xref: /openbmc/qemu/target/riscv/cpu.h (revision c0a635f3)
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 sptbr;  /* until: priv-1.9.1 */
167     target_ulong satp;   /* since: priv-1.10.0 */
168     target_ulong sbadaddr;
169     target_ulong mbadaddr;
170     target_ulong medeleg;
171 
172     target_ulong stvec;
173     target_ulong sepc;
174     target_ulong scause;
175 
176     target_ulong mtvec;
177     target_ulong mepc;
178     target_ulong mcause;
179     target_ulong mtval;  /* since: priv-1.10.0 */
180 
181     /* Hypervisor CSRs */
182     target_ulong hstatus;
183     target_ulong hedeleg;
184     target_ulong hideleg;
185     target_ulong hcounteren;
186     target_ulong htval;
187     target_ulong htinst;
188     target_ulong hgatp;
189     uint64_t htimedelta;
190 
191     /* Virtual CSRs */
192     /*
193      * For RV32 this is 32-bit vsstatus and 32-bit vsstatush.
194      * For RV64 this is a 64-bit vsstatus.
195      */
196     uint64_t vsstatus;
197     target_ulong vstvec;
198     target_ulong vsscratch;
199     target_ulong vsepc;
200     target_ulong vscause;
201     target_ulong vstval;
202     target_ulong vsatp;
203 
204     target_ulong mtval2;
205     target_ulong mtinst;
206 
207     /* HS Backup CSRs */
208     target_ulong stvec_hs;
209     target_ulong sscratch_hs;
210     target_ulong sepc_hs;
211     target_ulong scause_hs;
212     target_ulong stval_hs;
213     target_ulong satp_hs;
214     uint64_t mstatus_hs;
215 
216     target_ulong scounteren;
217     target_ulong mcounteren;
218 
219     target_ulong sscratch;
220     target_ulong mscratch;
221 
222     /* temporary htif regs */
223     uint64_t mfromhost;
224     uint64_t mtohost;
225     uint64_t timecmp;
226 
227     /* physical memory protection */
228     pmp_table_t pmp_state;
229 
230     /* machine specific rdtime callback */
231     uint64_t (*rdtime_fn)(uint32_t);
232     uint32_t rdtime_fn_arg;
233 
234     /* True if in debugger mode.  */
235     bool debugger;
236 #endif
237 
238     float_status fp_status;
239 
240     /* Fields from here on are preserved across CPU reset. */
241     QEMUTimer *timer; /* Internal timer */
242 };
243 
244 OBJECT_DECLARE_TYPE(RISCVCPU, RISCVCPUClass,
245                     RISCV_CPU)
246 
247 /**
248  * RISCVCPUClass:
249  * @parent_realize: The parent class' realize handler.
250  * @parent_reset: The parent class' reset handler.
251  *
252  * A RISCV CPU model.
253  */
254 struct RISCVCPUClass {
255     /*< private >*/
256     CPUClass parent_class;
257     /*< public >*/
258     DeviceRealize parent_realize;
259     DeviceReset parent_reset;
260 };
261 
262 /**
263  * RISCVCPU:
264  * @env: #CPURISCVState
265  *
266  * A RISCV CPU.
267  */
268 struct RISCVCPU {
269     /*< private >*/
270     CPUState parent_obj;
271     /*< public >*/
272     CPUNegativeOffsetState neg;
273     CPURISCVState env;
274 
275     /* Configuration Settings */
276     struct {
277         bool ext_i;
278         bool ext_e;
279         bool ext_g;
280         bool ext_m;
281         bool ext_a;
282         bool ext_f;
283         bool ext_d;
284         bool ext_c;
285         bool ext_s;
286         bool ext_u;
287         bool ext_h;
288         bool ext_v;
289         bool ext_counters;
290         bool ext_ifencei;
291         bool ext_icsr;
292 
293         char *priv_spec;
294         char *user_spec;
295         char *vext_spec;
296         uint16_t vlen;
297         uint16_t elen;
298         bool mmu;
299         bool pmp;
300         uint64_t resetvec;
301     } cfg;
302 };
303 
304 static inline int riscv_has_ext(CPURISCVState *env, target_ulong ext)
305 {
306     return (env->misa & ext) != 0;
307 }
308 
309 static inline bool riscv_feature(CPURISCVState *env, int feature)
310 {
311     return env->features & (1ULL << feature);
312 }
313 
314 #include "cpu_user.h"
315 #include "cpu_bits.h"
316 
317 extern const char * const riscv_int_regnames[];
318 extern const char * const riscv_fpr_regnames[];
319 extern const char * const riscv_excp_names[];
320 extern const char * const riscv_intr_names[];
321 
322 const char *riscv_cpu_get_trap_name(target_ulong cause, bool async);
323 void riscv_cpu_do_interrupt(CPUState *cpu);
324 int riscv_cpu_gdb_read_register(CPUState *cpu, GByteArray *buf, int reg);
325 int riscv_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);
326 bool riscv_cpu_exec_interrupt(CPUState *cs, int interrupt_request);
327 bool riscv_cpu_fp_enabled(CPURISCVState *env);
328 bool riscv_cpu_virt_enabled(CPURISCVState *env);
329 void riscv_cpu_set_virt_enabled(CPURISCVState *env, bool enable);
330 bool riscv_cpu_force_hs_excep_enabled(CPURISCVState *env);
331 void riscv_cpu_set_force_hs_excep(CPURISCVState *env, bool enable);
332 bool riscv_cpu_two_stage_lookup(int mmu_idx);
333 int riscv_cpu_mmu_index(CPURISCVState *env, bool ifetch);
334 hwaddr riscv_cpu_get_phys_page_debug(CPUState *cpu, vaddr addr);
335 void  riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
336                                     MMUAccessType access_type, int mmu_idx,
337                                     uintptr_t retaddr);
338 bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
339                         MMUAccessType access_type, int mmu_idx,
340                         bool probe, uintptr_t retaddr);
341 void riscv_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr,
342                                      vaddr addr, unsigned size,
343                                      MMUAccessType access_type,
344                                      int mmu_idx, MemTxAttrs attrs,
345                                      MemTxResult response, uintptr_t retaddr);
346 char *riscv_isa_string(RISCVCPU *cpu);
347 void riscv_cpu_list(void);
348 
349 #define cpu_signal_handler riscv_cpu_signal_handler
350 #define cpu_list riscv_cpu_list
351 #define cpu_mmu_index riscv_cpu_mmu_index
352 
353 #ifndef CONFIG_USER_ONLY
354 void riscv_cpu_swap_hypervisor_regs(CPURISCVState *env);
355 int riscv_cpu_claim_interrupts(RISCVCPU *cpu, uint32_t interrupts);
356 uint32_t riscv_cpu_update_mip(RISCVCPU *cpu, uint32_t mask, uint32_t value);
357 #define BOOL_TO_MASK(x) (-!!(x)) /* helper for riscv_cpu_update_mip value */
358 void riscv_cpu_set_rdtime_fn(CPURISCVState *env, uint64_t (*fn)(uint32_t),
359                              uint32_t arg);
360 #endif
361 void riscv_cpu_set_mode(CPURISCVState *env, target_ulong newpriv);
362 
363 void riscv_translate_init(void);
364 int riscv_cpu_signal_handler(int host_signum, void *pinfo, void *puc);
365 void QEMU_NORETURN riscv_raise_exception(CPURISCVState *env,
366                                          uint32_t exception, uintptr_t pc);
367 
368 target_ulong riscv_cpu_get_fflags(CPURISCVState *env);
369 void riscv_cpu_set_fflags(CPURISCVState *env, target_ulong);
370 
371 #define TB_FLAGS_MMU_MASK   7
372 #define TB_FLAGS_PRIV_MMU_MASK                3
373 #define TB_FLAGS_PRIV_HYP_ACCESS_MASK   (1 << 2)
374 #define TB_FLAGS_MSTATUS_FS MSTATUS_FS
375 
376 typedef CPURISCVState CPUArchState;
377 typedef RISCVCPU ArchCPU;
378 #include "exec/cpu-all.h"
379 
380 FIELD(TB_FLAGS, VL_EQ_VLMAX, 2, 1)
381 FIELD(TB_FLAGS, LMUL, 3, 2)
382 FIELD(TB_FLAGS, SEW, 5, 3)
383 FIELD(TB_FLAGS, VILL, 8, 1)
384 /* Is a Hypervisor instruction load/store allowed? */
385 FIELD(TB_FLAGS, HLSX, 9, 1)
386 
387 /*
388  * A simplification for VLMAX
389  * = (1 << LMUL) * VLEN / (8 * (1 << SEW))
390  * = (VLEN << LMUL) / (8 << SEW)
391  * = (VLEN << LMUL) >> (SEW + 3)
392  * = VLEN >> (SEW + 3 - LMUL)
393  */
394 static inline uint32_t vext_get_vlmax(RISCVCPU *cpu, target_ulong vtype)
395 {
396     uint8_t sew, lmul;
397 
398     sew = FIELD_EX64(vtype, VTYPE, VSEW);
399     lmul = FIELD_EX64(vtype, VTYPE, VLMUL);
400     return cpu->cfg.vlen >> (sew + 3 - lmul);
401 }
402 
403 static inline void cpu_get_tb_cpu_state(CPURISCVState *env, target_ulong *pc,
404                                         target_ulong *cs_base, uint32_t *pflags)
405 {
406     uint32_t flags = 0;
407 
408     *pc = env->pc;
409     *cs_base = 0;
410 
411     if (riscv_has_ext(env, RVV)) {
412         uint32_t vlmax = vext_get_vlmax(env_archcpu(env), env->vtype);
413         bool vl_eq_vlmax = (env->vstart == 0) && (vlmax == env->vl);
414         flags = FIELD_DP32(flags, TB_FLAGS, VILL,
415                     FIELD_EX64(env->vtype, VTYPE, VILL));
416         flags = FIELD_DP32(flags, TB_FLAGS, SEW,
417                     FIELD_EX64(env->vtype, VTYPE, VSEW));
418         flags = FIELD_DP32(flags, TB_FLAGS, LMUL,
419                     FIELD_EX64(env->vtype, VTYPE, VLMUL));
420         flags = FIELD_DP32(flags, TB_FLAGS, VL_EQ_VLMAX, vl_eq_vlmax);
421     } else {
422         flags = FIELD_DP32(flags, TB_FLAGS, VILL, 1);
423     }
424 
425 #ifdef CONFIG_USER_ONLY
426     flags |= TB_FLAGS_MSTATUS_FS;
427 #else
428     flags |= cpu_mmu_index(env, 0);
429     if (riscv_cpu_fp_enabled(env)) {
430         flags |= env->mstatus & MSTATUS_FS;
431     }
432 
433     if (riscv_has_ext(env, RVH)) {
434         if (env->priv == PRV_M ||
435             (env->priv == PRV_S && !riscv_cpu_virt_enabled(env)) ||
436             (env->priv == PRV_U && !riscv_cpu_virt_enabled(env) &&
437                 get_field(env->hstatus, HSTATUS_HU))) {
438             flags = FIELD_DP32(flags, TB_FLAGS, HLSX, 1);
439         }
440     }
441 #endif
442 
443     *pflags = flags;
444 }
445 
446 int riscv_csrrw(CPURISCVState *env, int csrno, target_ulong *ret_value,
447                 target_ulong new_value, target_ulong write_mask);
448 int riscv_csrrw_debug(CPURISCVState *env, int csrno, target_ulong *ret_value,
449                       target_ulong new_value, target_ulong write_mask);
450 
451 static inline void riscv_csr_write(CPURISCVState *env, int csrno,
452                                    target_ulong val)
453 {
454     riscv_csrrw(env, csrno, NULL, val, MAKE_64BIT_MASK(0, TARGET_LONG_BITS));
455 }
456 
457 static inline target_ulong riscv_csr_read(CPURISCVState *env, int csrno)
458 {
459     target_ulong val = 0;
460     riscv_csrrw(env, csrno, &val, 0, 0);
461     return val;
462 }
463 
464 typedef int (*riscv_csr_predicate_fn)(CPURISCVState *env, int csrno);
465 typedef int (*riscv_csr_read_fn)(CPURISCVState *env, int csrno,
466     target_ulong *ret_value);
467 typedef int (*riscv_csr_write_fn)(CPURISCVState *env, int csrno,
468     target_ulong new_value);
469 typedef int (*riscv_csr_op_fn)(CPURISCVState *env, int csrno,
470     target_ulong *ret_value, target_ulong new_value, target_ulong write_mask);
471 
472 typedef struct {
473     riscv_csr_predicate_fn predicate;
474     riscv_csr_read_fn read;
475     riscv_csr_write_fn write;
476     riscv_csr_op_fn op;
477 } riscv_csr_operations;
478 
479 void riscv_get_csr_ops(int csrno, riscv_csr_operations *ops);
480 void riscv_set_csr_ops(int csrno, riscv_csr_operations *ops);
481 
482 void riscv_cpu_register_gdb_regs_for_features(CPUState *cs);
483 
484 #endif /* RISCV_CPU_H */
485