xref: /openbmc/qemu/target/riscv/cpu.h (revision 30b6852c)
1 /*
2  * QEMU RISC-V CPU
3  *
4  * Copyright (c) 2016-2017 Sagar Karandikar, sagark@eecs.berkeley.edu
5  * Copyright (c) 2017-2018 SiFive, Inc.
6  *
7  * This program is free software; you can redistribute it and/or modify it
8  * under the terms and conditions of the GNU General Public License,
9  * version 2 or later, as published by the Free Software Foundation.
10  *
11  * This program is distributed in the hope it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
14  * more details.
15  *
16  * You should have received a copy of the GNU General Public License along with
17  * this program.  If not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 #ifndef RISCV_CPU_H
21 #define RISCV_CPU_H
22 
23 #include "hw/core/cpu.h"
24 #include "hw/registerfields.h"
25 #include "exec/cpu-defs.h"
26 #include "fpu/softfloat-types.h"
27 #include "qom/object.h"
28 
29 #define TCG_GUEST_DEFAULT_MO 0
30 
31 #define TYPE_RISCV_CPU "riscv-cpu"
32 
33 #define RISCV_CPU_TYPE_SUFFIX "-" TYPE_RISCV_CPU
34 #define RISCV_CPU_TYPE_NAME(name) (name RISCV_CPU_TYPE_SUFFIX)
35 #define CPU_RESOLVING_TYPE TYPE_RISCV_CPU
36 
37 #define TYPE_RISCV_CPU_ANY              RISCV_CPU_TYPE_NAME("any")
38 #define TYPE_RISCV_CPU_BASE32           RISCV_CPU_TYPE_NAME("rv32")
39 #define TYPE_RISCV_CPU_BASE64           RISCV_CPU_TYPE_NAME("rv64")
40 #define TYPE_RISCV_CPU_IBEX             RISCV_CPU_TYPE_NAME("lowrisc-ibex")
41 #define TYPE_RISCV_CPU_SHAKTI_C         RISCV_CPU_TYPE_NAME("shakti-c")
42 #define TYPE_RISCV_CPU_SIFIVE_E31       RISCV_CPU_TYPE_NAME("sifive-e31")
43 #define TYPE_RISCV_CPU_SIFIVE_E34       RISCV_CPU_TYPE_NAME("sifive-e34")
44 #define TYPE_RISCV_CPU_SIFIVE_E51       RISCV_CPU_TYPE_NAME("sifive-e51")
45 #define TYPE_RISCV_CPU_SIFIVE_U34       RISCV_CPU_TYPE_NAME("sifive-u34")
46 #define TYPE_RISCV_CPU_SIFIVE_U54       RISCV_CPU_TYPE_NAME("sifive-u54")
47 
48 #if defined(TARGET_RISCV32)
49 # define TYPE_RISCV_CPU_BASE            TYPE_RISCV_CPU_BASE32
50 #elif defined(TARGET_RISCV64)
51 # define TYPE_RISCV_CPU_BASE            TYPE_RISCV_CPU_BASE64
52 #endif
53 
54 #define RV32 ((target_ulong)1 << (TARGET_LONG_BITS - 2))
55 #define RV64 ((target_ulong)2 << (TARGET_LONG_BITS - 2))
56 
57 #define RV(x) ((target_ulong)1 << (x - 'A'))
58 
59 #define RVI RV('I')
60 #define RVE RV('E') /* E and I are mutually exclusive */
61 #define RVM RV('M')
62 #define RVA RV('A')
63 #define RVF RV('F')
64 #define RVD RV('D')
65 #define RVV RV('V')
66 #define RVC RV('C')
67 #define RVS RV('S')
68 #define RVU RV('U')
69 #define RVH RV('H')
70 
71 /* S extension denotes that Supervisor mode exists, however it is possible
72    to have a core that support S mode but does not have an MMU and there
73    is currently no bit in misa to indicate whether an MMU exists or not
74    so a cpu features bitfield is required, likewise for optional PMP support */
75 enum {
76     RISCV_FEATURE_MMU,
77     RISCV_FEATURE_PMP,
78     RISCV_FEATURE_EPMP,
79     RISCV_FEATURE_MISA
80 };
81 
82 #define PRIV_VERSION_1_10_0 0x00011000
83 #define PRIV_VERSION_1_11_0 0x00011100
84 
85 #define VEXT_VERSION_0_07_1 0x00000701
86 
87 enum {
88     TRANSLATE_SUCCESS,
89     TRANSLATE_FAIL,
90     TRANSLATE_PMP_FAIL,
91     TRANSLATE_G_STAGE_FAIL
92 };
93 
94 #define MMU_USER_IDX 3
95 
96 #define MAX_RISCV_PMPS (16)
97 
98 typedef struct CPURISCVState CPURISCVState;
99 
100 #if !defined(CONFIG_USER_ONLY)
101 #include "pmp.h"
102 #endif
103 
104 #define RV_VLEN_MAX 256
105 
106 FIELD(VTYPE, VLMUL, 0, 2)
107 FIELD(VTYPE, VSEW, 2, 3)
108 FIELD(VTYPE, VEDIV, 5, 2)
109 FIELD(VTYPE, RESERVED, 7, sizeof(target_ulong) * 8 - 9)
110 FIELD(VTYPE, VILL, sizeof(target_ulong) * 8 - 1, 1)
111 
112 struct CPURISCVState {
113     target_ulong gpr[32];
114     uint64_t fpr[32]; /* assume both F and D extensions */
115 
116     /* vector coprocessor state. */
117     uint64_t vreg[32 * RV_VLEN_MAX / 64] QEMU_ALIGNED(16);
118     target_ulong vxrm;
119     target_ulong vxsat;
120     target_ulong vl;
121     target_ulong vstart;
122     target_ulong vtype;
123 
124     target_ulong pc;
125     target_ulong load_res;
126     target_ulong load_val;
127 
128     target_ulong frm;
129 
130     target_ulong badaddr;
131     target_ulong guest_phys_fault_addr;
132 
133     target_ulong priv_ver;
134     target_ulong bext_ver;
135     target_ulong vext_ver;
136     target_ulong misa;
137     target_ulong misa_mask;
138 
139     uint32_t features;
140 
141 #ifdef CONFIG_USER_ONLY
142     uint32_t elf_flags;
143 #endif
144 
145 #ifndef CONFIG_USER_ONLY
146     target_ulong priv;
147     /* This contains QEMU specific information about the virt state. */
148     target_ulong virt;
149     target_ulong resetvec;
150 
151     target_ulong mhartid;
152     /*
153      * For RV32 this is 32-bit mstatus and 32-bit mstatush.
154      * For RV64 this is a 64-bit mstatus.
155      */
156     uint64_t mstatus;
157 
158     target_ulong mip;
159 
160     uint32_t miclaim;
161 
162     target_ulong mie;
163     target_ulong mideleg;
164 
165     target_ulong satp;   /* since: priv-1.10.0 */
166     target_ulong stval;
167     target_ulong medeleg;
168 
169     target_ulong stvec;
170     target_ulong sepc;
171     target_ulong scause;
172 
173     target_ulong mtvec;
174     target_ulong mepc;
175     target_ulong mcause;
176     target_ulong mtval;  /* since: priv-1.10.0 */
177 
178     /* Hypervisor CSRs */
179     target_ulong hstatus;
180     target_ulong hedeleg;
181     target_ulong hideleg;
182     target_ulong hcounteren;
183     target_ulong htval;
184     target_ulong htinst;
185     target_ulong hgatp;
186     uint64_t htimedelta;
187 
188     /* Virtual CSRs */
189     /*
190      * For RV32 this is 32-bit vsstatus and 32-bit vsstatush.
191      * For RV64 this is a 64-bit vsstatus.
192      */
193     uint64_t vsstatus;
194     target_ulong vstvec;
195     target_ulong vsscratch;
196     target_ulong vsepc;
197     target_ulong vscause;
198     target_ulong vstval;
199     target_ulong vsatp;
200 
201     target_ulong mtval2;
202     target_ulong mtinst;
203 
204     /* HS Backup CSRs */
205     target_ulong stvec_hs;
206     target_ulong sscratch_hs;
207     target_ulong sepc_hs;
208     target_ulong scause_hs;
209     target_ulong stval_hs;
210     target_ulong satp_hs;
211     uint64_t mstatus_hs;
212 
213     /* Signals whether the current exception occurred with two-stage address
214        translation active. */
215     bool two_stage_lookup;
216 
217     target_ulong scounteren;
218     target_ulong mcounteren;
219 
220     target_ulong sscratch;
221     target_ulong mscratch;
222 
223     /* temporary htif regs */
224     uint64_t mfromhost;
225     uint64_t mtohost;
226     uint64_t timecmp;
227 
228     /* physical memory protection */
229     pmp_table_t pmp_state;
230     target_ulong mseccfg;
231 
232     /* machine specific rdtime callback */
233     uint64_t (*rdtime_fn)(uint32_t);
234     uint32_t rdtime_fn_arg;
235 
236     /* True if in debugger mode.  */
237     bool debugger;
238 #endif
239 
240     float_status fp_status;
241 
242     /* Fields from here on are preserved across CPU reset. */
243     QEMUTimer *timer; /* Internal timer */
244 };
245 
246 OBJECT_DECLARE_TYPE(RISCVCPU, RISCVCPUClass,
247                     RISCV_CPU)
248 
249 /**
250  * RISCVCPUClass:
251  * @parent_realize: The parent class' realize handler.
252  * @parent_reset: The parent class' reset handler.
253  *
254  * A RISCV CPU model.
255  */
256 struct RISCVCPUClass {
257     /*< private >*/
258     CPUClass parent_class;
259     /*< public >*/
260     DeviceRealize parent_realize;
261     DeviceReset parent_reset;
262 };
263 
264 /**
265  * RISCVCPU:
266  * @env: #CPURISCVState
267  *
268  * A RISCV CPU.
269  */
270 struct RISCVCPU {
271     /*< private >*/
272     CPUState parent_obj;
273     /*< public >*/
274     CPUNegativeOffsetState neg;
275     CPURISCVState env;
276 
277     char *dyn_csr_xml;
278 
279     /* Configuration Settings */
280     struct {
281         bool ext_i;
282         bool ext_e;
283         bool ext_g;
284         bool ext_m;
285         bool ext_a;
286         bool ext_f;
287         bool ext_d;
288         bool ext_c;
289         bool ext_s;
290         bool ext_u;
291         bool ext_h;
292         bool ext_v;
293         bool ext_zba;
294         bool ext_zbb;
295         bool ext_zbc;
296         bool ext_zbs;
297         bool ext_counters;
298         bool ext_ifencei;
299         bool ext_icsr;
300 
301         char *priv_spec;
302         char *user_spec;
303         char *bext_spec;
304         char *vext_spec;
305         uint16_t vlen;
306         uint16_t elen;
307         bool mmu;
308         bool pmp;
309         bool epmp;
310         uint64_t resetvec;
311     } cfg;
312 };
313 
314 static inline int riscv_has_ext(CPURISCVState *env, target_ulong ext)
315 {
316     return (env->misa & ext) != 0;
317 }
318 
319 static inline bool riscv_feature(CPURISCVState *env, int feature)
320 {
321     return env->features & (1ULL << feature);
322 }
323 
324 #include "cpu_user.h"
325 #include "cpu_bits.h"
326 
327 extern const char * const riscv_int_regnames[];
328 extern const char * const riscv_fpr_regnames[];
329 
330 const char *riscv_cpu_get_trap_name(target_ulong cause, bool async);
331 void riscv_cpu_do_interrupt(CPUState *cpu);
332 int riscv_cpu_write_elf64_note(WriteCoreDumpFunction f, CPUState *cs,
333                                int cpuid, void *opaque);
334 int riscv_cpu_write_elf32_note(WriteCoreDumpFunction f, CPUState *cs,
335                                int cpuid, void *opaque);
336 int riscv_cpu_gdb_read_register(CPUState *cpu, GByteArray *buf, int reg);
337 int riscv_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);
338 bool riscv_cpu_fp_enabled(CPURISCVState *env);
339 bool riscv_cpu_virt_enabled(CPURISCVState *env);
340 void riscv_cpu_set_virt_enabled(CPURISCVState *env, bool enable);
341 bool riscv_cpu_force_hs_excep_enabled(CPURISCVState *env);
342 void riscv_cpu_set_force_hs_excep(CPURISCVState *env, bool enable);
343 bool riscv_cpu_two_stage_lookup(int mmu_idx);
344 int riscv_cpu_mmu_index(CPURISCVState *env, bool ifetch);
345 hwaddr riscv_cpu_get_phys_page_debug(CPUState *cpu, vaddr addr);
346 void  riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
347                                     MMUAccessType access_type, int mmu_idx,
348                                     uintptr_t retaddr) QEMU_NORETURN;
349 bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
350                         MMUAccessType access_type, int mmu_idx,
351                         bool probe, uintptr_t retaddr);
352 void riscv_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr,
353                                      vaddr addr, unsigned size,
354                                      MMUAccessType access_type,
355                                      int mmu_idx, MemTxAttrs attrs,
356                                      MemTxResult response, uintptr_t retaddr);
357 char *riscv_isa_string(RISCVCPU *cpu);
358 void riscv_cpu_list(void);
359 
360 #define cpu_list riscv_cpu_list
361 #define cpu_mmu_index riscv_cpu_mmu_index
362 
363 #ifndef CONFIG_USER_ONLY
364 bool riscv_cpu_exec_interrupt(CPUState *cs, int interrupt_request);
365 void riscv_cpu_swap_hypervisor_regs(CPURISCVState *env);
366 int riscv_cpu_claim_interrupts(RISCVCPU *cpu, uint32_t interrupts);
367 uint32_t riscv_cpu_update_mip(RISCVCPU *cpu, uint32_t mask, uint32_t value);
368 #define BOOL_TO_MASK(x) (-!!(x)) /* helper for riscv_cpu_update_mip value */
369 void riscv_cpu_set_rdtime_fn(CPURISCVState *env, uint64_t (*fn)(uint32_t),
370                              uint32_t arg);
371 #endif
372 void riscv_cpu_set_mode(CPURISCVState *env, target_ulong newpriv);
373 
374 void riscv_translate_init(void);
375 void QEMU_NORETURN riscv_raise_exception(CPURISCVState *env,
376                                          uint32_t exception, uintptr_t pc);
377 
378 target_ulong riscv_cpu_get_fflags(CPURISCVState *env);
379 void riscv_cpu_set_fflags(CPURISCVState *env, target_ulong);
380 
381 #define TB_FLAGS_MMU_MASK   7
382 #define TB_FLAGS_PRIV_MMU_MASK                3
383 #define TB_FLAGS_PRIV_HYP_ACCESS_MASK   (1 << 2)
384 #define TB_FLAGS_MSTATUS_FS MSTATUS_FS
385 
386 typedef CPURISCVState CPUArchState;
387 typedef RISCVCPU ArchCPU;
388 #include "exec/cpu-all.h"
389 
390 FIELD(TB_FLAGS, VL_EQ_VLMAX, 2, 1)
391 FIELD(TB_FLAGS, LMUL, 3, 2)
392 FIELD(TB_FLAGS, SEW, 5, 3)
393 FIELD(TB_FLAGS, VILL, 8, 1)
394 /* Is a Hypervisor instruction load/store allowed? */
395 FIELD(TB_FLAGS, HLSX, 9, 1)
396 FIELD(TB_FLAGS, MSTATUS_HS_FS, 10, 2)
397 
398 bool riscv_cpu_is_32bit(CPURISCVState *env);
399 
400 /*
401  * A simplification for VLMAX
402  * = (1 << LMUL) * VLEN / (8 * (1 << SEW))
403  * = (VLEN << LMUL) / (8 << SEW)
404  * = (VLEN << LMUL) >> (SEW + 3)
405  * = VLEN >> (SEW + 3 - LMUL)
406  */
407 static inline uint32_t vext_get_vlmax(RISCVCPU *cpu, target_ulong vtype)
408 {
409     uint8_t sew, lmul;
410 
411     sew = FIELD_EX64(vtype, VTYPE, VSEW);
412     lmul = FIELD_EX64(vtype, VTYPE, VLMUL);
413     return cpu->cfg.vlen >> (sew + 3 - lmul);
414 }
415 
416 static inline void cpu_get_tb_cpu_state(CPURISCVState *env, target_ulong *pc,
417                                         target_ulong *cs_base, uint32_t *pflags)
418 {
419     uint32_t flags = 0;
420 
421     *pc = env->pc;
422     *cs_base = 0;
423 
424     if (riscv_has_ext(env, RVV)) {
425         uint32_t vlmax = vext_get_vlmax(env_archcpu(env), env->vtype);
426         bool vl_eq_vlmax = (env->vstart == 0) && (vlmax == env->vl);
427         flags = FIELD_DP32(flags, TB_FLAGS, VILL,
428                     FIELD_EX64(env->vtype, VTYPE, VILL));
429         flags = FIELD_DP32(flags, TB_FLAGS, SEW,
430                     FIELD_EX64(env->vtype, VTYPE, VSEW));
431         flags = FIELD_DP32(flags, TB_FLAGS, LMUL,
432                     FIELD_EX64(env->vtype, VTYPE, VLMUL));
433         flags = FIELD_DP32(flags, TB_FLAGS, VL_EQ_VLMAX, vl_eq_vlmax);
434     } else {
435         flags = FIELD_DP32(flags, TB_FLAGS, VILL, 1);
436     }
437 
438 #ifdef CONFIG_USER_ONLY
439     flags |= TB_FLAGS_MSTATUS_FS;
440 #else
441     flags |= cpu_mmu_index(env, 0);
442     if (riscv_cpu_fp_enabled(env)) {
443         flags |= env->mstatus & MSTATUS_FS;
444     }
445 
446     if (riscv_has_ext(env, RVH)) {
447         if (env->priv == PRV_M ||
448             (env->priv == PRV_S && !riscv_cpu_virt_enabled(env)) ||
449             (env->priv == PRV_U && !riscv_cpu_virt_enabled(env) &&
450                 get_field(env->hstatus, HSTATUS_HU))) {
451             flags = FIELD_DP32(flags, TB_FLAGS, HLSX, 1);
452         }
453 
454         flags = FIELD_DP32(flags, TB_FLAGS, MSTATUS_HS_FS,
455                            get_field(env->mstatus_hs, MSTATUS_FS));
456     }
457 #endif
458 
459     *pflags = flags;
460 }
461 
462 RISCVException riscv_csrrw(CPURISCVState *env, int csrno,
463                            target_ulong *ret_value,
464                            target_ulong new_value, target_ulong write_mask);
465 RISCVException riscv_csrrw_debug(CPURISCVState *env, int csrno,
466                                  target_ulong *ret_value,
467                                  target_ulong new_value,
468                                  target_ulong write_mask);
469 
470 static inline void riscv_csr_write(CPURISCVState *env, int csrno,
471                                    target_ulong val)
472 {
473     riscv_csrrw(env, csrno, NULL, val, MAKE_64BIT_MASK(0, TARGET_LONG_BITS));
474 }
475 
476 static inline target_ulong riscv_csr_read(CPURISCVState *env, int csrno)
477 {
478     target_ulong val = 0;
479     riscv_csrrw(env, csrno, &val, 0, 0);
480     return val;
481 }
482 
483 typedef RISCVException (*riscv_csr_predicate_fn)(CPURISCVState *env,
484                                                  int csrno);
485 typedef RISCVException (*riscv_csr_read_fn)(CPURISCVState *env, int csrno,
486                                             target_ulong *ret_value);
487 typedef RISCVException (*riscv_csr_write_fn)(CPURISCVState *env, int csrno,
488                                              target_ulong new_value);
489 typedef RISCVException (*riscv_csr_op_fn)(CPURISCVState *env, int csrno,
490                                           target_ulong *ret_value,
491                                           target_ulong new_value,
492                                           target_ulong write_mask);
493 
494 typedef struct {
495     const char *name;
496     riscv_csr_predicate_fn predicate;
497     riscv_csr_read_fn read;
498     riscv_csr_write_fn write;
499     riscv_csr_op_fn op;
500 } riscv_csr_operations;
501 
502 /* CSR function table constants */
503 enum {
504     CSR_TABLE_SIZE = 0x1000
505 };
506 
507 /* CSR function table */
508 extern riscv_csr_operations csr_ops[CSR_TABLE_SIZE];
509 
510 void riscv_get_csr_ops(int csrno, riscv_csr_operations *ops);
511 void riscv_set_csr_ops(int csrno, riscv_csr_operations *ops);
512 
513 void riscv_cpu_register_gdb_regs_for_features(CPUState *cs);
514 
515 #endif /* RISCV_CPU_H */
516