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