xref: /openbmc/qemu/target/riscv/cpu.h (revision cd032fe7)
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 #include "qemu/int128.h"
29 #include "cpu_bits.h"
30 
31 #define TCG_GUEST_DEFAULT_MO 0
32 
33 #define TYPE_RISCV_CPU "riscv-cpu"
34 
35 #define RISCV_CPU_TYPE_SUFFIX "-" TYPE_RISCV_CPU
36 #define RISCV_CPU_TYPE_NAME(name) (name RISCV_CPU_TYPE_SUFFIX)
37 #define CPU_RESOLVING_TYPE TYPE_RISCV_CPU
38 
39 #define TYPE_RISCV_CPU_ANY              RISCV_CPU_TYPE_NAME("any")
40 #define TYPE_RISCV_CPU_BASE32           RISCV_CPU_TYPE_NAME("rv32")
41 #define TYPE_RISCV_CPU_BASE64           RISCV_CPU_TYPE_NAME("rv64")
42 #define TYPE_RISCV_CPU_BASE128          RISCV_CPU_TYPE_NAME("x-rv128")
43 #define TYPE_RISCV_CPU_IBEX             RISCV_CPU_TYPE_NAME("lowrisc-ibex")
44 #define TYPE_RISCV_CPU_SHAKTI_C         RISCV_CPU_TYPE_NAME("shakti-c")
45 #define TYPE_RISCV_CPU_SIFIVE_E31       RISCV_CPU_TYPE_NAME("sifive-e31")
46 #define TYPE_RISCV_CPU_SIFIVE_E34       RISCV_CPU_TYPE_NAME("sifive-e34")
47 #define TYPE_RISCV_CPU_SIFIVE_E51       RISCV_CPU_TYPE_NAME("sifive-e51")
48 #define TYPE_RISCV_CPU_SIFIVE_U34       RISCV_CPU_TYPE_NAME("sifive-u34")
49 #define TYPE_RISCV_CPU_SIFIVE_U54       RISCV_CPU_TYPE_NAME("sifive-u54")
50 #define TYPE_RISCV_CPU_HOST             RISCV_CPU_TYPE_NAME("host")
51 
52 #if defined(TARGET_RISCV32)
53 # define TYPE_RISCV_CPU_BASE            TYPE_RISCV_CPU_BASE32
54 #elif defined(TARGET_RISCV64)
55 # define TYPE_RISCV_CPU_BASE            TYPE_RISCV_CPU_BASE64
56 #endif
57 
58 #define RV(x) ((target_ulong)1 << (x - 'A'))
59 
60 #define RVI RV('I')
61 #define RVE RV('E') /* E and I are mutually exclusive */
62 #define RVM RV('M')
63 #define RVA RV('A')
64 #define RVF RV('F')
65 #define RVD RV('D')
66 #define RVV RV('V')
67 #define RVC RV('C')
68 #define RVS RV('S')
69 #define RVU RV('U')
70 #define RVH RV('H')
71 #define RVJ RV('J')
72 
73 /* S extension denotes that Supervisor mode exists, however it is possible
74    to have a core that support S mode but does not have an MMU and there
75    is currently no bit in misa to indicate whether an MMU exists or not
76    so a cpu features bitfield is required, likewise for optional PMP support */
77 enum {
78     RISCV_FEATURE_MMU,
79     RISCV_FEATURE_PMP,
80     RISCV_FEATURE_EPMP,
81     RISCV_FEATURE_MISA
82 };
83 
84 #define PRIV_VERSION_1_10_0 0x00011000
85 #define PRIV_VERSION_1_11_0 0x00011100
86 
87 #define VEXT_VERSION_1_00_0 0x00010000
88 
89 enum {
90     TRANSLATE_SUCCESS,
91     TRANSLATE_FAIL,
92     TRANSLATE_PMP_FAIL,
93     TRANSLATE_G_STAGE_FAIL
94 };
95 
96 #define MMU_USER_IDX 3
97 
98 #define MAX_RISCV_PMPS (16)
99 
100 typedef struct CPURISCVState CPURISCVState;
101 
102 #if !defined(CONFIG_USER_ONLY)
103 #include "pmp.h"
104 #endif
105 
106 #define RV_VLEN_MAX 1024
107 
108 FIELD(VTYPE, VLMUL, 0, 3)
109 FIELD(VTYPE, VSEW, 3, 3)
110 FIELD(VTYPE, VTA, 6, 1)
111 FIELD(VTYPE, VMA, 7, 1)
112 FIELD(VTYPE, VEDIV, 8, 2)
113 FIELD(VTYPE, RESERVED, 10, sizeof(target_ulong) * 8 - 11)
114 
115 struct CPURISCVState {
116     target_ulong gpr[32];
117     target_ulong gprh[32]; /* 64 top bits of the 128-bit registers */
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     bool vill;
128 
129     target_ulong pc;
130     target_ulong load_res;
131     target_ulong load_val;
132 
133     target_ulong frm;
134 
135     target_ulong badaddr;
136     uint32_t bins;
137 
138     target_ulong guest_phys_fault_addr;
139 
140     target_ulong priv_ver;
141     target_ulong bext_ver;
142     target_ulong vext_ver;
143 
144     /* RISCVMXL, but uint32_t for vmstate migration */
145     uint32_t misa_mxl;      /* current mxl */
146     uint32_t misa_mxl_max;  /* max mxl for this cpu */
147     uint32_t misa_ext;      /* current extensions */
148     uint32_t misa_ext_mask; /* max ext for this cpu */
149     uint32_t xl;            /* current xlen */
150 
151     /* 128-bit helpers upper part return value */
152     target_ulong retxh;
153 
154     uint32_t features;
155 
156 #ifdef CONFIG_USER_ONLY
157     uint32_t elf_flags;
158 #endif
159 
160 #ifndef CONFIG_USER_ONLY
161     target_ulong priv;
162     /* This contains QEMU specific information about the virt state. */
163     target_ulong virt;
164     target_ulong geilen;
165     target_ulong resetvec;
166 
167     target_ulong mhartid;
168     /*
169      * For RV32 this is 32-bit mstatus and 32-bit mstatush.
170      * For RV64 this is a 64-bit mstatus.
171      */
172     uint64_t mstatus;
173 
174     target_ulong mip;
175 
176     uint32_t miclaim;
177 
178     target_ulong mie;
179     target_ulong mideleg;
180 
181     target_ulong satp;   /* since: priv-1.10.0 */
182     target_ulong stval;
183     target_ulong medeleg;
184 
185     target_ulong stvec;
186     target_ulong sepc;
187     target_ulong scause;
188 
189     target_ulong mtvec;
190     target_ulong mepc;
191     target_ulong mcause;
192     target_ulong mtval;  /* since: priv-1.10.0 */
193 
194     /* Hypervisor CSRs */
195     target_ulong hstatus;
196     target_ulong hedeleg;
197     target_ulong hideleg;
198     target_ulong hcounteren;
199     target_ulong htval;
200     target_ulong htinst;
201     target_ulong hgatp;
202     target_ulong hgeie;
203     target_ulong hgeip;
204     uint64_t htimedelta;
205 
206     /* Upper 64-bits of 128-bit CSRs */
207     uint64_t mscratchh;
208     uint64_t sscratchh;
209 
210     /* Virtual CSRs */
211     /*
212      * For RV32 this is 32-bit vsstatus and 32-bit vsstatush.
213      * For RV64 this is a 64-bit vsstatus.
214      */
215     uint64_t vsstatus;
216     target_ulong vstvec;
217     target_ulong vsscratch;
218     target_ulong vsepc;
219     target_ulong vscause;
220     target_ulong vstval;
221     target_ulong vsatp;
222 
223     target_ulong mtval2;
224     target_ulong mtinst;
225 
226     /* HS Backup CSRs */
227     target_ulong stvec_hs;
228     target_ulong sscratch_hs;
229     target_ulong sepc_hs;
230     target_ulong scause_hs;
231     target_ulong stval_hs;
232     target_ulong satp_hs;
233     uint64_t mstatus_hs;
234 
235     /* Signals whether the current exception occurred with two-stage address
236        translation active. */
237     bool two_stage_lookup;
238 
239     target_ulong scounteren;
240     target_ulong mcounteren;
241 
242     target_ulong sscratch;
243     target_ulong mscratch;
244 
245     /* temporary htif regs */
246     uint64_t mfromhost;
247     uint64_t mtohost;
248     uint64_t timecmp;
249 
250     /* physical memory protection */
251     pmp_table_t pmp_state;
252     target_ulong mseccfg;
253 
254     /* machine specific rdtime callback */
255     uint64_t (*rdtime_fn)(uint32_t);
256     uint32_t rdtime_fn_arg;
257 
258     /* True if in debugger mode.  */
259     bool debugger;
260 
261     /*
262      * CSRs for PointerMasking extension
263      */
264     target_ulong mmte;
265     target_ulong mpmmask;
266     target_ulong mpmbase;
267     target_ulong spmmask;
268     target_ulong spmbase;
269     target_ulong upmmask;
270     target_ulong upmbase;
271 #endif
272     target_ulong cur_pmmask;
273     target_ulong cur_pmbase;
274 
275     float_status fp_status;
276 
277     /* Fields from here on are preserved across CPU reset. */
278     QEMUTimer *timer; /* Internal timer */
279 
280     hwaddr kernel_addr;
281     hwaddr fdt_addr;
282 
283     /* kvm timer */
284     bool kvm_timer_dirty;
285     uint64_t kvm_timer_time;
286     uint64_t kvm_timer_compare;
287     uint64_t kvm_timer_state;
288     uint64_t kvm_timer_frequency;
289 };
290 
291 OBJECT_DECLARE_TYPE(RISCVCPU, RISCVCPUClass,
292                     RISCV_CPU)
293 
294 /**
295  * RISCVCPUClass:
296  * @parent_realize: The parent class' realize handler.
297  * @parent_reset: The parent class' reset handler.
298  *
299  * A RISCV CPU model.
300  */
301 struct RISCVCPUClass {
302     /*< private >*/
303     CPUClass parent_class;
304     /*< public >*/
305     DeviceRealize parent_realize;
306     DeviceReset parent_reset;
307 };
308 
309 struct RISCVCPUConfig {
310     bool ext_i;
311     bool ext_e;
312     bool ext_g;
313     bool ext_m;
314     bool ext_a;
315     bool ext_f;
316     bool ext_d;
317     bool ext_c;
318     bool ext_s;
319     bool ext_u;
320     bool ext_h;
321     bool ext_j;
322     bool ext_v;
323     bool ext_zba;
324     bool ext_zbb;
325     bool ext_zbc;
326     bool ext_zbs;
327     bool ext_counters;
328     bool ext_ifencei;
329     bool ext_icsr;
330     bool ext_zfh;
331     bool ext_zfhmin;
332     bool ext_zve32f;
333     bool ext_zve64f;
334 
335     /* Vendor-specific custom extensions */
336     bool ext_XVentanaCondOps;
337 
338     char *priv_spec;
339     char *user_spec;
340     char *bext_spec;
341     char *vext_spec;
342     uint16_t vlen;
343     uint16_t elen;
344     bool mmu;
345     bool pmp;
346     bool epmp;
347     uint64_t resetvec;
348 };
349 
350 typedef struct RISCVCPUConfig RISCVCPUConfig;
351 
352 /**
353  * RISCVCPU:
354  * @env: #CPURISCVState
355  *
356  * A RISCV CPU.
357  */
358 struct RISCVCPU {
359     /*< private >*/
360     CPUState parent_obj;
361     /*< public >*/
362     CPUNegativeOffsetState neg;
363     CPURISCVState env;
364 
365     char *dyn_csr_xml;
366     char *dyn_vreg_xml;
367 
368     /* Configuration Settings */
369     RISCVCPUConfig cfg;
370 };
371 
372 static inline int riscv_has_ext(CPURISCVState *env, target_ulong ext)
373 {
374     return (env->misa_ext & ext) != 0;
375 }
376 
377 static inline bool riscv_feature(CPURISCVState *env, int feature)
378 {
379     return env->features & (1ULL << feature);
380 }
381 
382 #include "cpu_user.h"
383 
384 extern const char * const riscv_int_regnames[];
385 extern const char * const riscv_int_regnamesh[];
386 extern const char * const riscv_fpr_regnames[];
387 
388 const char *riscv_cpu_get_trap_name(target_ulong cause, bool async);
389 void riscv_cpu_do_interrupt(CPUState *cpu);
390 int riscv_cpu_write_elf64_note(WriteCoreDumpFunction f, CPUState *cs,
391                                int cpuid, void *opaque);
392 int riscv_cpu_write_elf32_note(WriteCoreDumpFunction f, CPUState *cs,
393                                int cpuid, void *opaque);
394 int riscv_cpu_gdb_read_register(CPUState *cpu, GByteArray *buf, int reg);
395 int riscv_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);
396 bool riscv_cpu_fp_enabled(CPURISCVState *env);
397 target_ulong riscv_cpu_get_geilen(CPURISCVState *env);
398 void riscv_cpu_set_geilen(CPURISCVState *env, target_ulong geilen);
399 bool riscv_cpu_vector_enabled(CPURISCVState *env);
400 bool riscv_cpu_virt_enabled(CPURISCVState *env);
401 void riscv_cpu_set_virt_enabled(CPURISCVState *env, bool enable);
402 bool riscv_cpu_two_stage_lookup(int mmu_idx);
403 int riscv_cpu_mmu_index(CPURISCVState *env, bool ifetch);
404 hwaddr riscv_cpu_get_phys_page_debug(CPUState *cpu, vaddr addr);
405 void  riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
406                                     MMUAccessType access_type, int mmu_idx,
407                                     uintptr_t retaddr) QEMU_NORETURN;
408 bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
409                         MMUAccessType access_type, int mmu_idx,
410                         bool probe, uintptr_t retaddr);
411 void riscv_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr,
412                                      vaddr addr, unsigned size,
413                                      MMUAccessType access_type,
414                                      int mmu_idx, MemTxAttrs attrs,
415                                      MemTxResult response, uintptr_t retaddr);
416 char *riscv_isa_string(RISCVCPU *cpu);
417 void riscv_cpu_list(void);
418 
419 #define cpu_list riscv_cpu_list
420 #define cpu_mmu_index riscv_cpu_mmu_index
421 
422 #ifndef CONFIG_USER_ONLY
423 bool riscv_cpu_exec_interrupt(CPUState *cs, int interrupt_request);
424 void riscv_cpu_swap_hypervisor_regs(CPURISCVState *env);
425 int riscv_cpu_claim_interrupts(RISCVCPU *cpu, uint32_t interrupts);
426 uint32_t riscv_cpu_update_mip(RISCVCPU *cpu, uint32_t mask, uint32_t value);
427 #define BOOL_TO_MASK(x) (-!!(x)) /* helper for riscv_cpu_update_mip value */
428 void riscv_cpu_set_rdtime_fn(CPURISCVState *env, uint64_t (*fn)(uint32_t),
429                              uint32_t arg);
430 #endif
431 void riscv_cpu_set_mode(CPURISCVState *env, target_ulong newpriv);
432 
433 void riscv_translate_init(void);
434 void QEMU_NORETURN riscv_raise_exception(CPURISCVState *env,
435                                          uint32_t exception, uintptr_t pc);
436 
437 target_ulong riscv_cpu_get_fflags(CPURISCVState *env);
438 void riscv_cpu_set_fflags(CPURISCVState *env, target_ulong);
439 
440 #define TB_FLAGS_PRIV_MMU_MASK                3
441 #define TB_FLAGS_PRIV_HYP_ACCESS_MASK   (1 << 2)
442 #define TB_FLAGS_MSTATUS_FS MSTATUS_FS
443 #define TB_FLAGS_MSTATUS_VS MSTATUS_VS
444 
445 typedef CPURISCVState CPUArchState;
446 typedef RISCVCPU ArchCPU;
447 #include "exec/cpu-all.h"
448 
449 FIELD(TB_FLAGS, MEM_IDX, 0, 3)
450 FIELD(TB_FLAGS, LMUL, 3, 3)
451 FIELD(TB_FLAGS, SEW, 6, 3)
452 /* Skip MSTATUS_VS (0x600) bits */
453 FIELD(TB_FLAGS, VL_EQ_VLMAX, 11, 1)
454 FIELD(TB_FLAGS, VILL, 12, 1)
455 /* Skip MSTATUS_FS (0x6000) bits */
456 /* Is a Hypervisor instruction load/store allowed? */
457 FIELD(TB_FLAGS, HLSX, 15, 1)
458 FIELD(TB_FLAGS, MSTATUS_HS_FS, 16, 2)
459 FIELD(TB_FLAGS, MSTATUS_HS_VS, 18, 2)
460 /* The combination of MXL/SXL/UXL that applies to the current cpu mode. */
461 FIELD(TB_FLAGS, XL, 20, 2)
462 /* If PointerMasking should be applied */
463 FIELD(TB_FLAGS, PM_MASK_ENABLED, 22, 1)
464 FIELD(TB_FLAGS, PM_BASE_ENABLED, 23, 1)
465 
466 #ifdef TARGET_RISCV32
467 #define riscv_cpu_mxl(env)  ((void)(env), MXL_RV32)
468 #else
469 static inline RISCVMXL riscv_cpu_mxl(CPURISCVState *env)
470 {
471     return env->misa_mxl;
472 }
473 #endif
474 
475 #if defined(TARGET_RISCV32)
476 #define cpu_recompute_xl(env)  ((void)(env), MXL_RV32)
477 #else
478 static inline RISCVMXL cpu_recompute_xl(CPURISCVState *env)
479 {
480     RISCVMXL xl = env->misa_mxl;
481 #if !defined(CONFIG_USER_ONLY)
482     /*
483      * When emulating a 32-bit-only cpu, use RV32.
484      * When emulating a 64-bit cpu, and MXL has been reduced to RV32,
485      * MSTATUSH doesn't have UXL/SXL, therefore XLEN cannot be widened
486      * back to RV64 for lower privs.
487      */
488     if (xl != MXL_RV32) {
489         switch (env->priv) {
490         case PRV_M:
491             break;
492         case PRV_U:
493             xl = get_field(env->mstatus, MSTATUS64_UXL);
494             break;
495         default: /* PRV_S | PRV_H */
496             xl = get_field(env->mstatus, MSTATUS64_SXL);
497             break;
498         }
499     }
500 #endif
501     return xl;
502 }
503 #endif
504 
505 static inline int riscv_cpu_xlen(CPURISCVState *env)
506 {
507     return 16 << env->xl;
508 }
509 
510 /*
511  * Encode LMUL to lmul as follows:
512  *     LMUL    vlmul    lmul
513  *      1       000       0
514  *      2       001       1
515  *      4       010       2
516  *      8       011       3
517  *      -       100       -
518  *     1/8      101      -3
519  *     1/4      110      -2
520  *     1/2      111      -1
521  *
522  * then, we can calculate VLMAX = vlen >> (vsew + 3 - lmul)
523  * e.g. vlen = 256 bits, SEW = 16, LMUL = 1/8
524  *      => VLMAX = vlen >> (1 + 3 - (-3))
525  *               = 256 >> 7
526  *               = 2
527  */
528 static inline uint32_t vext_get_vlmax(RISCVCPU *cpu, target_ulong vtype)
529 {
530     uint8_t sew = FIELD_EX64(vtype, VTYPE, VSEW);
531     int8_t lmul = sextract32(FIELD_EX64(vtype, VTYPE, VLMUL), 0, 3);
532     return cpu->cfg.vlen >> (sew + 3 - lmul);
533 }
534 
535 void cpu_get_tb_cpu_state(CPURISCVState *env, target_ulong *pc,
536                           target_ulong *cs_base, uint32_t *pflags);
537 
538 void riscv_cpu_update_mask(CPURISCVState *env);
539 
540 RISCVException riscv_csrrw(CPURISCVState *env, int csrno,
541                            target_ulong *ret_value,
542                            target_ulong new_value, target_ulong write_mask);
543 RISCVException riscv_csrrw_debug(CPURISCVState *env, int csrno,
544                                  target_ulong *ret_value,
545                                  target_ulong new_value,
546                                  target_ulong write_mask);
547 
548 static inline void riscv_csr_write(CPURISCVState *env, int csrno,
549                                    target_ulong val)
550 {
551     riscv_csrrw(env, csrno, NULL, val, MAKE_64BIT_MASK(0, TARGET_LONG_BITS));
552 }
553 
554 static inline target_ulong riscv_csr_read(CPURISCVState *env, int csrno)
555 {
556     target_ulong val = 0;
557     riscv_csrrw(env, csrno, &val, 0, 0);
558     return val;
559 }
560 
561 typedef RISCVException (*riscv_csr_predicate_fn)(CPURISCVState *env,
562                                                  int csrno);
563 typedef RISCVException (*riscv_csr_read_fn)(CPURISCVState *env, int csrno,
564                                             target_ulong *ret_value);
565 typedef RISCVException (*riscv_csr_write_fn)(CPURISCVState *env, int csrno,
566                                              target_ulong new_value);
567 typedef RISCVException (*riscv_csr_op_fn)(CPURISCVState *env, int csrno,
568                                           target_ulong *ret_value,
569                                           target_ulong new_value,
570                                           target_ulong write_mask);
571 
572 RISCVException riscv_csrrw_i128(CPURISCVState *env, int csrno,
573                                 Int128 *ret_value,
574                                 Int128 new_value, Int128 write_mask);
575 
576 typedef RISCVException (*riscv_csr_read128_fn)(CPURISCVState *env, int csrno,
577                                                Int128 *ret_value);
578 typedef RISCVException (*riscv_csr_write128_fn)(CPURISCVState *env, int csrno,
579                                              Int128 new_value);
580 
581 typedef struct {
582     const char *name;
583     riscv_csr_predicate_fn predicate;
584     riscv_csr_read_fn read;
585     riscv_csr_write_fn write;
586     riscv_csr_op_fn op;
587     riscv_csr_read128_fn read128;
588     riscv_csr_write128_fn write128;
589 } riscv_csr_operations;
590 
591 /* CSR function table constants */
592 enum {
593     CSR_TABLE_SIZE = 0x1000
594 };
595 
596 /* CSR function table */
597 extern riscv_csr_operations csr_ops[CSR_TABLE_SIZE];
598 
599 void riscv_get_csr_ops(int csrno, riscv_csr_operations *ops);
600 void riscv_set_csr_ops(int csrno, riscv_csr_operations *ops);
601 
602 void riscv_cpu_register_gdb_regs_for_features(CPUState *cs);
603 
604 #endif /* RISCV_CPU_H */
605