xref: /openbmc/qemu/target/riscv/cpu.h (revision ac12b601)
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_SIFIVE_E31       RISCV_CPU_TYPE_NAME("sifive-e31")
42 #define TYPE_RISCV_CPU_SIFIVE_E34       RISCV_CPU_TYPE_NAME("sifive-e34")
43 #define TYPE_RISCV_CPU_SIFIVE_E51       RISCV_CPU_TYPE_NAME("sifive-e51")
44 #define TYPE_RISCV_CPU_SIFIVE_U34       RISCV_CPU_TYPE_NAME("sifive-u34")
45 #define TYPE_RISCV_CPU_SIFIVE_U54       RISCV_CPU_TYPE_NAME("sifive-u54")
46 
47 #if defined(TARGET_RISCV32)
48 # define TYPE_RISCV_CPU_BASE            TYPE_RISCV_CPU_BASE32
49 #elif defined(TARGET_RISCV64)
50 # define TYPE_RISCV_CPU_BASE            TYPE_RISCV_CPU_BASE64
51 #endif
52 
53 #define RV32 ((target_ulong)1 << (TARGET_LONG_BITS - 2))
54 #define RV64 ((target_ulong)2 << (TARGET_LONG_BITS - 2))
55 
56 #if defined(TARGET_RISCV32)
57 #define RVXLEN RV32
58 #elif defined(TARGET_RISCV64)
59 #define RVXLEN RV64
60 #endif
61 
62 #define RV(x) ((target_ulong)1 << (x - 'A'))
63 
64 #define RVI RV('I')
65 #define RVE RV('E') /* E and I are mutually exclusive */
66 #define RVM RV('M')
67 #define RVA RV('A')
68 #define RVF RV('F')
69 #define RVD RV('D')
70 #define RVV RV('V')
71 #define RVC RV('C')
72 #define RVS RV('S')
73 #define RVU RV('U')
74 #define RVH RV('H')
75 
76 /* S extension denotes that Supervisor mode exists, however it is possible
77    to have a core that support S mode but does not have an MMU and there
78    is currently no bit in misa to indicate whether an MMU exists or not
79    so a cpu features bitfield is required, likewise for optional PMP support */
80 enum {
81     RISCV_FEATURE_MMU,
82     RISCV_FEATURE_PMP,
83     RISCV_FEATURE_MISA
84 };
85 
86 #define PRIV_VERSION_1_10_0 0x00011000
87 #define PRIV_VERSION_1_11_0 0x00011100
88 
89 #define VEXT_VERSION_0_07_1 0x00000701
90 
91 enum {
92     TRANSLATE_SUCCESS,
93     TRANSLATE_FAIL,
94     TRANSLATE_PMP_FAIL,
95     TRANSLATE_G_STAGE_FAIL
96 };
97 
98 #define MMU_USER_IDX 3
99 
100 #define MAX_RISCV_PMPS (16)
101 
102 typedef struct CPURISCVState CPURISCVState;
103 
104 #include "pmp.h"
105 
106 #define RV_VLEN_MAX 256
107 
108 FIELD(VTYPE, VLMUL, 0, 2)
109 FIELD(VTYPE, VSEW, 2, 3)
110 FIELD(VTYPE, VEDIV, 5, 2)
111 FIELD(VTYPE, RESERVED, 7, sizeof(target_ulong) * 8 - 9)
112 FIELD(VTYPE, VILL, sizeof(target_ulong) * 8 - 1, 1)
113 
114 struct CPURISCVState {
115     target_ulong gpr[32];
116     uint64_t fpr[32]; /* assume both F and D extensions */
117 
118     /* vector coprocessor state. */
119     uint64_t vreg[32 * RV_VLEN_MAX / 64] QEMU_ALIGNED(16);
120     target_ulong vxrm;
121     target_ulong vxsat;
122     target_ulong vl;
123     target_ulong vstart;
124     target_ulong vtype;
125 
126     target_ulong pc;
127     target_ulong load_res;
128     target_ulong load_val;
129 
130     target_ulong frm;
131 
132     target_ulong badaddr;
133     target_ulong guest_phys_fault_addr;
134 
135     target_ulong priv_ver;
136     target_ulong vext_ver;
137     target_ulong misa;
138     target_ulong misa_mask;
139 
140     uint32_t features;
141 
142 #ifdef CONFIG_USER_ONLY
143     uint32_t elf_flags;
144 #endif
145 
146 #ifndef CONFIG_USER_ONLY
147     target_ulong priv;
148     /* This contains QEMU specific information about the virt state. */
149     target_ulong virt;
150     target_ulong resetvec;
151 
152     target_ulong mhartid;
153     /*
154      * For RV32 this is 32-bit mstatus and 32-bit mstatush.
155      * For RV64 this is a 64-bit mstatus.
156      */
157     uint64_t mstatus;
158 
159     target_ulong mip;
160 
161     uint32_t miclaim;
162 
163     target_ulong mie;
164     target_ulong mideleg;
165 
166     target_ulong satp;   /* since: priv-1.10.0 */
167     target_ulong stval;
168     target_ulong medeleg;
169 
170     target_ulong stvec;
171     target_ulong sepc;
172     target_ulong scause;
173 
174     target_ulong mtvec;
175     target_ulong mepc;
176     target_ulong mcause;
177     target_ulong mtval;  /* since: priv-1.10.0 */
178 
179     /* Hypervisor CSRs */
180     target_ulong hstatus;
181     target_ulong hedeleg;
182     target_ulong hideleg;
183     target_ulong hcounteren;
184     target_ulong htval;
185     target_ulong htinst;
186     target_ulong hgatp;
187     uint64_t htimedelta;
188 
189     /* Virtual CSRs */
190     /*
191      * For RV32 this is 32-bit vsstatus and 32-bit vsstatush.
192      * For RV64 this is a 64-bit vsstatus.
193      */
194     uint64_t vsstatus;
195     target_ulong vstvec;
196     target_ulong vsscratch;
197     target_ulong vsepc;
198     target_ulong vscause;
199     target_ulong vstval;
200     target_ulong vsatp;
201 
202     target_ulong mtval2;
203     target_ulong mtinst;
204 
205     /* HS Backup CSRs */
206     target_ulong stvec_hs;
207     target_ulong sscratch_hs;
208     target_ulong sepc_hs;
209     target_ulong scause_hs;
210     target_ulong stval_hs;
211     target_ulong satp_hs;
212     uint64_t mstatus_hs;
213 
214     /* Signals whether the current exception occurred with two-stage address
215        translation active. */
216     bool two_stage_lookup;
217 
218     target_ulong scounteren;
219     target_ulong mcounteren;
220 
221     target_ulong sscratch;
222     target_ulong mscratch;
223 
224     /* temporary htif regs */
225     uint64_t mfromhost;
226     uint64_t mtohost;
227     uint64_t timecmp;
228 
229     /* physical memory protection */
230     pmp_table_t pmp_state;
231 
232     /* machine specific rdtime callback */
233     uint64_t (*rdtime_fn)(uint32_t);
234     uint32_t rdtime_fn_arg;
235 
236     /* True if in debugger mode.  */
237     bool debugger;
238 #endif
239 
240     float_status fp_status;
241 
242     /* Fields from here on are preserved across CPU reset. */
243     QEMUTimer *timer; /* Internal timer */
244 };
245 
246 OBJECT_DECLARE_TYPE(RISCVCPU, RISCVCPUClass,
247                     RISCV_CPU)
248 
249 /**
250  * RISCVCPUClass:
251  * @parent_realize: The parent class' realize handler.
252  * @parent_reset: The parent class' reset handler.
253  *
254  * A RISCV CPU model.
255  */
256 struct RISCVCPUClass {
257     /*< private >*/
258     CPUClass parent_class;
259     /*< public >*/
260     DeviceRealize parent_realize;
261     DeviceReset parent_reset;
262 };
263 
264 /**
265  * RISCVCPU:
266  * @env: #CPURISCVState
267  *
268  * A RISCV CPU.
269  */
270 struct RISCVCPU {
271     /*< private >*/
272     CPUState parent_obj;
273     /*< public >*/
274     CPUNegativeOffsetState neg;
275     CPURISCVState env;
276 
277     char *dyn_csr_xml;
278 
279     /* Configuration Settings */
280     struct {
281         bool ext_i;
282         bool ext_e;
283         bool ext_g;
284         bool ext_m;
285         bool ext_a;
286         bool ext_f;
287         bool ext_d;
288         bool ext_c;
289         bool ext_s;
290         bool ext_u;
291         bool ext_h;
292         bool ext_v;
293         bool ext_counters;
294         bool ext_ifencei;
295         bool ext_icsr;
296 
297         char *priv_spec;
298         char *user_spec;
299         char *vext_spec;
300         uint16_t vlen;
301         uint16_t elen;
302         bool mmu;
303         bool pmp;
304         uint64_t resetvec;
305     } cfg;
306 };
307 
308 static inline int riscv_has_ext(CPURISCVState *env, target_ulong ext)
309 {
310     return (env->misa & ext) != 0;
311 }
312 
313 static inline bool riscv_feature(CPURISCVState *env, int feature)
314 {
315     return env->features & (1ULL << feature);
316 }
317 
318 #include "cpu_user.h"
319 #include "cpu_bits.h"
320 
321 extern const char * const riscv_int_regnames[];
322 extern const char * const riscv_fpr_regnames[];
323 extern const char * const riscv_excp_names[];
324 extern const char * const riscv_intr_names[];
325 
326 const char *riscv_cpu_get_trap_name(target_ulong cause, bool async);
327 void riscv_cpu_do_interrupt(CPUState *cpu);
328 int riscv_cpu_write_elf64_note(WriteCoreDumpFunction f, CPUState *cs,
329                                int cpuid, void *opaque);
330 int riscv_cpu_write_elf32_note(WriteCoreDumpFunction f, CPUState *cs,
331                                int cpuid, void *opaque);
332 int riscv_cpu_gdb_read_register(CPUState *cpu, GByteArray *buf, int reg);
333 int riscv_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);
334 bool riscv_cpu_exec_interrupt(CPUState *cs, int interrupt_request);
335 bool riscv_cpu_fp_enabled(CPURISCVState *env);
336 bool riscv_cpu_virt_enabled(CPURISCVState *env);
337 void riscv_cpu_set_virt_enabled(CPURISCVState *env, bool enable);
338 bool riscv_cpu_force_hs_excep_enabled(CPURISCVState *env);
339 void riscv_cpu_set_force_hs_excep(CPURISCVState *env, bool enable);
340 bool riscv_cpu_two_stage_lookup(int mmu_idx);
341 int riscv_cpu_mmu_index(CPURISCVState *env, bool ifetch);
342 hwaddr riscv_cpu_get_phys_page_debug(CPUState *cpu, vaddr addr);
343 void  riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
344                                     MMUAccessType access_type, int mmu_idx,
345                                     uintptr_t retaddr);
346 bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
347                         MMUAccessType access_type, int mmu_idx,
348                         bool probe, uintptr_t retaddr);
349 void riscv_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr,
350                                      vaddr addr, unsigned size,
351                                      MMUAccessType access_type,
352                                      int mmu_idx, MemTxAttrs attrs,
353                                      MemTxResult response, uintptr_t retaddr);
354 char *riscv_isa_string(RISCVCPU *cpu);
355 void riscv_cpu_list(void);
356 
357 #define cpu_signal_handler riscv_cpu_signal_handler
358 #define cpu_list riscv_cpu_list
359 #define cpu_mmu_index riscv_cpu_mmu_index
360 
361 #ifndef CONFIG_USER_ONLY
362 void riscv_cpu_swap_hypervisor_regs(CPURISCVState *env);
363 int riscv_cpu_claim_interrupts(RISCVCPU *cpu, uint32_t interrupts);
364 uint32_t riscv_cpu_update_mip(RISCVCPU *cpu, uint32_t mask, uint32_t value);
365 #define BOOL_TO_MASK(x) (-!!(x)) /* helper for riscv_cpu_update_mip value */
366 void riscv_cpu_set_rdtime_fn(CPURISCVState *env, uint64_t (*fn)(uint32_t),
367                              uint32_t arg);
368 #endif
369 void riscv_cpu_set_mode(CPURISCVState *env, target_ulong newpriv);
370 
371 void riscv_translate_init(void);
372 int riscv_cpu_signal_handler(int host_signum, void *pinfo, void *puc);
373 void QEMU_NORETURN riscv_raise_exception(CPURISCVState *env,
374                                          uint32_t exception, uintptr_t pc);
375 
376 target_ulong riscv_cpu_get_fflags(CPURISCVState *env);
377 void riscv_cpu_set_fflags(CPURISCVState *env, target_ulong);
378 
379 #define TB_FLAGS_MMU_MASK   7
380 #define TB_FLAGS_PRIV_MMU_MASK                3
381 #define TB_FLAGS_PRIV_HYP_ACCESS_MASK   (1 << 2)
382 #define TB_FLAGS_MSTATUS_FS MSTATUS_FS
383 
384 typedef CPURISCVState CPUArchState;
385 typedef RISCVCPU ArchCPU;
386 #include "exec/cpu-all.h"
387 
388 FIELD(TB_FLAGS, VL_EQ_VLMAX, 2, 1)
389 FIELD(TB_FLAGS, LMUL, 3, 2)
390 FIELD(TB_FLAGS, SEW, 5, 3)
391 FIELD(TB_FLAGS, VILL, 8, 1)
392 /* Is a Hypervisor instruction load/store allowed? */
393 FIELD(TB_FLAGS, HLSX, 9, 1)
394 
395 bool riscv_cpu_is_32bit(CPURISCVState *env);
396 
397 /*
398  * A simplification for VLMAX
399  * = (1 << LMUL) * VLEN / (8 * (1 << SEW))
400  * = (VLEN << LMUL) / (8 << SEW)
401  * = (VLEN << LMUL) >> (SEW + 3)
402  * = VLEN >> (SEW + 3 - LMUL)
403  */
404 static inline uint32_t vext_get_vlmax(RISCVCPU *cpu, target_ulong vtype)
405 {
406     uint8_t sew, lmul;
407 
408     sew = FIELD_EX64(vtype, VTYPE, VSEW);
409     lmul = FIELD_EX64(vtype, VTYPE, VLMUL);
410     return cpu->cfg.vlen >> (sew + 3 - lmul);
411 }
412 
413 static inline void cpu_get_tb_cpu_state(CPURISCVState *env, target_ulong *pc,
414                                         target_ulong *cs_base, uint32_t *pflags)
415 {
416     uint32_t flags = 0;
417 
418     *pc = env->pc;
419     *cs_base = 0;
420 
421     if (riscv_has_ext(env, RVV)) {
422         uint32_t vlmax = vext_get_vlmax(env_archcpu(env), env->vtype);
423         bool vl_eq_vlmax = (env->vstart == 0) && (vlmax == env->vl);
424         flags = FIELD_DP32(flags, TB_FLAGS, VILL,
425                     FIELD_EX64(env->vtype, VTYPE, VILL));
426         flags = FIELD_DP32(flags, TB_FLAGS, SEW,
427                     FIELD_EX64(env->vtype, VTYPE, VSEW));
428         flags = FIELD_DP32(flags, TB_FLAGS, LMUL,
429                     FIELD_EX64(env->vtype, VTYPE, VLMUL));
430         flags = FIELD_DP32(flags, TB_FLAGS, VL_EQ_VLMAX, vl_eq_vlmax);
431     } else {
432         flags = FIELD_DP32(flags, TB_FLAGS, VILL, 1);
433     }
434 
435 #ifdef CONFIG_USER_ONLY
436     flags |= TB_FLAGS_MSTATUS_FS;
437 #else
438     flags |= cpu_mmu_index(env, 0);
439     if (riscv_cpu_fp_enabled(env)) {
440         flags |= env->mstatus & MSTATUS_FS;
441     }
442 
443     if (riscv_has_ext(env, RVH)) {
444         if (env->priv == PRV_M ||
445             (env->priv == PRV_S && !riscv_cpu_virt_enabled(env)) ||
446             (env->priv == PRV_U && !riscv_cpu_virt_enabled(env) &&
447                 get_field(env->hstatus, HSTATUS_HU))) {
448             flags = FIELD_DP32(flags, TB_FLAGS, HLSX, 1);
449         }
450     }
451 #endif
452 
453     *pflags = flags;
454 }
455 
456 int riscv_csrrw(CPURISCVState *env, int csrno, target_ulong *ret_value,
457                 target_ulong new_value, target_ulong write_mask);
458 int riscv_csrrw_debug(CPURISCVState *env, int csrno, target_ulong *ret_value,
459                       target_ulong new_value, target_ulong write_mask);
460 
461 static inline void riscv_csr_write(CPURISCVState *env, int csrno,
462                                    target_ulong val)
463 {
464     riscv_csrrw(env, csrno, NULL, val, MAKE_64BIT_MASK(0, TARGET_LONG_BITS));
465 }
466 
467 static inline target_ulong riscv_csr_read(CPURISCVState *env, int csrno)
468 {
469     target_ulong val = 0;
470     riscv_csrrw(env, csrno, &val, 0, 0);
471     return val;
472 }
473 
474 typedef int (*riscv_csr_predicate_fn)(CPURISCVState *env, int csrno);
475 typedef int (*riscv_csr_read_fn)(CPURISCVState *env, int csrno,
476     target_ulong *ret_value);
477 typedef int (*riscv_csr_write_fn)(CPURISCVState *env, int csrno,
478     target_ulong new_value);
479 typedef int (*riscv_csr_op_fn)(CPURISCVState *env, int csrno,
480     target_ulong *ret_value, target_ulong new_value, target_ulong write_mask);
481 
482 typedef struct {
483     const char *name;
484     riscv_csr_predicate_fn predicate;
485     riscv_csr_read_fn read;
486     riscv_csr_write_fn write;
487     riscv_csr_op_fn op;
488 } riscv_csr_operations;
489 
490 /* CSR function table constants */
491 enum {
492     CSR_TABLE_SIZE = 0x1000
493 };
494 
495 /* CSR function table */
496 extern riscv_csr_operations csr_ops[CSR_TABLE_SIZE];
497 
498 void riscv_get_csr_ops(int csrno, riscv_csr_operations *ops);
499 void riscv_set_csr_ops(int csrno, riscv_csr_operations *ops);
500 
501 void riscv_cpu_register_gdb_regs_for_features(CPUState *cs);
502 
503 #endif /* RISCV_CPU_H */
504