xref: /openbmc/qemu/target/riscv/internals.h (revision b278b60d)
1 /*
2  * QEMU RISC-V CPU -- internal functions and types
3  *
4  * Copyright (c) 2020 T-Head Semiconductor Co., Ltd. All rights reserved.
5  *
6  * This program is free software; you can redistribute it and/or modify it
7  * under the terms and conditions of the GNU General Public License,
8  * version 2 or later, as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope it will be useful, but WITHOUT
11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
13  * more details.
14  *
15  * You should have received a copy of the GNU General Public License along with
16  * this program.  If not, see <http://www.gnu.org/licenses/>.
17  */
18 
19 #ifndef RISCV_CPU_INTERNALS_H
20 #define RISCV_CPU_INTERNALS_H
21 
22 #include "hw/registerfields.h"
23 
24 /*
25  * The current MMU Modes are:
26  *  - U                 0b000
27  *  - S                 0b001
28  *  - S+SUM             0b010
29  *  - M                 0b011
30  *  - U+2STAGE          0b100
31  *  - S+2STAGE          0b101
32  *  - S+SUM+2STAGE      0b110
33  *  - Shadow stack+U   0b1000
34  *  - Shadow stack+S   0b1001
35  */
36 #define MMUIdx_U            0
37 #define MMUIdx_S            1
38 #define MMUIdx_S_SUM        2
39 #define MMUIdx_M            3
40 #define MMU_2STAGE_BIT      (1 << 2)
41 #define MMU_IDX_SS_WRITE    (1 << 3)
42 
43 static inline int mmuidx_priv(int mmu_idx)
44 {
45     int ret = mmu_idx & 3;
46     if (ret == MMUIdx_S_SUM) {
47         ret = PRV_S;
48     }
49     return ret;
50 }
51 
52 static inline bool mmuidx_sum(int mmu_idx)
53 {
54     return (mmu_idx & 3) == MMUIdx_S_SUM;
55 }
56 
57 static inline bool mmuidx_2stage(int mmu_idx)
58 {
59     return mmu_idx & MMU_2STAGE_BIT;
60 }
61 
62 /* share data between vector helpers and decode code */
63 FIELD(VDATA, VM, 0, 1)
64 FIELD(VDATA, LMUL, 1, 3)
65 FIELD(VDATA, VTA, 4, 1)
66 FIELD(VDATA, VTA_ALL_1S, 5, 1)
67 FIELD(VDATA, VMA, 6, 1)
68 FIELD(VDATA, NF, 7, 4)
69 FIELD(VDATA, WD, 7, 1)
70 
71 /* float point classify helpers */
72 target_ulong fclass_h(uint64_t frs1);
73 target_ulong fclass_s(uint64_t frs1);
74 target_ulong fclass_d(uint64_t frs1);
75 
76 #ifndef CONFIG_USER_ONLY
77 extern const VMStateDescription vmstate_riscv_cpu;
78 #endif
79 
80 enum {
81     RISCV_FRM_RNE = 0,  /* Round to Nearest, ties to Even */
82     RISCV_FRM_RTZ = 1,  /* Round towards Zero */
83     RISCV_FRM_RDN = 2,  /* Round Down */
84     RISCV_FRM_RUP = 3,  /* Round Up */
85     RISCV_FRM_RMM = 4,  /* Round to Nearest, ties to Max Magnitude */
86     RISCV_FRM_DYN = 7,  /* Dynamic rounding mode */
87     RISCV_FRM_ROD = 8,  /* Round to Odd */
88 };
89 
90 static inline uint64_t nanbox_s(CPURISCVState *env, float32 f)
91 {
92     /* the value is sign-extended instead of NaN-boxing for zfinx */
93     if (env_archcpu(env)->cfg.ext_zfinx) {
94         return (int32_t)f;
95     } else {
96         return f | MAKE_64BIT_MASK(32, 32);
97     }
98 }
99 
100 static inline float32 check_nanbox_s(CPURISCVState *env, uint64_t f)
101 {
102     /* Disable NaN-boxing check when enable zfinx */
103     if (env_archcpu(env)->cfg.ext_zfinx) {
104         return (uint32_t)f;
105     }
106 
107     uint64_t mask = MAKE_64BIT_MASK(32, 32);
108 
109     if (likely((f & mask) == mask)) {
110         return (uint32_t)f;
111     } else {
112         return 0x7fc00000u; /* default qnan */
113     }
114 }
115 
116 static inline uint64_t nanbox_h(CPURISCVState *env, float16 f)
117 {
118     /* the value is sign-extended instead of NaN-boxing for zfinx */
119     if (env_archcpu(env)->cfg.ext_zfinx) {
120         return (int16_t)f;
121     } else {
122         return f | MAKE_64BIT_MASK(16, 48);
123     }
124 }
125 
126 static inline float16 check_nanbox_h(CPURISCVState *env, uint64_t f)
127 {
128     /* Disable nanbox check when enable zfinx */
129     if (env_archcpu(env)->cfg.ext_zfinx) {
130         return (uint16_t)f;
131     }
132 
133     uint64_t mask = MAKE_64BIT_MASK(16, 48);
134 
135     if (likely((f & mask) == mask)) {
136         return (uint16_t)f;
137     } else {
138         return 0x7E00u; /* default qnan */
139     }
140 }
141 
142 /* Our implementation of CPUClass::has_work */
143 bool riscv_cpu_has_work(CPUState *cs);
144 
145 #endif
146