xref: /qemu/target/ppc/cpu.c (revision fc524567087c2537b5103cdfc1d41e4f442892b6)
1 /*
2  *  PowerPC CPU routines for qemu.
3  *
4  * Copyright (c) 2017 Nikunj A Dadhania, IBM Corporation.
5  *
6  * This library is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * This library is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 #include "qemu/osdep.h"
21 #include "cpu.h"
22 #include "cpu-models.h"
23 #include "cpu-qom.h"
24 #include "exec/log.h"
25 #include "exec/watchpoint.h"
26 #include "fpu/softfloat-helpers.h"
27 #include "mmu-hash64.h"
28 #include "helper_regs.h"
29 #include "system/tcg.h"
30 
cpu_read_xer(const CPUPPCState * env)31 target_ulong cpu_read_xer(const CPUPPCState *env)
32 {
33     if (is_isa300(env)) {
34         return env->xer | (env->so << XER_SO) |
35             (env->ov << XER_OV) | (env->ca << XER_CA) |
36             (env->ov32 << XER_OV32) | (env->ca32 << XER_CA32);
37     }
38 
39     return env->xer | (env->so << XER_SO) | (env->ov << XER_OV) |
40         (env->ca << XER_CA);
41 }
42 
cpu_write_xer(CPUPPCState * env,target_ulong xer)43 void cpu_write_xer(CPUPPCState *env, target_ulong xer)
44 {
45     env->so = (xer >> XER_SO) & 1;
46     env->ov = (xer >> XER_OV) & 1;
47     env->ca = (xer >> XER_CA) & 1;
48     /* write all the flags, while reading back check of isa300 */
49     env->ov32 = (xer >> XER_OV32) & 1;
50     env->ca32 = (xer >> XER_CA32) & 1;
51     env->xer = xer & ~((1ul << XER_SO) |
52                        (1ul << XER_OV) | (1ul << XER_CA) |
53                        (1ul << XER_OV32) | (1ul << XER_CA32));
54 }
55 
ppc_store_vscr(CPUPPCState * env,uint32_t vscr)56 void ppc_store_vscr(CPUPPCState *env, uint32_t vscr)
57 {
58     env->vscr = vscr & ~(1u << VSCR_SAT);
59     /* Which bit we set is completely arbitrary, but clear the rest.  */
60     env->vscr_sat.u64[0] = vscr & (1u << VSCR_SAT);
61     env->vscr_sat.u64[1] = 0;
62     set_flush_to_zero((vscr >> VSCR_NJ) & 1, &env->vec_status);
63     set_flush_inputs_to_zero((vscr >> VSCR_NJ) & 1, &env->vec_status);
64 }
65 
ppc_get_vscr(CPUPPCState * env)66 uint32_t ppc_get_vscr(CPUPPCState *env)
67 {
68     uint32_t sat = (env->vscr_sat.u64[0] | env->vscr_sat.u64[1]) != 0;
69     return env->vscr | (sat << VSCR_SAT);
70 }
71 
ppc_set_cr(CPUPPCState * env,uint64_t cr)72 void ppc_set_cr(CPUPPCState *env, uint64_t cr)
73 {
74     for (int i = 7; i >= 0; i--) {
75         env->crf[i] = cr & 0xf;
76         cr >>= 4;
77     }
78 }
79 
ppc_get_cr(const CPUPPCState * env)80 uint64_t ppc_get_cr(const CPUPPCState *env)
81 {
82     uint64_t cr = 0;
83     for (int i = 0; i < 8; i++) {
84         cr |= (env->crf[i] & 0xf) << (4 * (7 - i));
85     }
86     return cr;
87 }
88 
89 /* GDBstub can read and write MSR... */
ppc_store_msr(CPUPPCState * env,target_ulong value)90 void ppc_store_msr(CPUPPCState *env, target_ulong value)
91 {
92     hreg_store_msr(env, value, 0);
93 }
94 
95 #if !defined(CONFIG_USER_ONLY)
ppc_store_lpcr(PowerPCCPU * cpu,target_ulong val)96 void ppc_store_lpcr(PowerPCCPU *cpu, target_ulong val)
97 {
98     PowerPCCPUClass *pcc = POWERPC_CPU_GET_CLASS(cpu);
99     CPUPPCState *env = &cpu->env;
100 
101     env->spr[SPR_LPCR] = val & pcc->lpcr_mask;
102     /* The gtse bit affects hflags */
103     hreg_compute_hflags(env);
104 
105     ppc_maybe_interrupt(env);
106 }
107 
108 #if defined(TARGET_PPC64)
ppc_update_ciabr(CPUPPCState * env)109 void ppc_update_ciabr(CPUPPCState *env)
110 {
111     CPUState *cs = env_cpu(env);
112     target_ulong ciabr = env->spr[SPR_CIABR];
113     target_ulong ciea, priv;
114 
115     ciea = ciabr & PPC_BITMASK(0, 61);
116     priv = ciabr & PPC_BITMASK(62, 63);
117 
118     if (env->ciabr_breakpoint) {
119         cpu_breakpoint_remove_by_ref(cs, env->ciabr_breakpoint);
120         env->ciabr_breakpoint = NULL;
121     }
122 
123     if (priv) {
124         cpu_breakpoint_insert(cs, ciea, BP_CPU, &env->ciabr_breakpoint);
125     }
126 }
127 
ppc_store_ciabr(CPUPPCState * env,target_ulong val)128 void ppc_store_ciabr(CPUPPCState *env, target_ulong val)
129 {
130     env->spr[SPR_CIABR] = val;
131     ppc_update_ciabr(env);
132 }
133 
ppc_update_daw(CPUPPCState * env,int rid)134 void ppc_update_daw(CPUPPCState *env, int rid)
135 {
136     CPUState *cs = env_cpu(env);
137     int spr_dawr = rid ? SPR_DAWR1 : SPR_DAWR0;
138     int spr_dawrx = rid ? SPR_DAWRX1 : SPR_DAWRX0;
139     target_ulong deaw = env->spr[spr_dawr] & PPC_BITMASK(0, 60);
140     uint32_t dawrx = env->spr[spr_dawrx];
141     int mrd = extract32(dawrx, PPC_BIT_NR(48), 54 - 48);
142     bool dw = extract32(dawrx, PPC_BIT_NR(57), 1);
143     bool dr = extract32(dawrx, PPC_BIT_NR(58), 1);
144     bool hv = extract32(dawrx, PPC_BIT_NR(61), 1);
145     bool sv = extract32(dawrx, PPC_BIT_NR(62), 1);
146     bool pr = extract32(dawrx, PPC_BIT_NR(62), 1);
147     vaddr len;
148     int flags;
149 
150     if (env->dawr_watchpoint[rid]) {
151         cpu_watchpoint_remove_by_ref(cs, env->dawr_watchpoint[rid]);
152         env->dawr_watchpoint[rid] = NULL;
153     }
154 
155     if (!dr && !dw) {
156         return;
157     }
158 
159     if (!hv && !sv && !pr) {
160         return;
161     }
162 
163     len = (mrd + 1) * 8;
164     flags = BP_CPU | BP_STOP_BEFORE_ACCESS;
165     if (dr) {
166         flags |= BP_MEM_READ;
167     }
168     if (dw) {
169         flags |= BP_MEM_WRITE;
170     }
171 
172     cpu_watchpoint_insert(cs, deaw, len, flags, &env->dawr_watchpoint[rid]);
173 }
174 
ppc_store_dawr0(CPUPPCState * env,target_ulong val)175 void ppc_store_dawr0(CPUPPCState *env, target_ulong val)
176 {
177     env->spr[SPR_DAWR0] = val;
178     ppc_update_daw(env, 0);
179 }
180 
ppc_store_dawrx(CPUPPCState * env,uint32_t val,int rid)181 static void ppc_store_dawrx(CPUPPCState *env, uint32_t val, int rid)
182 {
183     int hrammc = extract32(val, PPC_BIT_NR(56), 1);
184 
185     if (hrammc) {
186         /* This might be done with a second watchpoint at the xor of DEAW[0] */
187         qemu_log_mask(LOG_UNIMP, "%s: DAWRX%d[HRAMMC] is unimplemented\n",
188                       __func__, rid);
189     }
190 
191     env->spr[rid ? SPR_DAWRX1 : SPR_DAWRX0] = val;
192     ppc_update_daw(env, rid);
193 }
194 
ppc_store_dawrx0(CPUPPCState * env,uint32_t val)195 void ppc_store_dawrx0(CPUPPCState *env, uint32_t val)
196 {
197     ppc_store_dawrx(env, val, 0);
198 }
199 
ppc_store_dawr1(CPUPPCState * env,target_ulong val)200 void ppc_store_dawr1(CPUPPCState *env, target_ulong val)
201 {
202     env->spr[SPR_DAWR1] = val;
203     ppc_update_daw(env, 1);
204 }
205 
ppc_store_dawrx1(CPUPPCState * env,uint32_t val)206 void ppc_store_dawrx1(CPUPPCState *env, uint32_t val)
207 {
208     ppc_store_dawrx(env, val, 1);
209 }
210 
211 #endif
212 #endif
213 
fpscr_set_rounding_mode(CPUPPCState * env)214 static inline void fpscr_set_rounding_mode(CPUPPCState *env)
215 {
216     int rnd_type;
217 
218     /* Set rounding mode */
219     switch (env->fpscr & FP_RN) {
220     case 0:
221         /* Best approximation (round to nearest) */
222         rnd_type = float_round_nearest_even;
223         break;
224     case 1:
225         /* Smaller magnitude (round toward zero) */
226         rnd_type = float_round_to_zero;
227         break;
228     case 2:
229         /* Round toward +infinite */
230         rnd_type = float_round_up;
231         break;
232     default:
233     case 3:
234         /* Round toward -infinite */
235         rnd_type = float_round_down;
236         break;
237     }
238     set_float_rounding_mode(rnd_type, &env->fp_status);
239 }
240 
ppc_store_fpscr(CPUPPCState * env,target_ulong val)241 void ppc_store_fpscr(CPUPPCState *env, target_ulong val)
242 {
243     val &= FPSCR_MTFS_MASK;
244     if (val & FPSCR_IX) {
245         val |= FP_VX;
246     }
247     if ((val >> FPSCR_XX) & (val >> FPSCR_XE) & 0x1f) {
248         val |= FP_FEX;
249     }
250     env->fpscr = val;
251     env->fp_status.rebias_overflow  = (FP_OE & env->fpscr) ? true : false;
252     env->fp_status.rebias_underflow = (FP_UE & env->fpscr) ? true : false;
253     if (tcg_enabled()) {
254         fpscr_set_rounding_mode(env);
255     }
256 }
257