xref: /openbmc/qemu/target/s390x/cpu.c (revision 86d063fa)
1 /*
2  * QEMU S/390 CPU
3  *
4  * Copyright (c) 2009 Ulrich Hecht
5  * Copyright (c) 2011 Alexander Graf
6  * Copyright (c) 2012 SUSE LINUX Products GmbH
7  * Copyright (c) 2012 IBM Corp.
8  *
9  * This program is free software; you can redistribute it and/or modify
10  * it under the terms of the GNU General Public License as published by
11  * the Free Software Foundation; either version 2 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17  * General Public License for more details.
18  *
19  * You should have received a copy of the GNU General Public License
20  * along with this program; if not, see <http://www.gnu.org/licenses/>.
21  */
22 
23 #include "qemu/osdep.h"
24 #include "qapi/error.h"
25 #include "cpu.h"
26 #include "s390x-internal.h"
27 #include "kvm/kvm_s390x.h"
28 #include "sysemu/kvm.h"
29 #include "qemu/module.h"
30 #include "trace.h"
31 #include "qapi/qapi-types-machine.h"
32 #include "sysemu/hw_accel.h"
33 #include "hw/qdev-properties.h"
34 #include "fpu/softfloat-helpers.h"
35 #include "disas/capstone.h"
36 #include "sysemu/tcg.h"
37 #ifndef CONFIG_USER_ONLY
38 #include "sysemu/reset.h"
39 #endif
40 
41 #define CR0_RESET       0xE0UL
42 #define CR14_RESET      0xC2000000UL;
43 
44 #ifndef CONFIG_USER_ONLY
45 static bool is_early_exception_psw(uint64_t mask, uint64_t addr)
46 {
47     if (mask & PSW_MASK_RESERVED) {
48         return true;
49     }
50 
51     switch (mask & (PSW_MASK_32 | PSW_MASK_64)) {
52     case 0:
53         return addr & ~0xffffffULL;
54     case PSW_MASK_32:
55         return addr & ~0x7fffffffULL;
56     case PSW_MASK_32 | PSW_MASK_64:
57         return false;
58     default: /* PSW_MASK_64 */
59         return true;
60     }
61 }
62 #endif
63 
64 void s390_cpu_set_psw(CPUS390XState *env, uint64_t mask, uint64_t addr)
65 {
66 #ifndef CONFIG_USER_ONLY
67     uint64_t old_mask = env->psw.mask;
68 #endif
69 
70     env->psw.addr = addr;
71     env->psw.mask = mask;
72 
73     /* KVM will handle all WAITs and trigger a WAIT exit on disabled_wait */
74     if (!tcg_enabled()) {
75         return;
76     }
77     env->cc_op = (mask >> 44) & 3;
78 
79 #ifndef CONFIG_USER_ONLY
80     if (is_early_exception_psw(mask, addr)) {
81         env->int_pgm_ilen = 0;
82         trigger_pgm_exception(env, PGM_SPECIFICATION);
83         return;
84     }
85 
86     if ((old_mask ^ mask) & PSW_MASK_PER) {
87         s390_cpu_recompute_watchpoints(env_cpu(env));
88     }
89 
90     if (mask & PSW_MASK_WAIT) {
91         s390_handle_wait(env_archcpu(env));
92     }
93 #endif
94 }
95 
96 uint64_t s390_cpu_get_psw_mask(CPUS390XState *env)
97 {
98     uint64_t r = env->psw.mask;
99 
100     if (tcg_enabled()) {
101         uint64_t cc = calc_cc(env, env->cc_op, env->cc_src,
102                               env->cc_dst, env->cc_vr);
103 
104         assert(cc <= 3);
105         r &= ~PSW_MASK_CC;
106         r |= cc << 44;
107     }
108 
109     return r;
110 }
111 
112 static void s390_cpu_set_pc(CPUState *cs, vaddr value)
113 {
114     S390CPU *cpu = S390_CPU(cs);
115 
116     cpu->env.psw.addr = value;
117 }
118 
119 static vaddr s390_cpu_get_pc(CPUState *cs)
120 {
121     S390CPU *cpu = S390_CPU(cs);
122 
123     return cpu->env.psw.addr;
124 }
125 
126 static bool s390_cpu_has_work(CPUState *cs)
127 {
128     S390CPU *cpu = S390_CPU(cs);
129 
130     /* STOPPED cpus can never wake up */
131     if (s390_cpu_get_state(cpu) != S390_CPU_STATE_LOAD &&
132         s390_cpu_get_state(cpu) != S390_CPU_STATE_OPERATING) {
133         return false;
134     }
135 
136     if (!(cs->interrupt_request & CPU_INTERRUPT_HARD)) {
137         return false;
138     }
139 
140     return s390_cpu_has_int(cpu);
141 }
142 
143 /* S390CPUClass::reset() */
144 static void s390_cpu_reset(CPUState *s, cpu_reset_type type)
145 {
146     S390CPU *cpu = S390_CPU(s);
147     S390CPUClass *scc = S390_CPU_GET_CLASS(cpu);
148     CPUS390XState *env = &cpu->env;
149     DeviceState *dev = DEVICE(s);
150 
151     scc->parent_reset(dev);
152     cpu->env.sigp_order = 0;
153     s390_cpu_set_state(S390_CPU_STATE_STOPPED, cpu);
154 
155     switch (type) {
156     case S390_CPU_RESET_CLEAR:
157         memset(env, 0, offsetof(CPUS390XState, start_initial_reset_fields));
158         /* fall through */
159     case S390_CPU_RESET_INITIAL:
160         /* initial reset does not clear everything! */
161         memset(&env->start_initial_reset_fields, 0,
162                offsetof(CPUS390XState, start_normal_reset_fields) -
163                offsetof(CPUS390XState, start_initial_reset_fields));
164 
165         /* architectured initial value for Breaking-Event-Address register */
166         env->gbea = 1;
167 
168         /* architectured initial values for CR 0 and 14 */
169         env->cregs[0] = CR0_RESET;
170         env->cregs[14] = CR14_RESET;
171 
172 #if defined(CONFIG_USER_ONLY)
173         /* user mode should always be allowed to use the full FPU */
174         env->cregs[0] |= CR0_AFP;
175         if (s390_has_feat(S390_FEAT_VECTOR)) {
176             env->cregs[0] |= CR0_VECTOR;
177         }
178 #endif
179 
180         /* tininess for underflow is detected before rounding */
181         set_float_detect_tininess(float_tininess_before_rounding,
182                                   &env->fpu_status);
183        /* fall through */
184     case S390_CPU_RESET_NORMAL:
185         env->psw.mask &= ~PSW_MASK_RI;
186         memset(&env->start_normal_reset_fields, 0,
187                offsetof(CPUS390XState, end_reset_fields) -
188                offsetof(CPUS390XState, start_normal_reset_fields));
189 
190         env->pfault_token = -1UL;
191         env->bpbc = false;
192         break;
193     default:
194         g_assert_not_reached();
195     }
196 
197     /* Reset state inside the kernel that we cannot access yet from QEMU. */
198     if (kvm_enabled()) {
199         switch (type) {
200         case S390_CPU_RESET_CLEAR:
201             kvm_s390_reset_vcpu_clear(cpu);
202             break;
203         case S390_CPU_RESET_INITIAL:
204             kvm_s390_reset_vcpu_initial(cpu);
205             break;
206         case S390_CPU_RESET_NORMAL:
207             kvm_s390_reset_vcpu_normal(cpu);
208             break;
209         }
210     }
211 }
212 
213 static void s390_cpu_disas_set_info(CPUState *cpu, disassemble_info *info)
214 {
215     info->mach = bfd_mach_s390_64;
216     info->cap_arch = CS_ARCH_SYSZ;
217     info->cap_insn_unit = 2;
218     info->cap_insn_split = 6;
219 }
220 
221 static void s390_cpu_realizefn(DeviceState *dev, Error **errp)
222 {
223     CPUState *cs = CPU(dev);
224     S390CPUClass *scc = S390_CPU_GET_CLASS(dev);
225     Error *err = NULL;
226 
227     /* the model has to be realized before qemu_init_vcpu() due to kvm */
228     s390_realize_cpu_model(cs, &err);
229     if (err) {
230         goto out;
231     }
232 
233 #if !defined(CONFIG_USER_ONLY)
234     if (!s390_cpu_realize_sysemu(dev, &err)) {
235         goto out;
236     }
237 #endif
238 
239     cpu_exec_realizefn(cs, &err);
240     if (err != NULL) {
241         goto out;
242     }
243 
244 #if !defined(CONFIG_USER_ONLY)
245     qemu_register_reset(s390_cpu_machine_reset_cb, S390_CPU(dev));
246 #endif
247     s390_cpu_gdb_init(cs);
248     qemu_init_vcpu(cs);
249 
250     /*
251      * KVM requires the initial CPU reset ioctl to be executed on the target
252      * CPU thread. CPU hotplug under single-threaded TCG will not work with
253      * run_on_cpu(), as run_on_cpu() will not work properly if called while
254      * the main thread is already running but the CPU hasn't been realized.
255      */
256     if (kvm_enabled()) {
257         run_on_cpu(cs, s390_do_cpu_full_reset, RUN_ON_CPU_NULL);
258     } else {
259         cpu_reset(cs);
260     }
261 
262     scc->parent_realize(dev, &err);
263 out:
264     error_propagate(errp, err);
265 }
266 
267 static void s390_cpu_initfn(Object *obj)
268 {
269     CPUState *cs = CPU(obj);
270     S390CPU *cpu = S390_CPU(obj);
271 
272     cpu_set_cpustate_pointers(cpu);
273     cs->exception_index = EXCP_HLT;
274 
275 #if !defined(CONFIG_USER_ONLY)
276     s390_cpu_init_sysemu(obj);
277 #endif
278 }
279 
280 static gchar *s390_gdb_arch_name(CPUState *cs)
281 {
282     return g_strdup("s390:64-bit");
283 }
284 
285 static Property s390x_cpu_properties[] = {
286 #if !defined(CONFIG_USER_ONLY)
287     DEFINE_PROP_UINT32("core-id", S390CPU, env.core_id, 0),
288 #endif
289     DEFINE_PROP_END_OF_LIST()
290 };
291 
292 static void s390_cpu_reset_full(DeviceState *dev)
293 {
294     CPUState *s = CPU(dev);
295     return s390_cpu_reset(s, S390_CPU_RESET_CLEAR);
296 }
297 
298 #ifdef CONFIG_TCG
299 #include "hw/core/tcg-cpu-ops.h"
300 
301 static const struct TCGCPUOps s390_tcg_ops = {
302     .initialize = s390x_translate_init,
303     .restore_state_to_opc = s390x_restore_state_to_opc,
304 
305 #ifdef CONFIG_USER_ONLY
306     .record_sigsegv = s390_cpu_record_sigsegv,
307     .record_sigbus = s390_cpu_record_sigbus,
308 #else
309     .tlb_fill = s390_cpu_tlb_fill,
310     .cpu_exec_interrupt = s390_cpu_exec_interrupt,
311     .do_interrupt = s390_cpu_do_interrupt,
312     .debug_excp_handler = s390x_cpu_debug_excp_handler,
313     .do_unaligned_access = s390x_cpu_do_unaligned_access,
314 #endif /* !CONFIG_USER_ONLY */
315 };
316 #endif /* CONFIG_TCG */
317 
318 static void s390_cpu_class_init(ObjectClass *oc, void *data)
319 {
320     S390CPUClass *scc = S390_CPU_CLASS(oc);
321     CPUClass *cc = CPU_CLASS(scc);
322     DeviceClass *dc = DEVICE_CLASS(oc);
323 
324     device_class_set_parent_realize(dc, s390_cpu_realizefn,
325                                     &scc->parent_realize);
326     device_class_set_props(dc, s390x_cpu_properties);
327     dc->user_creatable = true;
328 
329     device_class_set_parent_reset(dc, s390_cpu_reset_full, &scc->parent_reset);
330 
331     scc->reset = s390_cpu_reset;
332     cc->class_by_name = s390_cpu_class_by_name,
333     cc->has_work = s390_cpu_has_work;
334     cc->dump_state = s390_cpu_dump_state;
335     cc->set_pc = s390_cpu_set_pc;
336     cc->get_pc = s390_cpu_get_pc;
337     cc->gdb_read_register = s390_cpu_gdb_read_register;
338     cc->gdb_write_register = s390_cpu_gdb_write_register;
339 #ifndef CONFIG_USER_ONLY
340     s390_cpu_class_init_sysemu(cc);
341 #endif
342     cc->disas_set_info = s390_cpu_disas_set_info;
343     cc->gdb_num_core_regs = S390_NUM_CORE_REGS;
344     cc->gdb_core_xml_file = "s390x-core64.xml";
345     cc->gdb_arch_name = s390_gdb_arch_name;
346 
347     s390_cpu_model_class_register_props(oc);
348 
349 #ifdef CONFIG_TCG
350     cc->tcg_ops = &s390_tcg_ops;
351 #endif /* CONFIG_TCG */
352 }
353 
354 static const TypeInfo s390_cpu_type_info = {
355     .name = TYPE_S390_CPU,
356     .parent = TYPE_CPU,
357     .instance_size = sizeof(S390CPU),
358     .instance_align = __alignof__(S390CPU),
359     .instance_init = s390_cpu_initfn,
360 
361 #ifndef CONFIG_USER_ONLY
362     .instance_finalize = s390_cpu_finalize,
363 #endif /* !CONFIG_USER_ONLY */
364 
365     .abstract = true,
366     .class_size = sizeof(S390CPUClass),
367     .class_init = s390_cpu_class_init,
368 };
369 
370 static void s390_cpu_register_types(void)
371 {
372     type_register_static(&s390_cpu_type_info);
373 }
374 
375 type_init(s390_cpu_register_types)
376