_log_mask(CPU_LOG_MMU, "%s(%08x, %d, %d) -> %08x, ret = %d\n",
217                   __func__, vaddr, access_type, mmu_idx, paddr, ret);
218 
219     if (ret == 0) {
220         tlb_set_page(cs,
221                      vaddr & TARGET_PAGE_MASK,
222                      paddr & TARGET_PAGE_MASK,
223                      access, mmu_idx, page_size);
224     } else {
225         cpu_restore_state(cs, retaddr, true);
226         HELPER(exception_cause_vaddr)(env, env->pc, ret, vaddr);
227     }
228 }
229 
230 void xtensa_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr, vaddr addr,
231                                       unsigned size, MMUAccessType access_type,
232                                       int mmu_idx, MemTxAttrs attrs,
233                                       MemTxResult response, uintptr_t retaddr)
234 {
235     XtensaCPU *cpu = XTENSA_CPU(cs);
236     CPUXtensaState *env = &cpu->env;
237 
238     cpu_restore_state(cs, retaddr, true);
239     HELPER(exception_cause_vaddr)(env, env->pc,
240                                   access_type == MMU_INST_FETCH ?
241                                   INSTR_PIF_ADDR_ERROR_CAUSE :
242                                   LOAD_STORE_PIF_ADDR_ERROR_CAUSE,
243                                   addr);
244 }
245 
246 void xtensa_runstall(CPUXtensaState *env, bool runstall)
247 {
248     CPUState *cpu = CPU(xtensa_env_get_cpu(env));
249 
250     env->runstall = runstall;
251     cpu->halted = runstall;
252     if (runstall) {
253         cpu_interrupt(cpu, CPU_INTERRUPT_HALT);
254     } else {
255         qemu_cpu_kick(cpu);
256     }
257 }
258 #endif
259