xref: /openbmc/qemu/target/riscv/cpu.h (revision 6ddc7069)
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 
29 #define TCG_GUEST_DEFAULT_MO 0
30 
31 #define TYPE_RISCV_CPU "riscv-cpu"
32 
33 #define RISCV_CPU_TYPE_SUFFIX "-" TYPE_RISCV_CPU
34 #define RISCV_CPU_TYPE_NAME(name) (name RISCV_CPU_TYPE_SUFFIX)
35 #define CPU_RESOLVING_TYPE TYPE_RISCV_CPU
36 
37 #define TYPE_RISCV_CPU_ANY              RISCV_CPU_TYPE_NAME("any")
38 #define TYPE_RISCV_CPU_BASE32           RISCV_CPU_TYPE_NAME("rv32")
39 #define TYPE_RISCV_CPU_BASE64           RISCV_CPU_TYPE_NAME("rv64")
40 #define TYPE_RISCV_CPU_IBEX             RISCV_CPU_TYPE_NAME("lowrisc-ibex")
41 #define TYPE_RISCV_CPU_SHAKTI_C         RISCV_CPU_TYPE_NAME("shakti-c")
42 #define TYPE_RISCV_CPU_SIFIVE_E31       RISCV_CPU_TYPE_NAME("sifive-e31")
43 #define TYPE_RISCV_CPU_SIFIVE_E34       RISCV_CPU_TYPE_NAME("sifive-e34")
44 #define TYPE_RISCV_CPU_SIFIVE_E51       RISCV_CPU_TYPE_NAME("sifive-e51")
45 #define TYPE_RISCV_CPU_SIFIVE_U34       RISCV_CPU_TYPE_NAME("sifive-u34")
46 #define TYPE_RISCV_CPU_SIFIVE_U54       RISCV_CPU_TYPE_NAME("sifive-u54")
47 
48 #if defined(TARGET_RISCV32)
49 # define TYPE_RISCV_CPU_BASE            TYPE_RISCV_CPU_BASE32
50 #elif defined(TARGET_RISCV64)
51 # define TYPE_RISCV_CPU_BASE            TYPE_RISCV_CPU_BASE64
52 #endif
53 
54 #define RV32 ((target_ulong)1 << (TARGET_LONG_BITS - 2))
55 #define RV64 ((target_ulong)2 << (TARGET_LONG_BITS - 2))
56 
57 #if defined(TARGET_RISCV32)
58 #define RVXLEN RV32
59 #elif defined(TARGET_RISCV64)
60 #define RVXLEN RV64
61 #endif
62 
63 #define RV(x) ((target_ulong)1 << (x - 'A'))
64 
65 #define RVI RV('I')
66 #define RVE RV('E') /* E and I are mutually exclusive */
67 #define RVM RV('M')
68 #define RVA RV('A')
69 #define RVF RV('F')
70 #define RVD RV('D')
71 #define RVV RV('V')
72 #define RVC RV('C')
73 #define RVS RV('S')
74 #define RVU RV('U')
75 #define RVH RV('H')
76 
77 /* S extension denotes that Supervisor mode exists, however it is possible
78    to have a core that support S mode but does not have an MMU and there
79    is currently no bit in misa to indicate whether an MMU exists or not
80    so a cpu features bitfield is required, likewise for optional PMP support */
81 enum {
82     RISCV_FEATURE_MMU,
83     RISCV_FEATURE_PMP,
84     RISCV_FEATURE_MISA
85 };
86 
87 #define PRIV_VERSION_1_10_0 0x00011000
88 #define PRIV_VERSION_1_11_0 0x00011100
89 
90 #define VEXT_VERSION_0_07_1 0x00000701
91 
92 enum {
93     TRANSLATE_SUCCESS,
94     TRANSLATE_FAIL,
95     TRANSLATE_PMP_FAIL,
96     TRANSLATE_G_STAGE_FAIL
97 };
98 
99 #define MMU_USER_IDX 3
100 
101 #define MAX_RISCV_PMPS (16)
102 
103 typedef struct CPURISCVState CPURISCVState;
104 
105 #include "pmp.h"
106 
107 #define RV_VLEN_MAX 256
108 
109 FIELD(VTYPE, VLMUL, 0, 2)
110 FIELD(VTYPE, VSEW, 2, 3)
111 FIELD(VTYPE, VEDIV, 5, 2)
112 FIELD(VTYPE, RESERVED, 7, sizeof(target_ulong) * 8 - 9)
113 FIELD(VTYPE, VILL, sizeof(target_ulong) * 8 - 1, 1)
114 
115 struct CPURISCVState {
116     target_ulong gpr[32];
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 vext_ver;
138     target_ulong misa;
139     target_ulong misa_mask;
140 
141     uint32_t features;
142 
143 #ifdef CONFIG_USER_ONLY
144     uint32_t elf_flags;
145 #endif
146 
147 #ifndef CONFIG_USER_ONLY
148     target_ulong priv;
149     /* This contains QEMU specific information about the virt state. */
150     target_ulong virt;
151     target_ulong resetvec;
152 
153     target_ulong mhartid;
154     /*
155      * For RV32 this is 32-bit mstatus and 32-bit mstatush.
156      * For RV64 this is a 64-bit mstatus.
157      */
158     uint64_t mstatus;
159 
160     target_ulong mip;
161 
162     uint32_t miclaim;
163 
164     target_ulong mie;
165     target_ulong mideleg;
166 
167     target_ulong satp;   /* since: priv-1.10.0 */
168     target_ulong stval;
169     target_ulong medeleg;
170 
171     target_ulong stvec;
172     target_ulong sepc;
173     target_ulong scause;
174 
175     target_ulong mtvec;
176     target_ulong mepc;
177     target_ulong mcause;
178     target_ulong mtval;  /* since: priv-1.10.0 */
179 
180     /* Hypervisor CSRs */
181     target_ulong hstatus;
182     target_ulong hedeleg;
183     target_ulong hideleg;
184     target_ulong hcounteren;
185     target_ulong htval;
186     target_ulong htinst;
187     target_ulong hgatp;
188     uint64_t htimedelta;
189 
190     /* Virtual CSRs */
191     /*
192      * For RV32 this is 32-bit vsstatus and 32-bit vsstatush.
193      * For RV64 this is a 64-bit vsstatus.
194      */
195     uint64_t vsstatus;
196     target_ulong vstvec;
197     target_ulong vsscratch;
198     target_ulong vsepc;
199     target_ulong vscause;
200     target_ulong vstval;
201     target_ulong vsatp;
202 
203     target_ulong mtval2;
204     target_ulong mtinst;
205 
206     /* HS Backup CSRs */
207     target_ulong stvec_hs;
208     target_ulong sscratch_hs;
209     target_ulong sepc_hs;
210     target_ulong scause_hs;
211     target_ulong stval_hs;
212     target_ulong satp_hs;
213     uint64_t mstatus_hs;
214 
215     /* Signals whether the current exception occurred with two-stage address
216        translation active. */
217     bool two_stage_lookup;
218 
219     target_ulong scounteren;
220     target_ulong mcounteren;
221 
222     target_ulong sscratch;
223     target_ulong mscratch;
224 
225     /* temporary htif regs */
226     uint64_t mfromhost;
227     uint64_t mtohost;
228     uint64_t timecmp;
229 
230     /* physical memory protection */
231     pmp_table_t pmp_state;
232 
233     /* machine specific rdtime callback */
234     uint64_t (*rdtime_fn)(uint32_t);
235     uint32_t rdtime_fn_arg;
236 
237     /* True if in debugger mode.  */
238     bool debugger;
239 #endif
240 
241     float_status fp_status;
242 
243     /* Fields from here on are preserved across CPU reset. */
244     QEMUTimer *timer; /* Internal timer */
245 };
246 
247 OBJECT_DECLARE_TYPE(RISCVCPU, RISCVCPUClass,
248                     RISCV_CPU)
249 
250 /**
251  * RISCVCPUClass:
252  * @parent_realize: The parent class' realize handler.
253  * @parent_reset: The parent class' reset handler.
254  *
255  * A RISCV CPU model.
256  */
257 struct RISCVCPUClass {
258     /*< private >*/
259     CPUClass parent_class;
260     /*< public >*/
261     DeviceRealize parent_realize;
262     DeviceReset parent_reset;
263 };
264 
265 /**
266  * RISCVCPU:
267  * @env: #CPURISCVState
268  *
269  * A RISCV CPU.
270  */
271 struct RISCVCPU {
272     /*< private >*/
273     CPUState parent_obj;
274     /*< public >*/
275     CPUNegativeOffsetState neg;
276     CPURISCVState env;
277 
278     char *dyn_csr_xml;
279 
280     /* Configuration Settings */
281     struct {
282         bool ext_i;
283         bool ext_e;
284         bool ext_g;
285         bool ext_m;
286         bool ext_a;
287         bool ext_f;
288         bool ext_d;
289         bool ext_c;
290         bool ext_s;
291         bool ext_u;
292         bool ext_h;
293         bool ext_v;
294         bool ext_counters;
295         bool ext_ifencei;
296         bool ext_icsr;
297 
298         char *priv_spec;
299         char *user_spec;
300         char *vext_spec;
301         uint16_t vlen;
302         uint16_t elen;
303         bool mmu;
304         bool pmp;
305         uint64_t resetvec;
306     } cfg;
307 };
308 
309 static inline int riscv_has_ext(CPURISCVState *env, target_ulong ext)
310 {
311     return (env->misa & ext) != 0;
312 }
313 
314 static inline bool riscv_feature(CPURISCVState *env, int feature)
315 {
316     return env->features & (1ULL << feature);
317 }
318 
319 #include "cpu_user.h"
320 #include "cpu_bits.h"
321 
322 extern const char * const riscv_int_regnames[];
323 extern const char * const riscv_fpr_regnames[];
324 extern const char * const riscv_excp_names[];
325 extern const char * const riscv_intr_names[];
326 
327 const char *riscv_cpu_get_trap_name(target_ulong cause, bool async);
328 void riscv_cpu_do_interrupt(CPUState *cpu);
329 int riscv_cpu_write_elf64_note(WriteCoreDumpFunction f, CPUState *cs,
330                                int cpuid, void *opaque);
331 int riscv_cpu_write_elf32_note(WriteCoreDumpFunction f, CPUState *cs,
332                                int cpuid, void *opaque);
333 int riscv_cpu_gdb_read_register(CPUState *cpu, GByteArray *buf, int reg);
334 int riscv_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);
335 bool riscv_cpu_exec_interrupt(CPUState *cs, int interrupt_request);
336 bool riscv_cpu_fp_enabled(CPURISCVState *env);
337 bool riscv_cpu_virt_enabled(CPURISCVState *env);
338 void riscv_cpu_set_virt_enabled(CPURISCVState *env, bool enable);
339 bool riscv_cpu_force_hs_excep_enabled(CPURISCVState *env);
340 void riscv_cpu_set_force_hs_excep(CPURISCVState *env, bool enable);
341 bool riscv_cpu_two_stage_lookup(int mmu_idx);
342 int riscv_cpu_mmu_index(CPURISCVState *env, bool ifetch);
343 hwaddr riscv_cpu_get_phys_page_debug(CPUState *cpu, vaddr addr);
344 void  riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
345                                     MMUAccessType access_type, int mmu_idx,
346                                     uintptr_t retaddr);
347 bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
348                         MMUAccessType access_type, int mmu_idx,
349                         bool probe, uintptr_t retaddr);
350 void riscv_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr,
351                                      vaddr addr, unsigned size,
352                                      MMUAccessType access_type,
353                                      int mmu_idx, MemTxAttrs attrs,
354                                      MemTxResult response, uintptr_t retaddr);
355 char *riscv_isa_string(RISCVCPU *cpu);
356 void riscv_cpu_list(void);
357 
358 #define cpu_signal_handler riscv_cpu_signal_handler
359 #define cpu_list riscv_cpu_list
360 #define cpu_mmu_index riscv_cpu_mmu_index
361 
362 #ifndef CONFIG_USER_ONLY
363 void riscv_cpu_swap_hypervisor_regs(CPURISCVState *env);
364 int riscv_cpu_claim_interrupts(RISCVCPU *cpu, uint32_t interrupts);
365 uint32_t riscv_cpu_update_mip(RISCVCPU *cpu, uint32_t mask, uint32_t value);
366 #define BOOL_TO_MASK(x) (-!!(x)) /* helper for riscv_cpu_update_mip value */
367 void riscv_cpu_set_rdtime_fn(CPURISCVState *env, uint64_t (*fn)(uint32_t),
368                              uint32_t arg);
369 #endif
370 void riscv_cpu_set_mode(CPURISCVState *env, target_ulong newpriv);
371 
372 void riscv_translate_init(void);
373 int riscv_cpu_signal_handler(int host_signum, void *pinfo, void *puc);
374 void QEMU_NORETURN riscv_raise_exception(CPURISCVState *env,
375                                          uint32_t exception, uintptr_t pc);
376 
377 target_ulong riscv_cpu_get_fflags(CPURISCVState *env);
378 void riscv_cpu_set_fflags(CPURISCVState *env, target_ulong);
379 
380 #define TB_FLAGS_MMU_MASK   7
381 #define TB_FLAGS_PRIV_MMU_MASK                3
382 #define TB_FLAGS_PRIV_HYP_ACCESS_MASK   (1 << 2)
383 #define TB_FLAGS_MSTATUS_FS MSTATUS_FS
384 
385 typedef CPURISCVState CPUArchState;
386 typedef RISCVCPU ArchCPU;
387 #include "exec/cpu-all.h"
388 
389 FIELD(TB_FLAGS, VL_EQ_VLMAX, 2, 1)
390 FIELD(TB_FLAGS, LMUL, 3, 2)
391 FIELD(TB_FLAGS, SEW, 5, 3)
392 FIELD(TB_FLAGS, VILL, 8, 1)
393 /* Is a Hypervisor instruction load/store allowed? */
394 FIELD(TB_FLAGS, HLSX, 9, 1)
395 
396 bool riscv_cpu_is_32bit(CPURISCVState *env);
397 
398 /*
399  * A simplification for VLMAX
400  * = (1 << LMUL) * VLEN / (8 * (1 << SEW))
401  * = (VLEN << LMUL) / (8 << SEW)
402  * = (VLEN << LMUL) >> (SEW + 3)
403  * = VLEN >> (SEW + 3 - LMUL)
404  */
405 static inline uint32_t vext_get_vlmax(RISCVCPU *cpu, target_ulong vtype)
406 {
407     uint8_t sew, lmul;
408 
409     sew = FIELD_EX64(vtype, VTYPE, VSEW);
410     lmul = FIELD_EX64(vtype, VTYPE, VLMUL);
411     return cpu->cfg.vlen >> (sew + 3 - lmul);
412 }
413 
414 static inline void cpu_get_tb_cpu_state(CPURISCVState *env, target_ulong *pc,
415                                         target_ulong *cs_base, uint32_t *pflags)
416 {
417     uint32_t flags = 0;
418 
419     *pc = env->pc;
420     *cs_base = 0;
421 
422     if (riscv_has_ext(env, RVV)) {
423         uint32_t vlmax = vext_get_vlmax(env_archcpu(env), env->vtype);
424         bool vl_eq_vlmax = (env->vstart == 0) && (vlmax == env->vl);
425         flags = FIELD_DP32(flags, TB_FLAGS, VILL,
426                     FIELD_EX64(env->vtype, VTYPE, VILL));
427         flags = FIELD_DP32(flags, TB_FLAGS, SEW,
428                     FIELD_EX64(env->vtype, VTYPE, VSEW));
429         flags = FIELD_DP32(flags, TB_FLAGS, LMUL,
430                     FIELD_EX64(env->vtype, VTYPE, VLMUL));
431         flags = FIELD_DP32(flags, TB_FLAGS, VL_EQ_VLMAX, vl_eq_vlmax);
432     } else {
433         flags = FIELD_DP32(flags, TB_FLAGS, VILL, 1);
434     }
435 
436 #ifdef CONFIG_USER_ONLY
437     flags |= TB_FLAGS_MSTATUS_FS;
438 #else
439     flags |= cpu_mmu_index(env, 0);
440     if (riscv_cpu_fp_enabled(env)) {
441         flags |= env->mstatus & MSTATUS_FS;
442     }
443 
444     if (riscv_has_ext(env, RVH)) {
445         if (env->priv == PRV_M ||
446             (env->priv == PRV_S && !riscv_cpu_virt_enabled(env)) ||
447             (env->priv == PRV_U && !riscv_cpu_virt_enabled(env) &&
448                 get_field(env->hstatus, HSTATUS_HU))) {
449             flags = FIELD_DP32(flags, TB_FLAGS, HLSX, 1);
450         }
451     }
452 #endif
453 
454     *pflags = flags;
455 }
456 
457 int riscv_csrrw(CPURISCVState *env, int csrno, target_ulong *ret_value,
458                 target_ulong new_value, target_ulong write_mask);
459 int riscv_csrrw_debug(CPURISCVState *env, int csrno, target_ulong *ret_value,
460                       target_ulong new_value, target_ulong write_mask);
461 
462 static inline void riscv_csr_write(CPURISCVState *env, int csrno,
463                                    target_ulong val)
464 {
465     riscv_csrrw(env, csrno, NULL, val, MAKE_64BIT_MASK(0, TARGET_LONG_BITS));
466 }
467 
468 static inline target_ulong riscv_csr_read(CPURISCVState *env, int csrno)
469 {
470     target_ulong val = 0;
471     riscv_csrrw(env, csrno, &val, 0, 0);
472     return val;
473 }
474 
475 typedef int (*riscv_csr_predicate_fn)(CPURISCVState *env, int csrno);
476 typedef int (*riscv_csr_read_fn)(CPURISCVState *env, int csrno,
477     target_ulong *ret_value);
478 typedef int (*riscv_csr_write_fn)(CPURISCVState *env, int csrno,
479     target_ulong new_value);
480 typedef int (*riscv_csr_op_fn)(CPURISCVState *env, int csrno,
481     target_ulong *ret_value, target_ulong new_value, target_ulong write_mask);
482 
483 typedef struct {
484     const char *name;
485     riscv_csr_predicate_fn predicate;
486     riscv_csr_read_fn read;
487     riscv_csr_write_fn write;
488     riscv_csr_op_fn op;
489 } riscv_csr_operations;
490 
491 /* CSR function table constants */
492 enum {
493     CSR_TABLE_SIZE = 0x1000
494 };
495 
496 /* CSR function table */
497 extern riscv_csr_operations csr_ops[CSR_TABLE_SIZE];
498 
499 void riscv_get_csr_ops(int csrno, riscv_csr_operations *ops);
500 void riscv_set_csr_ops(int csrno, riscv_csr_operations *ops);
501 
502 void riscv_cpu_register_gdb_regs_for_features(CPUState *cs);
503 
504 #endif /* RISCV_CPU_H */
505