xref: /openbmc/qemu/target/riscv/cpu.h (revision c8cbc952)
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 
51 #if defined(TARGET_RISCV32)
52 # define TYPE_RISCV_CPU_BASE            TYPE_RISCV_CPU_BASE32
53 #elif defined(TARGET_RISCV64)
54 # define TYPE_RISCV_CPU_BASE            TYPE_RISCV_CPU_BASE64
55 #endif
56 
57 #define RV(x) ((target_ulong)1 << (x - 'A'))
58 
59 #define RVI RV('I')
60 #define RVE RV('E') /* E and I are mutually exclusive */
61 #define RVM RV('M')
62 #define RVA RV('A')
63 #define RVF RV('F')
64 #define RVD RV('D')
65 #define RVV RV('V')
66 #define RVC RV('C')
67 #define RVS RV('S')
68 #define RVU RV('U')
69 #define RVH RV('H')
70 #define RVJ RV('J')
71 
72 /* S extension denotes that Supervisor mode exists, however it is possible
73    to have a core that support S mode but does not have an MMU and there
74    is currently no bit in misa to indicate whether an MMU exists or not
75    so a cpu features bitfield is required, likewise for optional PMP support */
76 enum {
77     RISCV_FEATURE_MMU,
78     RISCV_FEATURE_PMP,
79     RISCV_FEATURE_EPMP,
80     RISCV_FEATURE_MISA
81 };
82 
83 #define PRIV_VERSION_1_10_0 0x00011000
84 #define PRIV_VERSION_1_11_0 0x00011100
85 
86 #define VEXT_VERSION_1_00_0 0x00010000
87 
88 enum {
89     TRANSLATE_SUCCESS,
90     TRANSLATE_FAIL,
91     TRANSLATE_PMP_FAIL,
92     TRANSLATE_G_STAGE_FAIL
93 };
94 
95 #define MMU_USER_IDX 3
96 
97 #define MAX_RISCV_PMPS (16)
98 
99 typedef struct CPURISCVState CPURISCVState;
100 
101 #if !defined(CONFIG_USER_ONLY)
102 #include "pmp.h"
103 #endif
104 
105 #define RV_VLEN_MAX 1024
106 
107 FIELD(VTYPE, VLMUL, 0, 3)
108 FIELD(VTYPE, VSEW, 3, 3)
109 FIELD(VTYPE, VTA, 6, 1)
110 FIELD(VTYPE, VMA, 7, 1)
111 FIELD(VTYPE, VEDIV, 8, 2)
112 FIELD(VTYPE, RESERVED, 10, sizeof(target_ulong) * 8 - 11)
113 FIELD(VTYPE, VILL, sizeof(target_ulong) * 8 - 1, 1)
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 
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     uint32_t bins;
136 
137     target_ulong guest_phys_fault_addr;
138 
139     target_ulong priv_ver;
140     target_ulong bext_ver;
141     target_ulong vext_ver;
142 
143     /* RISCVMXL, but uint32_t for vmstate migration */
144     uint32_t misa_mxl;      /* current mxl */
145     uint32_t misa_mxl_max;  /* max mxl for this cpu */
146     uint32_t misa_ext;      /* current extensions */
147     uint32_t misa_ext_mask; /* max ext for this cpu */
148 
149     /* 128-bit helpers upper part return value */
150     target_ulong retxh;
151 
152     uint32_t features;
153 
154 #ifdef CONFIG_USER_ONLY
155     uint32_t elf_flags;
156 #endif
157 
158 #ifndef CONFIG_USER_ONLY
159     target_ulong priv;
160     /* This contains QEMU specific information about the virt state. */
161     target_ulong virt;
162     target_ulong resetvec;
163 
164     target_ulong mhartid;
165     /*
166      * For RV32 this is 32-bit mstatus and 32-bit mstatush.
167      * For RV64 this is a 64-bit mstatus.
168      */
169     uint64_t mstatus;
170 
171     target_ulong mip;
172 
173     uint32_t miclaim;
174 
175     target_ulong mie;
176     target_ulong mideleg;
177 
178     target_ulong satp;   /* since: priv-1.10.0 */
179     target_ulong stval;
180     target_ulong medeleg;
181 
182     target_ulong stvec;
183     target_ulong sepc;
184     target_ulong scause;
185 
186     target_ulong mtvec;
187     target_ulong mepc;
188     target_ulong mcause;
189     target_ulong mtval;  /* since: priv-1.10.0 */
190 
191     /* Hypervisor CSRs */
192     target_ulong hstatus;
193     target_ulong hedeleg;
194     target_ulong hideleg;
195     target_ulong hcounteren;
196     target_ulong htval;
197     target_ulong htinst;
198     target_ulong hgatp;
199     uint64_t htimedelta;
200 
201     /* Upper 64-bits of 128-bit CSRs */
202     uint64_t mscratchh;
203     uint64_t sscratchh;
204 
205     /* Virtual CSRs */
206     /*
207      * For RV32 this is 32-bit vsstatus and 32-bit vsstatush.
208      * For RV64 this is a 64-bit vsstatus.
209      */
210     uint64_t vsstatus;
211     target_ulong vstvec;
212     target_ulong vsscratch;
213     target_ulong vsepc;
214     target_ulong vscause;
215     target_ulong vstval;
216     target_ulong vsatp;
217 
218     target_ulong mtval2;
219     target_ulong mtinst;
220 
221     /* HS Backup CSRs */
222     target_ulong stvec_hs;
223     target_ulong sscratch_hs;
224     target_ulong sepc_hs;
225     target_ulong scause_hs;
226     target_ulong stval_hs;
227     target_ulong satp_hs;
228     uint64_t mstatus_hs;
229 
230     /* Signals whether the current exception occurred with two-stage address
231        translation active. */
232     bool two_stage_lookup;
233 
234     target_ulong scounteren;
235     target_ulong mcounteren;
236 
237     target_ulong sscratch;
238     target_ulong mscratch;
239 
240     /* temporary htif regs */
241     uint64_t mfromhost;
242     uint64_t mtohost;
243     uint64_t timecmp;
244 
245     /* physical memory protection */
246     pmp_table_t pmp_state;
247     target_ulong mseccfg;
248 
249     /* machine specific rdtime callback */
250     uint64_t (*rdtime_fn)(uint32_t);
251     uint32_t rdtime_fn_arg;
252 
253     /* True if in debugger mode.  */
254     bool debugger;
255 
256     /*
257      * CSRs for PointerMasking extension
258      */
259     target_ulong mmte;
260     target_ulong mpmmask;
261     target_ulong mpmbase;
262     target_ulong spmmask;
263     target_ulong spmbase;
264     target_ulong upmmask;
265     target_ulong upmbase;
266 #endif
267 
268     float_status fp_status;
269 
270     /* Fields from here on are preserved across CPU reset. */
271     QEMUTimer *timer; /* Internal timer */
272 };
273 
274 OBJECT_DECLARE_TYPE(RISCVCPU, RISCVCPUClass,
275                     RISCV_CPU)
276 
277 /**
278  * RISCVCPUClass:
279  * @parent_realize: The parent class' realize handler.
280  * @parent_reset: The parent class' reset handler.
281  *
282  * A RISCV CPU model.
283  */
284 struct RISCVCPUClass {
285     /*< private >*/
286     CPUClass parent_class;
287     /*< public >*/
288     DeviceRealize parent_realize;
289     DeviceReset parent_reset;
290 };
291 
292 /**
293  * RISCVCPU:
294  * @env: #CPURISCVState
295  *
296  * A RISCV CPU.
297  */
298 struct RISCVCPU {
299     /*< private >*/
300     CPUState parent_obj;
301     /*< public >*/
302     CPUNegativeOffsetState neg;
303     CPURISCVState env;
304 
305     char *dyn_csr_xml;
306     char *dyn_vreg_xml;
307 
308     /* Configuration Settings */
309     struct {
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 
333         char *priv_spec;
334         char *user_spec;
335         char *bext_spec;
336         char *vext_spec;
337         uint16_t vlen;
338         uint16_t elen;
339         bool mmu;
340         bool pmp;
341         bool epmp;
342         uint64_t resetvec;
343     } cfg;
344 };
345 
346 static inline int riscv_has_ext(CPURISCVState *env, target_ulong ext)
347 {
348     return (env->misa_ext & ext) != 0;
349 }
350 
351 static inline bool riscv_feature(CPURISCVState *env, int feature)
352 {
353     return env->features & (1ULL << feature);
354 }
355 
356 #include "cpu_user.h"
357 
358 extern const char * const riscv_int_regnames[];
359 extern const char * const riscv_int_regnamesh[];
360 extern const char * const riscv_fpr_regnames[];
361 
362 const char *riscv_cpu_get_trap_name(target_ulong cause, bool async);
363 void riscv_cpu_do_interrupt(CPUState *cpu);
364 int riscv_cpu_write_elf64_note(WriteCoreDumpFunction f, CPUState *cs,
365                                int cpuid, void *opaque);
366 int riscv_cpu_write_elf32_note(WriteCoreDumpFunction f, CPUState *cs,
367                                int cpuid, void *opaque);
368 int riscv_cpu_gdb_read_register(CPUState *cpu, GByteArray *buf, int reg);
369 int riscv_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);
370 bool riscv_cpu_fp_enabled(CPURISCVState *env);
371 bool riscv_cpu_vector_enabled(CPURISCVState *env);
372 bool riscv_cpu_virt_enabled(CPURISCVState *env);
373 void riscv_cpu_set_virt_enabled(CPURISCVState *env, bool enable);
374 bool riscv_cpu_two_stage_lookup(int mmu_idx);
375 int riscv_cpu_mmu_index(CPURISCVState *env, bool ifetch);
376 hwaddr riscv_cpu_get_phys_page_debug(CPUState *cpu, vaddr addr);
377 void  riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
378                                     MMUAccessType access_type, int mmu_idx,
379                                     uintptr_t retaddr) QEMU_NORETURN;
380 bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
381                         MMUAccessType access_type, int mmu_idx,
382                         bool probe, uintptr_t retaddr);
383 void riscv_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr,
384                                      vaddr addr, unsigned size,
385                                      MMUAccessType access_type,
386                                      int mmu_idx, MemTxAttrs attrs,
387                                      MemTxResult response, uintptr_t retaddr);
388 char *riscv_isa_string(RISCVCPU *cpu);
389 void riscv_cpu_list(void);
390 
391 #define cpu_list riscv_cpu_list
392 #define cpu_mmu_index riscv_cpu_mmu_index
393 
394 #ifndef CONFIG_USER_ONLY
395 bool riscv_cpu_exec_interrupt(CPUState *cs, int interrupt_request);
396 void riscv_cpu_swap_hypervisor_regs(CPURISCVState *env);
397 int riscv_cpu_claim_interrupts(RISCVCPU *cpu, uint32_t interrupts);
398 uint32_t riscv_cpu_update_mip(RISCVCPU *cpu, uint32_t mask, uint32_t value);
399 #define BOOL_TO_MASK(x) (-!!(x)) /* helper for riscv_cpu_update_mip value */
400 void riscv_cpu_set_rdtime_fn(CPURISCVState *env, uint64_t (*fn)(uint32_t),
401                              uint32_t arg);
402 #endif
403 void riscv_cpu_set_mode(CPURISCVState *env, target_ulong newpriv);
404 
405 void riscv_translate_init(void);
406 void QEMU_NORETURN riscv_raise_exception(CPURISCVState *env,
407                                          uint32_t exception, uintptr_t pc);
408 
409 target_ulong riscv_cpu_get_fflags(CPURISCVState *env);
410 void riscv_cpu_set_fflags(CPURISCVState *env, target_ulong);
411 
412 #define TB_FLAGS_PRIV_MMU_MASK                3
413 #define TB_FLAGS_PRIV_HYP_ACCESS_MASK   (1 << 2)
414 #define TB_FLAGS_MSTATUS_FS MSTATUS_FS
415 #define TB_FLAGS_MSTATUS_VS MSTATUS_VS
416 
417 typedef CPURISCVState CPUArchState;
418 typedef RISCVCPU ArchCPU;
419 #include "exec/cpu-all.h"
420 
421 FIELD(TB_FLAGS, MEM_IDX, 0, 3)
422 FIELD(TB_FLAGS, LMUL, 3, 3)
423 FIELD(TB_FLAGS, SEW, 6, 3)
424 /* Skip MSTATUS_VS (0x600) bits */
425 FIELD(TB_FLAGS, VL_EQ_VLMAX, 11, 1)
426 FIELD(TB_FLAGS, VILL, 12, 1)
427 /* Skip MSTATUS_FS (0x6000) bits */
428 /* Is a Hypervisor instruction load/store allowed? */
429 FIELD(TB_FLAGS, HLSX, 15, 1)
430 FIELD(TB_FLAGS, MSTATUS_HS_FS, 16, 2)
431 FIELD(TB_FLAGS, MSTATUS_HS_VS, 18, 2)
432 /* The combination of MXL/SXL/UXL that applies to the current cpu mode. */
433 FIELD(TB_FLAGS, XL, 20, 2)
434 /* If PointerMasking should be applied */
435 FIELD(TB_FLAGS, PM_ENABLED, 22, 1)
436 
437 #ifdef TARGET_RISCV32
438 #define riscv_cpu_mxl(env)  ((void)(env), MXL_RV32)
439 #else
440 static inline RISCVMXL riscv_cpu_mxl(CPURISCVState *env)
441 {
442     return env->misa_mxl;
443 }
444 #endif
445 
446 /*
447  * Encode LMUL to lmul as follows:
448  *     LMUL    vlmul    lmul
449  *      1       000       0
450  *      2       001       1
451  *      4       010       2
452  *      8       011       3
453  *      -       100       -
454  *     1/8      101      -3
455  *     1/4      110      -2
456  *     1/2      111      -1
457  *
458  * then, we can calculate VLMAX = vlen >> (vsew + 3 - lmul)
459  * e.g. vlen = 256 bits, SEW = 16, LMUL = 1/8
460  *      => VLMAX = vlen >> (1 + 3 - (-3))
461  *               = 256 >> 7
462  *               = 2
463  */
464 static inline uint32_t vext_get_vlmax(RISCVCPU *cpu, target_ulong vtype)
465 {
466     uint8_t sew = FIELD_EX64(vtype, VTYPE, VSEW);
467     int8_t lmul = sextract32(FIELD_EX64(vtype, VTYPE, VLMUL), 0, 3);
468     return cpu->cfg.vlen >> (sew + 3 - lmul);
469 }
470 
471 void cpu_get_tb_cpu_state(CPURISCVState *env, target_ulong *pc,
472                           target_ulong *cs_base, uint32_t *pflags);
473 
474 RISCVException riscv_csrrw(CPURISCVState *env, int csrno,
475                            target_ulong *ret_value,
476                            target_ulong new_value, target_ulong write_mask);
477 RISCVException riscv_csrrw_debug(CPURISCVState *env, int csrno,
478                                  target_ulong *ret_value,
479                                  target_ulong new_value,
480                                  target_ulong write_mask);
481 
482 static inline void riscv_csr_write(CPURISCVState *env, int csrno,
483                                    target_ulong val)
484 {
485     riscv_csrrw(env, csrno, NULL, val, MAKE_64BIT_MASK(0, TARGET_LONG_BITS));
486 }
487 
488 static inline target_ulong riscv_csr_read(CPURISCVState *env, int csrno)
489 {
490     target_ulong val = 0;
491     riscv_csrrw(env, csrno, &val, 0, 0);
492     return val;
493 }
494 
495 typedef RISCVException (*riscv_csr_predicate_fn)(CPURISCVState *env,
496                                                  int csrno);
497 typedef RISCVException (*riscv_csr_read_fn)(CPURISCVState *env, int csrno,
498                                             target_ulong *ret_value);
499 typedef RISCVException (*riscv_csr_write_fn)(CPURISCVState *env, int csrno,
500                                              target_ulong new_value);
501 typedef RISCVException (*riscv_csr_op_fn)(CPURISCVState *env, int csrno,
502                                           target_ulong *ret_value,
503                                           target_ulong new_value,
504                                           target_ulong write_mask);
505 
506 RISCVException riscv_csrrw_i128(CPURISCVState *env, int csrno,
507                                 Int128 *ret_value,
508                                 Int128 new_value, Int128 write_mask);
509 
510 typedef RISCVException (*riscv_csr_read128_fn)(CPURISCVState *env, int csrno,
511                                                Int128 *ret_value);
512 typedef RISCVException (*riscv_csr_write128_fn)(CPURISCVState *env, int csrno,
513                                              Int128 new_value);
514 
515 typedef struct {
516     const char *name;
517     riscv_csr_predicate_fn predicate;
518     riscv_csr_read_fn read;
519     riscv_csr_write_fn write;
520     riscv_csr_op_fn op;
521     riscv_csr_read128_fn read128;
522     riscv_csr_write128_fn write128;
523 } riscv_csr_operations;
524 
525 /* CSR function table constants */
526 enum {
527     CSR_TABLE_SIZE = 0x1000
528 };
529 
530 /* CSR function table */
531 extern riscv_csr_operations csr_ops[CSR_TABLE_SIZE];
532 
533 void riscv_get_csr_ops(int csrno, riscv_csr_operations *ops);
534 void riscv_set_csr_ops(int csrno, riscv_csr_operations *ops);
535 
536 void riscv_cpu_register_gdb_regs_for_features(CPUState *cs);
537 
538 #endif /* RISCV_CPU_H */
539