xref: /openbmc/qemu/target/riscv/internals.h (revision 2525edd8)
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 /* share data between vector helpers and decode code */
25 FIELD(VDATA, VM, 0, 1)
26 FIELD(VDATA, LMUL, 1, 3)
27 FIELD(VDATA, NF, 4, 4)
28 FIELD(VDATA, WD, 4, 1)
29 
30 /* float point classify helpers */
31 target_ulong fclass_h(uint64_t frs1);
32 target_ulong fclass_s(uint64_t frs1);
33 target_ulong fclass_d(uint64_t frs1);
34 
35 #ifndef CONFIG_USER_ONLY
36 extern const VMStateDescription vmstate_riscv_cpu;
37 #endif
38 
39 enum {
40     RISCV_FRM_RNE = 0,  /* Round to Nearest, ties to Even */
41     RISCV_FRM_RTZ = 1,  /* Round towards Zero */
42     RISCV_FRM_RDN = 2,  /* Round Down */
43     RISCV_FRM_RUP = 3,  /* Round Up */
44     RISCV_FRM_RMM = 4,  /* Round to Nearest, ties to Max Magnitude */
45     RISCV_FRM_DYN = 7,  /* Dynamic rounding mode */
46     RISCV_FRM_ROD = 8,  /* Round to Odd */
47 };
48 
49 static inline uint64_t nanbox_s(CPURISCVState *env, float32 f)
50 {
51     /* the value is sign-extended instead of NaN-boxing for zfinx */
52     if (RISCV_CPU(env_cpu(env))->cfg.ext_zfinx) {
53         return (int32_t)f;
54     } else {
55         return f | MAKE_64BIT_MASK(32, 32);
56     }
57 }
58 
59 static inline float32 check_nanbox_s(CPURISCVState *env, uint64_t f)
60 {
61     /* Disable NaN-boxing check when enable zfinx */
62     if (RISCV_CPU(env_cpu(env))->cfg.ext_zfinx) {
63         return (uint32_t)f;
64     }
65 
66     uint64_t mask = MAKE_64BIT_MASK(32, 32);
67 
68     if (likely((f & mask) == mask)) {
69         return (uint32_t)f;
70     } else {
71         return 0x7fc00000u; /* default qnan */
72     }
73 }
74 
75 static inline uint64_t nanbox_h(CPURISCVState *env, float16 f)
76 {
77     /* the value is sign-extended instead of NaN-boxing for zfinx */
78     if (RISCV_CPU(env_cpu(env))->cfg.ext_zfinx) {
79         return (int16_t)f;
80     } else {
81         return f | MAKE_64BIT_MASK(16, 48);
82     }
83 }
84 
85 static inline float16 check_nanbox_h(CPURISCVState *env, uint64_t f)
86 {
87     /* Disable nanbox check when enable zfinx */
88     if (RISCV_CPU(env_cpu(env))->cfg.ext_zfinx) {
89         return (uint16_t)f;
90     }
91 
92     uint64_t mask = MAKE_64BIT_MASK(16, 48);
93 
94     if (likely((f & mask) == mask)) {
95         return (uint16_t)f;
96     } else {
97         return 0x7E00u; /* default qnan */
98     }
99 }
100 
101 #endif
102