arch/arm/xen/enlighten.c

   1 #include <xen/xen.h>
   2 #include <xen/events.h>
   3 #include <xen/grant_table.h>
   4 #include <xen/hvm.h>
   5 #include <xen/interface/vcpu.h>
   6 #include <xen/interface/xen.h>
   7 #include <xen/interface/memory.h>
   8 #include <xen/interface/hvm/params.h>
   9 #include <xen/features.h>
  10 #include <xen/platform_pci.h>
  11 #include <xen/xenbus.h>
  12 #include <xen/page.h>
  13 #include <xen/interface/sched.h>
  14 #include <xen/xen-ops.h>
  15 #include <asm/xen/hypervisor.h>
  16 #include <asm/xen/hypercall.h>
  17 #include <asm/xen/xen-ops.h>
  18 #include <asm/system_misc.h>
  19 #include <asm/efi.h>
  20 #include <linux/interrupt.h>
  21 #include <linux/irqreturn.h>
  22 #include <linux/module.h>
  23 #include <linux/of.h>
  24 #include <linux/of_fdt.h>
  25 #include <linux/of_irq.h>
  26 #include <linux/of_address.h>
  27 #include <linux/cpuidle.h>
  28 #include <linux/cpufreq.h>
  29 #include <linux/cpu.h>
  30 #include <linux/console.h>
  31 #include <linux/pvclock_gtod.h>
  32 #include <linux/time64.h>
  33 #include <linux/timekeeping.h>
  34 #include <linux/timekeeper_internal.h>
  35 #include <linux/acpi.h>
  36
  37 #include <linux/mm.h>
  38
  39 struct start_info _xen_start_info;
  40 struct start_info *xen_start_info = &_xen_start_info;
  41 EXPORT_SYMBOL(xen_start_info);
  42
  43 enum xen_domain_type xen_domain_type = XEN_NATIVE;
  44 EXPORT_SYMBOL(xen_domain_type);
  45
  46 struct shared_info xen_dummy_shared_info;
  47 struct shared_info *HYPERVISOR_shared_info = (void *)&xen_dummy_shared_info;
  48
  49 DEFINE_PER_CPU(struct vcpu_info *, xen_vcpu);
  50 static struct vcpu_info __percpu *xen_vcpu_info;
  51
  52 /* Linux <-> Xen vCPU id mapping */
  53 DEFINE_PER_CPU(uint32_t, xen_vcpu_id);
  54 EXPORT_PER_CPU_SYMBOL(xen_vcpu_id);
  55
  56 /* These are unused until we support booting "pre-ballooned" */
  57 unsigned long xen_released_pages;
  58 struct xen_memory_region xen_extra_mem[XEN_EXTRA_MEM_MAX_REGIONS] __initdata;
  59
  60 static __read_mostly unsigned int xen_events_irq;
  61
  62 int xen_remap_domain_gfn_array(struct vm_area_struct *vma,
  63                                unsigned long addr,
  64                                xen_pfn_t *gfn, int nr,
  65                                int *err_ptr, pgprot_t prot,
  66                                unsigned domid,
  67                                struct page **pages)
  68 {
  69         return xen_xlate_remap_gfn_array(vma, addr, gfn, nr, err_ptr,
  70                                          prot, domid, pages);
  71 }
  72 EXPORT_SYMBOL_GPL(xen_remap_domain_gfn_array);
  73
  74 /* Not used by XENFEAT_auto_translated guests. */
  75 int xen_remap_domain_gfn_range(struct vm_area_struct *vma,
  76                               unsigned long addr,
  77                               xen_pfn_t gfn, int nr,
  78                               pgprot_t prot, unsigned domid,
  79                               struct page **pages)
  80 {
  81         return -ENOSYS;
  82 }
  83 EXPORT_SYMBOL_GPL(xen_remap_domain_gfn_range);
  84
  85 int xen_unmap_domain_gfn_range(struct vm_area_struct *vma,
  86                                int nr, struct page **pages)
  87 {
  88         return xen_xlate_unmap_gfn_range(vma, nr, pages);
  89 }
  90 EXPORT_SYMBOL_GPL(xen_unmap_domain_gfn_range);
  91
  92 /* Not used by XENFEAT_auto_translated guests. */
  93 int xen_remap_domain_mfn_array(struct vm_area_struct *vma,
  94                                unsigned long addr,
  95                                xen_pfn_t *mfn, int nr,
  96                                int *err_ptr, pgprot_t prot,
  97                                unsigned int domid, struct page **pages)
  98 {
  99         return -ENOSYS;
 100 }
 101 EXPORT_SYMBOL_GPL(xen_remap_domain_mfn_array);
 102
 103 static void xen_read_wallclock(struct timespec64 *ts)
 104 {
 105         u32 version;
 106         struct timespec64 now, ts_monotonic;
 107         struct shared_info *s = HYPERVISOR_shared_info;
 108         struct pvclock_wall_clock *wall_clock = &(s->wc);
 109
 110         /* get wallclock at system boot */
 111         do {
 112                 version = wall_clock->version;
 113                 rmb();          /* fetch version before time */
 114                 now.tv_sec  = ((uint64_t)wall_clock->sec_hi << 32) | wall_clock->sec;
 115                 now.tv_nsec = wall_clock->nsec;
 116                 rmb();          /* fetch time before checking version */
 117         } while ((wall_clock->version & 1) || (version != wall_clock->version));
 118
 119         /* time since system boot */
 120         ktime_get_ts64(&ts_monotonic);
 121         *ts = timespec64_add(now, ts_monotonic);
 122 }
 123
 124 static int xen_pvclock_gtod_notify(struct notifier_block *nb,
 125                                    unsigned long was_set, void *priv)
 126 {
 127         /* Protected by the calling core code serialization */
 128         static struct timespec64 next_sync;
 129
 130         struct xen_platform_op op;
 131         struct timespec64 now, system_time;
 132         struct timekeeper *tk = priv;
 133
 134         now.tv_sec = tk->xtime_sec;
 135         now.tv_nsec = (long)(tk->tkr_mono.xtime_nsec >> tk->tkr_mono.shift);
 136         system_time = timespec64_add(now, tk->wall_to_monotonic);
 137
 138         /*
 139          * We only take the expensive HV call when the clock was set
 140          * or when the 11 minutes RTC synchronization time elapsed.
 141          */
 142         if (!was_set && timespec64_compare(&now, &next_sync) < 0)
 143                 return NOTIFY_OK;
 144
 145         op.cmd = XENPF_settime64;
 146         op.u.settime64.mbz = 0;
 147         op.u.settime64.secs = now.tv_sec;
 148         op.u.settime64.nsecs = now.tv_nsec;
 149         op.u.settime64.system_time = timespec64_to_ns(&system_time);
 150         (void)HYPERVISOR_platform_op(&op);
 151
 152         /*
 153          * Move the next drift compensation time 11 minutes
 154          * ahead. That's emulating the sync_cmos_clock() update for
 155          * the hardware RTC.
 156          */
 157         next_sync = now;
 158         next_sync.tv_sec += 11 * 60;
 159
 160         return NOTIFY_OK;
 161 }
 162
 163 static struct notifier_block xen_pvclock_gtod_notifier = {
 164         .notifier_call = xen_pvclock_gtod_notify,
 165 };
 166
 167 static int xen_starting_cpu(unsigned int cpu)
 168 {
 169         struct vcpu_register_vcpu_info info;
 170         struct vcpu_info *vcpup;
 171         int err;
 172
 173         /*
 174          * VCPUOP_register_vcpu_info cannot be called twice for the same
 175          * vcpu, so if vcpu_info is already registered, just get out. This
 176          * can happen with cpu-hotplug.
 177          */
 178         if (per_cpu(xen_vcpu, cpu) != NULL)
 179                 goto after_register_vcpu_info;
 180
 181         pr_info("Xen: initializing cpu%d\n", cpu);
 182         vcpup = per_cpu_ptr(xen_vcpu_info, cpu);
 183
 184         info.mfn = virt_to_gfn(vcpup);
 185         info.offset = xen_offset_in_page(vcpup);
 186
 187         err = HYPERVISOR_vcpu_op(VCPUOP_register_vcpu_info, xen_vcpu_nr(cpu),
 188                                  &info);
 189         BUG_ON(err);
 190         per_cpu(xen_vcpu, cpu) = vcpup;
 191
 192         xen_setup_runstate_info(cpu);
 193
 194 after_register_vcpu_info:
 195         enable_percpu_irq(xen_events_irq, 0);
 196         return 0;
 197 }
 198
 199 static int xen_dying_cpu(unsigned int cpu)
 200 {
 201         disable_percpu_irq(xen_events_irq);
 202         return 0;
 203 }
 204
 205 void xen_reboot(int reason)
 206 {
 207         struct sched_shutdown r = { .reason = reason };
 208         int rc;
 209
 210         rc = HYPERVISOR_sched_op(SCHEDOP_shutdown, &r);
 211         BUG_ON(rc);
 212 }
 213
 214 static void xen_restart(enum reboot_mode reboot_mode, const char *cmd)
 215 {
 216         xen_reboot(SHUTDOWN_reboot);
 217 }
 218
 219
 220 static void xen_power_off(void)
 221 {
 222         xen_reboot(SHUTDOWN_poweroff);
 223 }
 224
 225 static irqreturn_t xen_arm_callback(int irq, void *arg)
 226 {
 227         xen_hvm_evtchn_do_upcall();
 228         return IRQ_HANDLED;
 229 }
 230
 231 static __initdata struct {
 232         const char *compat;
 233         const char *prefix;
 234         const char *version;
 235         bool found;
 236 } hyper_node = {"xen,xen", "xen,xen-", NULL, false};
 237
 238 static int __init fdt_find_hyper_node(unsigned long node, const char *uname,
 239                                       int depth, void *data)
 240 {
 241         const void *s = NULL;
 242         int len;
 243
 244         if (depth != 1 || strcmp(uname, "hypervisor") != 0)
 245                 return 0;
 246
 247         if (of_flat_dt_is_compatible(node, hyper_node.compat))
 248                 hyper_node.found = true;
 249
 250         s = of_get_flat_dt_prop(node, "compatible", &len);
 251         if (strlen(hyper_node.prefix) + 3  < len &&
 252             !strncmp(hyper_node.prefix, s, strlen(hyper_node.prefix)))
 253                 hyper_node.version = s + strlen(hyper_node.prefix);
 254
 255         /*
 256          * Check if Xen supports EFI by checking whether there is the
 257          * "/hypervisor/uefi" node in DT. If so, runtime services are available
 258          * through proxy functions (e.g. in case of Xen dom0 EFI implementation
 259          * they call special hypercall which executes relevant EFI functions)
 260          * and that is why they are always enabled.
 261          */
 262         if (IS_ENABLED(CONFIG_XEN_EFI)) {
 263                 if ((of_get_flat_dt_subnode_by_name(node, "uefi") > 0) &&
 264                     !efi_runtime_disabled())
 265                         set_bit(EFI_RUNTIME_SERVICES, &efi.flags);
 266         }
 267
 268         return 0;
 269 }
 270
 271 /*
 272  * see Documentation/devicetree/bindings/arm/xen.txt for the
 273  * documentation of the Xen Device Tree format.
 274  */
 275 #define GRANT_TABLE_PHYSADDR 0
 276 void __init xen_early_init(void)
 277 {
 278         of_scan_flat_dt(fdt_find_hyper_node, NULL);
 279         if (!hyper_node.found) {
 280                 pr_debug("No Xen support\n");
 281                 return;
 282         }
 283
 284         if (hyper_node.version == NULL) {
 285                 pr_debug("Xen version not found\n");
 286                 return;
 287         }
 288
 289         pr_info("Xen %s support found\n", hyper_node.version);
 290
 291         xen_domain_type = XEN_HVM_DOMAIN;
 292
 293         xen_setup_features();
 294
 295         if (xen_feature(XENFEAT_dom0))
 296                 xen_start_info->flags |= SIF_INITDOMAIN|SIF_PRIVILEGED;
 297         else
 298                 xen_start_info->flags &= ~(SIF_INITDOMAIN|SIF_PRIVILEGED);
 299
 300         if (!console_set_on_cmdline && !xen_initial_domain())
 301                 add_preferred_console("hvc", 0, NULL);
 302 }
 303
 304 static void __init xen_acpi_guest_init(void)
 305 {
 306 #ifdef CONFIG_ACPI
 307         struct xen_hvm_param a;
 308         int interrupt, trigger, polarity;
 309
 310         a.domid = DOMID_SELF;
 311         a.index = HVM_PARAM_CALLBACK_IRQ;
 312
 313         if (HYPERVISOR_hvm_op(HVMOP_get_param, &a)
 314             || (a.value >> 56) != HVM_PARAM_CALLBACK_TYPE_PPI) {
 315                 xen_events_irq = 0;
 316                 return;
 317         }
 318
 319         interrupt = a.value & 0xff;
 320         trigger = ((a.value >> 8) & 0x1) ? ACPI_EDGE_SENSITIVE
 321                                          : ACPI_LEVEL_SENSITIVE;
 322         polarity = ((a.value >> 8) & 0x2) ? ACPI_ACTIVE_LOW
 323                                           : ACPI_ACTIVE_HIGH;
 324         xen_events_irq = acpi_register_gsi(NULL, interrupt, trigger, polarity);
 325 #endif
 326 }
 327
 328 static void __init xen_dt_guest_init(void)
 329 {
 330         struct device_node *xen_node;
 331
 332         xen_node = of_find_compatible_node(NULL, NULL, "xen,xen");
 333         if (!xen_node) {
 334                 pr_err("Xen support was detected before, but it has disappeared\n");
 335                 return;
 336         }
 337
 338         xen_events_irq = irq_of_parse_and_map(xen_node, 0);
 339 }
 340
 341 static int __init xen_guest_init(void)
 342 {
 343         struct xen_add_to_physmap xatp;
 344         struct shared_info *shared_info_page = NULL;
 345         int cpu;
 346
 347         if (!xen_domain())
 348                 return 0;
 349
 350         if (!acpi_disabled)
 351                 xen_acpi_guest_init();
 352         else
 353                 xen_dt_guest_init();
 354
 355         if (!xen_events_irq) {
 356                 pr_err("Xen event channel interrupt not found\n");
 357                 return -ENODEV;
 358         }
 359
 360         /*
 361          * The fdt parsing codes have set EFI_RUNTIME_SERVICES if Xen EFI
 362          * parameters are found. Force enable runtime services.
 363          */
 364         if (efi_enabled(EFI_RUNTIME_SERVICES))
 365                 xen_efi_runtime_setup();
 366
 367         shared_info_page = (struct shared_info *)get_zeroed_page(GFP_KERNEL);
 368
 369         if (!shared_info_page) {
 370                 pr_err("not enough memory\n");
 371                 return -ENOMEM;
 372         }
 373         xatp.domid = DOMID_SELF;
 374         xatp.idx = 0;
 375         xatp.space = XENMAPSPACE_shared_info;
 376         xatp.gpfn = virt_to_gfn(shared_info_page);
 377         if (HYPERVISOR_memory_op(XENMEM_add_to_physmap, &xatp))
 378                 BUG();
 379
 380         HYPERVISOR_shared_info = (struct shared_info *)shared_info_page;
 381
 382         /* xen_vcpu is a pointer to the vcpu_info struct in the shared_info
 383          * page, we use it in the event channel upcall and in some pvclock
 384          * related functions.
 385          * The shared info contains exactly 1 CPU (the boot CPU). The guest
 386          * is required to use VCPUOP_register_vcpu_info to place vcpu info
 387          * for secondary CPUs as they are brought up.
 388          * For uniformity we use VCPUOP_register_vcpu_info even on cpu0.
 389          */
 390         xen_vcpu_info = alloc_percpu(struct vcpu_info);
 391         if (xen_vcpu_info == NULL)
 392                 return -ENOMEM;
 393
 394         /* Direct vCPU id mapping for ARM guests. */
 395         for_each_possible_cpu(cpu)
 396                 per_cpu(xen_vcpu_id, cpu) = cpu;
 397
 398         xen_auto_xlat_grant_frames.count = gnttab_max_grant_frames();
 399         if (xen_xlate_map_ballooned_pages(&xen_auto_xlat_grant_frames.pfn,
 400                                           &xen_auto_xlat_grant_frames.vaddr,
 401                                           xen_auto_xlat_grant_frames.count)) {
 402                 free_percpu(xen_vcpu_info);
 403                 return -ENOMEM;
 404         }
 405         gnttab_init();
 406         if (!xen_initial_domain())
 407                 xenbus_probe(NULL);
 408
 409         /*
 410          * Making sure board specific code will not set up ops for
 411          * cpu idle and cpu freq.
 412          */
 413         disable_cpuidle();
 414         disable_cpufreq();
 415
 416         xen_init_IRQ();
 417
 418         if (request_percpu_irq(xen_events_irq, xen_arm_callback,
 419                                "events", &xen_vcpu)) {
 420                 pr_err("Error request IRQ %d\n", xen_events_irq);
 421                 return -EINVAL;
 422         }
 423
 424         xen_time_setup_guest();
 425
 426         if (xen_initial_domain())
 427                 pvclock_gtod_register_notifier(&xen_pvclock_gtod_notifier);
 428
 429         return cpuhp_setup_state(CPUHP_AP_ARM_XEN_STARTING,
 430                                  "arm/xen:starting", xen_starting_cpu,
 431                                  xen_dying_cpu);
 432 }
 433 early_initcall(xen_guest_init);
 434
 435 static int __init xen_pm_init(void)
 436 {
 437         if (!xen_domain())
 438                 return -ENODEV;
 439
 440         pm_power_off = xen_power_off;
 441         arm_pm_restart = xen_restart;
 442         if (!xen_initial_domain()) {
 443                 struct timespec64 ts;
 444                 xen_read_wallclock(&ts);
 445                 do_settimeofday64(&ts);
 446         }
 447
 448         return 0;
 449 }
 450 late_initcall(xen_pm_init);
 451
 452
 453 /* empty stubs */
 454 void xen_arch_pre_suspend(void) { }
 455 void xen_arch_post_suspend(int suspend_cancelled) { }
 456 void xen_timer_resume(void) { }
 457 void xen_arch_resume(void) { }
 458 void xen_arch_suspend(void) { }
 459
 460
 461 /* In the hypercall.S file. */
 462 EXPORT_SYMBOL_GPL(HYPERVISOR_event_channel_op);
 463 EXPORT_SYMBOL_GPL(HYPERVISOR_grant_table_op);
 464 EXPORT_SYMBOL_GPL(HYPERVISOR_xen_version);
 465 EXPORT_SYMBOL_GPL(HYPERVISOR_console_io);
 466 EXPORT_SYMBOL_GPL(HYPERVISOR_sched_op);
 467 EXPORT_SYMBOL_GPL(HYPERVISOR_hvm_op);
 468 EXPORT_SYMBOL_GPL(HYPERVISOR_memory_op);
 469 EXPORT_SYMBOL_GPL(HYPERVISOR_physdev_op);
 470 EXPORT_SYMBOL_GPL(HYPERVISOR_vcpu_op);
 471 EXPORT_SYMBOL_GPL(HYPERVISOR_tmem_op);
 472 EXPORT_SYMBOL_GPL(HYPERVISOR_platform_op);
 473 EXPORT_SYMBOL_GPL(HYPERVISOR_multicall);
 474 EXPORT_SYMBOL_GPL(HYPERVISOR_vm_assist);
 475 EXPORT_SYMBOL_GPL(HYPERVISOR_dm_op);
 476 EXPORT_SYMBOL_GPL(privcmd_call);