xref: /openbmc/qemu/target/riscv/cpu.h (revision 10f1ca27)
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 
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 
150     /* 128-bit helpers upper part return value */
151     target_ulong retxh;
152 
153     uint32_t features;
154 
155 #ifdef CONFIG_USER_ONLY
156     uint32_t elf_flags;
157 #endif
158 
159 #ifndef CONFIG_USER_ONLY
160     target_ulong priv;
161     /* This contains QEMU specific information about the virt state. */
162     target_ulong virt;
163     target_ulong resetvec;
164 
165     target_ulong mhartid;
166     /*
167      * For RV32 this is 32-bit mstatus and 32-bit mstatush.
168      * For RV64 this is a 64-bit mstatus.
169      */
170     uint64_t mstatus;
171 
172     target_ulong mip;
173 
174     uint32_t miclaim;
175 
176     target_ulong mie;
177     target_ulong mideleg;
178 
179     target_ulong satp;   /* since: priv-1.10.0 */
180     target_ulong stval;
181     target_ulong medeleg;
182 
183     target_ulong stvec;
184     target_ulong sepc;
185     target_ulong scause;
186 
187     target_ulong mtvec;
188     target_ulong mepc;
189     target_ulong mcause;
190     target_ulong mtval;  /* since: priv-1.10.0 */
191 
192     /* Hypervisor CSRs */
193     target_ulong hstatus;
194     target_ulong hedeleg;
195     target_ulong hideleg;
196     target_ulong hcounteren;
197     target_ulong htval;
198     target_ulong htinst;
199     target_ulong hgatp;
200     uint64_t htimedelta;
201 
202     /* Upper 64-bits of 128-bit CSRs */
203     uint64_t mscratchh;
204     uint64_t sscratchh;
205 
206     /* Virtual CSRs */
207     /*
208      * For RV32 this is 32-bit vsstatus and 32-bit vsstatush.
209      * For RV64 this is a 64-bit vsstatus.
210      */
211     uint64_t vsstatus;
212     target_ulong vstvec;
213     target_ulong vsscratch;
214     target_ulong vsepc;
215     target_ulong vscause;
216     target_ulong vstval;
217     target_ulong vsatp;
218 
219     target_ulong mtval2;
220     target_ulong mtinst;
221 
222     /* HS Backup CSRs */
223     target_ulong stvec_hs;
224     target_ulong sscratch_hs;
225     target_ulong sepc_hs;
226     target_ulong scause_hs;
227     target_ulong stval_hs;
228     target_ulong satp_hs;
229     uint64_t mstatus_hs;
230 
231     /* Signals whether the current exception occurred with two-stage address
232        translation active. */
233     bool two_stage_lookup;
234 
235     target_ulong scounteren;
236     target_ulong mcounteren;
237 
238     target_ulong sscratch;
239     target_ulong mscratch;
240 
241     /* temporary htif regs */
242     uint64_t mfromhost;
243     uint64_t mtohost;
244     uint64_t timecmp;
245 
246     /* physical memory protection */
247     pmp_table_t pmp_state;
248     target_ulong mseccfg;
249 
250     /* machine specific rdtime callback */
251     uint64_t (*rdtime_fn)(uint32_t);
252     uint32_t rdtime_fn_arg;
253 
254     /* True if in debugger mode.  */
255     bool debugger;
256 
257     /*
258      * CSRs for PointerMasking extension
259      */
260     target_ulong mmte;
261     target_ulong mpmmask;
262     target_ulong mpmbase;
263     target_ulong spmmask;
264     target_ulong spmbase;
265     target_ulong upmmask;
266     target_ulong upmbase;
267 #endif
268 
269     float_status fp_status;
270 
271     /* Fields from here on are preserved across CPU reset. */
272     QEMUTimer *timer; /* Internal timer */
273 
274     hwaddr kernel_addr;
275     hwaddr fdt_addr;
276 };
277 
278 OBJECT_DECLARE_TYPE(RISCVCPU, RISCVCPUClass,
279                     RISCV_CPU)
280 
281 /**
282  * RISCVCPUClass:
283  * @parent_realize: The parent class' realize handler.
284  * @parent_reset: The parent class' reset handler.
285  *
286  * A RISCV CPU model.
287  */
288 struct RISCVCPUClass {
289     /*< private >*/
290     CPUClass parent_class;
291     /*< public >*/
292     DeviceRealize parent_realize;
293     DeviceReset parent_reset;
294 };
295 
296 /**
297  * RISCVCPU:
298  * @env: #CPURISCVState
299  *
300  * A RISCV CPU.
301  */
302 struct RISCVCPU {
303     /*< private >*/
304     CPUState parent_obj;
305     /*< public >*/
306     CPUNegativeOffsetState neg;
307     CPURISCVState env;
308 
309     char *dyn_csr_xml;
310     char *dyn_vreg_xml;
311 
312     /* Configuration Settings */
313     struct {
314         bool ext_i;
315         bool ext_e;
316         bool ext_g;
317         bool ext_m;
318         bool ext_a;
319         bool ext_f;
320         bool ext_d;
321         bool ext_c;
322         bool ext_s;
323         bool ext_u;
324         bool ext_h;
325         bool ext_j;
326         bool ext_v;
327         bool ext_zba;
328         bool ext_zbb;
329         bool ext_zbc;
330         bool ext_zbs;
331         bool ext_counters;
332         bool ext_ifencei;
333         bool ext_icsr;
334         bool ext_zfh;
335         bool ext_zfhmin;
336 
337         char *priv_spec;
338         char *user_spec;
339         char *bext_spec;
340         char *vext_spec;
341         uint16_t vlen;
342         uint16_t elen;
343         bool mmu;
344         bool pmp;
345         bool epmp;
346         uint64_t resetvec;
347     } cfg;
348 };
349 
350 static inline int riscv_has_ext(CPURISCVState *env, target_ulong ext)
351 {
352     return (env->misa_ext & ext) != 0;
353 }
354 
355 static inline bool riscv_feature(CPURISCVState *env, int feature)
356 {
357     return env->features & (1ULL << feature);
358 }
359 
360 #include "cpu_user.h"
361 
362 extern const char * const riscv_int_regnames[];
363 extern const char * const riscv_int_regnamesh[];
364 extern const char * const riscv_fpr_regnames[];
365 
366 const char *riscv_cpu_get_trap_name(target_ulong cause, bool async);
367 void riscv_cpu_do_interrupt(CPUState *cpu);
368 int riscv_cpu_write_elf64_note(WriteCoreDumpFunction f, CPUState *cs,
369                                int cpuid, void *opaque);
370 int riscv_cpu_write_elf32_note(WriteCoreDumpFunction f, CPUState *cs,
371                                int cpuid, void *opaque);
372 int riscv_cpu_gdb_read_register(CPUState *cpu, GByteArray *buf, int reg);
373 int riscv_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);
374 bool riscv_cpu_fp_enabled(CPURISCVState *env);
375 bool riscv_cpu_vector_enabled(CPURISCVState *env);
376 bool riscv_cpu_virt_enabled(CPURISCVState *env);
377 void riscv_cpu_set_virt_enabled(CPURISCVState *env, bool enable);
378 bool riscv_cpu_two_stage_lookup(int mmu_idx);
379 int riscv_cpu_mmu_index(CPURISCVState *env, bool ifetch);
380 hwaddr riscv_cpu_get_phys_page_debug(CPUState *cpu, vaddr addr);
381 void  riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
382                                     MMUAccessType access_type, int mmu_idx,
383                                     uintptr_t retaddr) QEMU_NORETURN;
384 bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
385                         MMUAccessType access_type, int mmu_idx,
386                         bool probe, uintptr_t retaddr);
387 void riscv_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr,
388                                      vaddr addr, unsigned size,
389                                      MMUAccessType access_type,
390                                      int mmu_idx, MemTxAttrs attrs,
391                                      MemTxResult response, uintptr_t retaddr);
392 char *riscv_isa_string(RISCVCPU *cpu);
393 void riscv_cpu_list(void);
394 
395 #define cpu_list riscv_cpu_list
396 #define cpu_mmu_index riscv_cpu_mmu_index
397 
398 #ifndef CONFIG_USER_ONLY
399 bool riscv_cpu_exec_interrupt(CPUState *cs, int interrupt_request);
400 void riscv_cpu_swap_hypervisor_regs(CPURISCVState *env);
401 int riscv_cpu_claim_interrupts(RISCVCPU *cpu, uint32_t interrupts);
402 uint32_t riscv_cpu_update_mip(RISCVCPU *cpu, uint32_t mask, uint32_t value);
403 #define BOOL_TO_MASK(x) (-!!(x)) /* helper for riscv_cpu_update_mip value */
404 void riscv_cpu_set_rdtime_fn(CPURISCVState *env, uint64_t (*fn)(uint32_t),
405                              uint32_t arg);
406 #endif
407 void riscv_cpu_set_mode(CPURISCVState *env, target_ulong newpriv);
408 
409 void riscv_translate_init(void);
410 void QEMU_NORETURN riscv_raise_exception(CPURISCVState *env,
411                                          uint32_t exception, uintptr_t pc);
412 
413 target_ulong riscv_cpu_get_fflags(CPURISCVState *env);
414 void riscv_cpu_set_fflags(CPURISCVState *env, target_ulong);
415 
416 #define TB_FLAGS_PRIV_MMU_MASK                3
417 #define TB_FLAGS_PRIV_HYP_ACCESS_MASK   (1 << 2)
418 #define TB_FLAGS_MSTATUS_FS MSTATUS_FS
419 #define TB_FLAGS_MSTATUS_VS MSTATUS_VS
420 
421 typedef CPURISCVState CPUArchState;
422 typedef RISCVCPU ArchCPU;
423 #include "exec/cpu-all.h"
424 
425 FIELD(TB_FLAGS, MEM_IDX, 0, 3)
426 FIELD(TB_FLAGS, LMUL, 3, 3)
427 FIELD(TB_FLAGS, SEW, 6, 3)
428 /* Skip MSTATUS_VS (0x600) bits */
429 FIELD(TB_FLAGS, VL_EQ_VLMAX, 11, 1)
430 FIELD(TB_FLAGS, VILL, 12, 1)
431 /* Skip MSTATUS_FS (0x6000) bits */
432 /* Is a Hypervisor instruction load/store allowed? */
433 FIELD(TB_FLAGS, HLSX, 15, 1)
434 FIELD(TB_FLAGS, MSTATUS_HS_FS, 16, 2)
435 FIELD(TB_FLAGS, MSTATUS_HS_VS, 18, 2)
436 /* The combination of MXL/SXL/UXL that applies to the current cpu mode. */
437 FIELD(TB_FLAGS, XL, 20, 2)
438 /* If PointerMasking should be applied */
439 FIELD(TB_FLAGS, PM_ENABLED, 22, 1)
440 
441 #ifdef TARGET_RISCV32
442 #define riscv_cpu_mxl(env)  ((void)(env), MXL_RV32)
443 #else
444 static inline RISCVMXL riscv_cpu_mxl(CPURISCVState *env)
445 {
446     return env->misa_mxl;
447 }
448 #endif
449 
450 /*
451  * Encode LMUL to lmul as follows:
452  *     LMUL    vlmul    lmul
453  *      1       000       0
454  *      2       001       1
455  *      4       010       2
456  *      8       011       3
457  *      -       100       -
458  *     1/8      101      -3
459  *     1/4      110      -2
460  *     1/2      111      -1
461  *
462  * then, we can calculate VLMAX = vlen >> (vsew + 3 - lmul)
463  * e.g. vlen = 256 bits, SEW = 16, LMUL = 1/8
464  *      => VLMAX = vlen >> (1 + 3 - (-3))
465  *               = 256 >> 7
466  *               = 2
467  */
468 static inline uint32_t vext_get_vlmax(RISCVCPU *cpu, target_ulong vtype)
469 {
470     uint8_t sew = FIELD_EX64(vtype, VTYPE, VSEW);
471     int8_t lmul = sextract32(FIELD_EX64(vtype, VTYPE, VLMUL), 0, 3);
472     return cpu->cfg.vlen >> (sew + 3 - lmul);
473 }
474 
475 void cpu_get_tb_cpu_state(CPURISCVState *env, target_ulong *pc,
476                           target_ulong *cs_base, uint32_t *pflags);
477 
478 RISCVException riscv_csrrw(CPURISCVState *env, int csrno,
479                            target_ulong *ret_value,
480                            target_ulong new_value, target_ulong write_mask);
481 RISCVException riscv_csrrw_debug(CPURISCVState *env, int csrno,
482                                  target_ulong *ret_value,
483                                  target_ulong new_value,
484                                  target_ulong write_mask);
485 
486 static inline void riscv_csr_write(CPURISCVState *env, int csrno,
487                                    target_ulong val)
488 {
489     riscv_csrrw(env, csrno, NULL, val, MAKE_64BIT_MASK(0, TARGET_LONG_BITS));
490 }
491 
492 static inline target_ulong riscv_csr_read(CPURISCVState *env, int csrno)
493 {
494     target_ulong val = 0;
495     riscv_csrrw(env, csrno, &val, 0, 0);
496     return val;
497 }
498 
499 typedef RISCVException (*riscv_csr_predicate_fn)(CPURISCVState *env,
500                                                  int csrno);
501 typedef RISCVException (*riscv_csr_read_fn)(CPURISCVState *env, int csrno,
502                                             target_ulong *ret_value);
503 typedef RISCVException (*riscv_csr_write_fn)(CPURISCVState *env, int csrno,
504                                              target_ulong new_value);
505 typedef RISCVException (*riscv_csr_op_fn)(CPURISCVState *env, int csrno,
506                                           target_ulong *ret_value,
507                                           target_ulong new_value,
508                                           target_ulong write_mask);
509 
510 RISCVException riscv_csrrw_i128(CPURISCVState *env, int csrno,
511                                 Int128 *ret_value,
512                                 Int128 new_value, Int128 write_mask);
513 
514 typedef RISCVException (*riscv_csr_read128_fn)(CPURISCVState *env, int csrno,
515                                                Int128 *ret_value);
516 typedef RISCVException (*riscv_csr_write128_fn)(CPURISCVState *env, int csrno,
517                                              Int128 new_value);
518 
519 typedef struct {
520     const char *name;
521     riscv_csr_predicate_fn predicate;
522     riscv_csr_read_fn read;
523     riscv_csr_write_fn write;
524     riscv_csr_op_fn op;
525     riscv_csr_read128_fn read128;
526     riscv_csr_write128_fn write128;
527 } riscv_csr_operations;
528 
529 /* CSR function table constants */
530 enum {
531     CSR_TABLE_SIZE = 0x1000
532 };
533 
534 /* CSR function table */
535 extern riscv_csr_operations csr_ops[CSR_TABLE_SIZE];
536 
537 void riscv_get_csr_ops(int csrno, riscv_csr_operations *ops);
538 void riscv_set_csr_ops(int csrno, riscv_csr_operations *ops);
539 
540 void riscv_cpu_register_gdb_regs_for_features(CPUState *cs);
541 
542 #endif /* RISCV_CPU_H */
543