xref: /openbmc/qemu/target/riscv/cpu.h (revision 075eeda9)
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 "qemu/cpu-float.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     RISCV_FEATURE_AIA,
83     RISCV_FEATURE_DEBUG
84 };
85 
86 /* Privileged specification version */
87 enum {
88     PRIV_VERSION_1_10_0 = 0,
89     PRIV_VERSION_1_11_0,
90     PRIV_VERSION_1_12_0,
91 };
92 
93 #define VEXT_VERSION_1_00_0 0x00010000
94 
95 enum {
96     TRANSLATE_SUCCESS,
97     TRANSLATE_FAIL,
98     TRANSLATE_PMP_FAIL,
99     TRANSLATE_G_STAGE_FAIL
100 };
101 
102 #define MMU_USER_IDX 3
103 
104 #define MAX_RISCV_PMPS (16)
105 
106 typedef struct CPUArchState CPURISCVState;
107 
108 #if !defined(CONFIG_USER_ONLY)
109 #include "pmp.h"
110 #include "debug.h"
111 #endif
112 
113 #define RV_VLEN_MAX 1024
114 
115 FIELD(VTYPE, VLMUL, 0, 3)
116 FIELD(VTYPE, VSEW, 3, 3)
117 FIELD(VTYPE, VTA, 6, 1)
118 FIELD(VTYPE, VMA, 7, 1)
119 FIELD(VTYPE, VEDIV, 8, 2)
120 FIELD(VTYPE, RESERVED, 10, sizeof(target_ulong) * 8 - 11)
121 
122 struct CPUArchState {
123     target_ulong gpr[32];
124     target_ulong gprh[32]; /* 64 top bits of the 128-bit registers */
125     uint64_t fpr[32]; /* assume both F and D extensions */
126 
127     /* vector coprocessor state. */
128     uint64_t vreg[32 * RV_VLEN_MAX / 64] QEMU_ALIGNED(16);
129     target_ulong vxrm;
130     target_ulong vxsat;
131     target_ulong vl;
132     target_ulong vstart;
133     target_ulong vtype;
134     bool vill;
135 
136     target_ulong pc;
137     target_ulong load_res;
138     target_ulong load_val;
139 
140     target_ulong frm;
141 
142     target_ulong badaddr;
143     uint32_t bins;
144 
145     target_ulong guest_phys_fault_addr;
146 
147     target_ulong priv_ver;
148     target_ulong bext_ver;
149     target_ulong vext_ver;
150 
151     /* RISCVMXL, but uint32_t for vmstate migration */
152     uint32_t misa_mxl;      /* current mxl */
153     uint32_t misa_mxl_max;  /* max mxl for this cpu */
154     uint32_t misa_ext;      /* current extensions */
155     uint32_t misa_ext_mask; /* max ext for this cpu */
156     uint32_t xl;            /* current xlen */
157 
158     /* 128-bit helpers upper part return value */
159     target_ulong retxh;
160 
161     uint32_t features;
162 
163 #ifdef CONFIG_USER_ONLY
164     uint32_t elf_flags;
165 #endif
166 
167 #ifndef CONFIG_USER_ONLY
168     target_ulong priv;
169     /* This contains QEMU specific information about the virt state. */
170     target_ulong virt;
171     target_ulong geilen;
172     target_ulong resetvec;
173 
174     target_ulong mhartid;
175     /*
176      * For RV32 this is 32-bit mstatus and 32-bit mstatush.
177      * For RV64 this is a 64-bit mstatus.
178      */
179     uint64_t mstatus;
180 
181     uint64_t mip;
182     /*
183      * MIP contains the software writable version of SEIP ORed with the
184      * external interrupt value. The MIP register is always up-to-date.
185      * To keep track of the current source, we also save booleans of the values
186      * here.
187      */
188     bool external_seip;
189     bool software_seip;
190 
191     uint64_t miclaim;
192 
193     uint64_t mie;
194     uint64_t mideleg;
195 
196     target_ulong satp;   /* since: priv-1.10.0 */
197     target_ulong stval;
198     target_ulong medeleg;
199 
200     target_ulong stvec;
201     target_ulong sepc;
202     target_ulong scause;
203 
204     target_ulong mtvec;
205     target_ulong mepc;
206     target_ulong mcause;
207     target_ulong mtval;  /* since: priv-1.10.0 */
208 
209     /* Machine and Supervisor interrupt priorities */
210     uint8_t miprio[64];
211     uint8_t siprio[64];
212 
213     /* AIA CSRs */
214     target_ulong miselect;
215     target_ulong siselect;
216 
217     /* Hypervisor CSRs */
218     target_ulong hstatus;
219     target_ulong hedeleg;
220     uint64_t hideleg;
221     target_ulong hcounteren;
222     target_ulong htval;
223     target_ulong htinst;
224     target_ulong hgatp;
225     target_ulong hgeie;
226     target_ulong hgeip;
227     uint64_t htimedelta;
228 
229     /* Hypervisor controlled virtual interrupt priorities */
230     target_ulong hvictl;
231     uint8_t hviprio[64];
232 
233     /* Upper 64-bits of 128-bit CSRs */
234     uint64_t mscratchh;
235     uint64_t sscratchh;
236 
237     /* Virtual CSRs */
238     /*
239      * For RV32 this is 32-bit vsstatus and 32-bit vsstatush.
240      * For RV64 this is a 64-bit vsstatus.
241      */
242     uint64_t vsstatus;
243     target_ulong vstvec;
244     target_ulong vsscratch;
245     target_ulong vsepc;
246     target_ulong vscause;
247     target_ulong vstval;
248     target_ulong vsatp;
249 
250     /* AIA VS-mode CSRs */
251     target_ulong vsiselect;
252 
253     target_ulong mtval2;
254     target_ulong mtinst;
255 
256     /* HS Backup CSRs */
257     target_ulong stvec_hs;
258     target_ulong sscratch_hs;
259     target_ulong sepc_hs;
260     target_ulong scause_hs;
261     target_ulong stval_hs;
262     target_ulong satp_hs;
263     uint64_t mstatus_hs;
264 
265     /* Signals whether the current exception occurred with two-stage address
266        translation active. */
267     bool two_stage_lookup;
268 
269     target_ulong scounteren;
270     target_ulong mcounteren;
271 
272     target_ulong sscratch;
273     target_ulong mscratch;
274 
275     /* temporary htif regs */
276     uint64_t mfromhost;
277     uint64_t mtohost;
278     uint64_t timecmp;
279 
280     /* physical memory protection */
281     pmp_table_t pmp_state;
282     target_ulong mseccfg;
283 
284     /* trigger module */
285     target_ulong trigger_cur;
286     type2_trigger_t type2_trig[TRIGGER_TYPE2_NUM];
287 
288     /* machine specific rdtime callback */
289     uint64_t (*rdtime_fn)(void *);
290     void *rdtime_fn_arg;
291 
292     /* machine specific AIA ireg read-modify-write callback */
293 #define AIA_MAKE_IREG(__isel, __priv, __virt, __vgein, __xlen) \
294     ((((__xlen) & 0xff) << 24) | \
295      (((__vgein) & 0x3f) << 20) | \
296      (((__virt) & 0x1) << 18) | \
297      (((__priv) & 0x3) << 16) | \
298      (__isel & 0xffff))
299 #define AIA_IREG_ISEL(__ireg)                  ((__ireg) & 0xffff)
300 #define AIA_IREG_PRIV(__ireg)                  (((__ireg) >> 16) & 0x3)
301 #define AIA_IREG_VIRT(__ireg)                  (((__ireg) >> 18) & 0x1)
302 #define AIA_IREG_VGEIN(__ireg)                 (((__ireg) >> 20) & 0x3f)
303 #define AIA_IREG_XLEN(__ireg)                  (((__ireg) >> 24) & 0xff)
304     int (*aia_ireg_rmw_fn[4])(void *arg, target_ulong reg,
305         target_ulong *val, target_ulong new_val, target_ulong write_mask);
306     void *aia_ireg_rmw_fn_arg[4];
307 
308     /* True if in debugger mode.  */
309     bool debugger;
310 
311     /*
312      * CSRs for PointerMasking extension
313      */
314     target_ulong mmte;
315     target_ulong mpmmask;
316     target_ulong mpmbase;
317     target_ulong spmmask;
318     target_ulong spmbase;
319     target_ulong upmmask;
320     target_ulong upmbase;
321 
322     /* CSRs for execution enviornment configuration */
323     uint64_t menvcfg;
324     target_ulong senvcfg;
325     uint64_t henvcfg;
326 #endif
327     target_ulong cur_pmmask;
328     target_ulong cur_pmbase;
329 
330     float_status fp_status;
331 
332     /* Fields from here on are preserved across CPU reset. */
333     QEMUTimer *timer; /* Internal timer */
334 
335     hwaddr kernel_addr;
336     hwaddr fdt_addr;
337 
338     /* kvm timer */
339     bool kvm_timer_dirty;
340     uint64_t kvm_timer_time;
341     uint64_t kvm_timer_compare;
342     uint64_t kvm_timer_state;
343     uint64_t kvm_timer_frequency;
344 };
345 
346 OBJECT_DECLARE_CPU_TYPE(RISCVCPU, RISCVCPUClass, RISCV_CPU)
347 
348 /**
349  * RISCVCPUClass:
350  * @parent_realize: The parent class' realize handler.
351  * @parent_reset: The parent class' reset handler.
352  *
353  * A RISCV CPU model.
354  */
355 struct RISCVCPUClass {
356     /*< private >*/
357     CPUClass parent_class;
358     /*< public >*/
359     DeviceRealize parent_realize;
360     DeviceReset parent_reset;
361 };
362 
363 struct RISCVCPUConfig {
364     bool ext_i;
365     bool ext_e;
366     bool ext_g;
367     bool ext_m;
368     bool ext_a;
369     bool ext_f;
370     bool ext_d;
371     bool ext_c;
372     bool ext_s;
373     bool ext_u;
374     bool ext_h;
375     bool ext_j;
376     bool ext_v;
377     bool ext_zba;
378     bool ext_zbb;
379     bool ext_zbc;
380     bool ext_zbkb;
381     bool ext_zbkc;
382     bool ext_zbkx;
383     bool ext_zbs;
384     bool ext_zk;
385     bool ext_zkn;
386     bool ext_zknd;
387     bool ext_zkne;
388     bool ext_zknh;
389     bool ext_zkr;
390     bool ext_zks;
391     bool ext_zksed;
392     bool ext_zksh;
393     bool ext_zkt;
394     bool ext_counters;
395     bool ext_ifencei;
396     bool ext_icsr;
397     bool ext_svinval;
398     bool ext_svnapot;
399     bool ext_svpbmt;
400     bool ext_zdinx;
401     bool ext_zfh;
402     bool ext_zfhmin;
403     bool ext_zfinx;
404     bool ext_zhinx;
405     bool ext_zhinxmin;
406     bool ext_zve32f;
407     bool ext_zve64f;
408 
409     uint32_t mvendorid;
410     uint64_t marchid;
411     uint64_t mimpid;
412 
413     /* Vendor-specific custom extensions */
414     bool ext_XVentanaCondOps;
415 
416     char *priv_spec;
417     char *user_spec;
418     char *bext_spec;
419     char *vext_spec;
420     uint16_t vlen;
421     uint16_t elen;
422     bool mmu;
423     bool pmp;
424     bool epmp;
425     bool aia;
426     bool debug;
427     uint64_t resetvec;
428 
429     bool short_isa_string;
430 };
431 
432 typedef struct RISCVCPUConfig RISCVCPUConfig;
433 
434 /**
435  * RISCVCPU:
436  * @env: #CPURISCVState
437  *
438  * A RISCV CPU.
439  */
440 struct ArchCPU {
441     /*< private >*/
442     CPUState parent_obj;
443     /*< public >*/
444     CPUNegativeOffsetState neg;
445     CPURISCVState env;
446 
447     char *dyn_csr_xml;
448     char *dyn_vreg_xml;
449 
450     /* Configuration Settings */
451     RISCVCPUConfig cfg;
452 };
453 
454 static inline int riscv_has_ext(CPURISCVState *env, target_ulong ext)
455 {
456     return (env->misa_ext & ext) != 0;
457 }
458 
459 static inline bool riscv_feature(CPURISCVState *env, int feature)
460 {
461     return env->features & (1ULL << feature);
462 }
463 
464 static inline void riscv_set_feature(CPURISCVState *env, int feature)
465 {
466     env->features |= (1ULL << feature);
467 }
468 
469 #include "cpu_user.h"
470 
471 extern const char * const riscv_int_regnames[];
472 extern const char * const riscv_int_regnamesh[];
473 extern const char * const riscv_fpr_regnames[];
474 
475 const char *riscv_cpu_get_trap_name(target_ulong cause, bool async);
476 void riscv_cpu_do_interrupt(CPUState *cpu);
477 int riscv_cpu_write_elf64_note(WriteCoreDumpFunction f, CPUState *cs,
478                                int cpuid, void *opaque);
479 int riscv_cpu_write_elf32_note(WriteCoreDumpFunction f, CPUState *cs,
480                                int cpuid, void *opaque);
481 int riscv_cpu_gdb_read_register(CPUState *cpu, GByteArray *buf, int reg);
482 int riscv_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);
483 int riscv_cpu_hviprio_index2irq(int index, int *out_irq, int *out_rdzero);
484 uint8_t riscv_cpu_default_priority(int irq);
485 int riscv_cpu_mirq_pending(CPURISCVState *env);
486 int riscv_cpu_sirq_pending(CPURISCVState *env);
487 int riscv_cpu_vsirq_pending(CPURISCVState *env);
488 bool riscv_cpu_fp_enabled(CPURISCVState *env);
489 target_ulong riscv_cpu_get_geilen(CPURISCVState *env);
490 void riscv_cpu_set_geilen(CPURISCVState *env, target_ulong geilen);
491 bool riscv_cpu_vector_enabled(CPURISCVState *env);
492 bool riscv_cpu_virt_enabled(CPURISCVState *env);
493 void riscv_cpu_set_virt_enabled(CPURISCVState *env, bool enable);
494 bool riscv_cpu_two_stage_lookup(int mmu_idx);
495 int riscv_cpu_mmu_index(CPURISCVState *env, bool ifetch);
496 hwaddr riscv_cpu_get_phys_page_debug(CPUState *cpu, vaddr addr);
497 G_NORETURN void  riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
498                                                MMUAccessType access_type, int mmu_idx,
499                                                uintptr_t retaddr);
500 bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
501                         MMUAccessType access_type, int mmu_idx,
502                         bool probe, uintptr_t retaddr);
503 void riscv_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr,
504                                      vaddr addr, unsigned size,
505                                      MMUAccessType access_type,
506                                      int mmu_idx, MemTxAttrs attrs,
507                                      MemTxResult response, uintptr_t retaddr);
508 char *riscv_isa_string(RISCVCPU *cpu);
509 void riscv_cpu_list(void);
510 
511 #define cpu_list riscv_cpu_list
512 #define cpu_mmu_index riscv_cpu_mmu_index
513 
514 #ifndef CONFIG_USER_ONLY
515 bool riscv_cpu_exec_interrupt(CPUState *cs, int interrupt_request);
516 void riscv_cpu_swap_hypervisor_regs(CPURISCVState *env);
517 int riscv_cpu_claim_interrupts(RISCVCPU *cpu, uint64_t interrupts);
518 uint64_t riscv_cpu_update_mip(RISCVCPU *cpu, uint64_t mask, uint64_t value);
519 #define BOOL_TO_MASK(x) (-!!(x)) /* helper for riscv_cpu_update_mip value */
520 void riscv_cpu_set_rdtime_fn(CPURISCVState *env, uint64_t (*fn)(void *),
521                              void *arg);
522 void riscv_cpu_set_aia_ireg_rmw_fn(CPURISCVState *env, uint32_t priv,
523                                    int (*rmw_fn)(void *arg,
524                                                  target_ulong reg,
525                                                  target_ulong *val,
526                                                  target_ulong new_val,
527                                                  target_ulong write_mask),
528                                    void *rmw_fn_arg);
529 #endif
530 void riscv_cpu_set_mode(CPURISCVState *env, target_ulong newpriv);
531 
532 void riscv_translate_init(void);
533 G_NORETURN void riscv_raise_exception(CPURISCVState *env,
534                                       uint32_t exception, uintptr_t pc);
535 
536 target_ulong riscv_cpu_get_fflags(CPURISCVState *env);
537 void riscv_cpu_set_fflags(CPURISCVState *env, target_ulong);
538 
539 #define TB_FLAGS_PRIV_MMU_MASK                3
540 #define TB_FLAGS_PRIV_HYP_ACCESS_MASK   (1 << 2)
541 #define TB_FLAGS_MSTATUS_FS MSTATUS_FS
542 #define TB_FLAGS_MSTATUS_VS MSTATUS_VS
543 
544 #include "exec/cpu-all.h"
545 
546 FIELD(TB_FLAGS, MEM_IDX, 0, 3)
547 FIELD(TB_FLAGS, LMUL, 3, 3)
548 FIELD(TB_FLAGS, SEW, 6, 3)
549 /* Skip MSTATUS_VS (0x600) bits */
550 FIELD(TB_FLAGS, VL_EQ_VLMAX, 11, 1)
551 FIELD(TB_FLAGS, VILL, 12, 1)
552 /* Skip MSTATUS_FS (0x6000) bits */
553 /* Is a Hypervisor instruction load/store allowed? */
554 FIELD(TB_FLAGS, HLSX, 15, 1)
555 FIELD(TB_FLAGS, MSTATUS_HS_FS, 16, 2)
556 FIELD(TB_FLAGS, MSTATUS_HS_VS, 18, 2)
557 /* The combination of MXL/SXL/UXL that applies to the current cpu mode. */
558 FIELD(TB_FLAGS, XL, 20, 2)
559 /* If PointerMasking should be applied */
560 FIELD(TB_FLAGS, PM_MASK_ENABLED, 22, 1)
561 FIELD(TB_FLAGS, PM_BASE_ENABLED, 23, 1)
562 
563 #ifdef TARGET_RISCV32
564 #define riscv_cpu_mxl(env)  ((void)(env), MXL_RV32)
565 #else
566 static inline RISCVMXL riscv_cpu_mxl(CPURISCVState *env)
567 {
568     return env->misa_mxl;
569 }
570 #endif
571 #define riscv_cpu_mxl_bits(env) (1UL << (4 + riscv_cpu_mxl(env)))
572 
573 #if defined(TARGET_RISCV32)
574 #define cpu_recompute_xl(env)  ((void)(env), MXL_RV32)
575 #else
576 static inline RISCVMXL cpu_recompute_xl(CPURISCVState *env)
577 {
578     RISCVMXL xl = env->misa_mxl;
579 #if !defined(CONFIG_USER_ONLY)
580     /*
581      * When emulating a 32-bit-only cpu, use RV32.
582      * When emulating a 64-bit cpu, and MXL has been reduced to RV32,
583      * MSTATUSH doesn't have UXL/SXL, therefore XLEN cannot be widened
584      * back to RV64 for lower privs.
585      */
586     if (xl != MXL_RV32) {
587         switch (env->priv) {
588         case PRV_M:
589             break;
590         case PRV_U:
591             xl = get_field(env->mstatus, MSTATUS64_UXL);
592             break;
593         default: /* PRV_S | PRV_H */
594             xl = get_field(env->mstatus, MSTATUS64_SXL);
595             break;
596         }
597     }
598 #endif
599     return xl;
600 }
601 #endif
602 
603 static inline int riscv_cpu_xlen(CPURISCVState *env)
604 {
605     return 16 << env->xl;
606 }
607 
608 #ifdef TARGET_RISCV32
609 #define riscv_cpu_sxl(env)  ((void)(env), MXL_RV32)
610 #else
611 static inline RISCVMXL riscv_cpu_sxl(CPURISCVState *env)
612 {
613 #ifdef CONFIG_USER_ONLY
614     return env->misa_mxl;
615 #else
616     return get_field(env->mstatus, MSTATUS64_SXL);
617 #endif
618 }
619 #endif
620 
621 /*
622  * Encode LMUL to lmul as follows:
623  *     LMUL    vlmul    lmul
624  *      1       000       0
625  *      2       001       1
626  *      4       010       2
627  *      8       011       3
628  *      -       100       -
629  *     1/8      101      -3
630  *     1/4      110      -2
631  *     1/2      111      -1
632  *
633  * then, we can calculate VLMAX = vlen >> (vsew + 3 - lmul)
634  * e.g. vlen = 256 bits, SEW = 16, LMUL = 1/8
635  *      => VLMAX = vlen >> (1 + 3 - (-3))
636  *               = 256 >> 7
637  *               = 2
638  */
639 static inline uint32_t vext_get_vlmax(RISCVCPU *cpu, target_ulong vtype)
640 {
641     uint8_t sew = FIELD_EX64(vtype, VTYPE, VSEW);
642     int8_t lmul = sextract32(FIELD_EX64(vtype, VTYPE, VLMUL), 0, 3);
643     return cpu->cfg.vlen >> (sew + 3 - lmul);
644 }
645 
646 void cpu_get_tb_cpu_state(CPURISCVState *env, target_ulong *pc,
647                           target_ulong *cs_base, uint32_t *pflags);
648 
649 void riscv_cpu_update_mask(CPURISCVState *env);
650 
651 RISCVException riscv_csrrw(CPURISCVState *env, int csrno,
652                            target_ulong *ret_value,
653                            target_ulong new_value, target_ulong write_mask);
654 RISCVException riscv_csrrw_debug(CPURISCVState *env, int csrno,
655                                  target_ulong *ret_value,
656                                  target_ulong new_value,
657                                  target_ulong write_mask);
658 
659 static inline void riscv_csr_write(CPURISCVState *env, int csrno,
660                                    target_ulong val)
661 {
662     riscv_csrrw(env, csrno, NULL, val, MAKE_64BIT_MASK(0, TARGET_LONG_BITS));
663 }
664 
665 static inline target_ulong riscv_csr_read(CPURISCVState *env, int csrno)
666 {
667     target_ulong val = 0;
668     riscv_csrrw(env, csrno, &val, 0, 0);
669     return val;
670 }
671 
672 typedef RISCVException (*riscv_csr_predicate_fn)(CPURISCVState *env,
673                                                  int csrno);
674 typedef RISCVException (*riscv_csr_read_fn)(CPURISCVState *env, int csrno,
675                                             target_ulong *ret_value);
676 typedef RISCVException (*riscv_csr_write_fn)(CPURISCVState *env, int csrno,
677                                              target_ulong new_value);
678 typedef RISCVException (*riscv_csr_op_fn)(CPURISCVState *env, int csrno,
679                                           target_ulong *ret_value,
680                                           target_ulong new_value,
681                                           target_ulong write_mask);
682 
683 RISCVException riscv_csrrw_i128(CPURISCVState *env, int csrno,
684                                 Int128 *ret_value,
685                                 Int128 new_value, Int128 write_mask);
686 
687 typedef RISCVException (*riscv_csr_read128_fn)(CPURISCVState *env, int csrno,
688                                                Int128 *ret_value);
689 typedef RISCVException (*riscv_csr_write128_fn)(CPURISCVState *env, int csrno,
690                                              Int128 new_value);
691 
692 typedef struct {
693     const char *name;
694     riscv_csr_predicate_fn predicate;
695     riscv_csr_read_fn read;
696     riscv_csr_write_fn write;
697     riscv_csr_op_fn op;
698     riscv_csr_read128_fn read128;
699     riscv_csr_write128_fn write128;
700     /* The default priv spec version should be PRIV_VERSION_1_10_0 (i.e 0) */
701     uint32_t min_priv_ver;
702 } riscv_csr_operations;
703 
704 /* CSR function table constants */
705 enum {
706     CSR_TABLE_SIZE = 0x1000
707 };
708 
709 /* CSR function table */
710 extern riscv_csr_operations csr_ops[CSR_TABLE_SIZE];
711 
712 void riscv_get_csr_ops(int csrno, riscv_csr_operations *ops);
713 void riscv_set_csr_ops(int csrno, riscv_csr_operations *ops);
714 
715 void riscv_cpu_register_gdb_regs_for_features(CPUState *cs);
716 
717 #endif /* RISCV_CPU_H */
718