xref: /openbmc/qemu/target/ppc/compat.c (revision bc5c4f21)
1 /*
2  *  PowerPC CPU initialization for qemu.
3  *
4  *  Copyright 2016, David Gibson, Red Hat Inc. <dgibson@redhat.com>
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 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 "sysemu/hw_accel.h"
22 #include "sysemu/kvm.h"
23 #include "kvm_ppc.h"
24 #include "sysemu/cpus.h"
25 #include "qemu/error-report.h"
26 #include "qapi/error.h"
27 #include "cpu-models.h"
28 
29 typedef struct {
30     uint32_t pvr;
31     uint64_t pcr;
32     uint64_t pcr_level;
33     int max_threads;
34 } CompatInfo;
35 
36 static const CompatInfo compat_table[] = {
37     /*
38      * Ordered from oldest to newest - the code relies on this
39      */
40     { /* POWER6, ISA2.05 */
41         .pvr = CPU_POWERPC_LOGICAL_2_05,
42         .pcr = PCR_COMPAT_2_07 | PCR_COMPAT_2_06 | PCR_COMPAT_2_05
43                | PCR_TM_DIS | PCR_VSX_DIS,
44         .pcr_level = PCR_COMPAT_2_05,
45         .max_threads = 2,
46     },
47     { /* POWER7, ISA2.06 */
48         .pvr = CPU_POWERPC_LOGICAL_2_06,
49         .pcr = PCR_COMPAT_2_07 | PCR_COMPAT_2_06 | PCR_TM_DIS,
50         .pcr_level = PCR_COMPAT_2_06,
51         .max_threads = 4,
52     },
53     {
54         .pvr = CPU_POWERPC_LOGICAL_2_06_PLUS,
55         .pcr = PCR_COMPAT_2_07 | PCR_COMPAT_2_06 | PCR_TM_DIS,
56         .pcr_level = PCR_COMPAT_2_06,
57         .max_threads = 4,
58     },
59     { /* POWER8, ISA2.07 */
60         .pvr = CPU_POWERPC_LOGICAL_2_07,
61         .pcr = PCR_COMPAT_2_07,
62         .pcr_level = PCR_COMPAT_2_07,
63         .max_threads = 8,
64     },
65 };
66 
67 static const CompatInfo *compat_by_pvr(uint32_t pvr)
68 {
69     int i;
70 
71     for (i = 0; i < ARRAY_SIZE(compat_table); i++) {
72         if (compat_table[i].pvr == pvr) {
73             return &compat_table[i];
74         }
75     }
76     return NULL;
77 }
78 
79 bool ppc_check_compat(PowerPCCPU *cpu, uint32_t compat_pvr,
80                       uint32_t min_compat_pvr, uint32_t max_compat_pvr)
81 {
82     PowerPCCPUClass *pcc = POWERPC_CPU_GET_CLASS(cpu);
83     const CompatInfo *compat = compat_by_pvr(compat_pvr);
84     const CompatInfo *min = compat_by_pvr(min_compat_pvr);
85     const CompatInfo *max = compat_by_pvr(max_compat_pvr);
86 
87 #if !defined(CONFIG_USER_ONLY)
88     g_assert(cpu->vhyp);
89 #endif
90     g_assert(!min_compat_pvr || min);
91     g_assert(!max_compat_pvr || max);
92 
93     if (!compat) {
94         /* Not a recognized logical PVR */
95         return false;
96     }
97     if ((min && (compat < min)) || (max && (compat > max))) {
98         /* Outside specified range */
99         return false;
100     }
101     if (!(pcc->pcr_supported & compat->pcr_level)) {
102         /* Not supported by this CPU */
103         return false;
104     }
105     return true;
106 }
107 
108 void ppc_set_compat(PowerPCCPU *cpu, uint32_t compat_pvr, Error **errp)
109 {
110     const CompatInfo *compat = compat_by_pvr(compat_pvr);
111     CPUPPCState *env = &cpu->env;
112     PowerPCCPUClass *pcc = POWERPC_CPU_GET_CLASS(cpu);
113     uint64_t pcr;
114 
115     if (!compat_pvr) {
116         pcr = 0;
117     } else if (!compat) {
118         error_setg(errp, "Unknown compatibility PVR 0x%08"PRIx32, compat_pvr);
119         return;
120     } else if (!ppc_check_compat(cpu, compat_pvr, 0, 0)) {
121         error_setg(errp, "Compatibility PVR 0x%08"PRIx32" not valid for CPU",
122                    compat_pvr);
123         return;
124     } else {
125         pcr = compat->pcr;
126     }
127 
128     cpu_synchronize_state(CPU(cpu));
129 
130     cpu->compat_pvr = compat_pvr;
131     env->spr[SPR_PCR] = pcr & pcc->pcr_mask;
132 
133     if (kvm_enabled()) {
134         int ret = kvmppc_set_compat(cpu, cpu->compat_pvr);
135         if (ret < 0) {
136             error_setg_errno(errp, -ret,
137                              "Unable to set CPU compatibility mode in KVM");
138         }
139     }
140 }
141 
142 typedef struct {
143     uint32_t compat_pvr;
144     Error *err;
145 } SetCompatState;
146 
147 static void do_set_compat(CPUState *cs, run_on_cpu_data arg)
148 {
149     PowerPCCPU *cpu = POWERPC_CPU(cs);
150     SetCompatState *s = arg.host_ptr;
151 
152     ppc_set_compat(cpu, s->compat_pvr, &s->err);
153 }
154 
155 void ppc_set_compat_all(uint32_t compat_pvr, Error **errp)
156 {
157     CPUState *cs;
158 
159     CPU_FOREACH(cs) {
160         SetCompatState s = {
161             .compat_pvr = compat_pvr,
162             .err = NULL,
163         };
164 
165         run_on_cpu(cs, do_set_compat, RUN_ON_CPU_HOST_PTR(&s));
166 
167         if (s.err) {
168             error_propagate(errp, s.err);
169             return;
170         }
171     }
172 }
173 
174 int ppc_compat_max_threads(PowerPCCPU *cpu)
175 {
176     const CompatInfo *compat = compat_by_pvr(cpu->compat_pvr);
177     int n_threads = CPU(cpu)->nr_threads;
178 
179     if (cpu->compat_pvr) {
180         g_assert(compat);
181         n_threads = MIN(n_threads, compat->max_threads);
182     }
183 
184     return n_threads;
185 }
186