xref: /openbmc/qemu/target/riscv/cpu.h (revision eef11ce3)
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 resetvec;
165 
166     target_ulong mhartid;
167     /*
168      * For RV32 this is 32-bit mstatus and 32-bit mstatush.
169      * For RV64 this is a 64-bit mstatus.
170      */
171     uint64_t mstatus;
172 
173     target_ulong mip;
174 
175     uint32_t miclaim;
176 
177     target_ulong mie;
178     target_ulong mideleg;
179 
180     target_ulong satp;   /* since: priv-1.10.0 */
181     target_ulong stval;
182     target_ulong medeleg;
183 
184     target_ulong stvec;
185     target_ulong sepc;
186     target_ulong scause;
187 
188     target_ulong mtvec;
189     target_ulong mepc;
190     target_ulong mcause;
191     target_ulong mtval;  /* since: priv-1.10.0 */
192 
193     /* Hypervisor CSRs */
194     target_ulong hstatus;
195     target_ulong hedeleg;
196     target_ulong hideleg;
197     target_ulong hcounteren;
198     target_ulong htval;
199     target_ulong htinst;
200     target_ulong hgatp;
201     uint64_t htimedelta;
202 
203     /* Upper 64-bits of 128-bit CSRs */
204     uint64_t mscratchh;
205     uint64_t sscratchh;
206 
207     /* Virtual CSRs */
208     /*
209      * For RV32 this is 32-bit vsstatus and 32-bit vsstatush.
210      * For RV64 this is a 64-bit vsstatus.
211      */
212     uint64_t vsstatus;
213     target_ulong vstvec;
214     target_ulong vsscratch;
215     target_ulong vsepc;
216     target_ulong vscause;
217     target_ulong vstval;
218     target_ulong vsatp;
219 
220     target_ulong mtval2;
221     target_ulong mtinst;
222 
223     /* HS Backup CSRs */
224     target_ulong stvec_hs;
225     target_ulong sscratch_hs;
226     target_ulong sepc_hs;
227     target_ulong scause_hs;
228     target_ulong stval_hs;
229     target_ulong satp_hs;
230     uint64_t mstatus_hs;
231 
232     /* Signals whether the current exception occurred with two-stage address
233        translation active. */
234     bool two_stage_lookup;
235 
236     target_ulong scounteren;
237     target_ulong mcounteren;
238 
239     target_ulong sscratch;
240     target_ulong mscratch;
241 
242     /* temporary htif regs */
243     uint64_t mfromhost;
244     uint64_t mtohost;
245     uint64_t timecmp;
246 
247     /* physical memory protection */
248     pmp_table_t pmp_state;
249     target_ulong mseccfg;
250 
251     /* machine specific rdtime callback */
252     uint64_t (*rdtime_fn)(uint32_t);
253     uint32_t rdtime_fn_arg;
254 
255     /* True if in debugger mode.  */
256     bool debugger;
257 
258     /*
259      * CSRs for PointerMasking extension
260      */
261     target_ulong mmte;
262     target_ulong mpmmask;
263     target_ulong mpmbase;
264     target_ulong spmmask;
265     target_ulong spmbase;
266     target_ulong upmmask;
267     target_ulong upmbase;
268 #endif
269     target_ulong cur_pmmask;
270     target_ulong cur_pmbase;
271 
272     float_status fp_status;
273 
274     /* Fields from here on are preserved across CPU reset. */
275     QEMUTimer *timer; /* Internal timer */
276 
277     hwaddr kernel_addr;
278     hwaddr fdt_addr;
279 
280     /* kvm timer */
281     bool kvm_timer_dirty;
282     uint64_t kvm_timer_time;
283     uint64_t kvm_timer_compare;
284     uint64_t kvm_timer_state;
285     uint64_t kvm_timer_frequency;
286 };
287 
288 OBJECT_DECLARE_TYPE(RISCVCPU, RISCVCPUClass,
289                     RISCV_CPU)
290 
291 /**
292  * RISCVCPUClass:
293  * @parent_realize: The parent class' realize handler.
294  * @parent_reset: The parent class' reset handler.
295  *
296  * A RISCV CPU model.
297  */
298 struct RISCVCPUClass {
299     /*< private >*/
300     CPUClass parent_class;
301     /*< public >*/
302     DeviceRealize parent_realize;
303     DeviceReset parent_reset;
304 };
305 
306 /**
307  * RISCVCPU:
308  * @env: #CPURISCVState
309  *
310  * A RISCV CPU.
311  */
312 struct RISCVCPU {
313     /*< private >*/
314     CPUState parent_obj;
315     /*< public >*/
316     CPUNegativeOffsetState neg;
317     CPURISCVState env;
318 
319     char *dyn_csr_xml;
320     char *dyn_vreg_xml;
321 
322     /* Configuration Settings */
323     struct {
324         bool ext_i;
325         bool ext_e;
326         bool ext_g;
327         bool ext_m;
328         bool ext_a;
329         bool ext_f;
330         bool ext_d;
331         bool ext_c;
332         bool ext_s;
333         bool ext_u;
334         bool ext_h;
335         bool ext_j;
336         bool ext_v;
337         bool ext_zba;
338         bool ext_zbb;
339         bool ext_zbc;
340         bool ext_zbs;
341         bool ext_counters;
342         bool ext_ifencei;
343         bool ext_icsr;
344         bool ext_zfh;
345         bool ext_zfhmin;
346         bool ext_zve32f;
347         bool ext_zve64f;
348 
349         char *priv_spec;
350         char *user_spec;
351         char *bext_spec;
352         char *vext_spec;
353         uint16_t vlen;
354         uint16_t elen;
355         bool mmu;
356         bool pmp;
357         bool epmp;
358         uint64_t resetvec;
359     } cfg;
360 };
361 
362 static inline int riscv_has_ext(CPURISCVState *env, target_ulong ext)
363 {
364     return (env->misa_ext & ext) != 0;
365 }
366 
367 static inline bool riscv_feature(CPURISCVState *env, int feature)
368 {
369     return env->features & (1ULL << feature);
370 }
371 
372 #include "cpu_user.h"
373 
374 extern const char * const riscv_int_regnames[];
375 extern const char * const riscv_int_regnamesh[];
376 extern const char * const riscv_fpr_regnames[];
377 
378 const char *riscv_cpu_get_trap_name(target_ulong cause, bool async);
379 void riscv_cpu_do_interrupt(CPUState *cpu);
380 int riscv_cpu_write_elf64_note(WriteCoreDumpFunction f, CPUState *cs,
381                                int cpuid, void *opaque);
382 int riscv_cpu_write_elf32_note(WriteCoreDumpFunction f, CPUState *cs,
383                                int cpuid, void *opaque);
384 int riscv_cpu_gdb_read_register(CPUState *cpu, GByteArray *buf, int reg);
385 int riscv_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);
386 bool riscv_cpu_fp_enabled(CPURISCVState *env);
387 bool riscv_cpu_vector_enabled(CPURISCVState *env);
388 bool riscv_cpu_virt_enabled(CPURISCVState *env);
389 void riscv_cpu_set_virt_enabled(CPURISCVState *env, bool enable);
390 bool riscv_cpu_two_stage_lookup(int mmu_idx);
391 int riscv_cpu_mmu_index(CPURISCVState *env, bool ifetch);
392 hwaddr riscv_cpu_get_phys_page_debug(CPUState *cpu, vaddr addr);
393 void  riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
394                                     MMUAccessType access_type, int mmu_idx,
395                                     uintptr_t retaddr) QEMU_NORETURN;
396 bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
397                         MMUAccessType access_type, int mmu_idx,
398                         bool probe, uintptr_t retaddr);
399 void riscv_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr,
400                                      vaddr addr, unsigned size,
401                                      MMUAccessType access_type,
402                                      int mmu_idx, MemTxAttrs attrs,
403                                      MemTxResult response, uintptr_t retaddr);
404 char *riscv_isa_string(RISCVCPU *cpu);
405 void riscv_cpu_list(void);
406 
407 #define cpu_list riscv_cpu_list
408 #define cpu_mmu_index riscv_cpu_mmu_index
409 
410 #ifndef CONFIG_USER_ONLY
411 bool riscv_cpu_exec_interrupt(CPUState *cs, int interrupt_request);
412 void riscv_cpu_swap_hypervisor_regs(CPURISCVState *env);
413 int riscv_cpu_claim_interrupts(RISCVCPU *cpu, uint32_t interrupts);
414 uint32_t riscv_cpu_update_mip(RISCVCPU *cpu, uint32_t mask, uint32_t value);
415 #define BOOL_TO_MASK(x) (-!!(x)) /* helper for riscv_cpu_update_mip value */
416 void riscv_cpu_set_rdtime_fn(CPURISCVState *env, uint64_t (*fn)(uint32_t),
417                              uint32_t arg);
418 #endif
419 void riscv_cpu_set_mode(CPURISCVState *env, target_ulong newpriv);
420 
421 void riscv_translate_init(void);
422 void QEMU_NORETURN riscv_raise_exception(CPURISCVState *env,
423                                          uint32_t exception, uintptr_t pc);
424 
425 target_ulong riscv_cpu_get_fflags(CPURISCVState *env);
426 void riscv_cpu_set_fflags(CPURISCVState *env, target_ulong);
427 
428 #define TB_FLAGS_PRIV_MMU_MASK                3
429 #define TB_FLAGS_PRIV_HYP_ACCESS_MASK   (1 << 2)
430 #define TB_FLAGS_MSTATUS_FS MSTATUS_FS
431 #define TB_FLAGS_MSTATUS_VS MSTATUS_VS
432 
433 typedef CPURISCVState CPUArchState;
434 typedef RISCVCPU ArchCPU;
435 #include "exec/cpu-all.h"
436 
437 FIELD(TB_FLAGS, MEM_IDX, 0, 3)
438 FIELD(TB_FLAGS, LMUL, 3, 3)
439 FIELD(TB_FLAGS, SEW, 6, 3)
440 /* Skip MSTATUS_VS (0x600) bits */
441 FIELD(TB_FLAGS, VL_EQ_VLMAX, 11, 1)
442 FIELD(TB_FLAGS, VILL, 12, 1)
443 /* Skip MSTATUS_FS (0x6000) bits */
444 /* Is a Hypervisor instruction load/store allowed? */
445 FIELD(TB_FLAGS, HLSX, 15, 1)
446 FIELD(TB_FLAGS, MSTATUS_HS_FS, 16, 2)
447 FIELD(TB_FLAGS, MSTATUS_HS_VS, 18, 2)
448 /* The combination of MXL/SXL/UXL that applies to the current cpu mode. */
449 FIELD(TB_FLAGS, XL, 20, 2)
450 /* If PointerMasking should be applied */
451 FIELD(TB_FLAGS, PM_MASK_ENABLED, 22, 1)
452 FIELD(TB_FLAGS, PM_BASE_ENABLED, 23, 1)
453 
454 #ifdef TARGET_RISCV32
455 #define riscv_cpu_mxl(env)  ((void)(env), MXL_RV32)
456 #else
457 static inline RISCVMXL riscv_cpu_mxl(CPURISCVState *env)
458 {
459     return env->misa_mxl;
460 }
461 #endif
462 
463 #if defined(TARGET_RISCV32)
464 #define cpu_recompute_xl(env)  ((void)(env), MXL_RV32)
465 #else
466 static inline RISCVMXL cpu_recompute_xl(CPURISCVState *env)
467 {
468     RISCVMXL xl = env->misa_mxl;
469 #if !defined(CONFIG_USER_ONLY)
470     /*
471      * When emulating a 32-bit-only cpu, use RV32.
472      * When emulating a 64-bit cpu, and MXL has been reduced to RV32,
473      * MSTATUSH doesn't have UXL/SXL, therefore XLEN cannot be widened
474      * back to RV64 for lower privs.
475      */
476     if (xl != MXL_RV32) {
477         switch (env->priv) {
478         case PRV_M:
479             break;
480         case PRV_U:
481             xl = get_field(env->mstatus, MSTATUS64_UXL);
482             break;
483         default: /* PRV_S | PRV_H */
484             xl = get_field(env->mstatus, MSTATUS64_SXL);
485             break;
486         }
487     }
488 #endif
489     return xl;
490 }
491 #endif
492 
493 static inline int riscv_cpu_xlen(CPURISCVState *env)
494 {
495     return 16 << env->xl;
496 }
497 
498 /*
499  * Encode LMUL to lmul as follows:
500  *     LMUL    vlmul    lmul
501  *      1       000       0
502  *      2       001       1
503  *      4       010       2
504  *      8       011       3
505  *      -       100       -
506  *     1/8      101      -3
507  *     1/4      110      -2
508  *     1/2      111      -1
509  *
510  * then, we can calculate VLMAX = vlen >> (vsew + 3 - lmul)
511  * e.g. vlen = 256 bits, SEW = 16, LMUL = 1/8
512  *      => VLMAX = vlen >> (1 + 3 - (-3))
513  *               = 256 >> 7
514  *               = 2
515  */
516 static inline uint32_t vext_get_vlmax(RISCVCPU *cpu, target_ulong vtype)
517 {
518     uint8_t sew = FIELD_EX64(vtype, VTYPE, VSEW);
519     int8_t lmul = sextract32(FIELD_EX64(vtype, VTYPE, VLMUL), 0, 3);
520     return cpu->cfg.vlen >> (sew + 3 - lmul);
521 }
522 
523 void cpu_get_tb_cpu_state(CPURISCVState *env, target_ulong *pc,
524                           target_ulong *cs_base, uint32_t *pflags);
525 
526 void riscv_cpu_update_mask(CPURISCVState *env);
527 
528 RISCVException riscv_csrrw(CPURISCVState *env, int csrno,
529                            target_ulong *ret_value,
530                            target_ulong new_value, target_ulong write_mask);
531 RISCVException riscv_csrrw_debug(CPURISCVState *env, int csrno,
532                                  target_ulong *ret_value,
533                                  target_ulong new_value,
534                                  target_ulong write_mask);
535 
536 static inline void riscv_csr_write(CPURISCVState *env, int csrno,
537                                    target_ulong val)
538 {
539     riscv_csrrw(env, csrno, NULL, val, MAKE_64BIT_MASK(0, TARGET_LONG_BITS));
540 }
541 
542 static inline target_ulong riscv_csr_read(CPURISCVState *env, int csrno)
543 {
544     target_ulong val = 0;
545     riscv_csrrw(env, csrno, &val, 0, 0);
546     return val;
547 }
548 
549 typedef RISCVException (*riscv_csr_predicate_fn)(CPURISCVState *env,
550                                                  int csrno);
551 typedef RISCVException (*riscv_csr_read_fn)(CPURISCVState *env, int csrno,
552                                             target_ulong *ret_value);
553 typedef RISCVException (*riscv_csr_write_fn)(CPURISCVState *env, int csrno,
554                                              target_ulong new_value);
555 typedef RISCVException (*riscv_csr_op_fn)(CPURISCVState *env, int csrno,
556                                           target_ulong *ret_value,
557                                           target_ulong new_value,
558                                           target_ulong write_mask);
559 
560 RISCVException riscv_csrrw_i128(CPURISCVState *env, int csrno,
561                                 Int128 *ret_value,
562                                 Int128 new_value, Int128 write_mask);
563 
564 typedef RISCVException (*riscv_csr_read128_fn)(CPURISCVState *env, int csrno,
565                                                Int128 *ret_value);
566 typedef RISCVException (*riscv_csr_write128_fn)(CPURISCVState *env, int csrno,
567                                              Int128 new_value);
568 
569 typedef struct {
570     const char *name;
571     riscv_csr_predicate_fn predicate;
572     riscv_csr_read_fn read;
573     riscv_csr_write_fn write;
574     riscv_csr_op_fn op;
575     riscv_csr_read128_fn read128;
576     riscv_csr_write128_fn write128;
577 } riscv_csr_operations;
578 
579 /* CSR function table constants */
580 enum {
581     CSR_TABLE_SIZE = 0x1000
582 };
583 
584 /* CSR function table */
585 extern riscv_csr_operations csr_ops[CSR_TABLE_SIZE];
586 
587 void riscv_get_csr_ops(int csrno, riscv_csr_operations *ops);
588 void riscv_set_csr_ops(int csrno, riscv_csr_operations *ops);
589 
590 void riscv_cpu_register_gdb_regs_for_features(CPUState *cs);
591 
592 #endif /* RISCV_CPU_H */
593