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 2.1 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 "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_10 | PCR_COMPAT_3_00 | PCR_COMPAT_2_07 |
  55                PCR_COMPAT_2_06 | 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_10 | PCR_COMPAT_3_00 | PCR_COMPAT_2_07 |
  63                PCR_COMPAT_2_06 | PCR_TM_DIS,
  64         .pcr_level = PCR_COMPAT_2_06,
  65         .max_vthreads = 4,
  66     },
  67     {
  68         .name = "power7+",
  69         .pvr = CPU_POWERPC_LOGICAL_2_06_PLUS,
  70         .pcr = PCR_COMPAT_3_10 | PCR_COMPAT_3_00 | PCR_COMPAT_2_07 |
  71                PCR_COMPAT_2_06 | PCR_TM_DIS,
  72         .pcr_level = PCR_COMPAT_2_06,
  73         .max_vthreads = 4,
  74     },
  75     { /* POWER8, ISA2.07 */
  76         .name = "power8",
  77         .pvr = CPU_POWERPC_LOGICAL_2_07,
  78         .pcr = PCR_COMPAT_3_10 | PCR_COMPAT_3_00 | PCR_COMPAT_2_07,
  79         .pcr_level = PCR_COMPAT_2_07,
  80         .max_vthreads = 8,
  81     },
  82     { /* POWER9, ISA3.00 */
  83         .name = "power9",
  84         .pvr = CPU_POWERPC_LOGICAL_3_00,
  85         .pcr = PCR_COMPAT_3_10 | PCR_COMPAT_3_00,
  86         .pcr_level = PCR_COMPAT_3_00,
  87         /*
  88          * POWER9 hardware only supports 4 threads / core, but this
  89          * limit is for guests.  We need to support 8 vthreads/vcore
  90          * on POWER9 for POWER8 compatibility guests, and it's very
  91          * confusing if half of the threads disappear from the guest
  92          * if it announces it's POWER9 aware at CAS time.
  93          */
  94         .max_vthreads = 8,
  95     },
  96     { /* POWER10, ISA3.10 */
  97         .name = "power10",
  98         .pvr = CPU_POWERPC_LOGICAL_3_10,
  99         .pcr = PCR_COMPAT_3_10,
 100         .pcr_level = PCR_COMPAT_3_10,
 101         .max_vthreads = 8,
 102     },
 103 };
 104
 105 static const CompatInfo *compat_by_pvr(uint32_t pvr)
 106 {
 107     int i;
 108
 109     for (i = 0; i < ARRAY_SIZE(compat_table); i++) {
 110         if (compat_table[i].pvr == pvr) {
 111             return &compat_table[i];
 112         }
 113     }
 114     return NULL;
 115 }
 116
 117 static bool pcc_compat(PowerPCCPUClass *pcc, uint32_t compat_pvr,
 118                        uint32_t min_compat_pvr, uint32_t max_compat_pvr)
 119 {
 120     const CompatInfo *compat = compat_by_pvr(compat_pvr);
 121     const CompatInfo *min = compat_by_pvr(min_compat_pvr);
 122     const CompatInfo *max = compat_by_pvr(max_compat_pvr);
 123
 124     g_assert(!min_compat_pvr || min);
 125     g_assert(!max_compat_pvr || max);
 126
 127     if (!compat) {
 128         /* Not a recognized logical PVR */
 129         return false;
 130     }
 131     if ((min && (compat < min)) || (max && (compat > max))) {
 132         /* Outside specified range */
 133         return false;
 134     }
 135     if (!(pcc->pcr_supported & compat->pcr_level)) {
 136         /* Not supported by this CPU */
 137         return false;
 138     }
 139     return true;
 140 }
 141
 142 bool ppc_check_compat(PowerPCCPU *cpu, uint32_t compat_pvr,
 143                       uint32_t min_compat_pvr, uint32_t max_compat_pvr)
 144 {
 145     PowerPCCPUClass *pcc = POWERPC_CPU_GET_CLASS(cpu);
 146
 147 #if !defined(CONFIG_USER_ONLY)
 148     g_assert(cpu->vhyp);
 149 #endif
 150
 151     return pcc_compat(pcc, compat_pvr, min_compat_pvr, max_compat_pvr);
 152 }
 153
 154 bool ppc_type_check_compat(const char *cputype, uint32_t compat_pvr,
 155                            uint32_t min_compat_pvr, uint32_t max_compat_pvr)
 156 {
 157     PowerPCCPUClass *pcc = POWERPC_CPU_CLASS(object_class_by_name(cputype));
 158     return pcc_compat(pcc, compat_pvr, min_compat_pvr, max_compat_pvr);
 159 }
 160
 161 int ppc_set_compat(PowerPCCPU *cpu, uint32_t compat_pvr, Error **errp)
 162 {
 163     const CompatInfo *compat = compat_by_pvr(compat_pvr);
 164     CPUPPCState *env = &cpu->env;
 165     PowerPCCPUClass *pcc = POWERPC_CPU_GET_CLASS(cpu);
 166     uint64_t pcr;
 167
 168     if (!compat_pvr) {
 169         pcr = 0;
 170     } else if (!compat) {
 171         error_setg(errp, "Unknown compatibility PVR 0x%08"PRIx32, compat_pvr);
 172         return -EINVAL;
 173     } else if (!ppc_check_compat(cpu, compat_pvr, 0, 0)) {
 174         error_setg(errp, "Compatibility PVR 0x%08"PRIx32" not valid for CPU",
 175                    compat_pvr);
 176         return -EINVAL;
 177     } else {
 178         pcr = compat->pcr;
 179     }
 180
 181     cpu_synchronize_state(CPU(cpu));
 182
 183     if (kvm_enabled() && cpu->compat_pvr != compat_pvr) {
 184         int ret = kvmppc_set_compat(cpu, compat_pvr);
 185         if (ret < 0) {
 186             error_setg_errno(errp, -ret,
 187                              "Unable to set CPU compatibility mode in KVM");
 188             return ret;
 189         }
 190     }
 191
 192     cpu->compat_pvr = compat_pvr;
 193     env->spr[SPR_PCR] = pcr & pcc->pcr_mask;
 194     return 0;
 195 }
 196
 197 typedef struct {
 198     uint32_t compat_pvr;
 199     Error **errp;
 200     int ret;
 201 } SetCompatState;
 202
 203 static void do_set_compat(CPUState *cs, run_on_cpu_data arg)
 204 {
 205     PowerPCCPU *cpu = POWERPC_CPU(cs);
 206     SetCompatState *s = arg.host_ptr;
 207
 208     s->ret = ppc_set_compat(cpu, s->compat_pvr, s->errp);
 209 }
 210
 211 int ppc_set_compat_all(uint32_t compat_pvr, Error **errp)
 212 {
 213     CPUState *cs;
 214
 215     CPU_FOREACH(cs) {
 216         SetCompatState s = {
 217             .compat_pvr = compat_pvr,
 218             .errp = errp,
 219             .ret = 0,
 220         };
 221
 222         run_on_cpu(cs, do_set_compat, RUN_ON_CPU_HOST_PTR(&s));
 223
 224         if (s.ret < 0) {
 225             return s.ret;
 226         }
 227     }
 228
 229     return 0;
 230 }
 231
 232 int ppc_compat_max_vthreads(PowerPCCPU *cpu)
 233 {
 234     const CompatInfo *compat = compat_by_pvr(cpu->compat_pvr);
 235     int n_threads = CPU(cpu)->nr_threads;
 236
 237     if (cpu->compat_pvr) {
 238         g_assert(compat);
 239         n_threads = MIN(n_threads, compat->max_vthreads);
 240     }
 241
 242     return n_threads;
 243 }
 244
 245 static void ppc_compat_prop_get(Object *obj, Visitor *v, const char *name,
 246                                 void *opaque, Error **errp)
 247 {
 248     uint32_t compat_pvr = *((uint32_t *)opaque);
 249     const char *value;
 250
 251     if (!compat_pvr) {
 252         value = "";
 253     } else {
 254         const CompatInfo *compat = compat_by_pvr(compat_pvr);
 255
 256         g_assert(compat);
 257
 258         value = compat->name;
 259     }
 260
 261     visit_type_str(v, name, (char **)&value, errp);
 262 }
 263
 264 static void ppc_compat_prop_set(Object *obj, Visitor *v, const char *name,
 265                                 void *opaque, Error **errp)
 266 {
 267     char *value;
 268     uint32_t compat_pvr;
 269
 270     if (!visit_type_str(v, name, &value, errp)) {
 271         return;
 272     }
 273
 274     if (strcmp(value, "") == 0) {
 275         compat_pvr = 0;
 276     } else {
 277         int i;
 278         const CompatInfo *compat = NULL;
 279
 280         for (i = 0; i < ARRAY_SIZE(compat_table); i++) {
 281             if (strcmp(value, compat_table[i].name) == 0) {
 282                 compat = &compat_table[i];
 283                 break;
 284
 285             }
 286         }
 287
 288         if (!compat) {
 289             error_setg(errp, "Invalid compatibility mode \"%s\"", value);
 290             goto out;
 291         }
 292         compat_pvr = compat->pvr;
 293     }
 294
 295     *((uint32_t *)opaque) = compat_pvr;
 296
 297 out:
 298     g_free(value);
 299 }
 300
 301 void ppc_compat_add_property(Object *obj, const char *name,
 302                              uint32_t *compat_pvr, const char *basedesc)
 303 {
 304     gchar *namesv[ARRAY_SIZE(compat_table) + 1];
 305     gchar *names, *desc;
 306     int i;
 307
 308     object_property_add(obj, name, "string",
 309                         ppc_compat_prop_get, ppc_compat_prop_set, NULL,
 310                         compat_pvr);
 311
 312     for (i = 0; i < ARRAY_SIZE(compat_table); i++) {
 313         /*
 314          * Have to discard const here, because g_strjoinv() takes
 315          * (gchar **), not (const gchar **) :(
 316          */
 317         namesv[i] = (gchar *)compat_table[i].name;
 318     }
 319     namesv[ARRAY_SIZE(compat_table)] = NULL;
 320
 321     names = g_strjoinv(", ", namesv);
 322     desc = g_strdup_printf("%s. Valid values are %s.", basedesc, names);
 323     object_property_set_description(obj, name, desc);
 324
 325     g_free(names);
 326     g_free(desc);
 327 }