xref: /openbmc/qemu/target/riscv/cpu.h (revision 2582a95c)
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 #if defined(TARGET_RISCV32)
58 #define RVXLEN RV32
59 #elif defined(TARGET_RISCV64)
60 #define RVXLEN RV64
61 #endif
62 
63 #define RV(x) ((target_ulong)1 << (x - 'A'))
64 
65 #define RVI RV('I')
66 #define RVE RV('E') /* E and I are mutually exclusive */
67 #define RVM RV('M')
68 #define RVA RV('A')
69 #define RVF RV('F')
70 #define RVD RV('D')
71 #define RVV RV('V')
72 #define RVC RV('C')
73 #define RVS RV('S')
74 #define RVU RV('U')
75 #define RVH RV('H')
76 
77 /* S extension denotes that Supervisor mode exists, however it is possible
78    to have a core that support S mode but does not have an MMU and there
79    is currently no bit in misa to indicate whether an MMU exists or not
80    so a cpu features bitfield is required, likewise for optional PMP support */
81 enum {
82     RISCV_FEATURE_MMU,
83     RISCV_FEATURE_PMP,
84     RISCV_FEATURE_EPMP,
85     RISCV_FEATURE_MISA
86 };
87 
88 #define PRIV_VERSION_1_10_0 0x00011000
89 #define PRIV_VERSION_1_11_0 0x00011100
90 
91 #define VEXT_VERSION_0_07_1 0x00000701
92 
93 enum {
94     TRANSLATE_SUCCESS,
95     TRANSLATE_FAIL,
96     TRANSLATE_PMP_FAIL,
97     TRANSLATE_G_STAGE_FAIL
98 };
99 
100 #define MMU_USER_IDX 3
101 
102 #define MAX_RISCV_PMPS (16)
103 
104 typedef struct CPURISCVState CPURISCVState;
105 
106 #include "pmp.h"
107 
108 #define RV_VLEN_MAX 256
109 
110 FIELD(VTYPE, VLMUL, 0, 2)
111 FIELD(VTYPE, VSEW, 2, 3)
112 FIELD(VTYPE, VEDIV, 5, 2)
113 FIELD(VTYPE, RESERVED, 7, sizeof(target_ulong) * 8 - 9)
114 FIELD(VTYPE, VILL, sizeof(target_ulong) * 8 - 1, 1)
115 
116 struct CPURISCVState {
117     target_ulong gpr[32];
118     uint64_t fpr[32]; /* assume both F and D extensions */
119 
120     /* vector coprocessor state. */
121     uint64_t vreg[32 * RV_VLEN_MAX / 64] QEMU_ALIGNED(16);
122     target_ulong vxrm;
123     target_ulong vxsat;
124     target_ulong vl;
125     target_ulong vstart;
126     target_ulong vtype;
127 
128     target_ulong pc;
129     target_ulong load_res;
130     target_ulong load_val;
131 
132     target_ulong frm;
133 
134     target_ulong badaddr;
135     target_ulong guest_phys_fault_addr;
136 
137     target_ulong priv_ver;
138     target_ulong vext_ver;
139     target_ulong misa;
140     target_ulong misa_mask;
141 
142     uint32_t features;
143 
144 #ifdef CONFIG_USER_ONLY
145     uint32_t elf_flags;
146 #endif
147 
148 #ifndef CONFIG_USER_ONLY
149     target_ulong priv;
150     /* This contains QEMU specific information about the virt state. */
151     target_ulong virt;
152     target_ulong resetvec;
153 
154     target_ulong mhartid;
155     /*
156      * For RV32 this is 32-bit mstatus and 32-bit mstatush.
157      * For RV64 this is a 64-bit mstatus.
158      */
159     uint64_t mstatus;
160 
161     target_ulong mip;
162 
163     uint32_t miclaim;
164 
165     target_ulong mie;
166     target_ulong mideleg;
167 
168     target_ulong satp;   /* since: priv-1.10.0 */
169     target_ulong stval;
170     target_ulong medeleg;
171 
172     target_ulong stvec;
173     target_ulong sepc;
174     target_ulong scause;
175 
176     target_ulong mtvec;
177     target_ulong mepc;
178     target_ulong mcause;
179     target_ulong mtval;  /* since: priv-1.10.0 */
180 
181     /* Hypervisor CSRs */
182     target_ulong hstatus;
183     target_ulong hedeleg;
184     target_ulong hideleg;
185     target_ulong hcounteren;
186     target_ulong htval;
187     target_ulong htinst;
188     target_ulong hgatp;
189     uint64_t htimedelta;
190 
191     /* Virtual CSRs */
192     /*
193      * For RV32 this is 32-bit vsstatus and 32-bit vsstatush.
194      * For RV64 this is a 64-bit vsstatus.
195      */
196     uint64_t vsstatus;
197     target_ulong vstvec;
198     target_ulong vsscratch;
199     target_ulong vsepc;
200     target_ulong vscause;
201     target_ulong vstval;
202     target_ulong vsatp;
203 
204     target_ulong mtval2;
205     target_ulong mtinst;
206 
207     /* HS Backup CSRs */
208     target_ulong stvec_hs;
209     target_ulong sscratch_hs;
210     target_ulong sepc_hs;
211     target_ulong scause_hs;
212     target_ulong stval_hs;
213     target_ulong satp_hs;
214     uint64_t mstatus_hs;
215 
216     /* Signals whether the current exception occurred with two-stage address
217        translation active. */
218     bool two_stage_lookup;
219 
220     target_ulong scounteren;
221     target_ulong mcounteren;
222 
223     target_ulong sscratch;
224     target_ulong mscratch;
225 
226     /* temporary htif regs */
227     uint64_t mfromhost;
228     uint64_t mtohost;
229     uint64_t timecmp;
230 
231     /* physical memory protection */
232     pmp_table_t pmp_state;
233     target_ulong mseccfg;
234 
235     /* machine specific rdtime callback */
236     uint64_t (*rdtime_fn)(uint32_t);
237     uint32_t rdtime_fn_arg;
238 
239     /* True if in debugger mode.  */
240     bool debugger;
241 #endif
242 
243     float_status fp_status;
244 
245     /* Fields from here on are preserved across CPU reset. */
246     QEMUTimer *timer; /* Internal timer */
247 };
248 
249 OBJECT_DECLARE_TYPE(RISCVCPU, RISCVCPUClass,
250                     RISCV_CPU)
251 
252 /**
253  * RISCVCPUClass:
254  * @parent_realize: The parent class' realize handler.
255  * @parent_reset: The parent class' reset handler.
256  *
257  * A RISCV CPU model.
258  */
259 struct RISCVCPUClass {
260     /*< private >*/
261     CPUClass parent_class;
262     /*< public >*/
263     DeviceRealize parent_realize;
264     DeviceReset parent_reset;
265 };
266 
267 /**
268  * RISCVCPU:
269  * @env: #CPURISCVState
270  *
271  * A RISCV CPU.
272  */
273 struct RISCVCPU {
274     /*< private >*/
275     CPUState parent_obj;
276     /*< public >*/
277     CPUNegativeOffsetState neg;
278     CPURISCVState env;
279 
280     char *dyn_csr_xml;
281 
282     /* Configuration Settings */
283     struct {
284         bool ext_i;
285         bool ext_e;
286         bool ext_g;
287         bool ext_m;
288         bool ext_a;
289         bool ext_f;
290         bool ext_d;
291         bool ext_c;
292         bool ext_s;
293         bool ext_u;
294         bool ext_h;
295         bool ext_v;
296         bool ext_counters;
297         bool ext_ifencei;
298         bool ext_icsr;
299 
300         char *priv_spec;
301         char *user_spec;
302         char *vext_spec;
303         uint16_t vlen;
304         uint16_t elen;
305         bool mmu;
306         bool pmp;
307         uint64_t resetvec;
308     } cfg;
309 };
310 
311 static inline int riscv_has_ext(CPURISCVState *env, target_ulong ext)
312 {
313     return (env->misa & ext) != 0;
314 }
315 
316 static inline bool riscv_feature(CPURISCVState *env, int feature)
317 {
318     return env->features & (1ULL << feature);
319 }
320 
321 #include "cpu_user.h"
322 #include "cpu_bits.h"
323 
324 extern const char * const riscv_int_regnames[];
325 extern const char * const riscv_fpr_regnames[];
326 extern const char * const riscv_excp_names[];
327 extern const char * const riscv_intr_names[];
328 
329 const char *riscv_cpu_get_trap_name(target_ulong cause, bool async);
330 void riscv_cpu_do_interrupt(CPUState *cpu);
331 int riscv_cpu_write_elf64_note(WriteCoreDumpFunction f, CPUState *cs,
332                                int cpuid, void *opaque);
333 int riscv_cpu_write_elf32_note(WriteCoreDumpFunction f, CPUState *cs,
334                                int cpuid, void *opaque);
335 int riscv_cpu_gdb_read_register(CPUState *cpu, GByteArray *buf, int reg);
336 int riscv_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);
337 bool riscv_cpu_exec_interrupt(CPUState *cs, int interrupt_request);
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);
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_signal_handler riscv_cpu_signal_handler
361 #define cpu_list riscv_cpu_list
362 #define cpu_mmu_index riscv_cpu_mmu_index
363 
364 #ifndef CONFIG_USER_ONLY
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 int riscv_cpu_signal_handler(int host_signum, void *pinfo, void *puc);
376 void QEMU_NORETURN riscv_raise_exception(CPURISCVState *env,
377                                          uint32_t exception, uintptr_t pc);
378 
379 target_ulong riscv_cpu_get_fflags(CPURISCVState *env);
380 void riscv_cpu_set_fflags(CPURISCVState *env, target_ulong);
381 
382 #define TB_FLAGS_MMU_MASK   7
383 #define TB_FLAGS_PRIV_MMU_MASK                3
384 #define TB_FLAGS_PRIV_HYP_ACCESS_MASK   (1 << 2)
385 #define TB_FLAGS_MSTATUS_FS MSTATUS_FS
386 
387 typedef CPURISCVState CPUArchState;
388 typedef RISCVCPU ArchCPU;
389 #include "exec/cpu-all.h"
390 
391 FIELD(TB_FLAGS, VL_EQ_VLMAX, 2, 1)
392 FIELD(TB_FLAGS, LMUL, 3, 2)
393 FIELD(TB_FLAGS, SEW, 5, 3)
394 FIELD(TB_FLAGS, VILL, 8, 1)
395 /* Is a Hypervisor instruction load/store allowed? */
396 FIELD(TB_FLAGS, HLSX, 9, 1)
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 #endif
455 
456     *pflags = flags;
457 }
458 
459 RISCVException riscv_csrrw(CPURISCVState *env, int csrno,
460                            target_ulong *ret_value,
461                            target_ulong new_value, target_ulong write_mask);
462 RISCVException riscv_csrrw_debug(CPURISCVState *env, int csrno,
463                                  target_ulong *ret_value,
464                                  target_ulong new_value,
465                                  target_ulong write_mask);
466 
467 static inline void riscv_csr_write(CPURISCVState *env, int csrno,
468                                    target_ulong val)
469 {
470     riscv_csrrw(env, csrno, NULL, val, MAKE_64BIT_MASK(0, TARGET_LONG_BITS));
471 }
472 
473 static inline target_ulong riscv_csr_read(CPURISCVState *env, int csrno)
474 {
475     target_ulong val = 0;
476     riscv_csrrw(env, csrno, &val, 0, 0);
477     return val;
478 }
479 
480 typedef RISCVException (*riscv_csr_predicate_fn)(CPURISCVState *env,
481                                                  int csrno);
482 typedef RISCVException (*riscv_csr_read_fn)(CPURISCVState *env, int csrno,
483                                             target_ulong *ret_value);
484 typedef RISCVException (*riscv_csr_write_fn)(CPURISCVState *env, int csrno,
485                                              target_ulong new_value);
486 typedef RISCVException (*riscv_csr_op_fn)(CPURISCVState *env, int csrno,
487                                           target_ulong *ret_value,
488                                           target_ulong new_value,
489                                           target_ulong write_mask);
490 
491 typedef struct {
492     const char *name;
493     riscv_csr_predicate_fn predicate;
494     riscv_csr_read_fn read;
495     riscv_csr_write_fn write;
496     riscv_csr_op_fn op;
497 } riscv_csr_operations;
498 
499 /* CSR function table constants */
500 enum {
501     CSR_TABLE_SIZE = 0x1000
502 };
503 
504 /* CSR function table */
505 extern riscv_csr_operations csr_ops[CSR_TABLE_SIZE];
506 
507 void riscv_get_csr_ops(int csrno, riscv_csr_operations *ops);
508 void riscv_set_csr_ops(int csrno, riscv_csr_operations *ops);
509 
510 void riscv_cpu_register_gdb_regs_for_features(CPUState *cs);
511 
512 #endif /* RISCV_CPU_H */
513