xref: /openbmc/qemu/target/riscv/cpu.h (revision b3a5d1fb)
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 "cpu_bits.h"
29 
30 #define TCG_GUEST_DEFAULT_MO 0
31 
32 #define TYPE_RISCV_CPU "riscv-cpu"
33 
34 #define RISCV_CPU_TYPE_SUFFIX "-" TYPE_RISCV_CPU
35 #define RISCV_CPU_TYPE_NAME(name) (name RISCV_CPU_TYPE_SUFFIX)
36 #define CPU_RESOLVING_TYPE TYPE_RISCV_CPU
37 
38 #define TYPE_RISCV_CPU_ANY              RISCV_CPU_TYPE_NAME("any")
39 #define TYPE_RISCV_CPU_BASE32           RISCV_CPU_TYPE_NAME("rv32")
40 #define TYPE_RISCV_CPU_BASE64           RISCV_CPU_TYPE_NAME("rv64")
41 #define TYPE_RISCV_CPU_BASE128          RISCV_CPU_TYPE_NAME("x-rv128")
42 #define TYPE_RISCV_CPU_IBEX             RISCV_CPU_TYPE_NAME("lowrisc-ibex")
43 #define TYPE_RISCV_CPU_SHAKTI_C         RISCV_CPU_TYPE_NAME("shakti-c")
44 #define TYPE_RISCV_CPU_SIFIVE_E31       RISCV_CPU_TYPE_NAME("sifive-e31")
45 #define TYPE_RISCV_CPU_SIFIVE_E34       RISCV_CPU_TYPE_NAME("sifive-e34")
46 #define TYPE_RISCV_CPU_SIFIVE_E51       RISCV_CPU_TYPE_NAME("sifive-e51")
47 #define TYPE_RISCV_CPU_SIFIVE_U34       RISCV_CPU_TYPE_NAME("sifive-u34")
48 #define TYPE_RISCV_CPU_SIFIVE_U54       RISCV_CPU_TYPE_NAME("sifive-u54")
49 
50 #if defined(TARGET_RISCV32)
51 # define TYPE_RISCV_CPU_BASE            TYPE_RISCV_CPU_BASE32
52 #elif defined(TARGET_RISCV64)
53 # define TYPE_RISCV_CPU_BASE            TYPE_RISCV_CPU_BASE64
54 #endif
55 
56 #define RV(x) ((target_ulong)1 << (x - 'A'))
57 
58 #define RVI RV('I')
59 #define RVE RV('E') /* E and I are mutually exclusive */
60 #define RVM RV('M')
61 #define RVA RV('A')
62 #define RVF RV('F')
63 #define RVD RV('D')
64 #define RVV RV('V')
65 #define RVC RV('C')
66 #define RVS RV('S')
67 #define RVU RV('U')
68 #define RVH RV('H')
69 #define RVJ RV('J')
70 
71 /* S extension denotes that Supervisor mode exists, however it is possible
72    to have a core that support S mode but does not have an MMU and there
73    is currently no bit in misa to indicate whether an MMU exists or not
74    so a cpu features bitfield is required, likewise for optional PMP support */
75 enum {
76     RISCV_FEATURE_MMU,
77     RISCV_FEATURE_PMP,
78     RISCV_FEATURE_EPMP,
79     RISCV_FEATURE_MISA
80 };
81 
82 #define PRIV_VERSION_1_10_0 0x00011000
83 #define PRIV_VERSION_1_11_0 0x00011100
84 
85 #define VEXT_VERSION_1_00_0 0x00010000
86 
87 enum {
88     TRANSLATE_SUCCESS,
89     TRANSLATE_FAIL,
90     TRANSLATE_PMP_FAIL,
91     TRANSLATE_G_STAGE_FAIL
92 };
93 
94 #define MMU_USER_IDX 3
95 
96 #define MAX_RISCV_PMPS (16)
97 
98 typedef struct CPURISCVState CPURISCVState;
99 
100 #if !defined(CONFIG_USER_ONLY)
101 #include "pmp.h"
102 #endif
103 
104 #define RV_VLEN_MAX 1024
105 
106 FIELD(VTYPE, VLMUL, 0, 3)
107 FIELD(VTYPE, VSEW, 3, 3)
108 FIELD(VTYPE, VTA, 6, 1)
109 FIELD(VTYPE, VMA, 7, 1)
110 FIELD(VTYPE, VEDIV, 8, 2)
111 FIELD(VTYPE, RESERVED, 10, sizeof(target_ulong) * 8 - 11)
112 FIELD(VTYPE, VILL, sizeof(target_ulong) * 8 - 1, 1)
113 
114 struct CPURISCVState {
115     target_ulong gpr[32];
116     target_ulong gprh[32]; /* 64 top bits of the 128-bit registers */
117     uint64_t fpr[32]; /* assume both F and D extensions */
118 
119     /* vector coprocessor state. */
120     uint64_t vreg[32 * RV_VLEN_MAX / 64] QEMU_ALIGNED(16);
121     target_ulong vxrm;
122     target_ulong vxsat;
123     target_ulong vl;
124     target_ulong vstart;
125     target_ulong vtype;
126 
127     target_ulong pc;
128     target_ulong load_res;
129     target_ulong load_val;
130 
131     target_ulong frm;
132 
133     target_ulong badaddr;
134     target_ulong guest_phys_fault_addr;
135 
136     target_ulong priv_ver;
137     target_ulong bext_ver;
138     target_ulong vext_ver;
139 
140     /* RISCVMXL, but uint32_t for vmstate migration */
141     uint32_t misa_mxl;      /* current mxl */
142     uint32_t misa_mxl_max;  /* max mxl for this cpu */
143     uint32_t misa_ext;      /* current extensions */
144     uint32_t misa_ext_mask; /* max ext for this cpu */
145 
146     /* 128-bit helpers upper part return value */
147     target_ulong retxh;
148 
149     uint32_t features;
150 
151 #ifdef CONFIG_USER_ONLY
152     uint32_t elf_flags;
153 #endif
154 
155 #ifndef CONFIG_USER_ONLY
156     target_ulong priv;
157     /* This contains QEMU specific information about the virt state. */
158     target_ulong virt;
159     target_ulong resetvec;
160 
161     target_ulong mhartid;
162     /*
163      * For RV32 this is 32-bit mstatus and 32-bit mstatush.
164      * For RV64 this is a 64-bit mstatus.
165      */
166     uint64_t mstatus;
167 
168     target_ulong mip;
169 
170     uint32_t miclaim;
171 
172     target_ulong mie;
173     target_ulong mideleg;
174 
175     target_ulong satp;   /* since: priv-1.10.0 */
176     target_ulong stval;
177     target_ulong medeleg;
178 
179     target_ulong stvec;
180     target_ulong sepc;
181     target_ulong scause;
182 
183     target_ulong mtvec;
184     target_ulong mepc;
185     target_ulong mcause;
186     target_ulong mtval;  /* since: priv-1.10.0 */
187 
188     /* Hypervisor CSRs */
189     target_ulong hstatus;
190     target_ulong hedeleg;
191     target_ulong hideleg;
192     target_ulong hcounteren;
193     target_ulong htval;
194     target_ulong htinst;
195     target_ulong hgatp;
196     uint64_t htimedelta;
197 
198     /* Virtual CSRs */
199     /*
200      * For RV32 this is 32-bit vsstatus and 32-bit vsstatush.
201      * For RV64 this is a 64-bit vsstatus.
202      */
203     uint64_t vsstatus;
204     target_ulong vstvec;
205     target_ulong vsscratch;
206     target_ulong vsepc;
207     target_ulong vscause;
208     target_ulong vstval;
209     target_ulong vsatp;
210 
211     target_ulong mtval2;
212     target_ulong mtinst;
213 
214     /* HS Backup CSRs */
215     target_ulong stvec_hs;
216     target_ulong sscratch_hs;
217     target_ulong sepc_hs;
218     target_ulong scause_hs;
219     target_ulong stval_hs;
220     target_ulong satp_hs;
221     uint64_t mstatus_hs;
222 
223     /* Signals whether the current exception occurred with two-stage address
224        translation active. */
225     bool two_stage_lookup;
226 
227     target_ulong scounteren;
228     target_ulong mcounteren;
229 
230     target_ulong sscratch;
231     target_ulong mscratch;
232 
233     /* temporary htif regs */
234     uint64_t mfromhost;
235     uint64_t mtohost;
236     uint64_t timecmp;
237 
238     /* physical memory protection */
239     pmp_table_t pmp_state;
240     target_ulong mseccfg;
241 
242     /* machine specific rdtime callback */
243     uint64_t (*rdtime_fn)(uint32_t);
244     uint32_t rdtime_fn_arg;
245 
246     /* True if in debugger mode.  */
247     bool debugger;
248 
249     /*
250      * CSRs for PointerMasking extension
251      */
252     target_ulong mmte;
253     target_ulong mpmmask;
254     target_ulong mpmbase;
255     target_ulong spmmask;
256     target_ulong spmbase;
257     target_ulong upmmask;
258     target_ulong upmbase;
259 #endif
260 
261     float_status fp_status;
262 
263     /* Fields from here on are preserved across CPU reset. */
264     QEMUTimer *timer; /* Internal timer */
265 };
266 
267 OBJECT_DECLARE_TYPE(RISCVCPU, RISCVCPUClass,
268                     RISCV_CPU)
269 
270 /**
271  * RISCVCPUClass:
272  * @parent_realize: The parent class' realize handler.
273  * @parent_reset: The parent class' reset handler.
274  *
275  * A RISCV CPU model.
276  */
277 struct RISCVCPUClass {
278     /*< private >*/
279     CPUClass parent_class;
280     /*< public >*/
281     DeviceRealize parent_realize;
282     DeviceReset parent_reset;
283 };
284 
285 /**
286  * RISCVCPU:
287  * @env: #CPURISCVState
288  *
289  * A RISCV CPU.
290  */
291 struct RISCVCPU {
292     /*< private >*/
293     CPUState parent_obj;
294     /*< public >*/
295     CPUNegativeOffsetState neg;
296     CPURISCVState env;
297 
298     char *dyn_csr_xml;
299     char *dyn_vreg_xml;
300 
301     /* Configuration Settings */
302     struct {
303         bool ext_i;
304         bool ext_e;
305         bool ext_g;
306         bool ext_m;
307         bool ext_a;
308         bool ext_f;
309         bool ext_d;
310         bool ext_c;
311         bool ext_s;
312         bool ext_u;
313         bool ext_h;
314         bool ext_j;
315         bool ext_v;
316         bool ext_zba;
317         bool ext_zbb;
318         bool ext_zbc;
319         bool ext_zbs;
320         bool ext_counters;
321         bool ext_ifencei;
322         bool ext_icsr;
323         bool ext_zfh;
324         bool ext_zfhmin;
325 
326         char *priv_spec;
327         char *user_spec;
328         char *bext_spec;
329         char *vext_spec;
330         uint16_t vlen;
331         uint16_t elen;
332         bool mmu;
333         bool pmp;
334         bool epmp;
335         uint64_t resetvec;
336     } cfg;
337 };
338 
339 static inline int riscv_has_ext(CPURISCVState *env, target_ulong ext)
340 {
341     return (env->misa_ext & ext) != 0;
342 }
343 
344 static inline bool riscv_feature(CPURISCVState *env, int feature)
345 {
346     return env->features & (1ULL << feature);
347 }
348 
349 #include "cpu_user.h"
350 
351 extern const char * const riscv_int_regnames[];
352 extern const char * const riscv_int_regnamesh[];
353 extern const char * const riscv_fpr_regnames[];
354 
355 const char *riscv_cpu_get_trap_name(target_ulong cause, bool async);
356 void riscv_cpu_do_interrupt(CPUState *cpu);
357 int riscv_cpu_write_elf64_note(WriteCoreDumpFunction f, CPUState *cs,
358                                int cpuid, void *opaque);
359 int riscv_cpu_write_elf32_note(WriteCoreDumpFunction f, CPUState *cs,
360                                int cpuid, void *opaque);
361 int riscv_cpu_gdb_read_register(CPUState *cpu, GByteArray *buf, int reg);
362 int riscv_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);
363 bool riscv_cpu_fp_enabled(CPURISCVState *env);
364 bool riscv_cpu_vector_enabled(CPURISCVState *env);
365 bool riscv_cpu_virt_enabled(CPURISCVState *env);
366 void riscv_cpu_set_virt_enabled(CPURISCVState *env, bool enable);
367 bool riscv_cpu_two_stage_lookup(int mmu_idx);
368 int riscv_cpu_mmu_index(CPURISCVState *env, bool ifetch);
369 hwaddr riscv_cpu_get_phys_page_debug(CPUState *cpu, vaddr addr);
370 void  riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
371                                     MMUAccessType access_type, int mmu_idx,
372                                     uintptr_t retaddr) QEMU_NORETURN;
373 bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
374                         MMUAccessType access_type, int mmu_idx,
375                         bool probe, uintptr_t retaddr);
376 void riscv_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr,
377                                      vaddr addr, unsigned size,
378                                      MMUAccessType access_type,
379                                      int mmu_idx, MemTxAttrs attrs,
380                                      MemTxResult response, uintptr_t retaddr);
381 char *riscv_isa_string(RISCVCPU *cpu);
382 void riscv_cpu_list(void);
383 
384 #define cpu_list riscv_cpu_list
385 #define cpu_mmu_index riscv_cpu_mmu_index
386 
387 #ifndef CONFIG_USER_ONLY
388 bool riscv_cpu_exec_interrupt(CPUState *cs, int interrupt_request);
389 void riscv_cpu_swap_hypervisor_regs(CPURISCVState *env);
390 int riscv_cpu_claim_interrupts(RISCVCPU *cpu, uint32_t interrupts);
391 uint32_t riscv_cpu_update_mip(RISCVCPU *cpu, uint32_t mask, uint32_t value);
392 #define BOOL_TO_MASK(x) (-!!(x)) /* helper for riscv_cpu_update_mip value */
393 void riscv_cpu_set_rdtime_fn(CPURISCVState *env, uint64_t (*fn)(uint32_t),
394                              uint32_t arg);
395 #endif
396 void riscv_cpu_set_mode(CPURISCVState *env, target_ulong newpriv);
397 
398 void riscv_translate_init(void);
399 void QEMU_NORETURN riscv_raise_exception(CPURISCVState *env,
400                                          uint32_t exception, uintptr_t pc);
401 
402 target_ulong riscv_cpu_get_fflags(CPURISCVState *env);
403 void riscv_cpu_set_fflags(CPURISCVState *env, target_ulong);
404 
405 #define TB_FLAGS_PRIV_MMU_MASK                3
406 #define TB_FLAGS_PRIV_HYP_ACCESS_MASK   (1 << 2)
407 #define TB_FLAGS_MSTATUS_FS MSTATUS_FS
408 #define TB_FLAGS_MSTATUS_VS MSTATUS_VS
409 
410 typedef CPURISCVState CPUArchState;
411 typedef RISCVCPU ArchCPU;
412 #include "exec/cpu-all.h"
413 
414 FIELD(TB_FLAGS, MEM_IDX, 0, 3)
415 FIELD(TB_FLAGS, LMUL, 3, 3)
416 FIELD(TB_FLAGS, SEW, 6, 3)
417 /* Skip MSTATUS_VS (0x600) bits */
418 FIELD(TB_FLAGS, VL_EQ_VLMAX, 11, 1)
419 FIELD(TB_FLAGS, VILL, 12, 1)
420 /* Skip MSTATUS_FS (0x6000) bits */
421 /* Is a Hypervisor instruction load/store allowed? */
422 FIELD(TB_FLAGS, HLSX, 15, 1)
423 FIELD(TB_FLAGS, MSTATUS_HS_FS, 16, 2)
424 FIELD(TB_FLAGS, MSTATUS_HS_VS, 18, 2)
425 /* The combination of MXL/SXL/UXL that applies to the current cpu mode. */
426 FIELD(TB_FLAGS, XL, 20, 2)
427 /* If PointerMasking should be applied */
428 FIELD(TB_FLAGS, PM_ENABLED, 22, 1)
429 
430 #ifdef TARGET_RISCV32
431 #define riscv_cpu_mxl(env)  ((void)(env), MXL_RV32)
432 #else
433 static inline RISCVMXL riscv_cpu_mxl(CPURISCVState *env)
434 {
435     return env->misa_mxl;
436 }
437 #endif
438 
439 /*
440  * Encode LMUL to lmul as follows:
441  *     LMUL    vlmul    lmul
442  *      1       000       0
443  *      2       001       1
444  *      4       010       2
445  *      8       011       3
446  *      -       100       -
447  *     1/8      101      -3
448  *     1/4      110      -2
449  *     1/2      111      -1
450  *
451  * then, we can calculate VLMAX = vlen >> (vsew + 3 - lmul)
452  * e.g. vlen = 256 bits, SEW = 16, LMUL = 1/8
453  *      => VLMAX = vlen >> (1 + 3 - (-3))
454  *               = 256 >> 7
455  *               = 2
456  */
457 static inline uint32_t vext_get_vlmax(RISCVCPU *cpu, target_ulong vtype)
458 {
459     uint8_t sew = FIELD_EX64(vtype, VTYPE, VSEW);
460     int8_t lmul = sextract32(FIELD_EX64(vtype, VTYPE, VLMUL), 0, 3);
461     return cpu->cfg.vlen >> (sew + 3 - lmul);
462 }
463 
464 void cpu_get_tb_cpu_state(CPURISCVState *env, target_ulong *pc,
465                           target_ulong *cs_base, uint32_t *pflags);
466 
467 RISCVException riscv_csrrw(CPURISCVState *env, int csrno,
468                            target_ulong *ret_value,
469                            target_ulong new_value, target_ulong write_mask);
470 RISCVException riscv_csrrw_debug(CPURISCVState *env, int csrno,
471                                  target_ulong *ret_value,
472                                  target_ulong new_value,
473                                  target_ulong write_mask);
474 
475 static inline void riscv_csr_write(CPURISCVState *env, int csrno,
476                                    target_ulong val)
477 {
478     riscv_csrrw(env, csrno, NULL, val, MAKE_64BIT_MASK(0, TARGET_LONG_BITS));
479 }
480 
481 static inline target_ulong riscv_csr_read(CPURISCVState *env, int csrno)
482 {
483     target_ulong val = 0;
484     riscv_csrrw(env, csrno, &val, 0, 0);
485     return val;
486 }
487 
488 typedef RISCVException (*riscv_csr_predicate_fn)(CPURISCVState *env,
489                                                  int csrno);
490 typedef RISCVException (*riscv_csr_read_fn)(CPURISCVState *env, int csrno,
491                                             target_ulong *ret_value);
492 typedef RISCVException (*riscv_csr_write_fn)(CPURISCVState *env, int csrno,
493                                              target_ulong new_value);
494 typedef RISCVException (*riscv_csr_op_fn)(CPURISCVState *env, int csrno,
495                                           target_ulong *ret_value,
496                                           target_ulong new_value,
497                                           target_ulong write_mask);
498 
499 typedef struct {
500     const char *name;
501     riscv_csr_predicate_fn predicate;
502     riscv_csr_read_fn read;
503     riscv_csr_write_fn write;
504     riscv_csr_op_fn op;
505 } riscv_csr_operations;
506 
507 /* CSR function table constants */
508 enum {
509     CSR_TABLE_SIZE = 0x1000
510 };
511 
512 /* CSR function table */
513 extern riscv_csr_operations csr_ops[CSR_TABLE_SIZE];
514 
515 void riscv_get_csr_ops(int csrno, riscv_csr_operations *ops);
516 void riscv_set_csr_ops(int csrno, riscv_csr_operations *ops);
517 
518 void riscv_cpu_register_gdb_regs_for_features(CPUState *cs);
519 
520 #endif /* RISCV_CPU_H */
521