xref: /openbmc/qemu/target/s390x/cpu.c (revision c1774bdb)
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 static void s390_query_cpu_fast(CPUState *cpu, CpuInfoFast *value)
144 {
145     S390CPU *s390_cpu = S390_CPU(cpu);
146 
147     value->u.s390x.cpu_state = s390_cpu->env.cpu_state;
148 }
149 
150 /* S390CPUClass::reset() */
151 static void s390_cpu_reset(CPUState *s, cpu_reset_type type)
152 {
153     S390CPU *cpu = S390_CPU(s);
154     S390CPUClass *scc = S390_CPU_GET_CLASS(cpu);
155     CPUS390XState *env = &cpu->env;
156     DeviceState *dev = DEVICE(s);
157 
158     scc->parent_reset(dev);
159     cpu->env.sigp_order = 0;
160     s390_cpu_set_state(S390_CPU_STATE_STOPPED, cpu);
161 
162     switch (type) {
163     case S390_CPU_RESET_CLEAR:
164         memset(env, 0, offsetof(CPUS390XState, start_initial_reset_fields));
165         /* fall through */
166     case S390_CPU_RESET_INITIAL:
167         /* initial reset does not clear everything! */
168         memset(&env->start_initial_reset_fields, 0,
169                offsetof(CPUS390XState, start_normal_reset_fields) -
170                offsetof(CPUS390XState, start_initial_reset_fields));
171 
172         /* architectured initial value for Breaking-Event-Address register */
173         env->gbea = 1;
174 
175         /* architectured initial values for CR 0 and 14 */
176         env->cregs[0] = CR0_RESET;
177         env->cregs[14] = CR14_RESET;
178 
179 #if defined(CONFIG_USER_ONLY)
180         /* user mode should always be allowed to use the full FPU */
181         env->cregs[0] |= CR0_AFP;
182         if (s390_has_feat(S390_FEAT_VECTOR)) {
183             env->cregs[0] |= CR0_VECTOR;
184         }
185 #endif
186 
187         /* tininess for underflow is detected before rounding */
188         set_float_detect_tininess(float_tininess_before_rounding,
189                                   &env->fpu_status);
190        /* fall through */
191     case S390_CPU_RESET_NORMAL:
192         env->psw.mask &= ~PSW_MASK_RI;
193         memset(&env->start_normal_reset_fields, 0,
194                offsetof(CPUS390XState, end_reset_fields) -
195                offsetof(CPUS390XState, start_normal_reset_fields));
196 
197         env->pfault_token = -1UL;
198         env->bpbc = false;
199         break;
200     default:
201         g_assert_not_reached();
202     }
203 
204     /* Reset state inside the kernel that we cannot access yet from QEMU. */
205     if (kvm_enabled()) {
206         switch (type) {
207         case S390_CPU_RESET_CLEAR:
208             kvm_s390_reset_vcpu_clear(cpu);
209             break;
210         case S390_CPU_RESET_INITIAL:
211             kvm_s390_reset_vcpu_initial(cpu);
212             break;
213         case S390_CPU_RESET_NORMAL:
214             kvm_s390_reset_vcpu_normal(cpu);
215             break;
216         }
217     }
218 }
219 
220 static void s390_cpu_disas_set_info(CPUState *cpu, disassemble_info *info)
221 {
222     info->mach = bfd_mach_s390_64;
223     info->cap_arch = CS_ARCH_SYSZ;
224     info->cap_insn_unit = 2;
225     info->cap_insn_split = 6;
226 }
227 
228 static void s390_cpu_realizefn(DeviceState *dev, Error **errp)
229 {
230     CPUState *cs = CPU(dev);
231     S390CPUClass *scc = S390_CPU_GET_CLASS(dev);
232     Error *err = NULL;
233 
234     /* the model has to be realized before qemu_init_vcpu() due to kvm */
235     s390_realize_cpu_model(cs, &err);
236     if (err) {
237         goto out;
238     }
239 
240 #if !defined(CONFIG_USER_ONLY)
241     if (!s390_cpu_realize_sysemu(dev, &err)) {
242         goto out;
243     }
244 #endif
245 
246     cpu_exec_realizefn(cs, &err);
247     if (err != NULL) {
248         goto out;
249     }
250 
251 #if !defined(CONFIG_USER_ONLY)
252     qemu_register_reset(s390_cpu_machine_reset_cb, S390_CPU(dev));
253 #endif
254     s390_cpu_gdb_init(cs);
255     qemu_init_vcpu(cs);
256 
257     /*
258      * KVM requires the initial CPU reset ioctl to be executed on the target
259      * CPU thread. CPU hotplug under single-threaded TCG will not work with
260      * run_on_cpu(), as run_on_cpu() will not work properly if called while
261      * the main thread is already running but the CPU hasn't been realized.
262      */
263     if (kvm_enabled()) {
264         run_on_cpu(cs, s390_do_cpu_full_reset, RUN_ON_CPU_NULL);
265     } else {
266         cpu_reset(cs);
267     }
268 
269     scc->parent_realize(dev, &err);
270 out:
271     error_propagate(errp, err);
272 }
273 
274 static void s390_cpu_initfn(Object *obj)
275 {
276     CPUState *cs = CPU(obj);
277 
278     cs->exception_index = EXCP_HLT;
279 
280 #if !defined(CONFIG_USER_ONLY)
281     s390_cpu_init_sysemu(obj);
282 #endif
283 }
284 
285 static gchar *s390_gdb_arch_name(CPUState *cs)
286 {
287     return g_strdup("s390:64-bit");
288 }
289 
290 static Property s390x_cpu_properties[] = {
291 #if !defined(CONFIG_USER_ONLY)
292     DEFINE_PROP_UINT32("core-id", S390CPU, env.core_id, 0),
293 #endif
294     DEFINE_PROP_END_OF_LIST()
295 };
296 
297 static void s390_cpu_reset_full(DeviceState *dev)
298 {
299     CPUState *s = CPU(dev);
300     return s390_cpu_reset(s, S390_CPU_RESET_CLEAR);
301 }
302 
303 #ifdef CONFIG_TCG
304 #include "hw/core/tcg-cpu-ops.h"
305 
306 static const struct TCGCPUOps s390_tcg_ops = {
307     .initialize = s390x_translate_init,
308     .restore_state_to_opc = s390x_restore_state_to_opc,
309 
310 #ifdef CONFIG_USER_ONLY
311     .record_sigsegv = s390_cpu_record_sigsegv,
312     .record_sigbus = s390_cpu_record_sigbus,
313 #else
314     .tlb_fill = s390_cpu_tlb_fill,
315     .cpu_exec_interrupt = s390_cpu_exec_interrupt,
316     .do_interrupt = s390_cpu_do_interrupt,
317     .debug_excp_handler = s390x_cpu_debug_excp_handler,
318     .do_unaligned_access = s390x_cpu_do_unaligned_access,
319 #endif /* !CONFIG_USER_ONLY */
320 };
321 #endif /* CONFIG_TCG */
322 
323 static void s390_cpu_class_init(ObjectClass *oc, void *data)
324 {
325     S390CPUClass *scc = S390_CPU_CLASS(oc);
326     CPUClass *cc = CPU_CLASS(scc);
327     DeviceClass *dc = DEVICE_CLASS(oc);
328 
329     device_class_set_parent_realize(dc, s390_cpu_realizefn,
330                                     &scc->parent_realize);
331     device_class_set_props(dc, s390x_cpu_properties);
332     dc->user_creatable = true;
333 
334     device_class_set_parent_reset(dc, s390_cpu_reset_full, &scc->parent_reset);
335 
336     scc->reset = s390_cpu_reset;
337     cc->class_by_name = s390_cpu_class_by_name,
338     cc->has_work = s390_cpu_has_work;
339     cc->dump_state = s390_cpu_dump_state;
340     cc->query_cpu_fast = s390_query_cpu_fast;
341     cc->set_pc = s390_cpu_set_pc;
342     cc->get_pc = s390_cpu_get_pc;
343     cc->gdb_read_register = s390_cpu_gdb_read_register;
344     cc->gdb_write_register = s390_cpu_gdb_write_register;
345 #ifndef CONFIG_USER_ONLY
346     s390_cpu_class_init_sysemu(cc);
347 #endif
348     cc->disas_set_info = s390_cpu_disas_set_info;
349     cc->gdb_num_core_regs = S390_NUM_CORE_REGS;
350     cc->gdb_core_xml_file = "s390x-core64.xml";
351     cc->gdb_arch_name = s390_gdb_arch_name;
352 
353     s390_cpu_model_class_register_props(oc);
354 
355 #ifdef CONFIG_TCG
356     cc->tcg_ops = &s390_tcg_ops;
357 #endif /* CONFIG_TCG */
358 }
359 
360 static const TypeInfo s390_cpu_type_info = {
361     .name = TYPE_S390_CPU,
362     .parent = TYPE_CPU,
363     .instance_size = sizeof(S390CPU),
364     .instance_align = __alignof__(S390CPU),
365     .instance_init = s390_cpu_initfn,
366 
367 #ifndef CONFIG_USER_ONLY
368     .instance_finalize = s390_cpu_finalize,
369 #endif /* !CONFIG_USER_ONLY */
370 
371     .abstract = true,
372     .class_size = sizeof(S390CPUClass),
373     .class_init = s390_cpu_class_init,
374 };
375 
376 static void s390_cpu_register_types(void)
377 {
378     type_register_static(&s390_cpu_type_info);
379 }
380 
381 type_init(s390_cpu_register_types)
382