xref: /openbmc/qemu/target/riscv/cpu.h (revision d96a271a)
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 FIELD(VTYPE, VILL, sizeof(target_ulong) * 8 - 1, 1)
115 
116 struct CPURISCVState {
117     target_ulong gpr[32];
118     target_ulong gprh[32]; /* 64 top bits of the 128-bit registers */
119     uint64_t fpr[32]; /* assume both F and D extensions */
120 
121     /* vector coprocessor state. */
122     uint64_t vreg[32 * RV_VLEN_MAX / 64] QEMU_ALIGNED(16);
123     target_ulong vxrm;
124     target_ulong vxsat;
125     target_ulong vl;
126     target_ulong vstart;
127     target_ulong vtype;
128     bool vill;
129 
130     target_ulong pc;
131     target_ulong load_res;
132     target_ulong load_val;
133 
134     target_ulong frm;
135 
136     target_ulong badaddr;
137     uint32_t bins;
138 
139     target_ulong guest_phys_fault_addr;
140 
141     target_ulong priv_ver;
142     target_ulong bext_ver;
143     target_ulong vext_ver;
144 
145     /* RISCVMXL, but uint32_t for vmstate migration */
146     uint32_t misa_mxl;      /* current mxl */
147     uint32_t misa_mxl_max;  /* max mxl for this cpu */
148     uint32_t misa_ext;      /* current extensions */
149     uint32_t misa_ext_mask; /* max ext for this cpu */
150     uint32_t xl;            /* current xlen */
151 
152     /* 128-bit helpers upper part return value */
153     target_ulong retxh;
154 
155     uint32_t features;
156 
157 #ifdef CONFIG_USER_ONLY
158     uint32_t elf_flags;
159 #endif
160 
161 #ifndef CONFIG_USER_ONLY
162     target_ulong priv;
163     /* This contains QEMU specific information about the virt state. */
164     target_ulong virt;
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     uint64_t htimedelta;
203 
204     /* Upper 64-bits of 128-bit CSRs */
205     uint64_t mscratchh;
206     uint64_t sscratchh;
207 
208     /* Virtual CSRs */
209     /*
210      * For RV32 this is 32-bit vsstatus and 32-bit vsstatush.
211      * For RV64 this is a 64-bit vsstatus.
212      */
213     uint64_t vsstatus;
214     target_ulong vstvec;
215     target_ulong vsscratch;
216     target_ulong vsepc;
217     target_ulong vscause;
218     target_ulong vstval;
219     target_ulong vsatp;
220 
221     target_ulong mtval2;
222     target_ulong mtinst;
223 
224     /* HS Backup CSRs */
225     target_ulong stvec_hs;
226     target_ulong sscratch_hs;
227     target_ulong sepc_hs;
228     target_ulong scause_hs;
229     target_ulong stval_hs;
230     target_ulong satp_hs;
231     uint64_t mstatus_hs;
232 
233     /* Signals whether the current exception occurred with two-stage address
234        translation active. */
235     bool two_stage_lookup;
236 
237     target_ulong scounteren;
238     target_ulong mcounteren;
239 
240     target_ulong sscratch;
241     target_ulong mscratch;
242 
243     /* temporary htif regs */
244     uint64_t mfromhost;
245     uint64_t mtohost;
246     uint64_t timecmp;
247 
248     /* physical memory protection */
249     pmp_table_t pmp_state;
250     target_ulong mseccfg;
251 
252     /* machine specific rdtime callback */
253     uint64_t (*rdtime_fn)(uint32_t);
254     uint32_t rdtime_fn_arg;
255 
256     /* True if in debugger mode.  */
257     bool debugger;
258 
259     /*
260      * CSRs for PointerMasking extension
261      */
262     target_ulong mmte;
263     target_ulong mpmmask;
264     target_ulong mpmbase;
265     target_ulong spmmask;
266     target_ulong spmbase;
267     target_ulong upmmask;
268     target_ulong upmbase;
269 #endif
270     target_ulong cur_pmmask;
271     target_ulong cur_pmbase;
272 
273     float_status fp_status;
274 
275     /* Fields from here on are preserved across CPU reset. */
276     QEMUTimer *timer; /* Internal timer */
277 
278     hwaddr kernel_addr;
279     hwaddr fdt_addr;
280 
281     /* kvm timer */
282     bool kvm_timer_dirty;
283     uint64_t kvm_timer_time;
284     uint64_t kvm_timer_compare;
285     uint64_t kvm_timer_state;
286     uint64_t kvm_timer_frequency;
287 };
288 
289 OBJECT_DECLARE_TYPE(RISCVCPU, RISCVCPUClass,
290                     RISCV_CPU)
291 
292 /**
293  * RISCVCPUClass:
294  * @parent_realize: The parent class' realize handler.
295  * @parent_reset: The parent class' reset handler.
296  *
297  * A RISCV CPU model.
298  */
299 struct RISCVCPUClass {
300     /*< private >*/
301     CPUClass parent_class;
302     /*< public >*/
303     DeviceRealize parent_realize;
304     DeviceReset parent_reset;
305 };
306 
307 /**
308  * RISCVCPU:
309  * @env: #CPURISCVState
310  *
311  * A RISCV CPU.
312  */
313 struct RISCVCPU {
314     /*< private >*/
315     CPUState parent_obj;
316     /*< public >*/
317     CPUNegativeOffsetState neg;
318     CPURISCVState env;
319 
320     char *dyn_csr_xml;
321     char *dyn_vreg_xml;
322 
323     /* Configuration Settings */
324     struct {
325         bool ext_i;
326         bool ext_e;
327         bool ext_g;
328         bool ext_m;
329         bool ext_a;
330         bool ext_f;
331         bool ext_d;
332         bool ext_c;
333         bool ext_s;
334         bool ext_u;
335         bool ext_h;
336         bool ext_j;
337         bool ext_v;
338         bool ext_zba;
339         bool ext_zbb;
340         bool ext_zbc;
341         bool ext_zbs;
342         bool ext_counters;
343         bool ext_ifencei;
344         bool ext_icsr;
345         bool ext_zfh;
346         bool ext_zfhmin;
347         bool ext_zve32f;
348         bool ext_zve64f;
349 
350         char *priv_spec;
351         char *user_spec;
352         char *bext_spec;
353         char *vext_spec;
354         uint16_t vlen;
355         uint16_t elen;
356         bool mmu;
357         bool pmp;
358         bool epmp;
359         uint64_t resetvec;
360     } cfg;
361 };
362 
363 static inline int riscv_has_ext(CPURISCVState *env, target_ulong ext)
364 {
365     return (env->misa_ext & ext) != 0;
366 }
367 
368 static inline bool riscv_feature(CPURISCVState *env, int feature)
369 {
370     return env->features & (1ULL << feature);
371 }
372 
373 #include "cpu_user.h"
374 
375 extern const char * const riscv_int_regnames[];
376 extern const char * const riscv_int_regnamesh[];
377 extern const char * const riscv_fpr_regnames[];
378 
379 const char *riscv_cpu_get_trap_name(target_ulong cause, bool async);
380 void riscv_cpu_do_interrupt(CPUState *cpu);
381 int riscv_cpu_write_elf64_note(WriteCoreDumpFunction f, CPUState *cs,
382                                int cpuid, void *opaque);
383 int riscv_cpu_write_elf32_note(WriteCoreDumpFunction f, CPUState *cs,
384                                int cpuid, void *opaque);
385 int riscv_cpu_gdb_read_register(CPUState *cpu, GByteArray *buf, int reg);
386 int riscv_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);
387 bool riscv_cpu_fp_enabled(CPURISCVState *env);
388 bool riscv_cpu_vector_enabled(CPURISCVState *env);
389 bool riscv_cpu_virt_enabled(CPURISCVState *env);
390 void riscv_cpu_set_virt_enabled(CPURISCVState *env, bool enable);
391 bool riscv_cpu_two_stage_lookup(int mmu_idx);
392 int riscv_cpu_mmu_index(CPURISCVState *env, bool ifetch);
393 hwaddr riscv_cpu_get_phys_page_debug(CPUState *cpu, vaddr addr);
394 void  riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
395                                     MMUAccessType access_type, int mmu_idx,
396                                     uintptr_t retaddr) QEMU_NORETURN;
397 bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
398                         MMUAccessType access_type, int mmu_idx,
399                         bool probe, uintptr_t retaddr);
400 void riscv_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr,
401                                      vaddr addr, unsigned size,
402                                      MMUAccessType access_type,
403                                      int mmu_idx, MemTxAttrs attrs,
404                                      MemTxResult response, uintptr_t retaddr);
405 char *riscv_isa_string(RISCVCPU *cpu);
406 void riscv_cpu_list(void);
407 
408 #define cpu_list riscv_cpu_list
409 #define cpu_mmu_index riscv_cpu_mmu_index
410 
411 #ifndef CONFIG_USER_ONLY
412 bool riscv_cpu_exec_interrupt(CPUState *cs, int interrupt_request);
413 void riscv_cpu_swap_hypervisor_regs(CPURISCVState *env);
414 int riscv_cpu_claim_interrupts(RISCVCPU *cpu, uint32_t interrupts);
415 uint32_t riscv_cpu_update_mip(RISCVCPU *cpu, uint32_t mask, uint32_t value);
416 #define BOOL_TO_MASK(x) (-!!(x)) /* helper for riscv_cpu_update_mip value */
417 void riscv_cpu_set_rdtime_fn(CPURISCVState *env, uint64_t (*fn)(uint32_t),
418                              uint32_t arg);
419 #endif
420 void riscv_cpu_set_mode(CPURISCVState *env, target_ulong newpriv);
421 
422 void riscv_translate_init(void);
423 void QEMU_NORETURN riscv_raise_exception(CPURISCVState *env,
424                                          uint32_t exception, uintptr_t pc);
425 
426 target_ulong riscv_cpu_get_fflags(CPURISCVState *env);
427 void riscv_cpu_set_fflags(CPURISCVState *env, target_ulong);
428 
429 #define TB_FLAGS_PRIV_MMU_MASK                3
430 #define TB_FLAGS_PRIV_HYP_ACCESS_MASK   (1 << 2)
431 #define TB_FLAGS_MSTATUS_FS MSTATUS_FS
432 #define TB_FLAGS_MSTATUS_VS MSTATUS_VS
433 
434 typedef CPURISCVState CPUArchState;
435 typedef RISCVCPU ArchCPU;
436 #include "exec/cpu-all.h"
437 
438 FIELD(TB_FLAGS, MEM_IDX, 0, 3)
439 FIELD(TB_FLAGS, LMUL, 3, 3)
440 FIELD(TB_FLAGS, SEW, 6, 3)
441 /* Skip MSTATUS_VS (0x600) bits */
442 FIELD(TB_FLAGS, VL_EQ_VLMAX, 11, 1)
443 FIELD(TB_FLAGS, VILL, 12, 1)
444 /* Skip MSTATUS_FS (0x6000) bits */
445 /* Is a Hypervisor instruction load/store allowed? */
446 FIELD(TB_FLAGS, HLSX, 15, 1)
447 FIELD(TB_FLAGS, MSTATUS_HS_FS, 16, 2)
448 FIELD(TB_FLAGS, MSTATUS_HS_VS, 18, 2)
449 /* The combination of MXL/SXL/UXL that applies to the current cpu mode. */
450 FIELD(TB_FLAGS, XL, 20, 2)
451 /* If PointerMasking should be applied */
452 FIELD(TB_FLAGS, PM_MASK_ENABLED, 22, 1)
453 FIELD(TB_FLAGS, PM_BASE_ENABLED, 23, 1)
454 
455 #ifdef TARGET_RISCV32
456 #define riscv_cpu_mxl(env)  ((void)(env), MXL_RV32)
457 #else
458 static inline RISCVMXL riscv_cpu_mxl(CPURISCVState *env)
459 {
460     return env->misa_mxl;
461 }
462 #endif
463 
464 #if defined(TARGET_RISCV32)
465 #define cpu_recompute_xl(env)  ((void)(env), MXL_RV32)
466 #else
467 static inline RISCVMXL cpu_recompute_xl(CPURISCVState *env)
468 {
469     RISCVMXL xl = env->misa_mxl;
470 #if !defined(CONFIG_USER_ONLY)
471     /*
472      * When emulating a 32-bit-only cpu, use RV32.
473      * When emulating a 64-bit cpu, and MXL has been reduced to RV32,
474      * MSTATUSH doesn't have UXL/SXL, therefore XLEN cannot be widened
475      * back to RV64 for lower privs.
476      */
477     if (xl != MXL_RV32) {
478         switch (env->priv) {
479         case PRV_M:
480             break;
481         case PRV_U:
482             xl = get_field(env->mstatus, MSTATUS64_UXL);
483             break;
484         default: /* PRV_S | PRV_H */
485             xl = get_field(env->mstatus, MSTATUS64_SXL);
486             break;
487         }
488     }
489 #endif
490     return xl;
491 }
492 #endif
493 
494 /*
495  * Encode LMUL to lmul as follows:
496  *     LMUL    vlmul    lmul
497  *      1       000       0
498  *      2       001       1
499  *      4       010       2
500  *      8       011       3
501  *      -       100       -
502  *     1/8      101      -3
503  *     1/4      110      -2
504  *     1/2      111      -1
505  *
506  * then, we can calculate VLMAX = vlen >> (vsew + 3 - lmul)
507  * e.g. vlen = 256 bits, SEW = 16, LMUL = 1/8
508  *      => VLMAX = vlen >> (1 + 3 - (-3))
509  *               = 256 >> 7
510  *               = 2
511  */
512 static inline uint32_t vext_get_vlmax(RISCVCPU *cpu, target_ulong vtype)
513 {
514     uint8_t sew = FIELD_EX64(vtype, VTYPE, VSEW);
515     int8_t lmul = sextract32(FIELD_EX64(vtype, VTYPE, VLMUL), 0, 3);
516     return cpu->cfg.vlen >> (sew + 3 - lmul);
517 }
518 
519 void cpu_get_tb_cpu_state(CPURISCVState *env, target_ulong *pc,
520                           target_ulong *cs_base, uint32_t *pflags);
521 
522 void riscv_cpu_update_mask(CPURISCVState *env);
523 
524 RISCVException riscv_csrrw(CPURISCVState *env, int csrno,
525                            target_ulong *ret_value,
526                            target_ulong new_value, target_ulong write_mask);
527 RISCVException riscv_csrrw_debug(CPURISCVState *env, int csrno,
528                                  target_ulong *ret_value,
529                                  target_ulong new_value,
530                                  target_ulong write_mask);
531 
532 static inline void riscv_csr_write(CPURISCVState *env, int csrno,
533                                    target_ulong val)
534 {
535     riscv_csrrw(env, csrno, NULL, val, MAKE_64BIT_MASK(0, TARGET_LONG_BITS));
536 }
537 
538 static inline target_ulong riscv_csr_read(CPURISCVState *env, int csrno)
539 {
540     target_ulong val = 0;
541     riscv_csrrw(env, csrno, &val, 0, 0);
542     return val;
543 }
544 
545 typedef RISCVException (*riscv_csr_predicate_fn)(CPURISCVState *env,
546                                                  int csrno);
547 typedef RISCVException (*riscv_csr_read_fn)(CPURISCVState *env, int csrno,
548                                             target_ulong *ret_value);
549 typedef RISCVException (*riscv_csr_write_fn)(CPURISCVState *env, int csrno,
550                                              target_ulong new_value);
551 typedef RISCVException (*riscv_csr_op_fn)(CPURISCVState *env, int csrno,
552                                           target_ulong *ret_value,
553                                           target_ulong new_value,
554                                           target_ulong write_mask);
555 
556 RISCVException riscv_csrrw_i128(CPURISCVState *env, int csrno,
557                                 Int128 *ret_value,
558                                 Int128 new_value, Int128 write_mask);
559 
560 typedef RISCVException (*riscv_csr_read128_fn)(CPURISCVState *env, int csrno,
561                                                Int128 *ret_value);
562 typedef RISCVException (*riscv_csr_write128_fn)(CPURISCVState *env, int csrno,
563                                              Int128 new_value);
564 
565 typedef struct {
566     const char *name;
567     riscv_csr_predicate_fn predicate;
568     riscv_csr_read_fn read;
569     riscv_csr_write_fn write;
570     riscv_csr_op_fn op;
571     riscv_csr_read128_fn read128;
572     riscv_csr_write128_fn write128;
573 } riscv_csr_operations;
574 
575 /* CSR function table constants */
576 enum {
577     CSR_TABLE_SIZE = 0x1000
578 };
579 
580 /* CSR function table */
581 extern riscv_csr_operations csr_ops[CSR_TABLE_SIZE];
582 
583 void riscv_get_csr_ops(int csrno, riscv_csr_operations *ops);
584 void riscv_set_csr_ops(int csrno, riscv_csr_operations *ops);
585 
586 void riscv_cpu_register_gdb_regs_for_features(CPUState *cs);
587 
588 #endif /* RISCV_CPU_H */
589