target/ppc/compat.c

   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 "qapi/visitor.h"
  28 #include "cpu-models.h"
  29
  30 typedef struct {
  31     const char *name;
  32     uint32_t pvr;
  33     uint64_t pcr;
  34     uint64_t pcr_level;
  35
  36     /*
  37      * Maximum allowed virtual threads per virtual core
  38      *
  39      * This is to stop older guests getting confused by seeing more
  40      * threads than they think the cpu can support.  Usually it's
  41      * equal to the number of threads supported on bare metal
  42      * hardware, but not always (see POWER9).
  43      */
  44     int max_vthreads;
  45 } CompatInfo;
  46
  47 static const CompatInfo compat_table[] = {
  48     /*
  49      * Ordered from oldest to newest - the code relies on this
  50      */
  51     { /* POWER6, ISA2.05 */
  52         .name = "power6",
  53         .pvr = CPU_POWERPC_LOGICAL_2_05,
  54         .pcr = PCR_COMPAT_3_00 | PCR_COMPAT_2_07 | PCR_COMPAT_2_06 |
  55                PCR_COMPAT_2_05 | PCR_TM_DIS | PCR_VSX_DIS,
  56         .pcr_level = PCR_COMPAT_2_05,
  57         .max_vthreads = 2,
  58     },
  59     { /* POWER7, ISA2.06 */
  60         .name = "power7",
  61         .pvr = CPU_POWERPC_LOGICAL_2_06,
  62         .pcr = PCR_COMPAT_3_00 | PCR_COMPAT_2_07 | PCR_COMPAT_2_06 | PCR_TM_DIS,
  63         .pcr_level = PCR_COMPAT_2_06,
  64         .max_vthreads = 4,
  65     },
  66     {
  67         .name = "power7+",
  68         .pvr = CPU_POWERPC_LOGICAL_2_06_PLUS,
  69         .pcr = PCR_COMPAT_3_00 | PCR_COMPAT_2_07 | PCR_COMPAT_2_06 | PCR_TM_DIS,
  70         .pcr_level = PCR_COMPAT_2_06,
  71         .max_vthreads = 4,
  72     },
  73     { /* POWER8, ISA2.07 */
  74         .name = "power8",
  75         .pvr = CPU_POWERPC_LOGICAL_2_07,
  76         .pcr = PCR_COMPAT_3_00 | PCR_COMPAT_2_07,
  77         .pcr_level = PCR_COMPAT_2_07,
  78         .max_vthreads = 8,
  79     },
  80     { /* POWER9, ISA3.00 */
  81         .name = "power9",
  82         .pvr = CPU_POWERPC_LOGICAL_3_00,
  83         .pcr = PCR_COMPAT_3_00,
  84         .pcr_level = PCR_COMPAT_3_00,
  85         /*
  86          * POWER9 hardware only supports 4 threads / core, but this
  87          * limit is for guests.  We need to support 8 vthreads/vcore
  88          * on POWER9 for POWER8 compatibility guests, and it's very
  89          * confusing if half of the threads disappear from the guest
  90          * if it announces it's POWER9 aware at CAS time.
  91          */
  92         .max_vthreads = 8,
  93     },
  94 };
  95
  96 static const CompatInfo *compat_by_pvr(uint32_t pvr)
  97 {
  98     int i;
  99
 100     for (i = 0; i < ARRAY_SIZE(compat_table); i++) {
 101         if (compat_table[i].pvr == pvr) {
 102             return &compat_table[i];
 103         }
 104     }
 105     return NULL;
 106 }
 107
 108 static bool pcc_compat(PowerPCCPUClass *pcc, uint32_t compat_pvr,
 109                        uint32_t min_compat_pvr, uint32_t max_compat_pvr)
 110 {
 111     const CompatInfo *compat = compat_by_pvr(compat_pvr);
 112     const CompatInfo *min = compat_by_pvr(min_compat_pvr);
 113     const CompatInfo *max = compat_by_pvr(max_compat_pvr);
 114
 115     g_assert(!min_compat_pvr || min);
 116     g_assert(!max_compat_pvr || max);
 117
 118     if (!compat) {
 119         /* Not a recognized logical PVR */
 120         return false;
 121     }
 122     if ((min && (compat < min)) || (max && (compat > max))) {
 123         /* Outside specified range */
 124         return false;
 125     }
 126     if (!(pcc->pcr_supported & compat->pcr_level)) {
 127         /* Not supported by this CPU */
 128         return false;
 129     }
 130     return true;
 131 }
 132
 133 bool ppc_check_compat(PowerPCCPU *cpu, uint32_t compat_pvr,
 134                       uint32_t min_compat_pvr, uint32_t max_compat_pvr)
 135 {
 136     PowerPCCPUClass *pcc = POWERPC_CPU_GET_CLASS(cpu);
 137
 138 #if !defined(CONFIG_USER_ONLY)
 139     g_assert(cpu->vhyp);
 140 #endif
 141
 142     return pcc_compat(pcc, compat_pvr, min_compat_pvr, max_compat_pvr);
 143 }
 144
 145 bool ppc_type_check_compat(const char *cputype, uint32_t compat_pvr,
 146                            uint32_t min_compat_pvr, uint32_t max_compat_pvr)
 147 {
 148     PowerPCCPUClass *pcc = POWERPC_CPU_CLASS(object_class_by_name(cputype));
 149     return pcc_compat(pcc, compat_pvr, min_compat_pvr, max_compat_pvr);
 150 }
 151
 152 void ppc_set_compat(PowerPCCPU *cpu, uint32_t compat_pvr, Error **errp)
 153 {
 154     const CompatInfo *compat = compat_by_pvr(compat_pvr);
 155     CPUPPCState *env = &cpu->env;
 156     PowerPCCPUClass *pcc = POWERPC_CPU_GET_CLASS(cpu);
 157     uint64_t pcr;
 158
 159     if (!compat_pvr) {
 160         pcr = 0;
 161     } else if (!compat) {
 162         error_setg(errp, "Unknown compatibility PVR 0x%08"PRIx32, compat_pvr);
 163         return;
 164     } else if (!ppc_check_compat(cpu, compat_pvr, 0, 0)) {
 165         error_setg(errp, "Compatibility PVR 0x%08"PRIx32" not valid for CPU",
 166                    compat_pvr);
 167         return;
 168     } else {
 169         pcr = compat->pcr;
 170     }
 171
 172     cpu_synchronize_state(CPU(cpu));
 173
 174     if (kvm_enabled() && cpu->compat_pvr != compat_pvr) {
 175         int ret = kvmppc_set_compat(cpu, compat_pvr);
 176         if (ret < 0) {
 177             error_setg_errno(errp, -ret,
 178                              "Unable to set CPU compatibility mode in KVM");
 179             return;
 180         }
 181     }
 182
 183     cpu->compat_pvr = compat_pvr;
 184     env->spr[SPR_PCR] = pcr & pcc->pcr_mask;
 185 }
 186
 187 typedef struct {
 188     uint32_t compat_pvr;
 189     Error *err;
 190 } SetCompatState;
 191
 192 static void do_set_compat(CPUState *cs, run_on_cpu_data arg)
 193 {
 194     PowerPCCPU *cpu = POWERPC_CPU(cs);
 195     SetCompatState *s = arg.host_ptr;
 196
 197     ppc_set_compat(cpu, s->compat_pvr, &s->err);
 198 }
 199
 200 void ppc_set_compat_all(uint32_t compat_pvr, Error **errp)
 201 {
 202     CPUState *cs;
 203
 204     CPU_FOREACH(cs) {
 205         SetCompatState s = {
 206             .compat_pvr = compat_pvr,
 207             .err = NULL,
 208         };
 209
 210         run_on_cpu(cs, do_set_compat, RUN_ON_CPU_HOST_PTR(&s));
 211
 212         if (s.err) {
 213             error_propagate(errp, s.err);
 214             return;
 215         }
 216     }
 217 }
 218
 219 int ppc_compat_max_vthreads(PowerPCCPU *cpu)
 220 {
 221     const CompatInfo *compat = compat_by_pvr(cpu->compat_pvr);
 222     int n_threads = CPU(cpu)->nr_threads;
 223
 224     if (cpu->compat_pvr) {
 225         g_assert(compat);
 226         n_threads = MIN(n_threads, compat->max_vthreads);
 227     }
 228
 229     return n_threads;
 230 }
 231
 232 static void ppc_compat_prop_get(Object *obj, Visitor *v, const char *name,
 233                                 void *opaque, Error **errp)
 234 {
 235     uint32_t compat_pvr = *((uint32_t *)opaque);
 236     const char *value;
 237
 238     if (!compat_pvr) {
 239         value = "";
 240     } else {
 241         const CompatInfo *compat = compat_by_pvr(compat_pvr);
 242
 243         g_assert(compat);
 244
 245         value = compat->name;
 246     }
 247
 248     visit_type_str(v, name, (char **)&value, errp);
 249 }
 250
 251 static void ppc_compat_prop_set(Object *obj, Visitor *v, const char *name,
 252                                 void *opaque, Error **errp)
 253 {
 254     Error *local_err = NULL;
 255     char *value;
 256     uint32_t compat_pvr;
 257
 258     visit_type_str(v, name, &value, &local_err);
 259     if (local_err) {
 260         error_propagate(errp, local_err);
 261         return;
 262     }
 263
 264     if (strcmp(value, "") == 0) {
 265         compat_pvr = 0;
 266     } else {
 267         int i;
 268         const CompatInfo *compat = NULL;
 269
 270         for (i = 0; i < ARRAY_SIZE(compat_table); i++) {
 271             if (strcmp(value, compat_table[i].name) == 0) {
 272                 compat = &compat_table[i];
 273                 break;
 274
 275             }
 276         }
 277
 278         if (!compat) {
 279             error_setg(errp, "Invalid compatibility mode \"%s\"", value);
 280             goto out;
 281         }
 282         compat_pvr = compat->pvr;
 283     }
 284
 285     *((uint32_t *)opaque) = compat_pvr;
 286
 287 out:
 288     g_free(value);
 289 }
 290
 291 void ppc_compat_add_property(Object *obj, const char *name,
 292                              uint32_t *compat_pvr, const char *basedesc,
 293                              Error **errp)
 294 {
 295     Error *local_err = NULL;
 296     gchar *namesv[ARRAY_SIZE(compat_table) + 1];
 297     gchar *names, *desc;
 298     int i;
 299
 300     object_property_add(obj, name, "string",
 301                         ppc_compat_prop_get, ppc_compat_prop_set, NULL,
 302                         compat_pvr, &local_err);
 303     if (local_err) {
 304         goto out;
 305     }
 306
 307     for (i = 0; i < ARRAY_SIZE(compat_table); i++) {
 308         /*
 309          * Have to discard const here, because g_strjoinv() takes
 310          * (gchar **), not (const gchar **) :(
 311          */
 312         namesv[i] = (gchar *)compat_table[i].name;
 313     }
 314     namesv[ARRAY_SIZE(compat_table)] = NULL;
 315
 316     names = g_strjoinv(", ", namesv);
 317     desc = g_strdup_printf("%s. Valid values are %s.", basedesc, names);
 318     object_property_set_description(obj, name, desc, &local_err);
 319
 320     g_free(names);
 321     g_free(desc);
 322
 323 out:
 324     error_propagate(errp, local_err);
 325 }