xref: /openbmc/qemu/target/loongarch/tcg/op_helper.c (revision 2e1cacfb)
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * LoongArch emulation helpers for QEMU.
4  *
5  * Copyright (c) 2021 Loongson Technology Corporation Limited
6  */
7 
8 #include "qemu/osdep.h"
9 #include "qemu/log.h"
10 #include "cpu.h"
11 #include "qemu/host-utils.h"
12 #include "exec/helper-proto.h"
13 #include "exec/exec-all.h"
14 #include "exec/cpu_ldst.h"
15 #include "internals.h"
16 #include "qemu/crc32c.h"
17 #include <zlib.h> /* for crc32 */
18 #include "cpu-csr.h"
19 
20 /* Exceptions helpers */
21 void helper_raise_exception(CPULoongArchState *env, uint32_t exception)
22 {
23     do_raise_exception(env, exception, GETPC());
24 }
25 
26 target_ulong helper_bitrev_w(target_ulong rj)
27 {
28     return (int32_t)revbit32(rj);
29 }
30 
31 target_ulong helper_bitrev_d(target_ulong rj)
32 {
33     return revbit64(rj);
34 }
35 
36 target_ulong helper_bitswap(target_ulong v)
37 {
38     v = ((v >> 1) & (target_ulong)0x5555555555555555ULL) |
39         ((v & (target_ulong)0x5555555555555555ULL) << 1);
40     v = ((v >> 2) & (target_ulong)0x3333333333333333ULL) |
41         ((v & (target_ulong)0x3333333333333333ULL) << 2);
42     v = ((v >> 4) & (target_ulong)0x0F0F0F0F0F0F0F0FULL) |
43         ((v & (target_ulong)0x0F0F0F0F0F0F0F0FULL) << 4);
44     return v;
45 }
46 
47 /* loongarch assert op */
48 void helper_asrtle_d(CPULoongArchState *env, target_ulong rj, target_ulong rk)
49 {
50     if (rj > rk) {
51         env->CSR_BADV = rj;
52         do_raise_exception(env, EXCCODE_BCE, GETPC());
53     }
54 }
55 
56 void helper_asrtgt_d(CPULoongArchState *env, target_ulong rj, target_ulong rk)
57 {
58     if (rj <= rk) {
59         env->CSR_BADV = rj;
60         do_raise_exception(env, EXCCODE_BCE, GETPC());
61     }
62 }
63 
64 target_ulong helper_crc32(target_ulong val, target_ulong m, uint64_t sz)
65 {
66     uint8_t buf[8];
67     target_ulong mask = ((sz * 8) == 64) ? -1ULL : ((1ULL << (sz * 8)) - 1);
68 
69     m &= mask;
70     stq_le_p(buf, m);
71     return (int32_t) (crc32(val ^ 0xffffffff, buf, sz) ^ 0xffffffff);
72 }
73 
74 target_ulong helper_crc32c(target_ulong val, target_ulong m, uint64_t sz)
75 {
76     uint8_t buf[8];
77     target_ulong mask = ((sz * 8) == 64) ? -1ULL : ((1ULL << (sz * 8)) - 1);
78     m &= mask;
79     stq_le_p(buf, m);
80     return (int32_t) (crc32c(val, buf, sz) ^ 0xffffffff);
81 }
82 
83 target_ulong helper_cpucfg(CPULoongArchState *env, target_ulong rj)
84 {
85     return rj >= ARRAY_SIZE(env->cpucfg) ? 0 : env->cpucfg[rj];
86 }
87 
88 uint64_t helper_rdtime_d(CPULoongArchState *env)
89 {
90 #ifdef CONFIG_USER_ONLY
91     return cpu_get_host_ticks();
92 #else
93     uint64_t plv;
94     LoongArchCPU *cpu = env_archcpu(env);
95 
96     plv = FIELD_EX64(env->CSR_CRMD, CSR_CRMD, PLV);
97     if (extract64(env->CSR_MISC, R_CSR_MISC_DRDTL_SHIFT + plv, 1)) {
98         do_raise_exception(env, EXCCODE_IPE, GETPC());
99     }
100 
101     return cpu_loongarch_get_constant_timer_counter(cpu);
102 #endif
103 }
104 
105 #ifndef CONFIG_USER_ONLY
106 void helper_ertn(CPULoongArchState *env)
107 {
108     uint64_t csr_pplv, csr_pie;
109     if (FIELD_EX64(env->CSR_TLBRERA, CSR_TLBRERA, ISTLBR)) {
110         csr_pplv = FIELD_EX64(env->CSR_TLBRPRMD, CSR_TLBRPRMD, PPLV);
111         csr_pie = FIELD_EX64(env->CSR_TLBRPRMD, CSR_TLBRPRMD, PIE);
112 
113         env->CSR_TLBRERA = FIELD_DP64(env->CSR_TLBRERA, CSR_TLBRERA, ISTLBR, 0);
114         env->CSR_CRMD = FIELD_DP64(env->CSR_CRMD, CSR_CRMD, DA, 0);
115         env->CSR_CRMD = FIELD_DP64(env->CSR_CRMD, CSR_CRMD, PG, 1);
116         set_pc(env, env->CSR_TLBRERA);
117         qemu_log_mask(CPU_LOG_INT, "%s: TLBRERA " TARGET_FMT_lx "\n",
118                       __func__, env->CSR_TLBRERA);
119     } else {
120         csr_pplv = FIELD_EX64(env->CSR_PRMD, CSR_PRMD, PPLV);
121         csr_pie = FIELD_EX64(env->CSR_PRMD, CSR_PRMD, PIE);
122 
123         set_pc(env, env->CSR_ERA);
124         qemu_log_mask(CPU_LOG_INT, "%s: ERA " TARGET_FMT_lx "\n",
125                       __func__, env->CSR_ERA);
126     }
127     env->CSR_CRMD = FIELD_DP64(env->CSR_CRMD, CSR_CRMD, PLV, csr_pplv);
128     env->CSR_CRMD = FIELD_DP64(env->CSR_CRMD, CSR_CRMD, IE, csr_pie);
129 
130     env->lladdr = 1;
131 }
132 
133 void helper_idle(CPULoongArchState *env)
134 {
135     CPUState *cs = env_cpu(env);
136 
137     cs->halted = 1;
138     do_raise_exception(env, EXCP_HLT, 0);
139 }
140 #endif
141