xref: /openbmc/qemu/target/riscv/cpu.h (revision 457c360f)
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     target_ulong guest_phys_fault_addr;
136 
137     target_ulong priv_ver;
138     target_ulong bext_ver;
139     target_ulong vext_ver;
140 
141     /* RISCVMXL, but uint32_t for vmstate migration */
142     uint32_t misa_mxl;      /* current mxl */
143     uint32_t misa_mxl_max;  /* max mxl for this cpu */
144     uint32_t misa_ext;      /* current extensions */
145     uint32_t misa_ext_mask; /* max ext for this cpu */
146 
147     /* 128-bit helpers upper part return value */
148     target_ulong retxh;
149 
150     uint32_t features;
151 
152 #ifdef CONFIG_USER_ONLY
153     uint32_t elf_flags;
154 #endif
155 
156 #ifndef CONFIG_USER_ONLY
157     target_ulong priv;
158     /* This contains QEMU specific information about the virt state. */
159     target_ulong virt;
160     target_ulong resetvec;
161 
162     target_ulong mhartid;
163     /*
164      * For RV32 this is 32-bit mstatus and 32-bit mstatush.
165      * For RV64 this is a 64-bit mstatus.
166      */
167     uint64_t mstatus;
168 
169     target_ulong mip;
170 
171     uint32_t miclaim;
172 
173     target_ulong mie;
174     target_ulong mideleg;
175 
176     target_ulong satp;   /* since: priv-1.10.0 */
177     target_ulong stval;
178     target_ulong medeleg;
179 
180     target_ulong stvec;
181     target_ulong sepc;
182     target_ulong scause;
183 
184     target_ulong mtvec;
185     target_ulong mepc;
186     target_ulong mcause;
187     target_ulong mtval;  /* since: priv-1.10.0 */
188 
189     /* Hypervisor CSRs */
190     target_ulong hstatus;
191     target_ulong hedeleg;
192     target_ulong hideleg;
193     target_ulong hcounteren;
194     target_ulong htval;
195     target_ulong htinst;
196     target_ulong hgatp;
197     uint64_t htimedelta;
198 
199     /* Upper 64-bits of 128-bit CSRs */
200     uint64_t mscratchh;
201     uint64_t sscratchh;
202 
203     /* Virtual CSRs */
204     /*
205      * For RV32 this is 32-bit vsstatus and 32-bit vsstatush.
206      * For RV64 this is a 64-bit vsstatus.
207      */
208     uint64_t vsstatus;
209     target_ulong vstvec;
210     target_ulong vsscratch;
211     target_ulong vsepc;
212     target_ulong vscause;
213     target_ulong vstval;
214     target_ulong vsatp;
215 
216     target_ulong mtval2;
217     target_ulong mtinst;
218 
219     /* HS Backup CSRs */
220     target_ulong stvec_hs;
221     target_ulong sscratch_hs;
222     target_ulong sepc_hs;
223     target_ulong scause_hs;
224     target_ulong stval_hs;
225     target_ulong satp_hs;
226     uint64_t mstatus_hs;
227 
228     /* Signals whether the current exception occurred with two-stage address
229        translation active. */
230     bool two_stage_lookup;
231 
232     target_ulong scounteren;
233     target_ulong mcounteren;
234 
235     target_ulong sscratch;
236     target_ulong mscratch;
237 
238     /* temporary htif regs */
239     uint64_t mfromhost;
240     uint64_t mtohost;
241     uint64_t timecmp;
242 
243     /* physical memory protection */
244     pmp_table_t pmp_state;
245     target_ulong mseccfg;
246 
247     /* machine specific rdtime callback */
248     uint64_t (*rdtime_fn)(uint32_t);
249     uint32_t rdtime_fn_arg;
250 
251     /* True if in debugger mode.  */
252     bool debugger;
253 
254     /*
255      * CSRs for PointerMasking extension
256      */
257     target_ulong mmte;
258     target_ulong mpmmask;
259     target_ulong mpmbase;
260     target_ulong spmmask;
261     target_ulong spmbase;
262     target_ulong upmmask;
263     target_ulong upmbase;
264 #endif
265 
266     float_status fp_status;
267 
268     /* Fields from here on are preserved across CPU reset. */
269     QEMUTimer *timer; /* Internal timer */
270 };
271 
272 OBJECT_DECLARE_TYPE(RISCVCPU, RISCVCPUClass,
273                     RISCV_CPU)
274 
275 /**
276  * RISCVCPUClass:
277  * @parent_realize: The parent class' realize handler.
278  * @parent_reset: The parent class' reset handler.
279  *
280  * A RISCV CPU model.
281  */
282 struct RISCVCPUClass {
283     /*< private >*/
284     CPUClass parent_class;
285     /*< public >*/
286     DeviceRealize parent_realize;
287     DeviceReset parent_reset;
288 };
289 
290 /**
291  * RISCVCPU:
292  * @env: #CPURISCVState
293  *
294  * A RISCV CPU.
295  */
296 struct RISCVCPU {
297     /*< private >*/
298     CPUState parent_obj;
299     /*< public >*/
300     CPUNegativeOffsetState neg;
301     CPURISCVState env;
302 
303     char *dyn_csr_xml;
304     char *dyn_vreg_xml;
305 
306     /* Configuration Settings */
307     struct {
308         bool ext_i;
309         bool ext_e;
310         bool ext_g;
311         bool ext_m;
312         bool ext_a;
313         bool ext_f;
314         bool ext_d;
315         bool ext_c;
316         bool ext_s;
317         bool ext_u;
318         bool ext_h;
319         bool ext_j;
320         bool ext_v;
321         bool ext_zba;
322         bool ext_zbb;
323         bool ext_zbc;
324         bool ext_zbs;
325         bool ext_counters;
326         bool ext_ifencei;
327         bool ext_icsr;
328         bool ext_zfh;
329         bool ext_zfhmin;
330 
331         char *priv_spec;
332         char *user_spec;
333         char *bext_spec;
334         char *vext_spec;
335         uint16_t vlen;
336         uint16_t elen;
337         bool mmu;
338         bool pmp;
339         bool epmp;
340         uint64_t resetvec;
341     } cfg;
342 };
343 
344 static inline int riscv_has_ext(CPURISCVState *env, target_ulong ext)
345 {
346     return (env->misa_ext & ext) != 0;
347 }
348 
349 static inline bool riscv_feature(CPURISCVState *env, int feature)
350 {
351     return env->features & (1ULL << feature);
352 }
353 
354 #include "cpu_user.h"
355 
356 extern const char * const riscv_int_regnames[];
357 extern const char * const riscv_int_regnamesh[];
358 extern const char * const riscv_fpr_regnames[];
359 
360 const char *riscv_cpu_get_trap_name(target_ulong cause, bool async);
361 void riscv_cpu_do_interrupt(CPUState *cpu);
362 int riscv_cpu_write_elf64_note(WriteCoreDumpFunction f, CPUState *cs,
363                                int cpuid, void *opaque);
364 int riscv_cpu_write_elf32_note(WriteCoreDumpFunction f, CPUState *cs,
365                                int cpuid, void *opaque);
366 int riscv_cpu_gdb_read_register(CPUState *cpu, GByteArray *buf, int reg);
367 int riscv_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);
368 bool riscv_cpu_fp_enabled(CPURISCVState *env);
369 bool riscv_cpu_vector_enabled(CPURISCVState *env);
370 bool riscv_cpu_virt_enabled(CPURISCVState *env);
371 void riscv_cpu_set_virt_enabled(CPURISCVState *env, bool enable);
372 bool riscv_cpu_two_stage_lookup(int mmu_idx);
373 int riscv_cpu_mmu_index(CPURISCVState *env, bool ifetch);
374 hwaddr riscv_cpu_get_phys_page_debug(CPUState *cpu, vaddr addr);
375 void  riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
376                                     MMUAccessType access_type, int mmu_idx,
377                                     uintptr_t retaddr) QEMU_NORETURN;
378 bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
379                         MMUAccessType access_type, int mmu_idx,
380                         bool probe, uintptr_t retaddr);
381 void riscv_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr,
382                                      vaddr addr, unsigned size,
383                                      MMUAccessType access_type,
384                                      int mmu_idx, MemTxAttrs attrs,
385                                      MemTxResult response, uintptr_t retaddr);
386 char *riscv_isa_string(RISCVCPU *cpu);
387 void riscv_cpu_list(void);
388 
389 #define cpu_list riscv_cpu_list
390 #define cpu_mmu_index riscv_cpu_mmu_index
391 
392 #ifndef CONFIG_USER_ONLY
393 bool riscv_cpu_exec_interrupt(CPUState *cs, int interrupt_request);
394 void riscv_cpu_swap_hypervisor_regs(CPURISCVState *env);
395 int riscv_cpu_claim_interrupts(RISCVCPU *cpu, uint32_t interrupts);
396 uint32_t riscv_cpu_update_mip(RISCVCPU *cpu, uint32_t mask, uint32_t value);
397 #define BOOL_TO_MASK(x) (-!!(x)) /* helper for riscv_cpu_update_mip value */
398 void riscv_cpu_set_rdtime_fn(CPURISCVState *env, uint64_t (*fn)(uint32_t),
399                              uint32_t arg);
400 #endif
401 void riscv_cpu_set_mode(CPURISCVState *env, target_ulong newpriv);
402 
403 void riscv_translate_init(void);
404 void QEMU_NORETURN riscv_raise_exception(CPURISCVState *env,
405                                          uint32_t exception, uintptr_t pc);
406 
407 target_ulong riscv_cpu_get_fflags(CPURISCVState *env);
408 void riscv_cpu_set_fflags(CPURISCVState *env, target_ulong);
409 
410 #define TB_FLAGS_PRIV_MMU_MASK                3
411 #define TB_FLAGS_PRIV_HYP_ACCESS_MASK   (1 << 2)
412 #define TB_FLAGS_MSTATUS_FS MSTATUS_FS
413 #define TB_FLAGS_MSTATUS_VS MSTATUS_VS
414 
415 typedef CPURISCVState CPUArchState;
416 typedef RISCVCPU ArchCPU;
417 #include "exec/cpu-all.h"
418 
419 FIELD(TB_FLAGS, MEM_IDX, 0, 3)
420 FIELD(TB_FLAGS, LMUL, 3, 3)
421 FIELD(TB_FLAGS, SEW, 6, 3)
422 /* Skip MSTATUS_VS (0x600) bits */
423 FIELD(TB_FLAGS, VL_EQ_VLMAX, 11, 1)
424 FIELD(TB_FLAGS, VILL, 12, 1)
425 /* Skip MSTATUS_FS (0x6000) bits */
426 /* Is a Hypervisor instruction load/store allowed? */
427 FIELD(TB_FLAGS, HLSX, 15, 1)
428 FIELD(TB_FLAGS, MSTATUS_HS_FS, 16, 2)
429 FIELD(TB_FLAGS, MSTATUS_HS_VS, 18, 2)
430 /* The combination of MXL/SXL/UXL that applies to the current cpu mode. */
431 FIELD(TB_FLAGS, XL, 20, 2)
432 /* If PointerMasking should be applied */
433 FIELD(TB_FLAGS, PM_ENABLED, 22, 1)
434 
435 #ifdef TARGET_RISCV32
436 #define riscv_cpu_mxl(env)  ((void)(env), MXL_RV32)
437 #else
438 static inline RISCVMXL riscv_cpu_mxl(CPURISCVState *env)
439 {
440     return env->misa_mxl;
441 }
442 #endif
443 
444 /*
445  * Encode LMUL to lmul as follows:
446  *     LMUL    vlmul    lmul
447  *      1       000       0
448  *      2       001       1
449  *      4       010       2
450  *      8       011       3
451  *      -       100       -
452  *     1/8      101      -3
453  *     1/4      110      -2
454  *     1/2      111      -1
455  *
456  * then, we can calculate VLMAX = vlen >> (vsew + 3 - lmul)
457  * e.g. vlen = 256 bits, SEW = 16, LMUL = 1/8
458  *      => VLMAX = vlen >> (1 + 3 - (-3))
459  *               = 256 >> 7
460  *               = 2
461  */
462 static inline uint32_t vext_get_vlmax(RISCVCPU *cpu, target_ulong vtype)
463 {
464     uint8_t sew = FIELD_EX64(vtype, VTYPE, VSEW);
465     int8_t lmul = sextract32(FIELD_EX64(vtype, VTYPE, VLMUL), 0, 3);
466     return cpu->cfg.vlen >> (sew + 3 - lmul);
467 }
468 
469 void cpu_get_tb_cpu_state(CPURISCVState *env, target_ulong *pc,
470                           target_ulong *cs_base, uint32_t *pflags);
471 
472 RISCVException riscv_csrrw(CPURISCVState *env, int csrno,
473                            target_ulong *ret_value,
474                            target_ulong new_value, target_ulong write_mask);
475 RISCVException riscv_csrrw_debug(CPURISCVState *env, int csrno,
476                                  target_ulong *ret_value,
477                                  target_ulong new_value,
478                                  target_ulong write_mask);
479 
480 static inline void riscv_csr_write(CPURISCVState *env, int csrno,
481                                    target_ulong val)
482 {
483     riscv_csrrw(env, csrno, NULL, val, MAKE_64BIT_MASK(0, TARGET_LONG_BITS));
484 }
485 
486 static inline target_ulong riscv_csr_read(CPURISCVState *env, int csrno)
487 {
488     target_ulong val = 0;
489     riscv_csrrw(env, csrno, &val, 0, 0);
490     return val;
491 }
492 
493 typedef RISCVException (*riscv_csr_predicate_fn)(CPURISCVState *env,
494                                                  int csrno);
495 typedef RISCVException (*riscv_csr_read_fn)(CPURISCVState *env, int csrno,
496                                             target_ulong *ret_value);
497 typedef RISCVException (*riscv_csr_write_fn)(CPURISCVState *env, int csrno,
498                                              target_ulong new_value);
499 typedef RISCVException (*riscv_csr_op_fn)(CPURISCVState *env, int csrno,
500                                           target_ulong *ret_value,
501                                           target_ulong new_value,
502                                           target_ulong write_mask);
503 
504 RISCVException riscv_csrrw_i128(CPURISCVState *env, int csrno,
505                                 Int128 *ret_value,
506                                 Int128 new_value, Int128 write_mask);
507 
508 typedef RISCVException (*riscv_csr_read128_fn)(CPURISCVState *env, int csrno,
509                                                Int128 *ret_value);
510 typedef RISCVException (*riscv_csr_write128_fn)(CPURISCVState *env, int csrno,
511                                              Int128 new_value);
512 
513 typedef struct {
514     const char *name;
515     riscv_csr_predicate_fn predicate;
516     riscv_csr_read_fn read;
517     riscv_csr_write_fn write;
518     riscv_csr_op_fn op;
519     riscv_csr_read128_fn read128;
520     riscv_csr_write128_fn write128;
521 } riscv_csr_operations;
522 
523 /* CSR function table constants */
524 enum {
525     CSR_TABLE_SIZE = 0x1000
526 };
527 
528 /* CSR function table */
529 extern riscv_csr_operations csr_ops[CSR_TABLE_SIZE];
530 
531 void riscv_get_csr_ops(int csrno, riscv_csr_operations *ops);
532 void riscv_set_csr_ops(int csrno, riscv_csr_operations *ops);
533 
534 void riscv_cpu_register_gdb_regs_for_features(CPUState *cs);
535 
536 #endif /* RISCV_CPU_H */
537