xref: /openbmc/qemu/target/riscv/cpu.h (revision b3c818a4)
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     char *dyn_csr_xml;
276 
277     /* Configuration Settings */
278     struct {
279         bool ext_i;
280         bool ext_e;
281         bool ext_g;
282         bool ext_m;
283         bool ext_a;
284         bool ext_f;
285         bool ext_d;
286         bool ext_c;
287         bool ext_s;
288         bool ext_u;
289         bool ext_h;
290         bool ext_v;
291         bool ext_counters;
292         bool ext_ifencei;
293         bool ext_icsr;
294 
295         char *priv_spec;
296         char *user_spec;
297         char *vext_spec;
298         uint16_t vlen;
299         uint16_t elen;
300         bool mmu;
301         bool pmp;
302         uint64_t resetvec;
303     } cfg;
304 };
305 
306 static inline int riscv_has_ext(CPURISCVState *env, target_ulong ext)
307 {
308     return (env->misa & ext) != 0;
309 }
310 
311 static inline bool riscv_feature(CPURISCVState *env, int feature)
312 {
313     return env->features & (1ULL << feature);
314 }
315 
316 #include "cpu_user.h"
317 #include "cpu_bits.h"
318 
319 extern const char * const riscv_int_regnames[];
320 extern const char * const riscv_fpr_regnames[];
321 extern const char * const riscv_excp_names[];
322 extern const char * const riscv_intr_names[];
323 
324 const char *riscv_cpu_get_trap_name(target_ulong cause, bool async);
325 void riscv_cpu_do_interrupt(CPUState *cpu);
326 int riscv_cpu_gdb_read_register(CPUState *cpu, GByteArray *buf, int reg);
327 int riscv_cpu_gdb_write_register(CPUState *cpu, uint8_t *buf, int reg);
328 bool riscv_cpu_exec_interrupt(CPUState *cs, int interrupt_request);
329 bool riscv_cpu_fp_enabled(CPURISCVState *env);
330 bool riscv_cpu_virt_enabled(CPURISCVState *env);
331 void riscv_cpu_set_virt_enabled(CPURISCVState *env, bool enable);
332 bool riscv_cpu_force_hs_excep_enabled(CPURISCVState *env);
333 void riscv_cpu_set_force_hs_excep(CPURISCVState *env, bool enable);
334 bool riscv_cpu_two_stage_lookup(int mmu_idx);
335 int riscv_cpu_mmu_index(CPURISCVState *env, bool ifetch);
336 hwaddr riscv_cpu_get_phys_page_debug(CPUState *cpu, vaddr addr);
337 void  riscv_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
338                                     MMUAccessType access_type, int mmu_idx,
339                                     uintptr_t retaddr);
340 bool riscv_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
341                         MMUAccessType access_type, int mmu_idx,
342                         bool probe, uintptr_t retaddr);
343 void riscv_cpu_do_transaction_failed(CPUState *cs, hwaddr physaddr,
344                                      vaddr addr, unsigned size,
345                                      MMUAccessType access_type,
346                                      int mmu_idx, MemTxAttrs attrs,
347                                      MemTxResult response, uintptr_t retaddr);
348 char *riscv_isa_string(RISCVCPU *cpu);
349 void riscv_cpu_list(void);
350 
351 #define cpu_signal_handler riscv_cpu_signal_handler
352 #define cpu_list riscv_cpu_list
353 #define cpu_mmu_index riscv_cpu_mmu_index
354 
355 #ifndef CONFIG_USER_ONLY
356 void riscv_cpu_swap_hypervisor_regs(CPURISCVState *env);
357 int riscv_cpu_claim_interrupts(RISCVCPU *cpu, uint32_t interrupts);
358 uint32_t riscv_cpu_update_mip(RISCVCPU *cpu, uint32_t mask, uint32_t value);
359 #define BOOL_TO_MASK(x) (-!!(x)) /* helper for riscv_cpu_update_mip value */
360 void riscv_cpu_set_rdtime_fn(CPURISCVState *env, uint64_t (*fn)(uint32_t),
361                              uint32_t arg);
362 #endif
363 void riscv_cpu_set_mode(CPURISCVState *env, target_ulong newpriv);
364 
365 void riscv_translate_init(void);
366 int riscv_cpu_signal_handler(int host_signum, void *pinfo, void *puc);
367 void QEMU_NORETURN riscv_raise_exception(CPURISCVState *env,
368                                          uint32_t exception, uintptr_t pc);
369 
370 target_ulong riscv_cpu_get_fflags(CPURISCVState *env);
371 void riscv_cpu_set_fflags(CPURISCVState *env, target_ulong);
372 
373 #define TB_FLAGS_MMU_MASK   7
374 #define TB_FLAGS_PRIV_MMU_MASK                3
375 #define TB_FLAGS_PRIV_HYP_ACCESS_MASK   (1 << 2)
376 #define TB_FLAGS_MSTATUS_FS MSTATUS_FS
377 
378 typedef CPURISCVState CPUArchState;
379 typedef RISCVCPU ArchCPU;
380 #include "exec/cpu-all.h"
381 
382 FIELD(TB_FLAGS, VL_EQ_VLMAX, 2, 1)
383 FIELD(TB_FLAGS, LMUL, 3, 2)
384 FIELD(TB_FLAGS, SEW, 5, 3)
385 FIELD(TB_FLAGS, VILL, 8, 1)
386 /* Is a Hypervisor instruction load/store allowed? */
387 FIELD(TB_FLAGS, HLSX, 9, 1)
388 
389 bool riscv_cpu_is_32bit(CPURISCVState *env);
390 
391 /*
392  * A simplification for VLMAX
393  * = (1 << LMUL) * VLEN / (8 * (1 << SEW))
394  * = (VLEN << LMUL) / (8 << SEW)
395  * = (VLEN << LMUL) >> (SEW + 3)
396  * = VLEN >> (SEW + 3 - LMUL)
397  */
398 static inline uint32_t vext_get_vlmax(RISCVCPU *cpu, target_ulong vtype)
399 {
400     uint8_t sew, lmul;
401 
402     sew = FIELD_EX64(vtype, VTYPE, VSEW);
403     lmul = FIELD_EX64(vtype, VTYPE, VLMUL);
404     return cpu->cfg.vlen >> (sew + 3 - lmul);
405 }
406 
407 static inline void cpu_get_tb_cpu_state(CPURISCVState *env, target_ulong *pc,
408                                         target_ulong *cs_base, uint32_t *pflags)
409 {
410     uint32_t flags = 0;
411 
412     *pc = env->pc;
413     *cs_base = 0;
414 
415     if (riscv_has_ext(env, RVV)) {
416         uint32_t vlmax = vext_get_vlmax(env_archcpu(env), env->vtype);
417         bool vl_eq_vlmax = (env->vstart == 0) && (vlmax == env->vl);
418         flags = FIELD_DP32(flags, TB_FLAGS, VILL,
419                     FIELD_EX64(env->vtype, VTYPE, VILL));
420         flags = FIELD_DP32(flags, TB_FLAGS, SEW,
421                     FIELD_EX64(env->vtype, VTYPE, VSEW));
422         flags = FIELD_DP32(flags, TB_FLAGS, LMUL,
423                     FIELD_EX64(env->vtype, VTYPE, VLMUL));
424         flags = FIELD_DP32(flags, TB_FLAGS, VL_EQ_VLMAX, vl_eq_vlmax);
425     } else {
426         flags = FIELD_DP32(flags, TB_FLAGS, VILL, 1);
427     }
428 
429 #ifdef CONFIG_USER_ONLY
430     flags |= TB_FLAGS_MSTATUS_FS;
431 #else
432     flags |= cpu_mmu_index(env, 0);
433     if (riscv_cpu_fp_enabled(env)) {
434         flags |= env->mstatus & MSTATUS_FS;
435     }
436 
437     if (riscv_has_ext(env, RVH)) {
438         if (env->priv == PRV_M ||
439             (env->priv == PRV_S && !riscv_cpu_virt_enabled(env)) ||
440             (env->priv == PRV_U && !riscv_cpu_virt_enabled(env) &&
441                 get_field(env->hstatus, HSTATUS_HU))) {
442             flags = FIELD_DP32(flags, TB_FLAGS, HLSX, 1);
443         }
444     }
445 #endif
446 
447     *pflags = flags;
448 }
449 
450 int riscv_csrrw(CPURISCVState *env, int csrno, target_ulong *ret_value,
451                 target_ulong new_value, target_ulong write_mask);
452 int riscv_csrrw_debug(CPURISCVState *env, int csrno, target_ulong *ret_value,
453                       target_ulong new_value, target_ulong write_mask);
454 
455 static inline void riscv_csr_write(CPURISCVState *env, int csrno,
456                                    target_ulong val)
457 {
458     riscv_csrrw(env, csrno, NULL, val, MAKE_64BIT_MASK(0, TARGET_LONG_BITS));
459 }
460 
461 static inline target_ulong riscv_csr_read(CPURISCVState *env, int csrno)
462 {
463     target_ulong val = 0;
464     riscv_csrrw(env, csrno, &val, 0, 0);
465     return val;
466 }
467 
468 typedef int (*riscv_csr_predicate_fn)(CPURISCVState *env, int csrno);
469 typedef int (*riscv_csr_read_fn)(CPURISCVState *env, int csrno,
470     target_ulong *ret_value);
471 typedef int (*riscv_csr_write_fn)(CPURISCVState *env, int csrno,
472     target_ulong new_value);
473 typedef int (*riscv_csr_op_fn)(CPURISCVState *env, int csrno,
474     target_ulong *ret_value, target_ulong new_value, target_ulong write_mask);
475 
476 typedef struct {
477     const char *name;
478     riscv_csr_predicate_fn predicate;
479     riscv_csr_read_fn read;
480     riscv_csr_write_fn write;
481     riscv_csr_op_fn op;
482 } riscv_csr_operations;
483 
484 /* CSR function table constants */
485 enum {
486     CSR_TABLE_SIZE = 0x1000
487 };
488 
489 /* CSR function table */
490 extern riscv_csr_operations csr_ops[];
491 
492 void riscv_get_csr_ops(int csrno, riscv_csr_operations *ops);
493 void riscv_set_csr_ops(int csrno, riscv_csr_operations *ops);
494 
495 void riscv_cpu_register_gdb_regs_for_features(CPUState *cs);
496 
497 #endif /* RISCV_CPU_H */
498